Drought - October 2011
NCEI added Alaska climate divisions to its nClimDiv dataset on Friday, March 6, 2015, coincident with the release of the February 2015 monthly monitoring report. For more information on this data, please visit the Alaska Climate Divisions FAQ.
Contents Of This Report:
National Drought Overview
Detailed Drought Discussion
October 2011 was near-average (33rd warmest and 51st driest, based on data back to 1895) when weather conditions are averaged across the country. But this reflected regional extremes (in both monthly temperature and precipitation, as well as weekly regional patterns of temperature anomalies [weeks 1, 2, 3, 4] and precipitation anomalies [weeks 1, 2, 3, 4]). Parts of the Southern Plains and Southeast drought areas received beneficial rainfall, but it had little effect on deficits that have accumulated over the last 12 months. Drier-than-normal weather during October, combined with dryness during the previous two months, expanded drought in the Upper Midwest and Plains areas along and west of the Mississippi River. Two-thirds of Hawaii was rated in moderate to exceptional drought at the end of October — a jump of 22 percent compared to last month, due to a dry October. Drought coverage increased in the Southeast (42 percent in moderate to exceptional drought at the end of September rising to 45 percent at the end of October), South (76 to 80 percent), Midwest (14 to 24 percent), and High Plains (17 to 23 percent) regions, but remained steady in the West region (Southwest). Nationally, the moderate-to-exceptional drought footprint increased to about 27 percent of the country, but the percentage in the worst category (D4, exceptional drought) dropped to about 7 percent.
By the end of the month, the core drought areas in the U.S. included:
- a large area of moderate (D1) to exceptional (D4) drought across the Southwest, Southern and Central Plains;
- moderate to extreme drought in the Southeast;
- areas of expanding moderate to severe (D2) drought in the Midwest to Northern Plains; and
- much of Hawaii, where moderate to extreme drought persisted.
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.
As seen on the October 2011 Palmer Z Index map, low precipitation led to short-term drought across the Midwest to Upper Mississippi Valley, central Gulf Coast states, and areas along the border with Mexico this month. Evapotranspiration due to above-normal temperatures is a decreasing factor as we transition to the cold season this time of year. Wet conditions are evident on the Z Index map over a large area from the eastern Ohio Valley to the Northeast, southern Florida, and parts of the Rockies into the central High Plains. Compared with the September 2011 PHDI map, the October 2011 PHDI map indicates that drought conditions intensified along the southern Gulf Coast and spread further into the Mid-Mississippi Valley; drought conditions improved in southern Florida; moist conditions decreased in the Pacific Northwest and parts of the Midwest to western Great Lakes and Upper Mississippi Valley; and moist conditions increased from the eastern Ohio Valley to Northeast. The October 2011 PHDI map also reflects the long-term nature of the drought conditions. The Z Index and PHDI maps in combination show that heavy rains brought relief to the southern Florida drought area, near normal October moisture conditions occurred over parts of the southern drought areas, and dry weather further dried out parts of the Midwest to Upper Mississippi Valley, but for the other southern drought areas and Northeast — precipitation fell where it was already wet and it was drier than normal over the existing drought areas.
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.
Dryness is evident across the Central Gulf Coast states during October (1 month map), the Central to Upper Mississippi Valley and adjacent Plains at 1 to 3 months, parts of the Pacific Northwest to Northern Rockies at 2 to 3 months, the Southwest and Southern Plains at 2 to 24 months, and the Southeast at 3 to 24 months. The Southwest to Southern Plains dryness is most severe at 6, 9, and 12 months. Wet conditions caused by several strong low pressure systems can be seen at 1 month; Tropical Storm Lee rains show up in the Northeast at 2 to 3 months; and the flooding spring rains in the Midwest and Northern Plains show up at 6, 9, and 12 months. In addition to the Northern Plains and Midwest to Northeast wetness, the usually wet conditions from last winter across much of the West are evident in the 12- and 24-month time scales, although dry conditions were eroding into the western wet areas. This illustrates the persistence of the dry and wet areas.
