Wow, tough question. Honestly I really have no idea beyond speculation, I know very little about large scale climatic forecast and trends. The best I can do is provide you with others thoughts, though honestly the're probably not doing much more than speculating either. NOAA issues long term forecast, they forecast Difference from average for temperatures and precipiation. According to them it really appears things SHOULD be normal across this region of the Country maybe slightly warmer, as one works westward, here is their Forecast departure from average for May-July
http://www.cpc.ncep.noaa.gov/product...off03_temp.gif
They seem to think we will be about average for precip too. I do know we are in a La Nina, though if it will remain strong through the summer is still in question. That being said, typically La Nina means the Jet Stream is farther to the NW, hints why they forecast warmer than average for the West, a the jet stream being farther to the NW would lead me to believe that much of the time the jet stream will be near or over this region meaning I would expect rather wide temperature swings, and maybe more active than normal severe weather season. For the latest forecasts check this site...
Climate Prediction Center - Seasonal Color Maps