The contiguous U.S. average temperature during May was 62.4°F, 2.2°F above average, ranking 11th warmest in the 129-year record.
Generally, temperatures were below average along the East Coast, from Vermont to northern Florida. Temperatures were above average across much of the West to the Mississippi River Valley and in the Florida Peninsula.
For the month of May, Washington ranked warmest on record for May while Oregon, Idaho and Montana each ranked fifth warmest on record. Four additional states ranked among their top-10 warmest May on record. Conversely, South Carolina ranked 10th coldest on record for the month.
The contiguous U.S. average maximum (daytime) temperature during May was 75.1°F, 2.2°F above the 20th century average, ranking 16th warmest on record. Maximum temperatures were above average across much of the West to the Mississippi River Valley and in parts of the Northeast and Florida Peninsula. Temperatures were below average across much of the Mid-Atlantic and Southeast and in parts of California and southern Texas. Washington ranked third warmest while Montana ranked seventh warmest, with two additional northern states ranking among their top-10 warmest May for daytime temperatures. South Carolina ranked second coldest May on record with two additional southeastern states ranking among their top-10 coldest May for daytime temperatures.
The contiguous U.S. average minimum (nighttime) temperature during May was 49.7°F, 2.3°F below the 20th century average, ranking 10th warmest in the historical record. Minimum temperatures were above average across much of the West to the Mississippi River Valley and Florida. Temperatures were near or below normal from the eastern Great Lakes to the Northeast and in parts of the Southeast. Washington, Oregon and Montana ranked warmest May on record, while five additional states experienced a top-10 warmest May for nighttime temperatures.
The Alaska statewide May temperature was 39.8°F, 2.0°F above the long-term average. This ranked in the warmest third of the 99-year period of record for the state. Temperatures were above average across much of the north, east and Panhandle, with near-normal temperatures observed across much of the western and southern portions of the state, including the Aleutians, during the month.
Based on NOAA's Residential Energy Demand Temperature Index (REDTI), the contiguous U.S. temperature-related energy demand during May was 65 percent of average and the 43rd-lowest value in the 129-year period of record.
The May precipitation total for the contiguous U.S. was 2.56 inches, 0.35 inch above average, ranking in the driest third of the 129-year record.
Precipitation was above average across much of the western Plains and West and in parts of the Southeast and New England. Precipitation was below average from the Mississippi River Valley to the Mid-Atlantic and southern New England, and in parts of the Northwest and central Rockies.
Across the state of Alaska, the average monthly precipitation was 2.98 inches, making last month the fourth-wettest May in the 99-year record. Conditions were wetter than average across most of the state while parts of the Southeast were record wettest. Near-average precipitation was observed in parts of the Aleutians and the Panhandle during the month.
According to the May 30 U.S. Drought Monitor, about 19.0% of the contiguous U.S. was in drought, down about 5.4% from the beginning of May. Drought conditions expanded or intensified in parts of the Midwest, Mid-Atlantic and central Plains this month. Drought contracted or was reduced in intensity across western parts of the Great Plains, the Florida peninsula, parts of the West and in western Puerto Rico.
Billion-Dollar Weather and Climate Disasters
There have been nine confirmed weather and climate disaster events, each with losses exceeding $1 billion this year. These disasters consisted of seven severe storm events, one winter storm and one flooding event. The total cost of these events exceeds $23 billion, and they have resulted in 99 direct and indirect fatalities.
The U.S. has sustained 357 separate weather and climate disasters since 1980 where overall damages/costs reached or exceeded $1 billion (including CPI adjustment to 2023). The total cost of these 357 events exceeds $2.540 trillion.
Other Notable Events
Millions of people were placed under heat advisories as a heat wave brought record-breaking temperatures to parts of the Northwest during mid-May. Temperatures reached 89°F in Seattle and 92°F in Portland, setting daily records in both cities.
Over March-May 2023, less than two inches of rain fell over parts of eastern Nebraska, resulting in the driest spring season conditions for the region since 1934 during the Dust Bowl.
Drought coverage in the contiguous U.S. has dropped nearly 44% over the last seven months, from 63% on October 25, 2022 to 19% on May 30, 2023—the fastest reduction in drought coverage since the start of the U.S. Drought Monitor (since 2000), and the smallest drought footprint since May 26, 2020.
Several notable weather systems produced severe thunderstorms and tornadoes that impacted portions of the U.S. in May:
- On May 7, a line of severe thunderstorms moved into southern Indiana and northern Kentucky. A total of six tornadoes was confirmed by the National Weather Service, five of which occurred within a 15-minute span.
- A tornado outbreak occurred across areas of central Oklahoma on May 11. The National Weather Service confirmed a total of nine tornadoes, which snapped utility poles and damaged homes.
- On May 12, severe thunderstorms produced several tornadoes, up to grapefruit-sized hail and flooding in parts of Nebraska. A total of 19 tornadoes, including three rated as EF-2, was confirmed by the National Weather Service.
On May 18, a cold front caused temperatures to drop to record lows across parts of the Northeast:
- Saranac Lake, New York temperature dipped to 17°F, crushing the previous record daily low of 24°F set back in 1983.
- Lebanon, New Hampshire temperature dropped to 23°F, beating out the old record of 27°F set in 1983.
- Montpelier, Vermont temperature dipped to 25°F, breaking the previous record of 27°F set in 1983.
- Trenton, New Jersey temperature fell to 37°F, breaking the old record of 38°F set in 2003.
During late April and early May, spring melting of record winter snowpack caused the Mississippi River to crest, resulting in near-record flooding in cities along the Mississippi River in Minnesota, Wisconsin and Iowa.
A coastal low brought rainfall of up to five inches and over 50 mph wind gusts to the Carolina coast over the Memorial Day weekend. The low also brought rainfall and thunderstorms to much of the Southeast.
The meteorological spring (March-May) average temperature for the contiguous U.S. was 51.5°F, 0.6°F above average, ranking in the middle third of the record.
