Issued 13 July 2015
Contents Of This Report:
Map showing Palmer Z Index
Percent Area of U.S. in Moderate to Extreme Drought, Jan 1996 to present
Climate Extremes Index for West Region, June, 1895-2015

Please note that the values presented in this report are based on preliminary data. They will change when the final data are processed, but will not be replaced on these pages.


National Drought Overview

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Detailed Drought Discussion


Overview


The weather and upper-level circulation during June 2015 was characterized by a long-wave ridge, which kept the western CONUS unusually warm and the Pacific Northwest and parts of Alaska drier than normal, and the North Atlantic subtropical high pressure center (Bermuda High), which helped keep the southeastern CONUS and Puerto Rico warmer and drier than normal. The storm track was squeezed in between these systems, bringing above-normal precipitation to the Midwest to Northeast, while monsoon showers were aided by moisture from eastern Tropical Pacific cyclones to bring above-normal precipitation to much of the Southwest. As a result, drought and abnormally dry conditions developed and expanded in the Northwest and parts of the Southeast and contracted in parts of the Southwest and from the Great Plains to Northeast. The drier-than-normal conditions across much of Alaska and Puerto Rico and parts of Hawaii prompted drought and abnormally dry conditions to expand in all three regions. When integrated across the CONUS, June 2015 ranked as the ninth wettest June in the 1895-2015 record, due largely to record and near-record rainfall in the Ohio Valley to Northeast. On balance, the national drought footprint expanded when compared to last month, increasing from 20.6 percent of the U.S. as a whole to about 23.3 percent of the U.S. in moderate to exceptional drought, according to USDM statistics. According to the Palmer Drought Index, which goes back to the beginning of the 20th century, about 20.2 percent of the CONUS was in moderate to extreme drought at the end of June, an increase of about 3.7 percent compared to last month.

The U.S. Drought Monitor drought map valid June 30, 2015
The U.S. Drought Monitor drought map valid June 30, 2015.

By the end of the month:

  • moderate (D1) to severe (D2) drought covered a large part of the western U.S., with extreme (D3) to exceptional (D4) drought extending from California and the Pacific Northwest into the Intermountain Basin;
  • pockets of moderate to severe drought developed or expanded in the Southeast, Hawaii, and Puerto Rico;
  • moderate drought developed in Alaska; and
  • pockets of moderate drought remained in parts of the Northern and Southern Plains and Northeast.
Percent area of the CONUS in moderate to exceptional drought, January 4, 2000 to present, based on the U.S. Drought Monitor
Percent area of the CONUS in moderate to exceptional drought, January 4, 2000 to present, based on the U.S. Drought Monitor.


Palmer Drought Index


The Palmer drought indices measure the balance between moisture demand (evapotranspiration driven by temperature) and moisture supply (precipitation). The Palmer Z Index depicts moisture conditions for the current month, while the Palmer Hydrological Drought Index (PHDI) and Palmer Drought Severity Index (PDSI) depict the current month's cumulative moisture conditions integrated over the last several months. While both the PDSI and PHDI indices show long-term moisture conditions, the PDSI depicts meteorological drought while the PHDI depicts hydrological drought. The PDSI map shows less severe and extensive drought in parts of the West than the PHDI map because the meteorological conditions that produce drought and wet spell conditions are not as long-lasting as the hydrological impacts.

Palmer Z Index map Palmer Hydrological Drought Index map

Used together, the Palmer Z Index and PHDI maps show that short-term dry conditions occurred over much of the Pacific Northwest and parts of the Southeast, resulting in expanding or developing long-term drought in June compared to May. Short-term wet conditions contracted drought in the Northeast and eastern Arizona, continued to expand long-term wet conditions in the Southern Plains, and were reflected in new long-term wet conditions in the Midwest, compared to last month.



Standardized Precipitation Index


The Standardized Precipitation Index (SPI) measures moisture supply. The SPI maps here show the spatial extent of anomalously wet and dry areas at time scales ranging from 1 month to 24 months.

