"Year Without a Summer" Brings Cool, Wet Conditions
Great Lakes/Ohio Valley/Midwest

The end of the La Nina pattern will threaten to make this area a region "without a summer." Repeated intrusions of cool air from Canada along with showers and thunderstorms will keep temperatures below normal in many areas. Temperatures topping 90 F may be rare.

The severe weather that has plagued the South this spring will shift northward. Frequent bouts of thunderstorms could mean numerous instances of flooding, hail and wind damage, even tornadoes. While we probably had the most extreme tornado activity of 2011 during April and May, the summer still has potential to bring a few moderate outbreaks of tornadoes.

Flooding may be the biggest concern this summer, as already-soggy ground can handle only so much heavy rain.

Wet Spring Gives Way to Nicer Summer Weather

The Northeast has been frequently cloudy and damp this spring, but that is forecast to change this summer. While not as hot as it was last year, it will become warmer and more humid this summer with temperatures close to long-term averages. That means in major cities along the I-95 corridor, temperatures will hit the 90-degree mark or higher for the typical number of times this summer. The summer may end with good beach weather after a dismal start on Memorial Day weekend.

The region will have its share of rainfall, as more showers and thunderstorms will return during midsummer, and humidity levels may run higher than normal.

Pastelok also added there is always the threat of a tropical system sneaking up the coast from the south, as hurricane season will ramp up by the end of June.

Hot and Dry but Wary of Tropical Storms
Southeast/Southern Plains

After the pattern change, the Southeast will remain hot and dry into the early summer with a high fire danger.

As the season progresses, increasing amounts of thunderstorms, and perhaps tropical systems, could bring some relief from the heat and dryness, but would increase the threat of flooding.

"Areas from the Middle Atlantic on south and west will run with temperatures above normal, but not as warm as last year," Pastelok said. "The dryness in the Southeast will continue into the start of summer."

Pastelok said the chance for early season (June) tropical storm development is possible along the entire Southeast U.S. coast. If the systems are weak and non-destructive, tropical moisture could bring some very beneficial rainfall to the area. However, there is always the chance a system could develop into a hurricane.