Temperatures were above average from the southern Plains and Great Lakes to the East Coast and in parts of the Northwest. Temperatures were below average from parts of the West Coast to the northern Plains.
The contiguous U.S. average maximum (daytime) temperature during March-May was 63.7°F, 0.5°F above the 20th century average, ranking in the middle third of the historical record. Above-average temperatures were observed across much of the eastern contiguous U.S. and in parts of the Northwest, Southwest and central and southern Plains. Near- to below-average temperatures were observed from the West Coast to the northern Plains and in parts of the southern Plains and Southeast. Florida ranked seventh warmest while Massachusetts and Connecticut ranked ninth warmest, with two additional states experiencing a top-10 warmest March-May for daytime temperatures. No state experienced a top-10 coldest May on record for this three-month period.
The contiguous U.S. average minimum (nighttime) temperature during this three-month period was 39.3°F, 0.6°F above the 20th century average, ranking in the middle third of the historical record. Above-average nighttime temperatures were observed across much of the southern Plains to Southeast, Northeast and in parts of the Northwest, Mississippi River Valley and Great Lakes. Near- to below-normal temperatures were observed from California to the northern Plains and in parts of the central Plains and Great Lakes. Florida ranked fifth warmest on record for nighttime temperatures, while no state experienced a top-10 coldest event for nighttime temperatures this spring season.
The Alaska spring temperature was 23.3°F, 0.7°F above the long-term average, ranking in the coldest third of the record for the state. Temperatures were below average across much of interior Alaska and in parts of the west, southwest and Panhandle, while parts of the North Slope and Aleutians saw above average spring temperatures.
Based on REDTI, the contiguous U.S. temperature-related energy demand during March-May was 75 percent of average and was the 34th-lowest value on record.
The contiguous U.S. spring precipitation total was 7.86 inches, 0.08 inch above average, ranking in the middle third of the March-May record.
Precipitation was above average from the West Coast to the Rocky Mountains, and in parts of the western Plains, northern Great Lakes and Southeast.
Spring precipitation was below average from the central Plains to the Mid-Atlantic and in parts of the central and northern Rockies, as well as Maine during the March-May period. Pennsylvania and Maryland each ranked ninth driest while Kansas ranked 13th driest on record for the spring season.
For spring season precipitation, Alaska ranked in the middle third of the record with wetter-than-average conditions observed across most of the state. Precipitation was near average in parts of south-central Alaska and along the Gulf of Alaska coast.
The U.S. Climate Extremes Index (USCEI) for the spring period was 44 percent below average, ranking 13th lowest for the March-May period in the 114-year period of record. The USCEI is an index that tracks extremes (occurring in the upper or lower 10 percent of the record) in temperature, precipitation and drought across the contiguous United States.
On the regional scale, no region experienced an eleveted extreme this March-May period. Conversely, the Northeast and Upper Midwest were 96 percent and 73 percent below average ranking as their first and fourth lowest spring period on record, respectively.
For the January-May period, the average contiguous U.S. temperature was 45.2°F, 1.9°F above average, ranking 18th warmest on record for this period.
Temperatures were above average across much of the eastern U.S. and parts of the Northwest, with near- to below-average temperatures from the northern Plains to the West Coast.
Florida ranked warmest on record while Massachusetts, Rhode Island, Connecticut , New Jersey, Delaware and Maryland each had their second warmest January-May period. An additional 22 states had a top-10 warmest year-to-date period. No state experienced a top-10 coldest event for this five-month period.
The contiguous U.S. average maximum (daytime) temperature during January-May was 56.6°F, 1.7°F above the 20th century average, ranking in the warmest third of the historical record. Above-average temperatures were observed across much of the eastern contiguous U.S. and in parts of the Northwest. Near- to below-average temperatures were observed from the northern Plains to the West Coast. Florida ranked warmest on record while Massachusetts, Connecticut, Rhode Island, Pennsylvania, New Jersey, Maryland, Delaware, and Virginia each ranked second warmest on record for daytime temperatures during January-May period, while 19 additional states ranked among their top-10 warmest January-May on record for daytime temperatures. No state experienced a top-10 coldest May on record for this five-month period.
The contiguous U.S. average minimum (nighttime) temperature during this five-month period was 33.8°F, 2.1°F above the 20th century average, ranking 15th warmest in the historical record. Above-average nighttime temperatures were observed across much of the eastern contiguous U.S. and along parts of the Northwest and northern Plains. Florida and North Carolina ranked second warmest on record, while New Hampshire, Massachusetts, Connecticut, Rhode Island, New Jersey, New York, and Virginia each ranked third warmest on record for nighttime temperatures. 21 additional states experienced a top-10 warmest event for nighttime temperatures during the January-May period. Nighttime temperatures were near- to below-average from the West Coast to the Rockies and in other parts of the northern Plains.
The Alaska January-May temperature was 17.4°F, 1.6°F above the long-term average, ranking in the middle third of the historical record for the state. Much of the state was near-normal for the five-month period while temperatures were above average across much of the North Slope and in parts of the southeast, Kodiak Island and the Aleutians.
Based on REDTI, the contiguous U.S. temperature-related energy demand during January-May was 32 percent of average and was the fourth-lowest value on record.
The January-May precipitation total for the contiguous U.S. was 12.82 inches, 0.43 inch above average, ranking in the middle third of the 129-year record.
Precipitation was above average across much of California and the Southwest, and in parts of the southern Mississippi Valley, Southeast, northern Plains and Great Lakes. Utah and Nevada ranked 11th and 13th wettest on record, respectively.
Conversely, precipitation was below average across much of the Mid-Atlantic and in parts of the Northwest and central Plains during the January-May period. Maryland ranked fifth driest while Pennsylvania ranked 12th driest on record for this five-month period.
The January-May precipitation ranked in the wettest third of the 99-year record for Alaska, with above-average precipitation observed across much of the eastern Interior, North Slope, West Coast and in parts of the Panhandle. The central Interior and parts of the Southwest and Southeast were near average while south central Alaska and parts of the Aleutians experienced below-average precipitation during this period.
