Monday, May 06, 2013

From "Spring" To Summer In The Midwest Next Week

The topsy-turvy last couple of weeks in the Midwest -- 80's one day, snow a few short days later -- may be about to jump into full blown summer next week and if the Euro computer model is correct, Minneapolis could see its first 90 degree day of the summer before we in Philadelphia do.

For some, that's not a bad thing.  For Minneapolis, it might be a bit of a shock to the system given it has only surpassed 80 once so far this spring.

In response to the cold front that crosses through the Northeast this weekend, a couple of cooler days are likely for us in Philadelphia.  In fact, some Pocono frost can't be ruled out on either Monday or Tuesday morning with lows in the 30's possible in spots around the region next week.  The warmup on the backside of the cold surge will allow for warmth to push northeast into the Plains and Upper Midwest for at least a day or two next week.

Looking at the 850 mb (5000') temperature profile, temperatures in the lower atmosphere may reach 20 degrees Celsius in Minneapolis next Tuesday according to the Euro.  This would support a run towards 90 for them in the afternoon, especially since the prevailing wind trajectory is southwest.

Like us, Minneapolis warms the most with a southwest wind since the trajectory brings it from the Plains and from a downslope off of the Rockies.  It's likely the Dakotas end up a bit warmer than Minneapolis -- mid 90's could result in the usual warm spots out in the middle of the Dakotas (Pierre, SD for one).  While this level of warmth in mid May is not entirely unusual, it's still a bit shocking to an area that hasn't had much warmth this spring.

As of us, some of this warmth spills over in the middle and latter portions of next week.  Upper levels don't support it quite getting to 90 here as of now but there's a pretty good chance we get into the 80's next week.  The magnitude of warmth that we could experience would depend on the rainfall that we pick up later this week...if we skate through this week with little in the way of rain, the relatively dry conditions could help coax a few extra degrees out.  It'll be something for warmth watchers to keep an eye on.