Updated 22 November 2011

early OctoberDeficient rains lead to a water shortage on the South Pacific island of Tuvalu read more October 17thGiant dust storm rolls through Lubbock, Texas read more October 1stHighest October temperature recorded for the United Kingdom read more early OctoberFloods kill 10 people in Algeria read more mid-OctoberTwo storm systems leave dozens dead across Central America. read more OctoberThailand experiences worst flooding since 1942 read more October 1stSuper Typhoon Nalgae strikes the Philippine island of Luzon read more October 12thHurricane Jova makes landfall in western Mexico near Manzanillo read more OctoberLargest algal bloom in a decade forms along the Texas Gulf Coast read more October 24thTwo people are killed amid heavy rainfall and widespread flooding in Dublin, Ireland read more October 25thStorm leaves nine people dead in Italy. read more October 26thFirst major snowfall of the season hits Colorado. read more October 14thCrack discoved in Antarctica's Pine Island Glacier read more

Drought conditions

Months of deficient rainfall associated with the climate phenomenon La Niña, in combination with well-water contamination from development and population growth and unusually high tides that have mixed salt water with ground water, led to a major water crisis on the small South Pacific island nation of Tuvalu during early October. The situation was so extreme that buckets of fresh water were rationed daily to local families. La Niña conditions in the eastern equatorial Pacific Ocean, which returned in September, continued to strengthen in October and were forecast to gradually continue to strengthen through the Northern Hemisphere winter 2011/12, according to NOAA's Climate Prediction Center. Average rainfall in Tuvalu ranges from about 8–16 inches (200–400 mm) per month.

Satellite aniomation of cold front moving across Texas south plains. Dust can be seen in light grey.
Storm System Satellite Imagery
17 October 2011
Image Credit:
National Weather Service

Wind gusts as high as 75 mph (121 km/hr), in combination with ongoing drought conditions, led to the formation of an 8,000-foot (2,400-meter) wall of dust that made its way to Lubbock, Texas on October 17th. Visibility dropped to near zero as the storm passed through. While dust storms occur occasionally in Lubbock, the timing, strength, and size of the storm was unusual, according to the National Weather Service. The high winds were due to a strong cold front moving through the region, while the drought led directly to less vegetation cover on the ground and thus provided a larger potential source of dust than in normal years. The storm damaged trees and buildings and sparked at least three wildfires in the area.

Please visit NCDC's Drought and Wildfire pages for more detailed information.

[ top ]

Extreme Temperatures

On October 1st, the temperature reached 85.8°F (29.9°C) in Gravesend, Kent, setting a new monthly October maximum temperature record for the United Kingdom. The previous high temperature of 84.9°F (29.4°C) was recorded on October 1st, 1985 in March, Cambridgeshire. October 1st, 2011 was also the warmest October day ever recorded in Wales, as the temperature reached 82.3°F (28.2°C), breaking the previous record of 79.5°F (26.4°C), also set on October 1st, 1985.

[ top ]

Heavy rainfall and flooding

In Algeria, days of heavy rainfall culminated in overflowing rivers and floods at the beginning of October that killed 10 people near El-Bayadh, several hundred miles south of the capital city of Algiers. Hundreds of homes were also destroyed. Heavy rain and flooding is common in Algeria during October.

Central American countries impacted by heavy rainfall during 11–20 October
Central American Countries Impact by Storms
11–20 October 2011
Image Credit:

Two separate storm systems—a tropical depression from the Pacific and another system from the Caribbean—wreaked havoc across Central America, dumping nearly five feet (1520 mm) of rain in some areas during October 11th–20th, according to officials. At least 105 deaths were reported across Honduras, Costa Rica, Guatemala, El Salvador, and Nicaragua. About one million people in total were affected by the storms, which led to major flooding and landslides.

Flooding in the historic city of Ayutthaya on 23 October
Floodwaters in Ayutthaya, Thailand
23 October 2011
Image Credit:
NASA Earth Observatory

Storms and heavy monsoon rains from late July to October contributed to the worst flooding in Thailand since 1942, affecting about nine million people. Floodwaters from the north in August slowly made their way south toward the Gulf of Thailand while heavy precipitation continued to fall. Some areas were under six feet (two meters) of water. The ancient capital of Ayutthaya, a Unesco World Heritage Site, was hit hard by the flooding in mid-October as the Chao Phraya River that surrounds the island city overflowed its banks. The death toll rose to at least 373. Twenty-seven of the country's 77 provinces remained inundated near the end of October, with four million acres (1.6 million hectares) submerged in the north, northeast, and center of Thailand. Several large industrial parks near Bangkok were impacted, idling hundreds of factories and hundreds of thousands of workers, and disrupting global shipments ranging from computer hard drives to automobiles. Damage estimates varied in different media reports, but have been as high as $6 billion U.S. dollars. Other countries in South Asia have also been affected by the heavy rainfall. An estimated 240 people were killed in Cambodia and at least 106 perished in Myanmar.

Radar imagery of rainfall across Ireland on 24 October
Ireland Rainfall Radar Imagery
24 October 2011
Image Credit: Met Eirann

Very heavy rain fell across eastern and northern Ireland on October 24th, making this the wettest October day in Dublin, Ireland since records began in 1954. A total of 3.2 inches (82.2 mm) of precipitation was recorded in South West County Dublin, with most of the rainfall (2.59 inches / 65.7 mm) occurring within a four-hour period, which is an estimated 1-in-80 year event. Average monthly rainfall for October is about 65 mm (2.6 inches). The torrential rains led to widespread flooding that killed two residents in the city.