The U.S. Climate Extremes Index (USCEI) for the year-to-date period was 11 percent above average, ranking in the middle third of the 114-year period of record. Extremes in warm maximum temperatures and warm minimum temperatures were the major contributors to this elevated CEI value. The USCEI is an index that tracks extremes (occurring in the upper or lower 10 percent of the record) in temperature, precipitation and drought across the contiguous United States.
On the regional scale, the Northeast, Ohio Valley and Southeast ranked much-above average for this year-to-date period. Each of these regions experienced elevated extremes in warm maximum temperatures and warm minimum temperatures. Conversely, extremes across the Northwest were 99 percent below average while the Northern Rockies and Plains were 70 percent below average ranking second and fourth lowest year-to-date period on record, respectively.
According to the May 31 One-Month Outlook from the Climate Prediction Center, areas from the Northwest to the Ohio River Valley and into the Northeast, along the Gulf Coast and from northern Alaska to the Panhandle favor above-normal monthly average temperatures in June, with the greatest odds in Washington and parts of the northern Plains. The best chances for below-normal temperatures are forecast from southern California to the central Rockies and in parts of southwest Alaska. Much of the Northwest to southern Plains, as well as parts of Florida and southwest Alaska, are favored to see above-normal monthly total precipitation. Below-normal precipitation is most likely to occur from the northern Plains to the Great Lakes and in the interior parts of central and eastern Alaska. Drought improvement or removal is forecast across much of the Plains and portions of the northern Rockies and Florida, while persistence is more likely in portions of the Northwest, Southwest and parts of the central Plains and northwest Puerto Rico. Drought development is likely from the middle Mississippi Valley to parts of the Northeast and in parts of Hawaii.
According to the One-Month Outlook issued on June 1 from the National Interagency Fire Center, portions of the Northwest, northern Great Lakes and eastern Alaska have above-normal significant wildland fire potential during June, while portions of California and the Southwest are expected to have below-normal potential for the month.
These regional summaries were provided by the six Regional Climate Centers and reflect conditions in their respective regions. These six regions differ spatially from the nine climatic regions of the National Centers for Environmental Information.
Northeast (Information provided by the Northeast Regional Climate Center)
May was spring's only cooler-than-normal month and featured record or near-record dryness in several locations.
The Northeast's May average temperature of 55.3 degrees F was 1.7 degrees F cooler than normal. State average temperature departures ranged from 2.7 degrees F below normal in West Virginia to exactly normal in Maine. The Northeast had its 19th warmest spring with an average temperature of 46.9 degrees F, 1.1 degrees F warmer than normal. Spring average temperature departures for the 12 Northeast states ranged from 0.2 degrees F below normal in West Virginia, the sole cooler-than-normal state, to 2.0 degrees F above normal in Maine. This spring ranked among the 20 warmest since records began in 1895 for eight states: Massachusetts, 10th warmest; Delaware and Rhode Island, 11th warmest; Connecticut, 13th warmest; New Hampshire, 14th warmest; Maine and Maryland, 15th warmest; and New Jersey, 16th warmest.
The Northeast saw 2.70 inches of precipitation during May, which was 68 percent of normal. Ten of the 12 Northeast states were drier than normal, with precipitation for all states ranging from 42 percent of normal in Pennsylvania to 113 percent of normal in Maine. This May ranked among the 20 driest on record for three states: Pennsylvania, fifth driest; Maryland, eighth driest; and New York, 18th driest. May 2023 was the driest May since recordkeeping began for five major climate sites: Wilmington, Delaware; Binghamton, New York; and Philadelphia, Harrisburg, and Williamsport, Pennsylvania, with each seeing less than 0.75 inches of precipitation. Three major climate sites also had their greatest number of May days with no measurable precipitation, with 28 days at Harrisburg and 26 days at Williamsport and Binghamton. During spring, the Northeast received 9.19 inches of precipitation, 81 percent of normal. All twelve states were drier than normal, with spring precipitation ranging from 65 percent of normal in Maryland to 95 percent of normal in Connecticut and New Hampshire. This spring was among the 20 driest on record for three states: Maryland and Pennsylvania, ninth driest, and West Virginia, 18th driest.
The U.S. Drought Monitor from May 2 showed 1 percent of the Northeast in moderate drought and 9 percent as abnormally dry. During May, much of the Northeast saw below-normal precipitation, leading to little soil moisture, low streamflow, and declining groundwater levels. Moderate drought expanded in Maryland and eastern Pennsylvania, while there was a widespread expansion of abnormal dryness across the Northeast. The main exception was southern New England, which saw some improvement during the month. The U.S. Drought Monitor from May 30 showed 2 percent of the Northeast in moderate drought and 47 percent as abnormally dry. During May, particularly at month's end, record low 7-day streamflow was noted in multiple parts of Maryland, Delaware, New Jersey, Pennsylvania, and New York. Similarly, record low groundwater levels were measured in several areas including southern/eastern Pennsylvania, central Maryland, and central New York. Warm, dry conditions contributed to an increased risk of wildfires, with multiple fires in states such as Pennsylvania, New York, and New Jersey. Due to dry conditions, Pennsylvania farmers began irrigating crops, with some growers concerned about crop losses.
