Drought Monitor drought map valid July 3, Like the last several months, the upper-level circulation pattern was quite active during June with ridge and trough patterns migrating through the jet stream flow over the CONUS.
Drought Monitor drought map valid August 28, Like the last several months, the upper-level circulation pattern was quite active during August with ridge and trough patterns migrating through the jet stream flow over the CONUS.
But this month, troughs favored the central CONUS, which split the ridge on the monthly circulation map. Cold fronts and surface lows moved into the trough bringing near- to below-normal temperatures to a region stretching from the northern Plains to Southeastand this parted the "sea of heat" to the Southwest and Northeast.
The frontal systems also brought above-normal precipitation to parts of the central and southern Plains, eastward to the Mid-Atlantic and Northeast coast.
Monsoon showers peppered parts of the Southwestbut the dominance of upper-level ridging kept most of the West drier than normal.
As a result, drought and abnormal dryness expanded, intensified, or developed in the Pacific Northwest to central Rockies and parts of the northern and southern Plains, Mid-Mississippi Valley, Great Lakes, Hawaii, and Puerto Rico, but contracted in parts of the Southwest, southern to central Plains, and Northeast, and other parts of the Great Lakes, Mid-Mississippi Valley, and Hawaii.
The dry conditions during August were a continuation of persistent dryness for much of the West that has lasted 12 months, and for parts of the Southwest for the last 24 months Standardized Precipitation Index maps for the last 123691224 months.
Drought expansion outweighed contraction this month, but just barely, so the USDM-based national moderate-to-exceptional drought footprint across the CONUS expanded from According to the Palmer Drought Indexwhich goes back to the beginning of the 20th century, about Drought conditions at the end of the month, as depicted on the August 28th, USDM map, included the following core drought and abnormally dry areas: Severe D2 and extreme D3 drought were expanding in the Pacific Northwest, a large area of severe to exceptional D4 drought covered the Southwest, and areas of severe to extreme drought peppered the southern Plains.
The percent area of the West from the Rockies to the West Coast in moderate to extreme drought based on the Palmer Drought Index rapidly increased in December and continued to increase in January and Februarygrowing from Above-normal precipitation improved conditions in California and Nevada in March, so the Palmer percent area in drought shrank to April was wet in northern California and northwest Nevada, and Washington to the northern Rockies, and May was wet in Nevada to southern California, but extremely dry conditions occurred along the coast in May, especially in Oregon and Washington; California to Colorado were dry in June ; the Pacific Northwest to northern and central Rockies were dry in July ; and several parts of the West were dry in August.
The dry conditions were coupled with unusual warmth in parts to much of the West during MayJuneJulyand August which increased evapotranspirationthus exacerbating drought conditions. As a result, the Palmer Drought Index measure of drought area expanded to A large area of moderate to exceptional drought covered the central Plains to Mid-Mississippi Valley.
Pockets of moderate to severe drought were found in the Great Lakes region. Areas of abnormal dryness and moderate drought persisted in the Northeast.
Abnormal dryness and moderate drought persisted in Alaskamoderate drought expanded and severe drought developed in Hawaiiand abnormal dryness expanded in Puerto Rico. Palmer Drought Index The Palmer drought indices measure the balance between moisture demand evapotranspiration driven by temperature and moisture supply precipitation.
The PDSI map shows less severe and extensive drought as well as wet spell conditions in some parts of the country than the PHDI map because the meteorological conditions that produce drought and wet spell conditions are not as long-lasting as the hydrological impacts.
Used together, the Palmer Z Index and PHDI maps show that short-term dry conditions continued in August across much of the West, and a few places in the Plains and Southeast, over areas that were in drought at the end of Julyexpanding and intensifying long-term drought.
Short-term dry conditions occurred in northern parts of the Northeast over areas that were not in drought or wet spell conditions according to the PHDI. Short-term wet conditions occurred over parts of the southern Plains to Mid-Mississippi Valley, reducing the intensity of previous long-term dry conditions.
Short-term wet conditions occurred in parts of the central to northern Plains, Midwest, and Mid-Atlantic to Northeast, expanding and intensifying previous long-term wet conditions.
The SPI maps here show the spatial extent of anomalously wet and dry areas at time scales ranging from 1 month to 24 months.
The SPI maps illustrate how moisture conditions have varied considerably through time and space over the last two years. Dryness in parts of the Southwest can be seen at all time scales.
Much of the West is dry at all time scales except 6 and 24 months. Parts of the extreme northern Plains and Upper Mississippi Valley are dry at all time scales except 3 months.
|Current Conditions | ashio-midori.com||Widespread amounts of inches, with locally inches, were common in the southern and central Great Plains, along the Gulf Coast Gordonin the lower and middle Mississippi, Tennessee, and Ohio Valleys, western Great Lakes region, and the mid-Atlantic. Similar to last week, additional improvements were made in the Midwest, but this week, major modifications improvements were also done in the southern Plains especially Texas and lower Mississippi Valley.|
Dryness in the central Plains to Mid-Mississippi Valley is evident at 6 to 24 months. The southern Plains to Lower Mississippi Valley are dry at 3 to 12 months.
A small part of the Carolinas is persistently dry at all time scales except 6 months. Northern New York and part of the Great Lakes have dryness at the 1- to 6-month time scales. Standardized Precipitation Evapotranspiration Index The SPI measures water supply precipitationwhile 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.
Temperatures during August were above normal across most of the West, especially the Southwest, with record warmth occurring in some areas.Drought Update It was a case of gain and loss this week in Texas.
Numerous areas saw notable improvement of drought conditions while . The U.S. Drought Monitor is produced through a partnership between the National Drought Mitigation Center at the University of Nebraska-Lincoln, the United States Department of Agriculture, and the National Oceanic and Atmospheric Administration.
Rivers are drying up, popular mountain recreation spots are closing and water restrictions are in full swing as a persistent drought intensifies its grip on pockets of the American Southwest. The PDSI map shows less severe and extensive drought (as well as wet spell conditions) in some parts of the country than the PHDI map because the meteorological conditions that produce drought and wet spell conditions are .
an analysis of drought conditions in some american states The data cutoff for Drought Monitor maps is each Tuesday at 8 a.m. annectent Hunt deviates an analysis of the play the odd couple by neil simmon from the possibility that the halogenation falls inconsequentially.
Portions of seven states are already at the highest level of drought on the scale that scientists use, and summer won’t even start for about another two months. If we don’t start seeing some significant rainfall, it won’t be too long before massive dust storms start devastating the entire region.