#Drought news: Drought is intensifying quickly across the S. tier of this region [High Plains] from S. #CO through W. #KS

Click on a thumbnail graphic to view a gallery of drought data from the US Drought Monitor.

Click here to go to the US Drought Monitor website. Here’s an excerpt:

This Week’s Drought Summary

Light precipitation at best covered most of the 48 states, so drought deterioration was more common than improvement this past week. Less than half an inch fell on most areas across the Southeast, Great Lakes Region, central and northern Plains, Mississippi Valley, Texas, and from the Rockies to the Pacific Coast. Widespread light to moderate precipitation covered the Northeast and the central Appalachians, and a fairly broad area centered along the Ohio Valley received from a few tenths to one-half inch. Farther west, there were a few exceptions to the generally dry week. More than 2 inches of rain soaked parts of the south-central Great Plains and adjacent western Mississippi Valley, western Deep South Texas, and central Montana. The broadest area of heavy precipitation covered a solid swath from south-central Kansas through southern Missouri, where totals ranged from 2 to nearly 4 inches. Similar amounts were more scattered in a stripe from southern Oklahoma and northeastern Texas through southern Louisiana, as well as in central Montana. Isolated sites in southwestern Texas were soaked by as much as 6 inches of rain, but closer to 2 inches fell on most locales there. Elsewhere, there were a few areas of moderate to precipitation from the northern High Plains into central Montana, and in orographically-favored parts of the northern Cascades…

High Plains

Drought is intensifying quickly across the southern tier of this region from southern Colorado through western Kansas. Severe D2 drought is now extant throughout this area, and extreme D3 drought envelops much of southern Colorado and adjacent southwestern Kansas. Most of this region has recorded less than an inch of precipitation during the past 3 months, and at best a few tenths of an inch have fallen mid-March. Abnormally warm weather is exacerbating the acute dryness. The past 3 months have averaged 2 to 4 degrees F above normal, and since late April, averages have been 7 to 9 degrees F above normal. Farther north and east, many areas fell into abnormal dryness this past week as precipitation deficits continued to slowly accumulate. Many areas have seen precipitation totals among the driest 5 percent of historical occurrences for the last 30 days, or 90 days, or both. D0 was introduced where the dryness has been most acute for 1 to 3 months, specifically southeastern Nebraska, a swath from southwest to north-central Iowa, part of eastern South Dakota, southeastern Minnesota, and a large area across central and northern Minnesota. Precipitation has been sharply below normal for at least a few weeks, but impacts have been limited so far. Water supplies, agriculture, and soil moisture have been minimally affected, so the assessment is less intense than most precipitation statistics would imply. At some point, conditions could deteriorate rapidly if these trends continue, so this region must be monitored closely as we move into the growing season.

Farther west, northwest South Dakota and surrounds was one of very few areas to improve this past week, along with part of north-central North Dakota. Generally 2 to 4 inches of precipitations moistened up these regions in the last 2 weeks, eliminating D0 in northwestern South Dakota and adjacent areas.

Precipitation has not been as generous across northern Wyoming, with D0 stretching into northeastern parts of the state, and adjacent Montana. Precipitation among the driest 10% on record was observed in the new D0 areas over the last 4 months. On the other end of the state, abnormal dryness was also introduced in southwestern Wyoming adjacent to Utah…

West

Central Montana was another of the few areas that improved this week, with 1.5 to 3.0 inches of precipitation bringing relief from recent dryness. Other parts of the state missed the beneficial moisture, and precipitation totals among the lowest 5 to 20 percent on record since early February in southwest Montana, prompting D0 expansion into the region. Farther south and west, dryness and warmth led to deterioration in much of Nevada, Oregon, small parts of Washington, and the western Idaho Panhandle. Most notably, extreme dryness stretched southward in central Nevada, moderate drought enveloped much of northwestern Nevada and adjacent Oregon, moderate drought covered the central Sierra Nevada, and extreme D3 drought expanded in north-central Oregon with a general 1-category deterioration introduced farther east. There were some spots where drought eased – significantly, D3 was improved to D2 in north-central California – but the dry and warm week led to much larger areas of intensification. Snowmelt continued at a rapid pace as temperatures in many areas across the West averaged 2 to 5 degrees F above normal for the past 3 months, and 5 to 10 degrees F for the past 2 weeks…

South

Similar to conditions in the Southeast, surplus rainfall has prevailed across the interior, but dryness and drought are entrenched along most of the Gulf Coast, and across southern Texas. Less extreme dryness covers part of central Texas, western Oklahoma and adjacent Texas, and the lower Big Bend. D0 prevails across these regions, with only scattered patches of moderate drought. In contrast, extreme D3 drought has developed in a few regions across southern Texas, primarily near the Gulf of Mexico and along the Rio Grande, while severe drought is impacting a large part of southeastern Texas and smaller areas near the Mexican Border. A small area of intense rainfall – up to 5 inches in spots – brought relief to western Deep South Texas, with the wettest areas improving from severe D2 drought to abnormal dryness (D0). Areas of severe to extreme drought recorded less than half of normal rainfall for the past 90 days, with rainfall deficits of 5 to 7 inches observed southeast of Victoria…

Looking Ahead

During May 14-18, 2020 a broad swath of heavy rain is expected from south Texas northeastward across Missouri, the northern Ohio Valley, the Northeast, and lower New England. Forecasts show a broad, unbroken stripe through this region where more than 1.75 inches of precipitation is expected. Within this stripe, some areas are expecting very heavy precipitation. Most notably, central to south Texas is expecting 3 to locally 5 inches of rain. A few smaller patches are expected to get 3 to maybe 4 inches of rain, including northeast Oklahoma and southeast Kansas, part of north-central Illinois, and northwestern Pennsylvania and adjacent Ohio to near Cleveland. Outside this stripe, precipitation will drop off dramatically. From the Carolinas through Alabama and into central Florida, almost no rain is anticipated. Likewise, precipitation should be lacking from the Great Basin and southern California through most of the Four Corners States. Elsewhere, moderate to heavy precipitation is expected in orographically-favored areas near the Sierra Nevada and Cascades, and in south Florida (especially along the southeastern coastline). Light to moderate precipitation, with totals approaching an inch in a few patches, are expected from the upper Mississippi through the north half of the High Plains to the Pacific Northwest. Most of the 48 states will stay warmer than normal at night, save for upper New England. But temperatures should remain unusually low during the day across the Great Lakes into the northern Plains, and from central California through the Pacific Northwest. Other areas should average a few degrees above normal at night, and near normal during the day.

For the ensuing 5 days, drier than normal conditions are favored from roughly from the Mississippi Valley through the Atlantic Seaboard, and to a lesser extent in parts of the central Rockies and surrounds. There are enhanced chances for surplus precipitation across most of Texas into central New Nexico, across the northern tier of states from the Plains westward, and over the Great Basin and nearby California. Meanwhile, in most locales from the Plains (outside south Texas) eastward across the Mississippi Valley to the Appalachians, odds favor above-normal temperatures. Farther west, subnormal temperatures are favored from the western Rockies to the Pacific Coast.

US Drought Monitor one week change map ending May 12, 2020.

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