An upper-level low pressure system that had stalled near the region in late April finally meandered away during the first few days of May but continued to bring persistent below-normal temperatures and rounds of precipitation during that time. In fact, a rare May snow event occurred in some higher-elevation locations of West Virginia and southwestern Pennsylvania. The greatest storm snow total reached 20.3 inches in Davis, West Virginia, ranking as West Virginia's largest May snowstorm and the snowiest May for any West Virginia site on record. Davis saw 10.1 inches of snow on May 3, ranking as the greatest daily snowfall for May for any West Virginia site. Meanwhile, Snowshoe, West Virginia, had its snowiest May since records began in 1975 with 16.0 inches and its snowiest May day with 7.0 inches on May 3. The site's snow depth of 15 inches on May 4 was the greatest May snow depth on record for any West Virginia site. The event was also notable even at sites that saw less snowfall, such as Donegal, Pennsylvania, which had its snowiest May since records began in 1945 with 0.7 inches of snow. In addition, on May 1, a storm system associated with the upper-level low set record-low sea level pressures for May at least eight sites including Boston, Massachusetts; Williamsport, Pennsylvania; and New York City. Low temperatures on May 18 bottomed out in the 20s and 30s in multiple parts of the Northeast, running as much as 22 degrees F colder than normal. For instance, lows of 30 degrees F in Scranton, Pennsylvania, and 33 degrees F in Providence, Rhode Island, ranked among the 10 coldest low temperatures for May at those sites. After a mild April, some crops were ahead of schedule, leaving them particularly susceptible to the unusually cold temperatures. There was widespread frost/freeze damage to grape vines, particularly in central and eastern New York where early estimated losses of 70 to 100 percent of some grape varietals were reported at some vineyards. Early estimates indicate around a third of Massachusetts' apple crop was damaged, while preliminary estimates from New Hampshire indicate damages to the state's apple crop could exceed $1 million. Vermont officials reported severe damage to thousands of acres of crops, while Connecticut officials also have reported significant crop losses. The full extent of damage will take more time to assess. On nearly half of all May days, smoke from wildfires burning in western Canada, transported by the jet stream, created hazy skies in parts of the Northeast. On May 30 and 31, smoke from wildfires in eastern Canada and New Jersey led to reduced air quality in parts of the Mid-Atlantic. Not only did this May rank as the driest or among the driest Mays on record for several sites, it also ranked among the 10 all-time driest months on record at six major climate sites: Wilmington, Delaware; Binghamton, New York; and Philadelphia, Harrisburg, Williamsport, and Allentown, Pennsylvania. May was unusually quiet in terms of severe weather. For the first time in over 35 years, no Severe Thunderstorm Warnings were issued during May by the Mount Holly/Philadelphia, Washington/Baltimore, or Pittsburgh National Weather Service (NWS) offices. In addition, it was the first time since 1999 that the Albany NWS office did not issue any Severe Thunderstorm Warnings between January and May. May also brought an end to the 2022-23 snow season, which runs from October through May. Six major climate sites had their least snowy season on record: Beckley, West Virginia; Bridgeport, Connecticut; Central Park, New York; Dulles Airport, Virginia; Baltimore, Maryland; and Atlantic City, New Jersey. Seasonal snowfall deficits at these sites ranged from 17.1 inches below normal in Atlantic City, which saw only 0.3 inches of snow this season, to 44.4 inches below normal in Beckley, which accumulated only 11.5 inches this season.
For more information, please visit the Northeast Regional Climate Center Home Page.
Midwest Region (Information provided by the Midwest Regional Climate Center)
The average May temperature for the Midwest was 60.7 degrees F (15.9 degrees C), which was 1 degree F (0.6 degrees C) above the 1991-2020 normal. Average temperatures in the far eastern region were slightly below normal, while areas west of the Mississippi River were up to 9 degrees F (5 degrees C) above normal. Maximum and minimum temperatures followed a similar west-to-east spatial pattern. Preliminary statewide average temperatures ranged from 2 degrees F (1.1 degrees C) below normal in Ohio to 4.4 degrees F (2.4 degrees C) above normal in Minnesota. Preliminary rankings indicate Minnesota was tied for the 6th warmest May since 1895. No monthly average, maximum, or minimum temperature records were broken among long-running stations across the Midwest in May. Three stations in Minnesota ranked in the top ten warmest for May, including Minneapolis-St. Paul, which recorded the 6th warmest May in 151 years. The average spring (March-May) temperature for the Midwest was 0.2 degrees F (0.1 degrees C) below normal, with most areas near to slightly above normal, except in Minnesota, where temperatures were up to 4 degrees F (2.2 degrees C) below normal for spring.
May precipitation totaled 2.56 inches (65 mm) for the Midwest, which was 1.82 inches (46 mm) below normal, or 59 percent of normal. Based on preliminary rankings, the Midwest was tied for the 11th driest May since 1895. All nine Midwestern states measured below-normal precipitation, with totals ranging from 1.15 inches (29 mm) below normal in Minnesota to 2.24 inches (57 mm) below normal in Missouri. Preliminary rankings indicate the 6th driest May on record for Wisconsin, with statewide precipitation at 45 percent of normal for the month. Most of the region had precipitation ranging from 10-75 percent of normal for May, and many stations ranked in the top ten driest for the month. Murry, Kentucky, had the driest May in 94 years, with 0.41 inches (10.4 mm) of precipitation. Ashland, Wisconsin, had the driest May in 113 years with 0.31 inches (7.9 mm). Still, localized thunderstorms produced isolated areas with near- to above-normal precipitation. For instance, Comfrey, Minnesota, had over 10 inches (254 mm) of precipitation, which was nearly 6 inches (152.4 mm) above normal for May. Southern Minnesota and Michigan's Upper Peninsula were two locations where 100-175 percent of normal precipitation spanned multiple counties. Spring (March-May) precipitation for the Midwest totaled 8.72 inches (221.5 mm), which was 1.9 inches (48.3 mm) below normal. The driest area in the region spanned from central Missouri northward through Iowa, where precipitation departures were 4-9 inches (101.6 - 228.6 mm) below normal for spring.
Rapid drying occurred across much of the Midwest throughout May due to the combined effects of below-normal precipitation and an unusually dry atmosphere (low humidity). By month's end, abnormal dryness and drought spread across two-thirds of the Midwest and affected all nine states in the region. Drought was widespread in Missouri, with 50 percent of the state in moderate to extreme drought and 30 percent depicted as abnormally dry. Missouri's Governor declared a Drought Alert on May 31 as farmers and ranchers reported high demand for hay and low forage quality. Persistent drought conditions prompted water restrictions in western Iowa. Low atmospheric humidity, low rainfall, and a delayed spring green-up increased fire risk, prompting the National Weather Service to issue two dozen Red Flag warnings throughout the month in northern Minnesota and northwest Wisconsin.