Agricultural and Hydrological Indices and Impacts
Drought conditions were reflected in numerous agricultural, hydrological, and other meteorological indicators, both observed and modeled. Across the drought areas of the Southeast, streamflows were low and many groundwater well stations were at or near record low levels for this time of year. Low streamflows also characterized the drought areas of the Southwest and Southern Plains, where soil moisture was depleted, water restrictions were implemented in many communities, and pastures, rangeland, crops, and natural vegetation were ravaged. Vegetation was stressed and soils dry in the Southeast drought areas as well, and into the Mid- to Upper-Mississippi developing drought areas. Parts of the Southwest, Southern Plains, Central Gulf Coast, and Midwest to Upper Mississippi Valley had few, if any, days with rain in October. This summary is based on the following observed and modeled indicators:
- USGS (U.S. Geological Service) observed streamflow;
- NOAA Climate Prediction Center (CPC) modeled runoff anomalies and percentiles;
- VIC (University of Washington Variable Infiltration Capacity macroscale hydrologic model) 1-, 2-, 3-, and 6-month runoff percentiles;
- NLDAS (North American Land Data Assimilation System) modeled streamflow anomalies and percentiles;
- NLDAS model runoff anomalies and percentiles;
- USGS groundwater observations (real-time network, climate response network, total active network);
- USDA (U.S. Department of Agriculture) observed soil moisture conditions, departures and percentiles, and comparison to 5-year average and 10-year average;
- the Palmer Crop Moisture Index (CMI), which showed short-term agricultural drought in the South and along the Mississippi Valley, but decreased in intensity as the season transitioned further into autumn (weeks 1, 2, 3, 4);
- CPC modeled soil moisture anomalies and percentiles for end of October, soil moisture anomaly change;
- CPC's Leaky Bucket model soil moisture percentiles;
- NLDAS modeled soil moisture percentiles for the top soil layer and total soil layer;
- VIC modeled soil moisture percentiles, soil moisture percentile change;
- USDA observed pasture and rangeland conditions;
- Vegetation Drought Response Index (VegDRI);
- the NESDIS satellite-based Vegetation Health Index (VHI);
- the USGS agro-hydrologic model (Soil Water Index, Water Requirement Satisfaction Index);
- total precipitation (plotted by the USGS and NOAA National Weather Service [NWS]);
- percent of normal precipitation and precipitation percentiles (NWS, High Plains Regional Climate Center station observations, Leaky Bucket model, CPC);
- USGS number of days with precipitation and maximum number of consecutive dry days;
- temperature departures from normal and percentiles (CPC, Leaky Bucket);
- number of record warm daily low temperatures, record daily high temperatures, record daily low temperatures, and record cool daily high temperatures set in October 2011 (from NCDC's daily records analysis).
October 2011 was another drier-than-normal month for most of the stations in the Hawaiian Islands. The prolonged dryness of the last 2 to 3 months caused the percent of the state in moderate to exceptional drought to jump to 66 percent, with virtually all of the state (99 percent) classified in the D0-D4 categories (abnormally dry to exceptional drought). The dryness at 6 months was not as severe, but significant longer-term deficits (last 12, 24, 36 months) remained, especially for the southern islands. Streamflow was below to much below normal and October SPI values were consistently drier than normal for most locations.
Most stations in central and southern Alaska were drier than normal this month, with October 2011 ranking as the fifth driest October in the 1918-2011 record. Dryness was evident at longer time scales (2, 3, 6, 12, 24, 36 months). The October 31st snow water content was below normal, but this is early in the season and the snow depth amounts this time of year are typically low. Although the last 2 months have been dry, August was much wetter, ranking the last 3 months as the 38th wettest August-October statewide, so there was no drought or abnormal dryness indicated on the November 1st USDM.
Most of Puerto Rico was drier than normal during October. The precipitation pattern at 2 months was mixed, but above-normal rainfall dominated at longer time scales (3 and 6 months, and year to date), and streamflow was near average, so the November 1st USDM map had no drought or abnormally dry areas on the island.
On a statewide basis, October 2011 ranked in the top ten driest Octobers for three states along the Mississippi River (Louisiana, Missouri, and Iowa), and five other states in the Mississippi Valley and Central Gulf Coast ranked in the dry third of the historical record. For the last three months (August-October 2011), prolonged dryness in the Upper Mississippi Valley ranked Iowa and Minnesota fifth driest, while Texas ranked sixth driest and 12 other states (in the Southeast, Great Plains, and Northwest) ranked in the dry third category. The dryness in the Southern Plains and Southeast lowered the ranks at longer time scales, with five states (New Mexico, Texas, Oklahoma, Louisiana, and Georgia) in the top ten driest category, and another eight in the dry third category, for May-October. The same five states (New Mexico, Texas, Oklahoma, Louisiana, and Georgia) were in the top ten driest category for January-October, and these same five plus South Carolina were in the top ten driest category for the last 12 months (November 2010-October 2011). Record dryness occurred for Texas at several time scales and Louisiana for December 2010-October 2011, while New Mexico and Oklahoma ranked second driest for several time scales. Widespread and persistent dryness gave the Rio Grande and Texas Gulf Coast river basins the driest November-October in the 1895-2011 record.
