Tools used in the U.S. Monthly Drought Outlook (MDO) included the Climate Prediction Center (CPC) temperature and precipitation outlooks for July, various short- and medium-range forecasts and models such as the 7-day quantitative precipitation forecast (QPF) totals from the Weather Prediction Center (WPC), the 6-10 day and 8-14 day CPC extended-range forecasts (ERFs), the Week 3-4 outlooks and tools from CPC, dynamical models at the monthly time scale, the 384-hour total precipitation forecasts from several runs of the GFS, and climatology for July. Initial conditions such as current soil moisture and 30 to 90-day precipitation deficits were also factors.
 
Drought coverage and intensity remained nearly steady throughout much of the West during June. 1-category improvements were limited mostly to the Pacific Northwest, while 1 to 2-category degradations occurred across Montana, Arizona, and New Mexico. The persistence of an amplified upper-level trough upstream over the Pacific Northwest is likely to bring above normal precipitation to much of Montana through at least early to mid-July. Therefore, no additional development is forecast during July across Montana and improvement is forecast for parts of the state where the heaviest precipitation is forecast during the next 7 days. A likely delayed start to the Monsoon favors development across Arizona and New Mexico where abnormal dryness (D0) is designated on the U.S Drought Monitor. Elsewhere, throughout the West, persistence is likely due to a relatively dry climatology. 

Forecast confidence is high for the Western Region.

During June, drought coverage expanded and intensified across much of the Northern to Central Great Plains along with Colorado and Wyoming. This increasing drought coverage was due in large part to above normal temperatures this past month. In only three weeks (June 2 to June 23), drought coverage increased from 2 percent to 53 percent throughout Wyoming. Drought is likely to persist across Wyoming and Colorado, while additional development is most likely across parts of southern Nebraska and Kansas. The largest 30-day precipitation deficits (more than 4 inches according to AHPS) across the CONUS exist in southeast Kansas. Little to no rainfall coupled with above normal temperatures are likely to result in rapid drought development across parts of the central Great Plains during the first two week of July. Conversely, prospects for improving conditions are highest across North Dakota due to ongoing heavy rainfall during the final two days of June and the likelihood of a continuation of above normal precipitation during early July. This removal of drought is also consistent with the updated July precipitation outlook. Removal (D1 to D0 in the U.S. Drought Monitor) is forecast for much of western North Dakota, but it should be noted that abnormal dryness (D0) with lingering impacts could still exist at the end of July.

Forecast confidence is high for the High Plains Region. 
 
Rapid drought development and intensification affected the Southern Great Plains since May due to insufficient rainfall, periods of above normal temperatures, and high evapotranspiration rates. According to the U.S. Drought Monitor, drought coverage across Oklahoma increased from 5 percent to 35 percent (May 5 to June 23). Northeast Oklahoma is primed for rapid drought development as this region received less than 1 inch of precipitation during June. Similar to southern Kansas, drought is likely to continue expanding across much of central and northeast Oklahoma during early July due to little or no rainfall and the hottest temperatures so far this summer. Persistence is likely across the ongoing drought areas of Texas with additional development forecast due to increased chances of below normal precipitation and above normal temperatures during July. 

Forecast confidence is high for the Southern Region.
 
Pockets of abnormal dryness have recently developed across parts of the Corn Belt, but heavy rainfall (more than 2 inches) during the final week of June nearly eliminated 30-day precipitation deficits in parts of Illinois and Indiana. Due to the likelihood of much above normal temperatures and little to on rainfall during early July, parts of Indiana and Ohio are the most likely areas to experience drought development. Since the updated monthly outlook for July calls for equal chances of below-, near-, or above-normal precipitation, forecast confidence is lower for development across the Corn Belt compared to the south-central Great Plains. Removal (D1 to D0) is most likely across Minnesota due to predicted 7-day rainfall amounts and enhanced probabilities of above normal precipitation in the updated July outlook.

Forecast confidence is low for the Midwest Region.
 
As of June 23, the Southeast is drought-free for the first time since March 2019. Year-to-date precipitation has averaged more than 150 percent of normal for much of the Southeasst. During the past 30 days, pockets of below normal precipitation (2 inches or less) were observed across parts of the interior Southeast. Based on the updated July outlook, calling for increased chances of above normal precipitation, development is not expected. However, with above normal temperatures favored during July, short-term abnormally dryness (D0) could develop with only a few weeks of insufficient rainfall. 

Forecast confidence is moderate for the Southeast Region.
 
60-day precipitation deficits of more than 4 inches along with periods of abnormal heat during June resulted in drought development across parts of the Northeast. Much of New England is designated with moderate drought (D1) with soil moisture ranking below the 20th percentile and 28-day streamflows in the lowest 10th percentile. Although an upper-level low brought locally heavy rainfall to parts of Maine and New Hampshire at the end of June, persistence is favored on a broad scale given such poor indicators heading into July. Based on the likelihood of above normal temperatures during July and periods of little to no rainfall, additional development is forecast for parts of the Northeast, including the Central Appalahcians. 

Forecast confidence is moderate for the Northeast Region.
 
Alaska has remained drought-free since March. Due to either enhanced probabilities of above normal precipitation or equal chances of below, near, or above normal precipitation forecast during July, development is unlikely by the end of the month. 

Forecast confidence is high for Alaska.
 
Abnormal dryness (D0) and moderate drought (D1) expanded to all of the Hawaiian Islands since May. Due to the lack of a wet signal among the precipitation tools, persistence is favored for ongoing drought areas. 

Forecast confidence is low for Hawaii.
 
According to the U.S. Drought Monitor (valid June 23), nearly 60 percent of Puerto Rico is designated with moderate to severe drought (D1-D2). Given the monthly time scale, persistence is the most likely outcome but heavier rainfall, associated with tropical waves, may off minor improvements. 

Forecast confidence is low for Puerto Rico.
 
Forecaster: Brad Pugh

Next Monthly Outlook issued: July 31, 2020 at 3 PM EDT