National Drought Summary -- September 27, 2011
The discussion in the Looking Ahead section is simply a description of what the official national guidance from the National Weather Service (NWS) National Centers for Environmental Prediction is depicting for current areas of dryness and drought. The NWS forecast products utilized include the HPC 5-day QPF and 5-day Mean Temperature progs, the 6-10 Day Outlooks of Temperature and Precipitation Probability, and the 8-14 Day Outlooks of Temperature and Precipitation Probability, valid as of late Wednesday afternoon of the USDM release week. The NWS forecast web page used for this section is:
http://www.cpc.ncep.noaa.gov/products/forecasts/.A number of rain events moved across the country again this Drought Monitor week. While the West remained mostly dry, areas of the Midwest, Southeast, and Northeast saw areas of much above normal precipitation.
The Southeast: Large areas of rain moved through the Southeast this week with some areas seeing rain almost every day. The most intense precipitation fell from September 22-24 and spread from Alabama and Georgia, across much of the Carolinas and into the Mid-Atlantic. This rain improved areas of Abnormal Dryness (D0) and Moderate Drought (D1) in northern Alabama, as well as widespread improvement in Abnormal Dryness (D0), Moderate Drought (D1), and to a lesser extend Severe Drought (D2) across the Carolinas. Southern Virginia saw an improvement in Moderate Drought (D1). Conditions continued to improve in Kentucky with this week’s rainfall reflected in reductions in Abnormal Dryness (D0) and Moderate Drought (D1).
The Northeast and Mid-Atlantic: Adequate rains fell this week the Mid-Atlantic and Northeast. No changes were made in the drought status in this area.
The South: Oklahoma was the lucky recipient of multiple rain events this week, something that has not happened in quite a while. While these events did lead to minor improvement in Extreme Drought (D3) in eastern Oklahoma, the precipitation deficits remain large and the impacts wide-spread. No improvement was made in the rest of the state. This same series of storms also moved through Arkansas and southern Missouri. While it did improve short and long-term precipitation deficits some, impacts, especially to agriculture, are still extreme. Despite the rain, recent impact information led to the elimination of improvements made last week in this area. Conditions in Kansas degraded slightly in the central part of the state with a slight expansion of Abnormal Dryness (D0), Moderate (D1) and Severe (D2) Drought. In Texas, mounting dryness in the south, around Brownsville and Beaumont, led to slight degradation of drought conditions. In Texas, 96% of the Pasture and Range land is considered to be in Poor or Very Poor condition, an slight change from last week’s 98%. In Oklahoma, the total is 90% (94% last week).
The Plains and Midwest: Conditions in the Northern Plains deteriorated some this week while in the Midwest, conditions improved slightly. Minnesota saw expansion of Abnormal Dryness (D0) in the southern part of the state. Additional beneficial precipitation this week led to wide improvement in Abnormal Dryness (D0), Moderate (D1) and Severe (D2) Drought across Illinois and Indiana.
The West: The West was generally dry this week with the exception of the extreme Northwest and isolated thunderstorm activity across the region. Drought conditions remain unchanged this week.
Hawaii, Alaska and Puerto Rico: Drought conditions remained unchanged in Alaska and Puerto Rico this week. In Hawaii, mounting agricultural impacts led to the introduction of Extreme Drought (D3) in the northwest of the Big Island and the introduction of Moderate Drought (D1) in western Oahu.
Looking Ahead: During the September 28 – October 3, 2011 time period, there is an enhanced probability of precipitation limited to the Northeast, the Northwest, and the extreme Southwest, early in the period. Later, the above-normal probability of precipitation encompasses most of the West and is eliminated in the Northeast. Below normal temperatures are expected in the eastern part of the country early in the period. Later, the chances shift to near-normal. In the West and central part of the country, temperatures are expected to be above normal throughout the period.
For the ensuing 5 days (October 4 – October 8, 2011), the odds favor cooler-than-normal conditions over much of the Southeast and along the West Coast. Warmer-than-normal to normal conditions are expected across the West, through the Plains and into the Mid-Atlantic and Northeast. The odds of above-normal precipitation are limited to the West and primarily in the Northwest. Normal to below-normal precipitation is expected across the Southwest, through the center of the country and along the East Coast. In Alaska, the odds favor above normal precipitation across the southern part of the state. Below–normal temperatures are expected in the same part in the southern part of the state. The northern part of the state is expecting above-normal temperatures.
Author: Michael Brewer, National Climatic Data Center, NOAA
Dryness Categories
D0 ... Abnormally Dry ... used for areas showing dryness but not yet in drought, or for areas recovering from drought.
Drought Intensity Categories
D1 ... Moderate Drought
D2 ... Severe Drought
D3 ... Extreme Drought
D4 ... Exceptional Drought
Drought or Dryness Types
A ... Agricultural
H ... Hydrological
Updated September 28, 2011
EDIT/END
http://droughtmonitor.unl.edu/