1-month Standardized Precipitation Index 2-month Standardized Precipitation Index 3-month Standardized Precipitation Index

6-month Standardized Precipitation Index

The SPI maps illustrate how moisture conditions have varied considerably through time and space over the last two years. Dryness in the Pacific Northwest is evident at all time scales, but is most severe at the 1 to 6 month time scales. Near normal to slightly wet conditions are evident in California on the 1- to 3-month SPI maps, but April-June is part of the dry season, so above-normal precipitation at this time of year does not contribute much to California's hydrology. Dry conditions are evident for the state from the 6 to 24 month time scales. Wet conditions are evident for parts of the Southwest, especially the eastern sections, at most time scales, with dryness evident in the western sections at 9 months. The heavy rains of the last several months have eliminated dry conditions in the Southern Plains, with wet conditions prevailing at all time scales. Some dryness is evident in Kansas at 1 month, but near normal to wet conditions dominate at the other time scales in the Central Plains. In the Northern Plains, pockets of dryness are evident at 1 month and 6 to 24 months, but areas of wetness are also evident. In the Northeast, wetness dominates at the 1- to 3-month time scales, especially in the western sections, but dryness is evident in the eastern sections from 3 to 24 months. The Southeast has areas of dryness at 1 to 12 months, but especially at the 2-, 6-, and 12-month time scales.


9-month Standardized Precipitation Index 12-month Standardized Precipitation Index 24-month Standardized Precipitation Index



Standardized Precipitation Evapotranspiration Index


The SPI measures water supply (precipitation), while the SPEI (Standardized Precipitation Evapotranspiration Index) measures the combination of water supply (precipitation) and water demand (evapotranspiration as computed from temperature). Warmer temperatures tend to increase evapotranspiration, which generally makes droughts more intense.

1-month SPEI for current month
1-month SPEI for current month.
1-month SPI for current month
1-month SPI for current month.

Temperatures were below normal across the Southern Plains and Great Lakes to Northeast, and much above normal in the Southeast and across the West, during June 2015. The warmer-than-normal temperatures amplified the dry conditions in the Northwest when the 1-month SPEI is compared to the SPI. The combination of heat and dryness was so severe that Idaho and Oregon had the most severe SPEI for June in the 1895-2015 record, and Washington had the most severe SPEI on record for June and May-June. The June 2015 SPEI for all three states was much worse than the June 2015 SPI — Washington's June 2015 SPI was the fourth driest on record, while the SPI for Idaho and Oregon ranked further down in the top ten.

June SPEI for Idaho, 1895-2015
June SPEI for Idaho, 1895-2015.
2-month SPEI for Washington State, May-June, 1895-2015
2-month SPEI for Washington State, May-June, 1895-2015.

California statewide 48-month SPEI, July-June, 1895-2015
California statewide 48-month SPEI, July-June, 1895-2015.

Heavy rains in the Southern Plains during the last several months have been enough to make up the precipitation deficits of the last several years and pull the region out of drought at the 12-, 24-, and 36-month time scales, according to the SPEI. Some drought still shows up in Texas at the 48 to 60-month time scales. The opposite is true for much of the West which has had record to near-record warmth for the last six to 12 months, and longer. This has especially been the case for California, which has had a statewide temperature for the last 12 months that has far exceeded any July-June temperature in the state's 1895-2015 period of record. The California July-June temperatures for the last three years have been record or near-record warm. The unusual warmth has combined with the extreme dryness to produce record extreme SPEI values for the last 24, 36, 48, and 60 months. The 12-month SPEI (for July 2014-June 2015) ranked third driest behind 2013-14 and 2006-07. The record-warm temperatures in June gave California the fourth driest June SPEI, while precipitation, alone, gave the state an SPI a little on the wet side.

California statewide 12-month precipitation, July-June, 1895-2015
California statewide 12-month precipitation, July-June, 1895-2015.
California statewide 12-month temperature, July-June, 1895-2015
California statewide 12-month temperature, July-June, 1895-2015.


Agricultural, Hydrological, and Meteorological Indices and Impacts

USDA topsoil moisture short to very short
USDA topsoil moisture short to very short
USGS monthly streamflow percentiles
USGS monthly streamflow percentiles

Drought conditions were reflected in numerous agricultural, hydrological, and other meteorological indicators, both observed and modeled.

