#Drought news: Some or most of #WY, #Colorado, #NE, and #KS in drought (D1 or drier)

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 and excerpt:

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 2-3 inches of rain, locally to 7 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. For example, Borger, TX, set an all-time record high of 116 degrees F on July 11. 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 (2-5 inches) fell again on non-drought portions of northwestern Puerto Rico and along eastern sections (2-6 inches), slightly trimming away some of the D2 there…

High Plains

Northern and western states had seen an improvement trend the past several weeks as wetter and cooler conditions have gradually eased drought and dryness from Montana and the Dakotas. However, southern states have seen a gradual deterioration this summer, with some or most of Wyoming, Colorado, Nebraska, and Kansas in drought (D1 or drier). Fortunately, several MCCs formed in the north-central and central Plains this week, bringing welcome rainfall (1-3 inches, locally 5 inches) to southern South Dakota, central Nebraska, and central Kansas. As a result, some D0 was removed from northern and eastern Montana, southwestern South Dakota, and parts of central Nebraska and Kansas. D1 was improved to D0 in northern and western North Dakota, southwestern South Dakota, northeastern Nebraska (but expanded into eastern Nebraska and western Iowa), and southeastern Kansas. Lighter amounts (an inch or less) also fell on northern and eastern Montana, most of the Dakotas and Nebraska, northeastern Colorado, and most of Kansas. However, high heat negated the effects of the rain in the southern and central High Plains, causing expansion of D0 and drought (D1-D3) in much of Colorado, southern Wyoming, western Nebraska, and western Kansas. According to USDA/NASS on July 12, topsoil moisture rated short to very short was at 74% (WY), 60% (CO), 47% (NE), 45% (KS), and under 25% in the Dakotas and Montana. Similarly, pasture and range conditions rated poor to very poor was 44% in Colorado, 36% in Wyoming, 22% in Kansas, and 18% in Nebraska. Montana and the Dakotas were also in the teens, but these numbers have fallen (improved) the past few weeks in response to the favorable weather…

West

Dry weather prevailed across much of the West, with the southwest monsoon yet to arrive in the Southwest. While temperatures averaged near or below normal in the northern half of the region, above to much above normal readings baked parts of the Southwest, southern Rockies, and southern High Plains. With the late start to the summer monsoon and oppressive heat, deteriorations were made in New Mexico, Colorado, southern Nevada, southwest Utah, parts of central coastal California, and portions of Oregon. In New Mexico, the combination of extreme heat stress and high ET on what rain that had fallen over the past few weeks included coverage of D0 in southwestern sections, D1 expansion in central and southeastern portions, and some D3 increase in the northwest, northeast, and southeast. Field reports indicated ranchers selling cattle, cutting yearlings off due to no grass, and feeding cake cubes and buying hay. In California, D1 was extended across Santa Clara County and Santa Cruz Mountains due to significant drying of fuels, while southern Nevada went to D1 from D0 due to short-term impacts, lack of WY precipitation, and recent wildfire activity. In Oregon, WYTD SPIs suggested expanding D3 areas as well as field reports for stream flows and soil moisture drying out. In Klamath County, widespread ag, livestock, and surface water impacts necessitated a downgrade to D2…

South

Similar to the Southeast, decent rainfall was generally lacking except for a few areas. Unexpected moderate to heavy (1-3 inches, locally to 6 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, TX, 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 5 days (July 16-20), WPC’s QPF forecasts light to moderate (1 to 3 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.

US Drought Monitor one week change map ending July 14, 2020.

Leave a Reply