Air Quality: Historically large wildfires in Alberta, Canada, brought smoky and hazy conditions to the Midwest starting in early May that persisted throughout the month. As the smoke settled in, repeated air quality alerts were issued across multiple Midwestern states, with the greatest number of alerts issued in Minnesota and Wisconsin. Record May Snowfall in the Upper Peninsula: A stalled low-pressure system from late April lingered around the Great Lakes region at the start of May, bringing heavy snowfall to Michigan's Upper Peninsula and light snow to eastern Wisconsin. Herman, Michigan, recorded a storm total (April 29-May 2) snowfall of 52 inches (132.1 cm), with a single-day snowfall total of 27 inches (68.6 cm) on May 2. According to the National Weather Service in Marquette, Herman set a new record for the greatest one-day May snowfall east of the Mississippi River. Herman also achieved its snowiest May on record with 48 inches (121.9 cm), beating the previous record by 22 inches (55.9 cm). May 1 Dust Storm: Strong winds (gusting up to 54 mph/87 kph) moved across freshly plowed fields on May 1, resulting in an isolated but significant dust storm over a two-mile stretch of Interstate 55 near Springfield, Illinois. Near-zero visibility led to a 72-vehicle crash that resulted in 7 fatalities and 37 injuries.
For further details on the weather and climate events in the Midwest, see the weekly and monthly reports at the Midwest Climate Watch page.
Southeast (Information provided by the Southeast Regional Climate Center)
Mean temperatures in May were below average across much of the Southeast region. The greatest departures were found across Virginia and the Carolinas, where some locations were 3 to 5 degrees F (1.6 to 2.8 degrees C) below average for the month. Concord, NC, located just northeast of Charlotte, recorded its coldest May on record (since 1933), while Asheboro, NC, located in the middle of the state, recorded its second coldest May on record (since 1926). In contrast, mean temperatures were near average across southern portions of Alabama and Georgia, and above average across much of Florida, Puerto Rico and the U.S. Virgin Islands, where some locations were 2 to 3 degrees F (1.1 to 1.6 degrees C) above average. Fort Myers, FL recorded its second warmest May on record (since 1902). The month began with unseasonably cool weather, with mean temperatures between 5 and 10 degrees F (2.8 and 5.6 degrees C) below average in many places. Temperatures dropped below freezing across western North Carolina on the morning of the 4th. Warm weather returned on the 8th of the month, with mean temperatures between 5 and 10 degrees F (2.8 and 5.6 degrees C) across much of the region. Mobile, AL reached 95 degrees F (35 degrees C) on the 16th of the month, which tied for the third earliest such day since 1871, missing the record by just five days (May 11, 1916). Slightly cooler than average temperatures returned to most of the region by the 18th of the month, while warm weather persisted across Florida. The passage of a cold front on the 24th and 25th resulted in temperatures between 10 and 20 degrees F (5.6 and 11.1 degrees C) below average across much of the region, especially in Georgia and the Carolinas. This was followed by more unseasonably cool weather from the 26th to the 30th, as clouds and precipitation attending a low pressure system slowly drifted inland.
Precipitation was variable across the Southeast in May. Generally above average precipitation (125 to 150 percent of normal) was observed along the tracks of a few low pressure systems and where frontal boundaries stalled across the region. These included locations extending across central and southern Alabama, Georgia, and South Carolina, coastal sections of North Carolina and Virginia, as well as the northern Peninsula of Florida, where monthly precipitation was 150 to 300 percent of normal. Fernandina Beach, FL, located near Jacksonville, recorded its second wettest May on record (since 1892) with 10.64 inches (270 mm) of precipitation, while Talladega, AL recorded its third wettest May on record (since 1888) with 10.12 inches (257 mm) of precipitation. Many of the above average monthly precipitation totals were tied to particularly high daily and hourly totals. Fernandina Beach, FL recorded 7 inches (178 mm) of precipitation on the 23rd, which is the greatest one-day total for any May day on record. Orlando, FL recorded 3.90 inches (99 mm) on the 18th, which is the second greatest one-day total in May on record (since 1892). Of this, 3.04 inches (77 mm) fell in just one hour, which ranks as the second highest one-hour total since 1952. Wilmington, NC recorded 4.15 inches (105 mm) on the 19th, which is the fourth greatest one-day total in May on record (since 1871). Richmond, VA also recorded its fourth greatest one-day total in May (since 1871) with 2.78 inches (71 mm) on the 16th. Ponce, PR recorded its fifth greatest one-day total in May (since 1899) with 3.85 inches (98 mm) on the 22nd. In contrast, monthly precipitation was below average (less than 75 percent of normal) across northern and interior sections of the region, as well as much of South Florida, Puerto Rico, and the U.S. Virgin Islands. Harrisonburg, VA, located in the Shenandoah Valley, recorded 0.85 inches (21 mm) of precipitation (20 percent of normal), making it the fourth driest May on record (since 1893). Henry Rohlsen Airport on the island of Saint Croix continued its stretch of dry weather with just 0.34 inches (8.6 mm) of precipitation (10 percent of normal), making it the third driest May and third driest start to the year (53 percent of normal) since 1951. Wintry precipitation was observed across western portions of Virginia and North Carolina from the 1st to the 4th. Most reports were for trace amounts of snow and ice pellets, though there were a few reports of 3 to 7 inches (76 to 178 mm) of snow across extreme western Virginia (above 2,500 feet or 762 m).