The dryness of June 2015 was reflected in below-normal precipitation totals, few days with precipitation, and long runs of dry days, especially across the Pacific Northwest and parts of the Southeast. The lack of spring mountain snow cover and below-normal precipitation have resulted in widespread low stream levels and reduced groundwater levels across the West. The unusually hot temperatures in the West have increased evapotranspiration (Evaporative Stress Index, Evaporative Demand Drought Index) and contributed to low soil moisture, as seen both in modeled soil moisture content and U.S. Department of Agriculture (USDA) observations. The area of depleted soil moisture stretched from California and the Pacific Northwest, through Montana, and across the western Prairies of Canada. The USDA reported that, on June 28th, 90 percent of the topsoil in California was rated short or very short of moisture (dry or very dry). The statistics for other western states included: 69 percent in Oregon, 57 percent in Washington, 49 percent in New Mexico, 48 percent in Montana, and 40 percent in Idaho and Utah. The drought has stressed vegetation and impacted crops and pastures. The Crop Moisture Index showed deteriorating conditions across the West as the month progressed (June 6th, 13th, 20th, 27th). According to June 28th USDA reports, 29 percent of the winter wheat crop was in poor or very poor condition in Oregon, 15 percent in Washington, and 10 percent in Idaho; 18 percent of spring wheat was in poor or very poor condition in Washington; and 45 percent of pastures and range land was in poor or very poor condition in California, 30 percent in Oregon, 25 percent in Nevada, and 23 percent in Washington. The prolonged dryness of the last four years has also depleted reservoirs in most western states, especially in California. In May, Gov. Jay Inslee declared a statewide drought emergency for Washington, and in early July Oregon Gov. Kate Brown planned to order all state agencies to review their water usage and implement conservation plans in the face of the state's growing drought. The Governor has declared drought emergencies in 20 of Oregon's 36 counties so far this year.

While soil moisture improved in the Northeast with above-normal rain, soils dried out in parts of the Southeast where June was drier and warmer than normal. According to June 28th USDA reports, 52 percent of the topsoil was rated short or very short of moisture in South Carolina, 46 percent in Georgia, 35 percent in North Carolina and Mississippi, and 33 percent in Alabama; pasture and range land condition was rated poor to very poor for 34 percent of pasture and range land in North Carolina, 12 percent in South Carolina, and 11 percent in Georgia.

Conditions in the Plains have improved considerably compared to a few months ago. This has contributed to improved national statistics. On a national scale, according to June 28th USDA reports, 13 percent of the topsoil was rated short or very short of moisture, and 23 percent of winter wheat, nine percent of soybeans, nine percent of the pasture and rangeland, eight percent of corn, and five percent of spring wheat were rated in poor to very poor condition. As of June 30th, only two percent of U.S. corn and soybean production was within an area experiencing drought, 14 percent of hay acreage, 15 percent of cattle inventory, and 13 percent of winter wheat production.



Regional Discussion


Hawaii: Hawaii had a mixed precipitation pattern for June 2015 and for much of the last three years (last 2, 3, 6, 9, 12, 24, and 36 months). But in general, below-normal precipitation has occurred over Oahu and most of The Big Island, while the rainfall pattern has been more mixed over the other islands, especially at the longer time scales. On the USDM map, moderate drought increased to about a fourth (24.2 percent) of the state compared to last month (20.1 percent), and severe drought was introduced in parts of Maui and Kauai to reflect agricultural impacts.

Alaska statewide precipitation, May-June, 1925-2015
Alaska statewide precipitation, May-June, 1925-2015.

Alaska: June was generally drier than normal in the western and central portions of Alaska, and wetter than normal in the south central and southeastern coasts, both at the low elevation stations, the high elevation (SNOTEL) stations, and at the climate division level. The West Coast climate division had the driest June on record. The last two months were drier than normal for most stations across the state, especially the central interior and southeastern panhandle stations. Statewide, May-June 2015 ranked as the 12th driest May-June in the state's 1925-2015 record. The interior stations were drier than normal at the three-month time scale. For the year-to-date, drier-than-normal conditions stretched from the interior stations to the west coast, and this pattern is evident at longer time scales (last 9 to 12 months). The precipitation anomaly pattern is more mixed at the 2- to 3-year time scales. The persistent upper-level circulation pattern (ridge), which is responsible for the drier-than-normal conditions, also brought widespread and persistent above-normal temperatures for much of the last year (last 1, 2, 3, 6, 9, and 12 months). Some climate divisions in the north and southeast had record warm temperatures for April-June and January-June, and some in the west and south were record warm for the last 12 months. Statewide, Alaska had the sixth warmest June and second warmest May-June, January-June, and July-June. With the mountain snowpack essentially gone due to the above-normal temperatures, streamflow was significantly reduced. The below-normal precipitation and above-normal temperatures helped to dry out the soils and vegetation, which set the stage for the development of numerous large wildfires (June 16, 23, 25, 29), especially near the end of the month. Abnormal dryness expanded to cover over a half (57.8 percent) of the state, and moderate drought covered about a tenth (9.6 percent), on the June 30th USDM map.

San Juan, Puerto Rico, precipitation, March-June, 1956-2015
San Juan, Puerto Rico, precipitation, March-June, 1956-2015.

