Source: https://droughtmonitor.unl.edu/
Map released July 16, 2020 | Data valid July 14, 2020
This week’s drought summary: The active Atlantic hurricane season continued (with respect to number of named storms) as minimal Tropical Storm Fay formed off the Carolina coast, moved northward, and made landfall in New Jersey. Rainfall from Fay was beneficial for parts of the Northeast, especially the Delmarva Peninsula, New Jersey, Eastern Pennsylvania, and Western New York, where two to three inches of rain, locally to seven inches, brought widespread relief from growing short-term dryness and drought. Lighter totals also fell on most of New England, but most areas did not receive enough rain to make any marked improvements. Elsewhere, a series of slow-moving fronts drifted across the lower 48 states, generating MCCs (Mesoscale Convective Complexes) with swaths of decent rain across parts of the central Plains, Midwest, and Southeast. Several fronts produced scattered but heavy thunderstorms across the upper Midwest. Unfortunately, many areas received little or no precipitation this week, including much of the West (from the Rockies to the Pacific Coast), the Southern Plains, lower and middle Mississippi River Valleys, and most of the Appalachians and Piedmont. Unfortunately, the dryness was accompanied by excessive heat (weekly temperatures averaged more than 4 degrees F above normal) in the southwestern and northeastern quarters of the nation. The combination of heat and minimal rainfall was a concern for many agricultural areas as crops are at critical stages of growth and reproduction, and with high evapotranspiration rates during the summer heat, topsoil moisture can become rapidly depleted and stress the crops. In contrast, the Northwest recorded subnormal temperatures (2 to 6 degrees F below normal), along with some light precipitation in northernmost regions. In Alaska, light to moderate precipitation fell on southern, central, and southeastern sections, while Hawaii saw some windward showers early in the period but not enough for any improvement. Heavy rains (two to five inches) fell again on non-drought portions of northwestern Puerto Rico and along eastern sections (two to six inches), slightly trimming away some of the D2 there.
South: Similar to the Southeast, decent rainfall was generally lacking except for a few areas. Unexpected moderate to heavy (one to three inches, locally to six inches) rains from a couple of MCCs fell on the south-central Great Plains (central Kansas and eastern half of Oklahoma), providing some relief from drying conditions. Tulsa, OK, measured only 0.11” of rain in June, but has 4.00” the first 13 days of July. The rains also ended excessive heat over the weekend when Borger, Texas, set its all-time highest reading at 116 degrees F on July 11, and numerous Oklahoma sites exceeded 115 degrees F for their heat index (two sites hit 120 degrees F). Heavy (1.5-5 inches) rains also fell on west-central Tennessee, but mostly missed the three small D0 areas of Western and Central Tennessee. Accordingly, the D0 in Western Tennessee expanded, along with a new D1 area near Memphis, and a new D0 in Northeastern Tennessee. Scattered light amounts (inch or less) were observed in the Texas Panhandle, across Central and East-Central Texas, most of Louisiana and Arkansas, and the southern two-thirds of Mississippi. In contrast, little or no rain combined with excessive heat (weekly temperatures averaging 4-10 degrees F above normal) exacerbated conditions in southwestern Texas, the Texas and Oklahoma Panhandles, and much of New Mexico. According to USDA/NASS for the week ending July 12, topsoil moisture short to very short (in parentheses) gained percent points from the past week in Texas (67%), Louisiana (20%), Arkansas (35%), Tennessee (29%), and Mississippi (14%), but dropped in Oklahoma (45%) as expected with the widespread rains. Not surprising, July 12 crop conditions in Texas rated very poor or poor was: corn (12%); cotton (41%); sorghum (22%); peanuts (17%); oats (22%); and pastures and ranges (39%). South Texas remained wet at 60-days and beyond, but continued lack of rain and heat should soon start taking a toll on the soil moisture and agriculture.
Looking ahead: During the next five days (July 16-20), WPC’s QPF forecasts light to moderate (one to three inches) rains across the middle Mississippi River Valley, upper Midwest, and southern Florida. Lighter totals are expected in the southern Rockies and South-Central High Plains, along the Central Gulf Coast, and in the Appalachians. Little or no rain is anticipated in the West, Southern Plains, portions of the Southeast, and along the Northeast Coast. Most of the lower 48 states should expect above-normal temperatures, with subnormal readings limited to the Northern Plains.
The Climate Prediction Center’s 6-10 day outlook (July 21-25) favors above-normal rainfall across the northeastern quarter of the contiguous U.S., along the Western Gulf Coast, in Arizona and Utah, and in Western Alaska. Odds for subnormal precipitation are likely in the Pacific Northwest, the Central Plains, and along the southern coast of Alaska. A tilt toward above-normal temperature probabilities were found across much of the lower 48 states and along Alaska’s southern coast, but highest odds were found in the Central Plains and northeastern quarter of the nation. Subnormal readings were limited to the northern two-thirds of Alaska.