During October, moderate to exceptional drought expanded to 80 percent of the South region, 45 percent of the Southeast region, 24 percent of the Midwest region, 23 percent of the High Plains region, and 66 percent of Hawaii. But beneficial rains during the month shrank the worst drought category (D4, exceptional drought) in the South region from 54 percent last month to 42 percent this month. Exceptional drought shrank from 86 percent to 65 percent for Texas, from 66 percent to 43 percent for Oklahoma, and from 35 percent to 26 percent for New Mexico. It dropped from 11 percent last month to 9 percent this month for the contiguous United States.
On a more localized basis, record dryness has occurred for at least one climate division in the Midwest, Southern Plains, or Southeast at every time scale from September-October 2011 through the 12-month period, November 2010-October 2011. Record warm temperatures have occurred for at least one climate division during every time scale from August-October 2011 back through November 2010-October 2011, especially in the Southern Plains during the spring and summer:
The prolonged and intense drought conditions caused a rapid intensification of the PHDI, with several climate divisions reaching record dry PHDI values during the summer. Beneficial October rains backed off the PHDI values to only near-record intensity for many of these climate divisions, but the Trans Pecos division (Texas division 5) still had a record dry PHDI at the end of October. Two river basins (the Rio Grande and the Texas Gulf Coast Basin) also had record dry PHDI values for October 2011.
This water year (October through the following September) began (October 2011) with a mixed precipitation pattern over the West. Parts of the Southwest, Pacific Northwest, and Intermountain Basin were drier than normal, with other parts (especially the Northern Rockies) wetter than normal. A winter storm early in the month dumped snow over the high elevations of the West, but the rest of the month saw warmer temperatures with more rain than snow, so the West ended the month with a below-normal snowpack. The previous water year (October 2010-September 2011) left the West with moist conditions in the north and dry conditions in the south, as reflected in modeled soil moisture and the PHDI, although conditions were drying out some in recent months (2, 3 months) in the Northwest. An analysis of early data by the USDA indicated that reservoir levels were, on average, below normal in New Mexico but near to above average in most other western states. According to the USDM, 19 percent of the West was experiencing moderate to exceptional drought at the end of October, about the same as September, while the Palmer Drought Index statistic was about 15 percent, a decrease of about 1 percent. When the statistics for the Arizona-New Mexico-Colorado drought area (the Southwest drought area) are aggregated, the percent area in moderate to exceptional (USDM categories) drought has fluctuated between 60 and 70 percent for the last eight months. The percent area in the exceptional and extreme to exceptional categories steadily increased from March to June then leveled off with monsoon showers in July, then decreased slightly in August, holding steady at about 32 percent in extreme to exceptional drought at the end of this month.
A more detailed drought discussion, provided by the NOAA Regional Climate Centers and others, can be found below.
West — Upper Colorado River Basin — Pacific Islands
As noted by the Southeast Regional Climate Center, precipitation was highly variable across the Southeast in October. Monthly totals were at least 150 percent of normal across the Florida Peninsula, with some locations exceeding 300 percent of normal. In contrast, October was unusually dry across most of Puerto Rico and the U.S. Virgin Islands. St. Thomas recorded just 1.95 inches (49.5 mm) of precipitation for the month, which was nearly 3.5 inches (88.9 mm) below average. The driest locations across the Southeast (less than 25 percent of normal) were found across Alabama and northwest Florida. Mean temperatures in October were between 1 and 4 degrees F (0.5 and 2.2 degrees C) below average across most of the Southeast region, except along coastal sections of North Carolina and Virginia. Monthly temperatures were generally above average across Puerto Rico and the U.S. Virgin Islands.
There were relatively few changes to the USDM in October. Extreme drought (D3) conditions continued across much of Georgia, eastern portions of Alabama, the upstate of South Carolina, and the western panhandle of Florida. There was a slight improvement from extreme (D3) to severe drought (D2) across parts of central and southern Georgia, while drought conditions were completely eliminated across most of the Florida Panhandle. Drought conditions expanded across Alabama, where precipitation deficits were the greatest.