Puerto Rico: June continued a dry trend across eastern and southern Puerto Rico which has dominated much of the last year (last 2, 3, 6, 9 months). Only a few areas, mainly in the west, were wetter than normal. The dryness was reflected in low to record low streamflow in the streams on the eastern half of the island, as well as decreasing groundwater and reservoir levels. According to media reports, fish are dying in reservoirs due to lowering water levels and a lack of oxygen, and water rationing has been expanded across several municipalities near the capital of San Juan. June 2015 was the 14th driest June in the 1956-2015 record in San Juan, May-June and April-June each ranked fourth driest, and March-June 2015 was the third driest such 4-month period on record. On the June 30th USDM map, abnormal dryness covered over half (59.3 percent) of Puerto Rico, with moderate to severe drought expanding to over a third (39.6 percent) of the island, which included 14.7 percent in the severe drought category.


CONUS State Precipitation Ranks:

Current month state precipitation ranks Washington statewide precipitation, June, 1895-2015

Oregon statewise precipitation, June, 1895-2015

The June precipitation anomaly pattern of dryness in the Northwest and parts of the Southeast, and wet conditions in the Midwest to Northeast, was reflected in the state ranks, with five states ranking in the driest third of the historical record. Two states ranked in the top ten driest category, including Washington which had the third driest June in the 1895-2015 record, and Oregon, which ranked ninth driest.

The April-June 2015 pattern was similar, with drier-than-normal conditions in the Northwest and parts of the East Coast, while wetter-than-normal conditions dominated the Southwest, Plains, and Midwest. Six states ranked in the driest third of the historical record, one of which (Washington at fourth driest) had the tenth driest, or drier, April-June.

6-month state precipitation ranks California statewide precipitation, January-June, 1895-2015

For the year-to-date, drier-than-normal weather dominated the West and parts of the Southeast, Northern Plains to western Great Lakes, and New England. Twelve states in the West, Southeast, and New England ranked in the driest third of the historical record for January-June 2015. Two states ranked in the top ten driest category, including California (fifth driest) and Oregon (ninth driest). Eleven of the last 15 January-June periods in California have been drier than the long-term average, with the last three being exceedingly dry.

The July 2014-June 2015 precipitation anomaly pattern consisted of dryness in the extreme West, parts of the Central and Northern Plains to Upper Midwest, and parts of the Southeast to Northeast. But areas of above-normal precipitation occurred across the country on a month-to-month basis, and this variability masked the dry regions such that only six states ranked in the driest third of the historical record. No states ranked in the top ten driest category. California had the 29th driest July-June, but it is the persistent dryness since 1999 that has taken a toll on the state. Ten of the last 15 years (July-June periods) have been much drier than normal in the state.

Western U.S.


Percent Area of the Western U.S. in Moderate to Extreme Drought, January 1996-present, based on the Palmer Drought Index Percent Area of the Western U.S. in Moderate to Exceptional Drought, January 4, 2000-present, based on the U.S. Drought Monitor

Percent area of the Western U.S. in moderate to extreme drought, January 1900 to present, based on the Palmer Drought Index
Percent area of the Western U.S. in moderate to extreme drought, January 1900 to present, based on the Palmer Drought Index.

As noted above, dry weather has dominated the West for much of the last three to four years, resulting in significant hydrological (low lake, reservoir, and stream levels) and agricultural impacts. Recent precipitation has helped alleviate some of the short-term impacts, especially in the Southwest, but long-term drought impacts remain. According to the USDM, 60.4 percent of the West was experiencing moderate to exceptional drought at the end of June, which is an increase of about 3.4 percent compared to the previous month. The Palmer Drought Index percent area statistic for the West was 57.7 percent, an increase of about 12.8 percent compared to the previous month.

Except for an occasional interruption, the dryness has been accompanied by unusually and persistently hotter-than-normal weather. When temperatures are integrated across the West, June 2015 ranked as the warmest June in the 1895-2015 record, January-June 2015 ranked as the warmest such six-month period, and July 2014-June 2015 ranked as the warmest such 12-month period. The second warmest such six- and 12-month periods occurred in 1934. As noted earlier, the combination of unusual warmth and dryness has resulted in record dry SPEI values in parts of the West as well as a record extreme June Climate Extremes Index for the West region.

Western U.S. temperatures, June, 1895-2015 Western U.S. temperatures, July-June, 1895-2015

Agricultural Belts


Primary Corn and Soybean Belt precipitation, June, 1895-2015
Primary Corn and Soybean Belt precipitation, June, 1895-2015.
Primary Corn and Soybean Belt precipitation, March-June, 1895-2015
Primary Corn and Soybean Belt precipitation, March-June, 1895-2015.

