Tools used in the U.S. Seasonal Drought Outlook (SDO) include the Climate Prediction Center (CPC) seasonal precipitation and temperature outlooks for May-June-July (MJJ), monthly precipitation and temperature outlooks for May, 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, MJJ climatology, and initial conditions such as snowpack and soil moisture. The U.S. Drought Monitor, valid on April 18, was used for initial drought conditions. Latest forecasts show there is a 62% chance of El Nino developing during the MJJ season. 

Continued drought (1 to 3 class) improvement was observed across much of California, the Great Basin, northern Rockies and western Montana due to widespread surplus of precipitation over the region during the past 4 weeks. The exceptionally wet 2022-2023 winter, with multiple atmospheric river events, led to the following California reservoirs to reach or exceed their historical average: Shasta, Oroville, New Bullards Bar, Folsom, Camanche, New Melones, Don Pedro, McClure, Pine Flat, Cachuma, Castaic, San Luis, and Sonoma. However, the Trinity reservoir in northern California is at 48 percent of its historical average. Snow water equivalent (SWE) of more than 150 to 400 percent of normal is observed over the Sierra Nevada Mountains, as of April 17. It should be noted that Lakes Mead and Powell remain low. Although monthly and seasonal outlooks favor below-normal precipitation across much of Montana, an increasing wet climatology, favorable time of year for soil moisture recharge and also above-normal snowpack over western Wyoming, drought improvement or removal is likely over Wyoming and eastern Montana. Persistence is expected for the existing drought areas across the rest of the western region due to an increasing dry climatology and lack of wet signals for MJJ outlook. Above-normal snowpack over most of the western region is expected to limit the chances of development. Drought expansion is likely in the anomalous dry areas over parts of the Pacific Northwest with forecast below-normal precipitation for MJJ. 

Forecast confidence for the Western Region is moderate. 
 
With forecast equal chances of precipitation and an increasingly wet climatology during MJJ improvement or removal of drought is forecast across the northern and central Great High Plains. 40 to 60 percent of the annual precipitation typically occurs during MJJ across most of the region and favorable time of year for soil moisture recharge. Persistence is more likely for southeast Colorado and much of Kansas with drought so well entrenched in these areas that improvement will be difficult.The highest confidence for removal exists across the Dakotas, Nebraska, eastern Montana and Wyoming. 

Forecast confidence is high to moderate for the High Plains Region.

Widespread rainfall was observed across the central and eastern portion of the Southern region during the past 30 days and brought drought improvement or removal over the areas, especially parts of southern Texas where 1 to 3-class improvement was observed, while western portion of the region experienced widespread precipitation deficits with some degradation across the areas. Soil moisture is below the 5th percentile across western Oklahoma and central Texas along with the Oklahoma and Texas Panhandles. With forecast equal chances of precipitation and above-normal temperatures favored, persistence is forecast for the existing drought in west-central Texas and Oklahoma. Removal is forecast along parts of the Texas and Louisiana Gulf Coast due to heavy precipitation forecast during the next two weeks, and above-normal precipitation is slightly favored along the Louisiana Coast during MJJ. 

Forecast confidence is moderate for the Southern Region. 

During the past 30 days widespread heavy precipitation was observed across much of the region with above-normal snowpack over most of the northern portion of the region. Right now, only portions of southwestern Minnesota and western Iowa are designated with drought and improvement or removal is forecast with the MJJ outlook calling for equal chances of below, near, or above-normal precipitation. Also, MJJ is a relatively wet time of year for much of the region and favorable time for soil moisture recharge over the western portion of the region. 

Forecast confidence is moderate to high for the Midwest Region. 

The drought coverage and intensity may have peaked across Florida in recent past weeks. The CPC extended range forecasts , monthly and MJJ outloos all call for above-normal precipitation for the region and the increasingly wet climatology with sea breeze convection during June and July favor removal throughout the region by the end of July.  
 
Forecast confidence is moderate for the Southeast Region.

The Northeast became drought-free at the beginning of February. However, much of the region has experienced widespread precipitation deficits during the past 30 days, especially for the coastal region of New England, which brought drought back over the Delmarva and Long Island where streamflow is also very low. Drought removal is expected over the Delmarva and, based on precipitation during the latter half of April and the MJJ outlook favoring above-normal precipitation. Removal is also forecast for the short-term drought of southern New England since the latter half of April is expected to be wet. 
 
Forecast confidence is moderate for the Northeast Region.

Based on near or above-normal snow water equivalent values throughout the river basins of Alaska, the CPC extended range forecasts near to above normal precipitation, both monthly and MJJ outlooks either leans wet or calls for equal chances of below, near, or above-normal precipitation across the region, drought is unlikely to develop by the end of July.

Forecast confidence is high for Alaska.

Hawaii became drought-free during early February, but D1 drought came back early April for Maui. Since the Islands enter their climatological dry season and the CPC MJJ outlook calls for equal chances of below, near, or above-normal precipitation, persistence is favored with potential development over the anomalously dry areas. 

Forecast confidence is high for Hawaii. 

Due to the forecasts favoring equal chances of below, near, or above-normal precipitation across the region, with the region entering its climatological rainy season, improvement is likely for Puerto Rico.

Forecast confidence is moderate for Puerto Rico.


Forecaster: Yun Fan
 
Next Seasonal Drought Outlook issued: May 18, 2023 at 3PM EDT