As explained by the Southern Regional Climate Center, with the exception of central Texas and eastern Tennessee, the bulk of the Southern region experienced a very dry October. In central Texas, stations averaged between 100 and 250 percent of normal precipitation for the month. It is worth noting that these stations received between 4 to 8 inches (101.60 to 203.20 mm) of precipitation for the month. In eastern Tennessee, stations averaged between 100 to 200 percent of normal precipitation, or approximately 3 to 6 inches (76.20 to 152.4 mm) for the month. In contrast, conditions were extremely dry in Louisiana, Mississippi, eastern Texas, and southern Arkansas. Stations in southern Louisiana and southern Mississippi averaged only between 0 to 25 percent of normal, or approximately 3 to 5 inches (76.20 to 127.00 mm) less than they normally receive for the month. Louisiana averaged only 0.82 inches (20.83 mm) for the month, making it their ninth driest October on record (1895-2011). For Mississippi, it was the seventeenth driest October on record with an average precipitation total of 1.10 inches (27.94 mm). Other state average precipitation totals for the month include: Arkansas with 2.48 inches (62.99 mm) of precipitation, Oklahoma with 2.67 inches (67.82 mm) of precipitation, Tennessee with 2.39 inches (60.71 mm) of precipitation, and Texas with 2.18 inches (55.37 mm) of precipitation. Average temperatures varied spatially in the Southern region. For Mississippi, it was the twelfth coldest October on record (1895-2011), while Louisiana recorded its twentieth coldest October on record (1895-2011). In Tennessee it was the eighteenth coldest October on record (1895-2011).
Drought conditions did not change much from September to October in Mississippi, Tennessee and Arkansas. Conditions did change, however, in Texas, Oklahoma and Louisiana. In Oklahoma, much of the central portion of the state saw a one-category improvement from exceptional drought to extreme drought. This was also the case for central Texas, where rainfall was abundant. In Louisiana, the southeast parishes went from being drought-free to moderate drought. In addition, much of the western part of the state was now experiencing exceptional drought. In total for the Southern region, there was a decrease in exceptional drought from 53.77 percent areal coverage to 41.90 percent areal coverage.
The bulk of weather impacts for the Southern region continued to pertain to the longstanding Texas drought. The effects of the drought and wildfires on Texas agriculture have been devastating. Cotton has been particularly hard hit with a loss of more than half of the 7.1 million acres planted this season. With prices being extremely high, cotton crop losses alone have translated into a $1.8 billion loss to the Texas cotton industry. Precipitation during the second half of October helped to replenish livestock tanks and ponds and helped with the planting of fall crops and winter forages, but much more additional precipitation will be needed to maintain growth. Additionally, Texas corn farmers were expected to harvest only about half of the normal 200 million bushels the state normally produces each year. The devastating wildfire season has been estimated to have caused $200 million in damage to Texas agriculture alone. Overall, the $5.2 billion in estimated 2011 losses to Texas agriculture set in August have only increased since this estimate was put forth (Information provided by the Texas Office of State Climatology).
As summarized by the Midwest Regional Climate Center, October precipitation varied considerably across the Midwest. The western half of the region received below normal precipitation while the eastern half received above normal precipitation. Totals ranged from less than 25% of normal in parts of Missouri and Iowa to more than 200% of normal in parts of Ohio. October temperatures fluctuated throughout the month. Despite starting the month with a couple days of cold temperatures, the first half of the month was above normal on average. The second half of the month was below normal despite having a brief warm spell. On average, the month was near normal for much of Missouri, Illinois, Indiana, and Ohio. Kentucky had below normal temperatures, while Iowa, Minnesota, Wisconsin, and Michigan were slightly above normal for the month.
Drought conditions in October improved in eastern Illinois and western Indiana but further west there was expansion and intensification of drought. The small area of moderate drought at the beginning of the month in northern Iowa and southern Minnesota expanded and intensified to severe drought by the end of the month. By the end of October, roughly 20% of Illinois, 40% of Minnesota, 50% of Missouri, and 70% of Iowa were designated in drought.