March serves as the beginning of the growing season for the Primary Corn and Soybean agricultural belt. The region was generally wetter than normal this month, with June 2015 ranking as the seventh wettest and 45th warmest June in the 1895-2015 record, regionwide. The growing season to date ranked as the 14th wettest and 25th warmest March-June on record, regionwide.

NOAA Regional Climate Centers:


A more detailed drought discussion, provided by the NOAA Regional Climate Centers and others, can be found below.

SoutheastSouthMidwestNortheastHigh Plains
West


As described by the High Plains Regional Climate Center, the strong ridge in the West impacted portions of the Missouri River Basin as areas of Wyoming, Montana, and northwestern Colorado had average temperatures in the 4.0-8.0 degrees F (2.2-4.4 degrees C) above normal range. Elsewhere across the High Plains region, temperatures were generally within 2.0 degrees F (1.1 degrees C) of normal, while larger departures on the warm side occurred in areas of Kansas, Colorado, and Wyoming. Meanwhile, precipitation varied across the region with heavy precipitation falling in areas of southeast Nebraska, the Black Hills of South Dakota, and parts Colorado including the Four Corners area and some locations along the Front Range. Most other areas of the region were near normal, however most of Kansas, northwestern Colorado, and southwestern Wyoming largely missed out on precipitation this month. An interesting impact to temperatures occurred at the end of the month when smoke from fires in Alaska and Canada made its way down through the Plains, extending as far south as northern Oklahoma. The smoke created hazy conditions which reduced incoming solar radiation (important for plant development), suppressed temperatures, and allowed for beautiful sunsets and moonrises.

After a record setting May, heavy rains continued into June, alleviating much of the remaining drought conditions in the High Plains region. Over the past month, the total area in drought (D1-D4) decreased from around 7 percent to a little over 1 percent. The last time the High Plains region had this little drought coverage was back in the summer of 2010 when, for several weeks, the region had an areal drought coverage of only 1-2 percent. Over the past month, all drought was eliminated in Colorado and abnormally dry conditions (D0) were all that remained at the end of June. Additionally, drought conditions improved or were eliminated in eastern South Dakota, northeastern Nebraska, and southwestern Kansas. Only a few areas of moderate drought conditions (D1) remained at the end of the month, including a small area of northwestern Kansas, a sliver of southwestern Wyoming, and spotty areas extending from northeastern Nebraska into southeastern South Dakota. D0 decreased over the past month and is now confined to western portions of Wyoming and Colorado, in addition to some areas of western Kansas, northeastern Nebraska, southeastern South Dakota, and western North Dakota.

As explained by the Southern Regional Climate Center, June precipitation in the Southern region was quite variable and, with the exception of south western Texas, the Southern region experienced a warmer than normal month. Heavy May rainfall values have all but eliminated all drought in the Southern region. Near normal June precipitation has allowed for a continuation of May drought conditions in some areas. As of the June 30, 2015 USDM map, only approximately 0.92 percent of the region is in moderate drought. Most of this drought is concentrated in the easternmost counties of Tennessee.

As summarized by the Midwest Regional Climate Center, the heartland of the Midwest saw prolific amounts of precipitation during June 2015, ranking June 2015 as the Midwest's 6th wettest June on record (1895-2015). Total observed rainfall exceed 10 inches (254 mm) in areas of northeast Missouri, sections of southern Illinois and northeast central Illinois, along with north central Indiana and a small portion of northwest Ohio. The driest states in June were Minnesota, receiving only 86% of its normal precipitation (3.68 inches (93.5 mm); normal of 4.29 inches (109 mm)), followed by Wisconsin which received 103% of its normal precipitation (4.35 inches (110.5 mm);normal of 4.21 inches (106.9 mm)).

Heading into June, Minnesota, much of Wisconsin, Michigan, northern Indiana and Ohio, the eastern half of Kentucky, and portions of the immediate Ohio River Valley in Indiana and Ohio were classified as abnormally dry by the USDM with pockets of moderate drought still present across northern Minnesota, the Minneapolis area, and northeast central Wisconsin. The abundant rainfall across much of the region in June alleviated the drought conditions across much of the Midwest with drought conditions nearly vanishing across the Midwest by June 30th, 2015. Too much rainfall, however, quickly changed what looked to be an ideal growing season into questionable growing season due to flooded fields. According to Ag Answers of Purdue University, estimates from models that use reported yields for the current year and prior years, corn and soybean crop loss reached $475 million dollars for Indiana due to ponding water in fields that starved plants of oxygen, leaching away nitrogen. The spread of disease and stalk and root rot were also of concern. On June 8th, USDA NASS rated the corn crop to be promising only to issue three weeks later that the crop would be around the second worst in 10 years. Ohio, Missouri, and Illinois have also reported crop damage from excess water. With all the rainfall came increased cloudiness as well. It was reported to be the cloudiest June on record at Chicago Midway Airport. The airport averaged only 46% sunshine. This broke the old record of 48% sunshine set in June of 1942.

