The largest area of drought is across the Southwest U.S. as we enter early warm season in the U.S. Drought is also present, although not as intense, across the west/northwest Great Plains. Interestingly, the most severely dry evaporative drought demand index (EDDI) is not in the primary drought areas, rather the Mid-Atlantic region and Florida.

The convection phase of the Madden Julian oscillation (MJO) centered near and west of the Dateline in April, developed an eastward extension during the past 10 days resting in the eastern tropical North Pacific. The emergence of this feature is the catalyst to the heavy rains centered on Texas and the southern Great Plains in late April. MJO forecasts indicate a stagnant (MJO) pattern for the first 1-2 weeks of May.

Next week, the ECM is forecasting a low-pressure area to cutoff in the East causing a potential excessive rainfall episode in the Mid-Atlantic States. Using Richmond, VA as an example, rainfall could accumulate to 5-6 in. according to ECM while other models (GFS and GFS ENS) are not nearly as wet.

The 12-month U.S. precipitation trend is useful to determine what parts of the U.S. have the worst drought condition and potential for additional rapid decline in soil moisture given presence of a dry and warm climate as summer arrives. Clearly, the worst conditions are in Nevada/Arizona and Maryland/Delaware/New Jersey.