#Drought news (Part 2): Last week’s storminess helps the South Platte Basin drought picture (drought free)

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

Summary

During the past 7-days, moderate to heavy rain (generally 0.5-3.0 inches, locally greater) fell across portions of the Southeast, the Gulf Coast, the Great Plains, and the Ohio Valley. These areas of precipitation occurred in proximity to several slow-moving/stationary fronts and mid-level troughs. By far the heaviest precipitation totals were observed near the Gulf Coast, where numerous coastal counties from southeastern Texas to the extreme western Florida Panhandle received 5-10 inches during the past week. Precipitation amounts were generally light (0.5-inch or less) in the interior Pacific Northwest, the Southwest and the northern Plains…

The Plains

In North Dakota, light rain fell during the past 7-days, offsetting further deterioration of conditions. Temperatures also fell significantly (below freezing in some areas), keeping evaporation rates low. In South Dakota, only slight adjustments were made to the drought depiction. In north-central South Dakota, moderate drought (D1) was extended slightly northward into Walworth and Edmunds Counties. In southeastern South Dakota, moderate drought (D1) was expanded slightly southward to include eastern Hutchinson, central Turner, and northern Lincoln Counties. Most other areas of the state received enough rain this past week (a quarter-inch to an inch) to offset additional deterioration of conditions, but not enough to justify improvements. In the southern portion of the Nebraska Panhandle and nearby southeastern Wyoming, abnormal dryness (D0) was eliminated due to a recent storm system that produced about 2 inches of precipitation (liquid equivalent), much of which fell as wet snow. The region is finally beginning to experience spring green-up. The improved conditions also warranted the removal of abnormal dryness (D0) in the northern Laramie Range in southeastern Wyoming. During the past week in the Sand hills region of north-central Nebraska, 2-4 inch rainfall surpluses and good soil moisture infiltration prompted a 1-category improvement to the depiction. In northeastern Nebraska, despite receiving decent moisture over the past 2 weeks, significant deficits still linger at the 30-, 60-, and 90-day time periods. Therefore, the depiction remains unchanged in this area, pending reassessment next week. In Kansas, respectable rains (mostly 0.5-2.0 inches, locally greater) helped to offset any additional degradation. Surface water supplies are still low, and runoff is minimal. No alteration was made to the Kansas drought depiction this week.

The southern Great Plains also experienced a mix of both improvements and degradations. In Oklahoma, 1-category degradations were made in the western Panhandle, as only 1.0-1.5 inches of rain fell during the past 30-days. There were reports of dust storms and dead dryland wheat across much of this area. In west-central Oklahoma, a swath of 4-8 inch rains prompted a 1-category improvement from about Roger Mills County northeastward to Major County. In extreme northeastern and northwestern Roger Mills County, and most of adjacent Ellis County, no good runoff rains were reported, suggesting status quo for those areas. In Texas, widespread 1-category improvements were made to the drought depiction after recent rain fell over many areas that needed it. Stream flows are improving in southern and south-central Texas, and there is continued reservoir improvement in the Dallas area. In the Panhandle region, some of the wheat crop is expected to be salvaged, but it is unlikely the crop will return to normal…

The West

Moderate precipitation (0.5-2.0 inches, liquid equivalent) fell in much of the Upper Colorado River Basin this past week, though not enough to greatly improve snowpack or stream flows. This region will be monitored for possible improvements next week. In parts of northeastern Colorado, where 1-3 inches of rain have fallen so far this April, 1-category upgrades were made. This includes Cheyenne County in extreme eastern Colorado, and near the northern border with Wyoming. In southern New Mexico, moderate drought (D1) was removed from southwestern Chavez and all of Otero Counties due to good moisture conditions. The Pecos River Valley is doing well on the eastern side of the state, with full reservoirs and commencement of irrigation. Conditions are not as promising though for the Rio Grande Valley.

In northeastern California, exceptional drought (D4) was expanded across the northern Sierras this week, while in northern Modoc County, a one-category improvement (from D4 to D3) was rendered to the depiction to more accurately reflect local conditions. In east-central California near Yosemite National Park, the average surface elevation of Mono Lake stood at 6378.9 feet, as of April 15th. This is the lowest surface elevation of the lake since early 1996. The target elevation is 6391 feet. For the past two weeks, extreme to exceptional drought (D3-D4) covered two-thirds of California. In northern Nevada, a one-category degradation was made to northwestern Elko County, while in southwestern Montana, small improvements were made to the drought depiction in Gallatin County.

In Washington state, record/near-record low snowpack supports the expansion of moderate drought (D1) across the northern Cascades, and the introduction of moderate drought in northeastern Washington…

Looking Ahead

For the ensuing 5-day period, April 23-27, northern New England, portions of Georgia and Alabama, and southern Florida are expected to receive 1.0-1.5 inches of precipitation, which would help in the mitigation of existing dryness/drought. Up to about 2 inches of rain is forecast for the easternmost portions of the drought region in both Oklahoma and Texas, during this period. Light precipitation (0.25-inch or less) is anticipated for most of the Dakotas and upper Mississippi Valley, though western South Dakota is expected to receive 1.0-1.5 inches of rain. Between 1.0-1.5 inches of precipitation (liquid equivalent) is predicted for parts of the West.

For the 6-10 day period, April 28-May 2, there are enhanced odds of near- to below-median precipitation across most of the contiguous U.S. Odds favor above-median rainfall from the central and eastern Gulf Coast region northeastward across the Southeast, mid-Atlantic, and southeastern New England.

Leave a Reply