Flooded streets with mud wall in Monterosso, Italy on 26 October
Flooded Steet, Monterosso, Italy
26 October 2011
Image Credit: Getty Images

The same storm system that affected Ireland also severely impacted parts of Italy on October 25th. Reportedly, up to 19.7 inches (500 mm) of rain fell within a 24-hour period in some locations. The popular tourist destinations of the northwestern coastal region of Liguiria and the central region of Tuscany were among the hardest hit. At least nine people were killed and six were missing due to flash flooding and landslides. Several town were isolated for days in the aftermath of the storm as roads and bridges were washed away or filled with debris.

[ top ]

Tropical Cyclones

Nalgae and Nesat storm tracks and estimated rainfall totals for 26 September–2 October
Typhoons Nesat and Nalgae
24 September–2 October 2011
Image Credit:
NASA Earth Observatory

Less than a week after getting hit by Typhoon Nesat, Super Typhoon Nalgae (locally referred to as Quiel) roared ashore in the Philippines on October 1st. Similar to Nesat, the storm crossed the main island of Luzon, making landfall in Isabela province. The storm reached its maximum strength of one-minute sustained 150 mph (241 km/hr) winds—equivalent to a strong category 4 hurricane on the Saffir-Simpson hurricane wind scale. At least three people were killed before the storm weakened and moved out into the South China Sea, heading for the southern Chinese island of Hainan and then to Vietnam. The Philippines experiences about 20 storms a year on average.

Hurricane Jova estimated rainfall totals for 6–13 October
Hurricane Jova
6–13 October 2011
Image Credit:
NASA Earth Observatory

In the eastern Pacific, Hurricane Jova struck Mexico's western coast near Manzanillo on October 12th with category 2 hurricane force winds of more than 100 mph (160 km/hr). Jova weakened into a tropical depression as it moved inland. At least six people were killed. Jova was the 10th named storm and ninth hurricane of the 2011 Eastern Pacific hurricane season.

Please visit NCDC's Hurricanes & Tropical Storms page for more detailed tropical cyclone statistics.

[ top ]

Severe winter weather

Just two days after a record-high daily temperature of 80°F (26.7°C) was set in Denver, Colorado on October 24th, the first major snowstorm of the season pounded the area. Several inches fell across Denver and more than a foot of snow was reported in several locations, including 19.8 inches (50.3 cm) in nearby Boulder. Tens of thousands of residents lost power as tree limbs crashed down on utility lines. Minor injuries, but no fatalities, were reported.

Snowfall in the northeastern U.S. covers a jack-o-lantern on 30 October
Snow-covered Jack-o-lantern
30 October 2011
Image Credit: AP

Mother Nature played a trick on much of the mid-Atlantic and northeastern U.S. states during October 29th–30th as an unseasonably early, record-breaking nor'easter affected residents from West Virginia to Maine, forcing the disruption of Halloween plans in addition to many other major problems. Heavy, wet snow fell on tree limbs with leaves yet to fall off, which caused the limbs to dip or break off and snap power lines, leaving more than three million residents lost power across the area and creating dangerous conditions on the ground. Connecticut's governor said that this was the largest power outage on record for the state with 800,000 residents left in the dark for up to several days. Hundreds of flights were cancelled or delayed for Philadelphia, Boston, Newark, and New York City airports and some commuter train services were suspended. Jaffrey, New Hampshire recorded the highest storm total of 31.4 inches (80 cm) with well over a foot (30 cm) of snow reported in many other locations. In Central Park, New York City, 2.9 inches (7.4 cm) of snow fell on October 29th, the first time more than in an inch (2.5 cm) of snow has been observed here during the month of October since records began in 1869. Across the region, at least 22 deaths were blamed on the storm.

[ top ]

Polar Events and Sea Ice

Crack in Pine Island Glacier as spooted by NASA's Operation IceBridge on 14 October 2011
Pine Island Glacier Crack
14 October 2011
Image Credit: NASA

According to a NASA blog, the agency's Operation IceBridge saw a large crack in Antarctica's Pine Island Glacier as aircraft flew over the region on October 14th. According to NASA, Pine Island is one of the largest and fastest moving glaciers in Antacrtica. Located in West Antarctica, Pine Island Glacier is a gigantic ice stream that discharges about 100 trillion tons of ice into the Amundsen Sea every year. For several years, scientists have known that the glacier is thinning, and the rate of thinning has quadrupled over the last 18 years. According to the IceBridge project manager, the crack, which will eventually lead to calving (breaking off), is part of a natural cycle. The IceBridge team estimated that the area that could calve in the near future covers about 310 square miles (803 square kilometers). Scientists are concerned about the impact this will have on sea level rise.

[ top ]

Ecosystems Impacts

The ongoing drought in Texas, which began about a year ago, has had far-reaching impacts, including to ecosystems in the Gulf of Mexico. The largest algal bloom in more than a decade—called the red tide bloom—formed along the Texas Gulf Coast and affected areas from Galveston to South Padre Island. The bloom, which depletes oxygen in the water, triggered fish kills and warnings about beach conditions, and released aerosols into the air that irritate respiratory systems. Some regions measured more than 100,000 cells per cubic millimeter of water. During years with normal rainfall, freshwater runoff into bays help keep salinity levels low enough stop these tides. The last red tide bloom occurred during 2009.

[ top ]

Citing This Report

NOAA National Centers for Environmental Information, Global Hazards for October 2011, published online November 2011, retrieved on January 28, 2023 from https://www.ncei.noaa.gov/access/monitoring/monthly-report/hazards/201110.