Drought conditions improved across much of the region in May. Overall, less than 10 percent of the region was in abnormally dry (D0) conditions by the end of the month (down by about 5 percent from April), while moderate (D1) to severe (D2) drought covered about 3 percent of the region (down by about 14 percent from April). Improvements of one to two drought categories were noted across northern Virginia and the Florida Peninsula, including an improvement from extreme (D3) to severe (D2) drought in west-central Florida and removal of moderate (D1) drought along the Space Coast. Abnormally dry (D0) conditions were eliminated across Alabama, while just a few pockets remained across Georgia and the Carolinas. Drought conditions also improved across western portions of Puerto Rico, while abnormally dry (D0) conditions emerged to the east and along some of the outlying islands. The continued dryness, warm temperatures, and high winds contributed to further intensification of drought in the U.S. Virgin Islands. All three islands observed a one category degradation in May, with moderate (D1) drought on Saint John, severe (D2) drought on Saint Thomas, and extreme (D3) drought on Saint Croix by the end of the month. This marks the first time that extreme (D3) drought has been observed in the Caribbean region since February 2016.
Generally dry weather allowed farmers ample time for fieldwork, though progress was slowed in areas that experienced higher precipitation totals. Corn planting and emergence were completed with much of the crop entering the silking and tasseling phases by the end of the month. The planting and emergence of cotton, peanuts, and soybeans were delayed in many places due to cool temperatures and reduced soil moisture, though conditions became more favorable during the latter half of the month. Heavier precipitation across southern Georgia prevented seed emergence and forced some farmers to replant cotton and peanuts. Cooler weather and freezes earlier in the year delayed the harvest of winter wheat in parts of Alabama and South Carolina. Hay production was also slowed by cool and dry weather, particularly in Georgia and South Carolina. Cattle and pastures were in generally good condition across much of the region. Cooler temperatures helped reduce stress in cattle, while pasture and forage conditions improved in places that received much-needed precipitation, particularly across the Florida Peninsula. Warm weather in February followed by a few spring freezes have severely impacted the peach crop. Delays in harvest along with widespread bacterial diseases were reported in South Carolina, while producers in Georgia are expecting only 5 percent of the normal yield to be harvested this year. Fungal diseases were also noted on blueberries, strawberries, watermelons, and cantaloupes, resulting in losses across parts of Georgia, South Carolina, and Florida. Below average precipitation, warm temperatures, and high winds have contributed to dry pastures across western Puerto Rico and the U.S. Virgin Islands.
There were 291 reports of severe weather across the Southeast in May, which is below the median frequency of 453 reports over the period 2000 to 2022 (64 percent of normal). There were five confirmed tornadoes (2 EF-0s, 3 EF-1s), which is below the median frequency of 11 (45 percent of normal). On the 7th of the month, an EF-0 briefly touched down in Henderson County in western North Carolina, marking the first confirmed tornado in the county since 1977. Several trees were uprooted and snapped while a few structures sustained minor damage. On the 9th of the month, an EF-1 briefly touched down in Scott County in extreme southwestern Virginia, uprooting trees near the community of Duffield. Another two EF-1 tornadoes touched down in neighboring Lee County on the 16th of the month, uprooting trees near the town of Pennington Gap. On the 25th of the month, an EF-0 touched down in Miami-Dade County, FL not far from Zoo Miami. A tractor trailer was knocked on its side, injuring the driver. There were 218 wind reports in May, which is below the median frequency of 300 (73 percent of normal). On the 9th of the month, thunderstorm winds approaching 80 mph (36 m/s) brought down trees and damaged sailboats in Charleston Harbor. The thunderstorm complex that contributed to the tornadoes in Lee County, VA on the 16th of the month also produced straight-line winds between 70 and 90 mph (31 and 40 m/s). Another supercell thunderstorm later that evening produced winds up to 85 mph (38 m/s) across Gaston County just west of Charlotte, NC. The most significant damage occurred in the town of Cherryville, where numerous trees were uprooted and snapped and at least one home had its roof ripped off. One person was injured after being thrown in the air by a fallen tree while helping rescue passengers trapped in a car. Other notable wind events included a 66 mph (30 m/s) wind gust on Mount Mitchell, NC on the 3rd and a 69 mph (30 m/s) wind gust at the Whiting Field Naval Air Station near Pensacola, FL on the 15th of the month. There were 68 hail reports in May, which is below the median frequency of 142 (48 percent of normal). The largest hailstone was tennis ball-sized, or 2.5 inches (64 mm), near the town of Ellenton in Colquitt County in southern Georgia on the 11th of the month. A hailstone measuring 2.25 inches (57 mm) was reported in Greenville County, SC on the 9th of the month. This is the seventh largest hailstone recorded in the county since 1950. A strong low pressure system off the Southeast coast contributed to rough seas over the Memorial Day weekend. Numerous rip current rescues were reported along the Outer Banks of North Carolina. A man died after being thrown from a boat in rough waters along the Cape Lookout National Seashore on the 28th of the month. A Carnival cruise ship took on water and sustained significant damage while attempting to reach port in Charleston Harbor on the 27th. Some passengers and crew members sustained minor injuries. There was one rip current fatality in the Southeast in May. A 52-year-old male drowned in Punta Salinas, PR on 27th. There was also one lightning fatality in the region. A 24-year-old man was struck while working on a rooftop in Volusia County, FL on 22nd of the month.
For more information, please visit the Southeast Regional Climate Center Home Page.
High Plains (Information provided by the High Plains Regional Climate Center)
The phrase, “when it rains, it pours” would describe the month of May for northwestern Kansas and southwestern Nebraska. Parts of the area had gone nearly 290 days without over 0.5 inches (12.7 mm) of precipitation in a day to nearly 7.5 inches (19.05 cm) in a single day. Other places in the region like eastern Nebraska, have not been as fortunate, with near-record dryness this month and the entire spring. The town of Culbertson in southwestern Nebraska recorded its driest year on record in 2022, with a meager 10.87 inches of precipitation (27.61 cm). In the month of May, they recorded nearly the same amount as the whole year of 2022, with 10.65 inches of precipitation (27.05 cm). While the complete reversal has greatly improved drought conditions, long-term drought impacts still plague the area. These rains are also too late to improve winter wheat yields for the year, with yields projected to be among the worst in the past 60 years. This spring was incredibly dry across eastern Nebraska, with corn struggling to emerge. Widespread irrigation is taking place rather early in the season, due to insufficient precipitation. This dryness is not short-term, with multiple locations recording their driest past 12 months.