As noted by the Northeast Regional Climate Center, after a wet August and September, the Northeast began to dry out when high pressure settled over the region around the 5th of October. A series of rain events occurred, followed by a major snowstorm during the second half of the month. The end result was above normal precipitation in the Northeast for the third month in a row. The region's average of 4.83 inches (122.7 mm) was 126 percent of normal. It was the 20th wettest October since 1895. Delaware was the only state with below normal precipitation, at 85 percent of normal. The Northeast averaged warmer than normal for the 10th consecutive month.
As explained by the High Plains Regional Climate Center, the High Plains region experienced a wide range of weather conditions this October including record warmth, record cold, severe storms, variable precipitation, and snow. Overall, temperature departures generally ranged from near normal in the south up to 8.0 degrees F (4.4 degrees C) above normal in the north. Many locations across North Dakota ranked in the top 10 warmest Octobers on record. Little precipitation fell in the eastern part of the region, along the eastern sides of North Dakota, South Dakota, Nebraska, and Kansas. Some locations in these areas were ranked in the top 10 driest Octobers on record. Although the dryness led to the development of abnormally dry and moderate drought conditions, the dry weather did help harvesting activities progress as many days were suitable for fieldwork. By the end of the month, the harvesting of most row crops was either completed or nearing completion. Extremely dry conditions were present early in the month and numerous fires were reported in Nebraska and South Dakota. These fires destroyed crops, combines, center pivots, and even homes. One fire in Stapleton, Nebraska, which is north of North Platte, burned over 25,000 acres and caused around $4 million in damages. Meanwhile, other areas of the region received over 200 percent of normal precipitation. These areas included central Nebraska, northwestern Kansas, pockets of Colorado, and southeastern and northwestern Wyoming.
As summarized by the Western Regional Climate Center, October saw a startup of the winter storm season and the 2011-2012 water year. The first such storm arrived during the early days of October, followed by another significant event about mid-month, and providing above normal precipitation for much of the West. Temperatures were near normal throughout most of the West, with areas of above normal temperatures throughout Montana, Wyoming, eastern California, Nevada, and southern Arizona. Other parts of the West had near normal precipitation. Western Oregon and southern Arizona and New Mexico were drier than normal at most stations. October 2011 was the 16th driest year on record at Eugene, Oregon airport, with a precipitation total of 1.81 in (46 mm), or 51% of the 3.54 in (90 mm) October average. Tucson, Arizona received 0.06 in (1.5 mm), only 7% of the average 0.87 in (22 mm) for that location, making it the 29th driest October on record at Tucson. The low precipitation in the Southwest allowed drought conditions and extent to persist for Arizona and New Mexico throughout October.
Upper Colorado River Basin: As reported by the Colorado Climate Center, the November 1st NIDIS (National Integrated Drought Information System) assessment for the Upper Colorado River Basin (UCRB) indicated that, in October, precipitation favored the higher elevations of the UCRB. The northern and central mountains of Colorado, the Wasatch mountains in Utah, and the San Juans in southern CO all received between 1 and 4 inches of moisture for the month, with some isolated spots in the San Juans and northeast UT receiving over 4 inches. East of the basin, the Sangre de Cristos had accumulations of around 2 inches and northeast CO also received over an inch for the month. Southeast CO and the Colorado River valley in southeast UT were somewhat drier, receiving less than half an inch in many spots. Water-year-to-date (WYTD) SNOTEL precipitation percentiles were in the near normal range throughout most of the UCRB indicated a good start to the winter snowfall season. In the San Juan basin (around the Four Corners), snowpack was near average for the beginning of the season. After a large event earlier in the month, much of the snowpack melted, but was quickly replenished by another system, keeping snowpack near average, and slightly above last year's early accumulations. As of October 30th, 97% of the USGS streamgages in the UCRB recorded normal (25th - 75th percentile) or above normal 7-day average streamflows, with 4 gages recording below-normal flows. During the last week of October, cooler-than-average temperatures dominated most of the UCRB and eastern CO. With the cooler fall conditions and continuous widespread precipitation throughout the drought-stricken areas of southeast CO, water demands eased. The VIC model showed poor soil moisture conditions where long-term dryness has prevailed for much of the year over southeast CO. Most of the UCRB had near-average soil moisture with the Wasatch range in UT and the mountains near the Colorado Headwaters showing wet soils. Parts of eastern UT and Sweetwater County, WY continued to show drying soils. All of the major reservoirs above Lake Powell in the UCRB ended the month near or above their average October volumes. Flaming Gorge and Lake Granby were well above their averages, at 111% and 112% respectively. Lake Powell ended the month at 89% of average and 71% of capacity, compared to 63% of capacity last year.