As noted by the Southeast Regional Climate Center, mean temperatures in June were above average across much of the Southeast region. The greatest departures were found across the Carolinas and southern Virginia, where monthly temperatures were 3 to 5 degrees F (1.7 to 2.8 degrees C) above average. Mean temperatures were also above average in Puerto Rico and the U.S. Virgin Islands. Guayama, PR (1914-2015) observed its warmest mean temperature for June on record. The warmest weather of the month occurred from the 15th through the 18th, as the subtropical Bermuda High expanded westward across the region.

Precipitation was generally below normal across the Southeast region, with pockets of exceptional wetness in portions of North Carolina and Virginia. The driest locations were found across northern Alabama and far southern Florida, where monthly precipitation totals were 3 to 8 inches (76 to 203 mm) below normal, or 50 to as little as 5 percent of normal. Stuart, FL (1935-2015) observed its driest June on record with only 1.83 inches (46 mm) of precipitation. Precipitation was also below normal for much of Puerto Rico and the U.S. Virgin Islands during June. Coloso, PR (1905-2015) observed its driest June on record with only 2.40 inches (61 mm) of precipitation.

Moderate-to-severe drought conditions developed across portions of the Southeast during June. The percentage of the region under drought-free conditions (less than D1) decreased from approximately 96 percent on June 2nd to 85 percent on June 30th. Moderate (D1) drought conditions developed across widespread areas of northern Alabama, central South Carolina, and west-central North Carolina, while severe (D2) drought conditions emerged in pockets of southeastern Georgia and northeastern Florida. In addition, severe drought continued to expand across far southern Florida, covering most of Miami-Dade and Broward Counties by the end of the month. The unusual warmth and extended periods of direct sunlight were detrimental to the watermelon crop in southern Georgia. Farmers were concerned that the nearly ripe watermelons could be susceptible to sun scalding, which reduces their exterior attractiveness and ability to be sold. Heavy irrigation was required to maintain the viability of the citrus crop in central and southern Florida, but the lack of rainfall during June aided in crop planting across the Florida Panhandle.

As explained by the Northeast Regional Climate Center, June temperatures varied across the region. The Northeast went from a very dry May to a very wet June. The Northeast saw 7.29 inches (185.17 mm) of rainfall, which was 173 percent of normal and made it the 3rd wettest June on record. The USDM released on June 4 showed areas of moderate drought in New England, New York, New Jersey, and Pennsylvania (totaling 13 percent of the Northeast). In addition, 38 percent of the region was abnormally dry. Abundant rainfall throughout June helped ease some of the dryness. By the end of June, 10 percent of the Northeast was experiencing moderate drought conditions, while 21 percent of the region was abnormally dry.

As summarized by the Western Regional Climate Center, June was warmer than normal throughout the West, especially along the northern tier of the region where many locations set both daily and monthly high temperature records. Above normal precipitation fell in the Southwest due to tropical storm remnants during the first half of the month and monsoon onset in the latter half. Rains this month helped to ameliorate drought conditions in the Four Corners region and parts of the northern Great Basin.

Drier than normal conditions dominated the northern states. Seattle, Washington reported 0.23 in (6 mm) this month, 15% of normal the 4th driest June since records began in 1945. In central Washington, Yakima received only 0.01 in (0.4 mm), far below the normal of 0.62 in (16 mm) and tied for second driest June since records began in 1946. In eastern Oregon, Burns received no measurable June precipitation for the first time since modern records began in 1973. The dryness exacerbated drought conditions in Northwest, favoring expansion and intensification of drought classifications over a large area of western Montana and northern Idaho as well as coastal Washington and Oregon.

Temperatures were near normal in Interior Alaska with some stations along the North Slope and southern coast observing above normal temperatures. Homer, on the Kenai Peninsula, observed its warmest June in an 84-year record averaging 57.8 F (14.3 C) for the month. Precipitation varied across the state, though large areas in the central region are experiencing abnormally dry conditions and in some areas, signs of moderate drought are apparent. Hawaii saw areas of expanding drought conditions on the four major islands this month as well. Precipitation was near to well below normal throughout the state.