Temperatures were above-to-well above-normal for the region, with departures over 8 degrees F (4.4 degrees C) above-normal in parts of the Dakotas. Many locations ranked in the top 5 warmest after the unseasonably warm temperatures. The Dakotas were unusually warm, with many locations observing near-record warmth this month. In North Dakota, Grand Forks and Fargo were the 2nd warmest on record while Williston and Dickinson both tied for 6th. Grand Forks surpassed 80 degrees F (26.7 degrees C) for the first time in 241 days on May 13th, marking the end of the cooler temperatures in the state. South Dakota had Sisseton, Mobridge, and Sioux Falls all rank in the top 5 warmest. Parts of Wyoming and western Nebraska were also warmer this month, with Laramie and Cheyenne in the top 5 warmest. Portions of Yellowstone National Park reached nearly 90 degrees F (32.2 degrees C), which is their record high temperature for May. Nearby Nebraska had Chadron and Scottsbluff in the top 10 warmest this past month.
May precipitation was above normal for eastern Colorado, western Kansas and Nebraska, and parts of the Dakotas. The eastern part of the region was bone dry, with places 25 percent below normal. Eastern Nebraska was dry not only this past month but the entire Spring. For the month of May, Omaha was the driest on record with only 0.17 inches (4.06 mm) of precipitation. This has broken the previous low of 0.55 inches (13.97 mm) set in 1989 and 1925 by a large margin. Lincoln was 0.02 inches (0.51 mm) from ranking driest, with only 0.51 inches this past month. Looking further back, Norfolk observed their driest spring with 2.41 inches (6.12 cm) of precipitation. Hastings and Lincoln were not far behind, ranking 3rd. The dryness plaguing the area also stretches much further back, with Hastings, Lincoln, and Norfolk all having their driest past 12 months. A continuous onslaught of storms impacted the Front Range into the western parts of Kansas and Nebraska. McCook, Nebraska observed not only their wettest May, but also their wettest month on record with 10.94 inches (27.79 cm). Nearby CoCoRaHS observers reported amounts up to 14 inches (35.56 cm), much more than they received in 2022. Nearby North Platte ranked 3rd wettest, while Chadron ranked 5th. In Colorado, Denver ranked 4th, and Colorado Springs ranked 6th wettest. Severe weather was active at the beginning of the month before calming down. Multiple days featured several tornadoes and 4+ inch (10.16 cm) hail, with the peak on the 12th of the month in Nebraska. 19 tornadoes were reported, with three being rated EF-2, with one having an estimated width of a mile (1.61 km). Numerous hailstone events were also reported that day. The largest hailstone with a size around 4.5 inches (11.43 cm) was reported near the town of Pawnee.
The region, for the most part, experienced improvements up to 3 classes this month thanks to constant precipitation. The areas that were dry observed up to a 2-class degradation such as eastern Nebraska and Kansas. Overall, moderate to exceptional drought (D1-D4) was reduced by 12 percent for the High Plains. Southwestern Nebraska experienced the most improvement this month, with some areas going from extreme drought (D3) to abnormally dry (D0). The eastern part of the state observed a large increase to both D3 and D4, in response to the dryness since the beginning of the year.
For more information, please visit the High Plains Regional Climate Center Home Page.
South (Information provided by the Southern Regional Climate Center)
Substantial improvement in drought conditions across the western portions of the region.
Temperatures were near to above normal for much of the Southern Region for the month of May. The largest departures from normal were observed in western Oklahoma with temperatures averaging 2-4 degrees F above normal and in the Big Bend area of Texas where temperatures averaged 4 to 5 degrees below normal for the month of May. Statewide averages for May were above normal for Louisiana (32nd warmest, out of 129 years), Texas (40th warmest), the Southern Region as a whole (43rd warmest), Mississippi 46th warmest) and Arkansas (46th warmest). Oklahoma and Tennessee were near their historical median values during May. The warmest recorded temperature in the region was 105 F at Rio Grande Village, Texas on May 31st. The coldest recorded temperature in the region was 24 F at Mt. Leconte, Tennessee on May 2nd. The coldest recorded lowland temperature was 32 F at Bartlesville, Oklahoma on May 3rd. Two long-term stations set records for lowest minimum temperatures during May: Brownsville, Tennessee (31 F) on May 2nd and Bolivar Water Works, Tennessee (29 F) on May 5th.
Precipitation was below normal for the much of the eastern and central portions of the region in addition to far west Texas. Precipitation was well above normal across central Texas, the Texas and Oklahoma panhandles, and in deep south Texas. Statewide average totals were below normal for Mississippi (36th driest), Louisiana (40th), Arkansas (44th), Oklahoma (44th), and the Southern Region as a whole (51st). The statewide average was above normal for Texas (40th wettest) and Tennessee was near its historical median value. Six stations exceeded eleven inches of accumulation for the month of May: near Gonzales, Texas (12.69 inches), near Nordheim, Texas (12.37), Palacios, Texas (12.01), near Saucier, Mississippi (11.90), Milan Experiment Station, Tennessee (11.12), and near Prague, Oklahoma (11.01). Three stations reported single daily rainfall accumulations of over six inches and were spread across two states: near Hot Springs, Arkansas (6.05 inches, May 11th), Palacios, Texas (6.21 inches, May 10th), and near Henderson, Texas (6.42 inches, May 11th). No long-term stations in the Southern Region set monthly records for daily accumulation in May.
