#Drought news: Above normal temperatures, low humidity, high winds, and below normal precipitation in recent weeks = continued degradation in SE #Colorado and SW #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

Precipitation was hit-or-miss this week for many locations east of the Great Plains. Much of the Midwest, South, and Southeast saw combinations of D0 additions and removals based on 7-day rainfall accumulations. Most areas with D0 removal observed at least 2-3 inches of rainfall. Some short-term dryness crept into southern Georgia (isolated 2-4 inch 30-day deficits) and the Florida Gulf Coast (widespread 2-4 inch deficits over the last 14 days). The Mid-Atlantic coast saw some D0 expansion near the Delmarva Peninsula. Portions of New England saw more than 3 inches of rainfall, drastically reducing 30- and 60-day deficits and warranting some D1 removal. However, USGS 7-day average stream flows remain below normal for much of the Northeast. The High Plains and northern Rockies also received some beneficial rainfall. Many locations in Idaho saw 1-category improvements (D1 to D0 and D0 removal), but much of the northern High Plains Region did not receive enough rainfall for much improvement. Some degradation from D3 to D4 occurred in southeastern Colorado and southwestern Kansas in areas where little or no precipitation fell and temperatures averaged above normal for the week. The wildfire risk remains high for many locations that remain in drought, particularly in the West…

High Plains

Above normal temperatures, low humidity, high winds, and below normal precipitation in recent weeks has led to continued degradation in southeastern Colorado and southwestern Kansas. Although some isolated convection occurred in southeastern Colorado, in areas that did not see precipitation and that continued to see above normal temperatures this week, D4 was introduced, which expanded into southwestern Kansas. However, some D0 and D2 reduction was warranted in western Kansas, as 7-day rainfall accumulations of more than 1.5 inches eliminated 30-day departures for several locations. Some areas of Nebraska saw expansion of existing D0 coverage, where 30-day dryness continues. There are concerns of potential flash drought in eastern Nebraska, where 30-day SPIs of D2 or greater are being reported. The northern High Plains saw enough rainfall this week (1.5-3 inches) to warrant D1 reduction in northwestern South Dakota and southwestern North Dakota. The remainder of the region was generally status quo…

West

The Western Region is mainly status quo, except for the northern Rockies and Pacific Northwest, where an active storm track. Idaho benefitted the most, with several locations seeing 1-category improvements, particularly western Idaho, which received 0.5-1.5 inches of rainfall. Light showers in eastern Washington and northeastern Oregon led to slight reduction of D0 and D1 coverages. Soil moisture is below the 10th percentile in many areas across the Great Basin and northern California. USGS 7-day average stream flows also continue to be below to much below normal this week for much of the Four Corners Region, the Great Basin, and northern California…

South

In the Southern Region, the story remains the short-term (30-60 day) dryness. Western Tennessee has missed out in recent weeks on the heaviest precipitation, warranting some D0 expansion (2-3 inch deficits going back 90 days). Northwestern Arkansas and northeastern Oklahoma saw D0 and D1 expansion, as little to no rain fell and most of these areas have received only 10-25 percent of normal precipitation in the last 30 days. 7 inch rainfall deficits in the last 60 days have been observed near Tulsa and Creek Counties in Oklahoma, warranting the addition of a small area of D2. USGS 7-day stream flows are also below normal (10th-24th percentile) for areas around Tulsa County, OK. In western areas of Texas and Oklahoma, heat, low humidity, and lack of rainfall continue to exacerbate existing drought conditions, leading to some D1, D2 and D3 expansion. Widespread D2-D4 SPIs over several time periods for many of these locations…

Looking Ahead

During the next 5 days (July 2-6), WPC’s QPF showed increased probabilities for precipitation across many of the northern tier states, much of the Mississippi Valley, and Southeast, where many areas are favored to receive up to and exceeding 1 inch of precipitation. The Northern High Plains and the Middle Mississippi Valley are expected to see some of the heaviest rainfall (2-4 inches in some cases). Probabilities drop off quite a bit for many locations just east of the Rockies, where below normal precipitation, high winds, low relative humidity, and above normal temperatures continue to be the driving factors for maintenance and exacerbation of drought conditions. Luckily, temperature anomalies are favored to be near to slightly above normal for much of the next week over the western Plains. Much of the Great Lakes is also favored to miss out on some beneficial rainfall in the upcoming week, in addition to positive temperature anomalies of 8-10 °F.

The Climate Prediction Center’s 6-10 day outlook (July 7-11) shows an amplified pattern with a mean ridge over the central CONUS, and troughing over the West Coast and over the eastern CONUS. Enhanced probabilities of below normal temperatures are favored along the West Coast and interior Pacific Northwest, in association with a mean mid-level trough over the West. Above normal temperatures and below normal precipitation are favored in much of the central CONUS, with probabilities for above normal temperatures extending to the Great Lakes and Northeast, underneath a mean ridge. The active storm track is favored to continue for the northern tier states, with elevated odds for above normal precipitation centered over the Upper Midwest and Great Plains.

US Drought Monitor one week change map ending June 30, 2020.

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