Wildfires developed in California and Alaska. In California, lightning ignited the Washington Fire near Markleeville on June 19. It grew to nearly 18,000 acres (7,300 hectares) by the month's end. No structures were damaged, but smoke from the fire reduced air quality in western Nevada. The Lake Fire near Big Bear Lake has charred 31,000 acres (12,500 hectares) since it began on June 17 and has closed or reduced air quality in several popular recreation spots in the area. The cause of the Lake Fire is under investigation. Warm and dry conditions in May and again in the latter half of June favored the development of large wildfires in Alaska. Over 400 fires charred 1.8 million acres (728,000 hectares) this month, breaking the previous record of 1.1 million acres (445,000 hectares) burned by 216 fires.

Pacific Islands: According to reports from National Weather Service offices, the Pacific ENSO Applications Climate Center (PEAC), and partners, conditions varied across the Pacific Islands.

In the U.S. Affiliated Pacific Islands (maps — Micronesia, Marshall Islands, basinwide), June 2015 was drier than normal at Guam, Majuro, and Yap, and wetter than normal at the rest of the stations.

Rainfall amounts were below the minimum thresholds (4 or 8 inches) required to meet most monthly water needs at stations in the Marshall Islands and one in eastern Micronesia. These included Utirik, Wotje, Majuro, Mili, and Pingelap. Utirik received only 2.07 inches of rain in June. Eight of the last nine months (since October) have been drier than 8 inches at Utirik and Wotje. The 4- and 8-inch thresholds are important because, if monthly precipitation falls below the threshold, then drought becomes a concern. Koror was above the 8-inch threshold in June, which breaks a run of five consecutive months when it was below the 8-inch threshold. With over 18 inches of rain, the National Weather Service canceled the Drought Information Statement that was in effect for the Republic of Palau. But with the ongoing El Niño, dry weather is expected to return.

As measured by percent of normal precipitation, Chuuk, Kapingamarangi, Kwajalein, Pago Pago, Pohnpei, and Saipan were wetter than normal in both the short term (June and the last 3 months [April-June 2015]), the year to date [January-June 2015]), and the long term (12-month time scale, July 2014-June 2015). Guam, Majuro, and Yap were drier than normal for June but wetter than normal at the other time scales. Koror was wetter than normal in June but drier than normal at the other time scales. Kosrae was near to wetter than normal in the short term but drier than normal at the longer time scales. Lukonor was wetter than normal for June and the year to date, but drier than normal at the 3- and 12-month time scales.