During May the spatial extent and intensity of drought improved in many areas across the Southern region, particularly in the Texas Panhandle, central Texas, and western and central Oklahoma. Some areas in the Texas Panhandle saw as many as three categories of improvement, according to the US Drought Monitor. The percentage of the region experiencing moderate drought (D1) or worse decreased from 35 percent on May 2nd to 24 percent on May 30th. As of May 30th, western and north central Oklahoma, and isolated areas of central Texas are still experiencing extreme (D3) or exceptional (D4) drought conditions. The east of the region largely remained drought free, with two isolated areas of moderate drought along the southeast Louisiana coast being the exception. In Oklahoma and Texas, the drought conditions over time have impacted and continue to negatively impact agriculture, with only 28 percent of Texas cotton rating as good to excellent and winter wheat in Texas (23 percent good to excellent) and Oklahoma (30 percent as good to excellent). Despite overall poor conditions, improvements in crop and pasture conditions have been noted in recent weeks in these areas.
Twenty tornadoes were reported across the Southern Region in May, impacting the states of Oklahoma, Texas, Louisiana, and Arkansas. The ratings were 9 EF0, 10 EF1, and one EF2. On May 6th, an EF1 tornado near Morse, Louisiana led to one injury. On May 23rd, an EF2 tornado near Funston, Texas led to two injuries. There were no fatalities associated with tornadoes during May in the Southern Region. The largest of 300 hail reports in the region was a 3.3 inch hail near Morse, Texas on May 28th. There was a total of 325 severe wind reports, including a report of 90 MPH winds in New Hebron, Mississippi on May 5th that led to tree damage and damage to structures. Heavy rainfall in the Texas Panhandle during May led to several reports of flash flooding and flooded roadways during heavy rain events.
For more information, please visit the Southern Regional Climate Center Home Page.
West (Information provided by the Western Region Climate Center)
Strong high pressure persisted for much of May centered over central and southwest Canada bringing much above normal temperatures to all the Pacific Northwest and dry conditions to western Oregon and Washington. Several cutoff low-pressure systems moved through the Southwest bringing near-to-below normal temperatures and scattered areas of well above normal precipitation due to thunderstorm activity.
Several heat waves impacted the Pacific Northwest and northern Rockies in May driving record high monthly temperatures (4-8 degrees Fahrenheit above normal) for several major cities. Salt Lake City, Utah, Missoula, Montana, Boise, Idaho, Spokane, Washington, and Salem and Portland, Oregon all set new records for warmest May. One of the longest standings records to fall was at Spokane, Washington where the warmest May in 143 years occurred with a monthly mean temperature of 63.5 degrees Fahrenheit (7.5 degrees Fahrenheit above normal). Seattle, Washington saw its second warmest May and four days in a row (May 12-15) with record high daily temperatures all exceeding 80 degrees Fahrenheit. Cooler conditions and persistent “May grey” were found along the central and southern coast of California with temperatures generally 1-3 degrees Fahrenheit below normal.
May was much drier than normal across western Oregon, western Washington, and southeast Washington where precipitation totals were less than 50 percent of normal. Some locations saw record dryness such as Forks, Washington, on the Olympic Peninsula, where 0.59 inches of precipitation fell, just 11 percent of normal, for the driest May since records started in 1908. Portland, Oregon saw its 11th driest May with 0.91 inches of precipitation (36 percent of normal) and Eugene, Oregon saw its fifth driest May with 0.34 inches of precipitation (14 percent of normal). Drier than normal conditions also prevailed across northern Utah and northern Idaho. Several cutoff low-pressure systems produced widespread convective precipitation across the northern Great Basin and portions of southern California, Arizona, and New Mexico with wetter than normal conditions. Reno, Nevada recorded 2.44 inches of precipitation (444 percent of normal) for the second wettest May on record and Prescott, Arizona logged 1.72 inches of precipitation (337 percent of normal) for the fourth wettest May since records began in 1898.
According to the U.S. Drought Monitor at the end of May, 17 percent of the West was in drought. One tiny sliver of extreme drought (D3) remains in northeast New Mexico and no exceptional drought (D4) was present. One category drought improvements were found across Montana, far northern Idaho, and northeast New Mexico with expansion of drought or introduction of abnormal dryness (D0) in parts of Oregon and Washington.
Wetter than normal conditions prevailed across most of Alaska except for some isolated portions of the Interior, southern Panhandle, and northwest North Slope where conditions were drier than normal. May precipitation was 150-250 percent of normal for much of southwest Alaska. King Salmon received 2.99 inches of precipitation (208 percent of normal) for the seventh wettest May on record and Kodiak recorded 10.64 inches of precipitation (182 percent of normal) for the ninth wettest May on record. McGrath received 0.29 inches of precipitation (32 percent of normal) for the eighth driest May on record. May temperatures were below normal (1-2 degrees Fahrenheit) across western Alaska and above normal (1-3 degrees Fahrenheit) across the southern Panhandle and North Slope. On the Panhandle, Ketchikan saw a monthly mean temperature of 53.2 degrees Fahrenheit (3.1 degrees Fahrenheit above normal) and Sitka saw a monthly mean temperature of 50.1 degrees Fahrenheit (2.0 degrees Fahrenheit above normal) for the fifth and ninth warmest Mays on record, respectively.
Precipitation anomalies were mixed with mostly wetter than normal conditions across Kauai, O'ahu, and the Big Island with drier than normal conditions on Molokai, Maui, and the eastern shores of the Big Island. Lihue, on the island of Kauai, received 3.9 inches of precipitation in May, 179 percent of normal and the 12th wettest on record. Hilo, on the Big Island, recorded 5.46 inches of precipitation in May at 78 percent of normal. The U.S. Drought Monitor at the end of May showed 14 percent of the state in abnormally dry conditions (D0) and this was restricted to the islands of Maui and the Big Island. There were no areas of drought (D1-D4) present across the state.
Early season wildfire outbreak in Canada brings degraded air quality to parts of the West: Drought and early season heat waves have increased fire danger across Alberta, Canada and dozens of wildfires broke out in early May and have burned more than two million acres. Dense wildfire smoke has been drifting in and out of the West and primarily impacting Montana, Wyoming, and Colorado. On May 22, Denver, Colorado ranked in the top 20 cities across the world with worst air quality.
For more information, please go to the Western Regional Climate Center Home Page.