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.
As noted by the National Weather Service office in Honolulu, below-normal rainfall over most areas of the state during the month of October resulted in an increase in drought intensity and coverage in all four Hawaii counties. All of this occurred prior to the onset of wet conditions which commenced at the end of October and continued into early November. The most notable change in drought depiction since the end of September occurred on the island of Maui where leeward areas deteriorated to extreme drought, or D3 category conditions on the USDM map, from Kamaole to Kaupo. Severe drought, or D2 category conditions, also increased in coverage and encompassed the lower elevations of west Maui from Maalaea through Lahaina. The western third of Molokai worsened from moderate drought, or D1 category, to severe drought. On the Big Island, extreme drought continued along the lower elevations of the south Kohala district, the leeward north Kohala district and the southern end of the Kau district. Severe drought also continued over most of the north Kona district, the Pohakuloa region of the Hamakua district and the eastern portion of the Kau district. Moderate drought also spread to the windward slopes above 3000 feet. Localized drought conditions developed over the lower elevations of southeast Kauai with a small area of severe drought developing near Kalepa following two months of rainfall at less than 50 percent of normal. Severe drought has affected portions of the state of Hawaii continuously since June 2008.
Some drought impacts in Hawaii include the following:
- On Kauai, ranchers in the Kalepa area of southeast Kauai have had to purchase feed for cattle due to poor pasture conditions.
- On Oahu, the water supply in the Waimanalo reservoir continued to decrease and has dropped over 35 feet since early in the year. The State of Hawaii Department of Agriculture implemented a mandatory 10 percent cutback in irrigation water use on October 17.
- On Molokai, the State of Hawaii Department of Agriculture has kept in place the mandatory 30 percent cutback in irrigation water consumption for the Kualapuu reservoir system.
- On Lanai, pastures and general vegetation conditions were in a degraded state. No additional impact information has been received though rainfall totals have been very low.
- On Maui, pasture and vegetation conditions were very poor over the leeward slopes of Haleakala especially from Kamaole to Kaupo. One rancher reported having less than three weeks of feed left and was supplementing with molasses and alfalfa. Water supply levels for upcountry Maui had been decreasing through October but the late October-early November surge in rainfall has helped increase reservoir supplies. The Maui County Department of Water Supply has maintained their call for a 5 percent reduction in water use. The request for a 10 percent reduction in water use by central and south Maui residents also remained in effect.
- On the Big Island, drought conditions began affecting agriculture even on the normally wetter northeast slopes of the island where a rancher in upper Paauilo reported dry pastures above 3000 feet. Pastures and general vegetation from Kawaihae to north Kona were in very poor condition and brush fires continued to be a significant concern. In September the USDA Farm Service Agency reported that various areas of the island had 30 to 100 percent loss of forage for livestock. Many ranchers have already destocked cattle and water hauling operations have been ongoing for several months. Coupled with higher feed prices, the impact on ranching operations has been significant. In other areas of agriculture, yields for tangerines, oranges, and pummelos were down about an average of 50 percent.
On other Pacific Islands, October rainfall was near to below normal in Micronesia, but near to above normal at most other locations.
|Station Name||Nov 2010||Dec 2010||Jan 2011||Feb 2011||Mar 2011||Apr 2011||May 2011||Jun 2011||Jul 2011||Aug 2011||Sep 2011||Oct 2011||Nov 2010-Oct 2011|
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.):
|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.|
|Contiguous United States|
- Palmer Drought Indices
- Standardized Precipitation Index
- long-term (36 to 60 month) percent of normal precipitation maps
- airport station percent of normal precipitation maps
- statewide precipitation rank maps
- Cooperative station percent of normal precipitation maps
- percent of average maps for the SNOTEL stations in the western mountains provided by the Western Regional Climate Center
- satellite-based observations of vegetative health
- National Weather Service model calculations of soil moisture, runoff, and evaporation
- National Weather Service model calculations of soil moisture using the Leaky Bucket Model
- Midwest Regional Climate Center model calculations of soil moisture
- topsoil moisture conditions observed by the USDA and mapped by the Climate Prediction Center
- pasture and range land conditions observed by the USDA and mapped by the Climate Prediction Center
- streamflow maps maintained by the USGS
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