Pacific Island Percent of 1981-2010 Normal Median Precipitation
Station Name Jul
2014
Aug
2014
Sep
2014
Oct
2014
Nov
2014
Dec
2014
Jan
2015
Feb
2015
Mar
2015
Apr
2015
May
2015
Jun
2015
Jul-
Jun
Chuuk125%121%166%120%66%57%142%134%209%104%89%172%118%
Guam NAS290%62%108%164%75%76%213%6%198%263%291%86%116%
Kapingamarangi86%96%109%130%140%116%229%131%62%87%173%161%110%
Koror121%77%137%63%54%118%64%83%69%74%33%107%80%
Kosrae175%59%77%114%68%86%116%114%91%92%84%143%85%
Kwajalein120%58%88%154%96%68%74%149%994%322%204%117%141%
Lukonor78%77%146%138%70%86%228%97%99%83%89%136%94%
Majuro201%82%134%88%66%67%106%63%329%162%171%57%118%
Pago Pago333%60%40%29%136%141%201%102%64%153%172%170%115%
Pohnpei108%74%128%100%108%104%78%100%138%119%219%108%116%
Saipan113%71%191%105%265%47%184%14%315%203%341%115%135%
Yap110%65%125%77%84%197%92%89%93%139%235%92%107%
Pacific Island Precipitation (Inches)
Station Name Jul
2014
Aug
2014
Sep
2014
Oct
2014
Nov
2014
Dec
2014
Jan
2015
Feb
2015
Mar
2015
Apr
2015
May
2015
Jun
2015
Jul-
Jun
Chuuk14.92"15.55"19.44"13.78"6.99"6.46"14.32"9.68"17.37"13.03"10.08"20.03"161.65"
Guam NAS29.39"9.08"13.66"18.77"5.51"3.87"8.56"0.18"4.09"6.65"9.91"5.32"114.99"
Kapingamarangi12.16"7.84"10.86"10.64"13.02"11.37"20.91"12.19"7.05"11.82"20.84"22.14"160.84"
Koror22.45"10.40"16.10"7.45"6.12"13.14"6.48"7.07"5.11"5.42"3.96"18.66"122.36"
Kosrae26.06"8.32"11.00"12.51"9.38"13.80"19.28"14.73"14.57"16.12"14.89"20.90"181.56"
Kwajalein11.88"5.61"9.49"17.17"10.80"4.54"2.33"3.94"23.37"16.94"13.69"8.12"127.88"
Lukonor12.50"10.80"14.79"15.57"6.37"9.65"19.16"8.70"9.16"9.36"10.36"15.83"142.25"
Majuro22.49"9.64"14.93"11.14"8.85"7.68"8.24"4.32"21.65"15.23"17.27"6.31"147.75"
Pago Pago18.48"3.22"2.60"2.68"13.76"18.13"26.87"12.22"6.88"14.35"16.59"9.07"144.85"
Pohnpei16.74"10.52"16.06"15.32"15.97"16.67"10.24"9.58"18.14"21.94"43.68"16.03"210.89"
Saipan10.04"9.33"19.31"11.15"14.87"1.80"4.66"0.35"5.95"5.34"8.11"4.15"95.06"
Yap16.62"9.58"16.89"9.34"7.40"16.77"5.86"4.60"4.22"7.80"18.41"11.07"128.56"
Pacific Island 1981-2010 Normal Median Precipitation (Inches)
Station Name Jul
2014
Aug
2014
Sep
2014
Oct
2014
Nov
2014
Dec
2014
Jan
2015
Feb
2015
Mar
2015
Apr
2015
May
2015
Jun
2015
Jul-
Jun
Chuuk11.98"12.86"11.71"11.51"10.61"11.25"10.10"7.25"8.32"12.47"11.30"11.66"136.77"
Guam NAS10.14"14.74"12.66"11.44"7.38"5.11"4.01"3.03"2.07"2.53"3.40"6.18"99.09"
Kapingamarangi14.15"8.13"9.93"8.19"9.27"9.84"9.15"9.27"11.43"13.64"12.08"13.78"145.85"
Koror18.53"13.50"11.77"11.84"11.39"11.16"10.18"8.56"7.44"7.32"11.83"17.48"152.90"
Kosrae14.91"14.22"14.22"10.94"13.83"16.11"16.67"12.93"16.06"17.51"17.75"14.64"213.87"
Kwajalein9.87"9.74"10.74"11.18"11.28"6.66"3.16"2.64"2.35"5.26"6.72"6.93"90.41"
Lukonor15.93"14.04"10.15"11.32"9.08"11.27"8.41"8.93"9.26"11.31"11.69"11.65"151.36"
Majuro11.17"11.69"11.17"12.73"13.44"11.39"7.74"6.88"6.58"9.42"10.11"11.01"125.25"
Pago Pago5.55"5.38"6.53"9.26"10.14"12.84"13.34"12.00"10.68"9.39"9.66"5.33"125.57"
Pohnpei15.43"14.26"12.55"15.27"14.83"16.08"13.18"9.55"13.17"18.41"19.96"14.81"182.36"
Saipan8.91"13.13"10.09"10.62"5.61"3.85"2.53"2.59"1.89"2.63"2.38"3.62"70.25"
Yap15.08"14.82"13.50"12.18"8.83"8.51"6.39"5.19"4.56"5.63"7.85"12.04"120.31"

Precipitation amount for current month for U.S. Affiliated Pacific Island stations

Percent of normal precipitation for current month for U.S. Affiliated Pacific Island stations

Percent of normal precipitation for last 3 months for U.S. Affiliated Pacific Island stations

Percent of normal precipitation for the year to date for U.S. Affiliated Pacific Island stations

Percent of normal precipitation for last 12 months for U.S. Affiliated Pacific Island stations


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State/Regional/National Moisture Status
A detailed review of drought and moisture conditions is available for all contiguous U.S. states, the nine standard regions, and the nation (contiguous U.S.):

States
alabama arizona arkansas california colorado connecticut
delaware florida georgia idaho illinois indiana
iowa kansas kentucky louisiana maine maryland
massachusetts michigan minnesota mississippi missouri montana
nebraska nevada new hampshire new jersey new mexico new york
north carolina north dakota ohio oklahoma oregon pennsylvania
rhode island south carolina south dakota tennessee texas utah
vermont virginia washington west virginia wisconsin wyoming

Regional
northeast u. s. east north central u. s. central u. s.
southeast u. s. west north central u. s. south u. s.
southwest u. s. northwest u. s. west u. s.

National
Contiguous United States

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Contacts & Questions
For additional, or more localized, drought information, please visit:

Citing This Report

NOAA National Centers for Environmental Information, Monthly Drought Report for June 2015, published online July 2015, retrieved on April 25, 2024 from https://www.ncei.noaa.gov/access/monitoring/monthly-report/drought/201506.