Tools used in the U.S. Monthly Drought Outlook (MDO) include the Climate Prediction Center (CPC) updated temperature and precipitation outlooks for April, 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, dynamical model output, April climatology, and initial conditions such as soil moisture and snowpack. The U.S. Drought Monitor, valid on March 28, was used for initial drought conditions. 

During the past 4 weeks, several atmospheric river storms moved across much of the West Coast and brought another 10 to 20 inches of rainfall along much of the coastal region and multiple feet of snowpack to some higher elevations. Widespread drought improvement/removal was observed across the region, especially in central and southern California. Continued drought improvement or removal is likely across parts of northern California, Oregan, the Great Basin and Northern Intermountain Region by the end of April, based on beneficial 7 day precipitation forecasts, near to above-normal monthly precipitation outlooks along with expected snowmelt due to existing above normal snowpack over the region. In addition, most of California's reservoir levels have increased steadily since this winter. As of March 31, the following California reservoirs are above their historical average: Shasta, Oroville, New Bullards Bar, Folsom, Comanche, Don Pedro, McClure, Pine Flat, San Luis and Cachuma. However, Trinity reservoir in northern California is at 51 percent of its historical average. It should be noted that it will take more than one wet winter to significantly replenish Lake Mead and Lake Powell which are critical for water supplies across southern California. Due to lack of wet signals in the forecasts, drought persistence is likely over Montana. The southern parts of the region is trending to its dry climatological seasons with the forecast below-normal precipitation in the April outlook,and broad-scale persistence for remaining drought areas is expected over the region. 

Forecast confidence for the Western Region is moderate. 
 
The April outlook depicts equal chances in the precipitation pattern across the northern Great Plains along with above normal snowpack, most areas trending to its climatological wet season and a favorable time of year for soil moisture recharge. Broad -scale improvement/removal of long-term drought is the most likely outcome for portion of this region.   

Forecast confidence is moderate for the High Plains Region.

During the past 4 weeks, heavy precipitation was observed across much of the Ozarks area and brought 1 to 3-category drought improvement over parts of central Oklahoma and adjacent northern Texas. However, 1 to 4 inches rainfall deficit was also observed across the Texas Panhandle and southern part of the region. A 1 to 2-category degradation was made to much of the above areas. Due to lack of wet signals from short range forecast to monthly outlook, coupled with above-normal temperatures, declining soil moisture, and a dry climatology to April, drought persistence is expected for most of western Texas. Conversely, forecast above-normal precipitation through April supports drought improvement or removal for eastern Texas. 

Forecast confidence is moderate for the Southern Region. 

A series of winter storms across much of the Midwest during the past 4 weeks resulted in above-normal precipitation and brought a broad 1-category improvement in Dx categories to the existing drought over the above region. Additional drought improvement or removal is likely for Minnesota and Iowa due to above- normal snowpack and the area trending to its wet climatological seasons. Drought removal  is favored for the remaining drought area in southeastern Michigan as above-normal precipitation is forecast for April. 

Forecast confidence is moderate for the Midwest Region. 

During the past month, abnormal dryness (D0) and short-term moderate drought (D1 to D3) continues to expand across the Florida Peninsula where many areas experienced 1 to 4 inch rainfall deficits. Also, temperatures were unseasonably warm which contributed to worsening soil moisture (below the 20th percentile) and increased wildfire danger. April forecasts call for equal chances for precipitation and above-normal temperatures across much of the region, coupled with a dry climatology for the month and a favorable time of year for soil moisture discharge. Persistence is favored for the existing drought areas with additional drought development in northern Virginia where streamflow was much below-normal. 

Forecast confidence is moderate for the Southeast Region.

The Northeast became drought-free by the beginning of February. However, drought reappeared near Delmarva in late March. Forecasts for April call for equal chances of precipitation and above-normal temperatures across much of the region with low streamflow over the Delmarva. Persistence is likely for the existing drought over the above areas with additional development in nearby abnormal dry (D0) areas. 

Forecast confidence is moderate for the Northeast Region.

Based on near or above-normal snow water equivalent values across most of Alaska, drought is unlikely to develop by the end of April.

Forecast confidence is high for Alaska.

The CPC monthly precipitation outlook for Hawaii depicts a continued wet pattern through April while the Islands are in transition to their climatologically dry season. Hawaii is likely to remain drought-free through the end of April. 

Forecast confidence is moderate for Hawaii. 

Drought persistence over northwestern and extreme southern Puerto Rico is likely since dynamical models depict near to below normal precipitation through April while the area is transitioning to its rainy season. 

Forecast confidence is low for Puerto Rico.


Forecaster: Yun Fan
 
Next Monthly Drought Outlook issued: April 30, 2023 at 3PM EDT