The end of spring and beginning to summer is looking warm, according to NOAA’s Climate Prediction Center. Last week, they issued the 90 day outlook covering the months of May, June and July. Warmer than average temperatures are in the forecast for the majority of the nation, from the West through most of the Plains to the Eastern Seaboard. Wetter than normal weather is predicted for the Mid Atlantic into the Ohio Valley, Arizona, and Florida.
With drought conditions ongoing in most of the West and Plains, the 90 day outlook isn’t very promising. Odds favor below average precipitation from the Pacific Northwest to the Plains. This will likely re-enforce the drought and lead to some expansion.
A persistent La Nina was one the driving factors in the forecast and the Climate Prediction Center expects conditions to last for several months. La Nina occurs when the waters of the Pacific Ocean show a general trend of cooling, the opposite of an El Nino. During La Nina periods, the Jet Stream is not usually active in the Southern U.S. This usually leads to less storms systems and below average precipitation. Cooler than normal weather typically occurs across the northern tier of the country and occasionally wetter periods as well.
The latest model guidance, soil moisture/drought conditions, and decadal trends also impacted the May through July outlook.