Deep Mid-Week Trough Will Be Progressive

It is now appearing very likely that a major storm will develop and move up the east coast during the Tuesday/Wednesday time period.  If it were 2 months into the future, we'd be talking early season snows here in the Mid-Atlantic.  Seeing that it is only mid October, a rainy, windy, and raw scenario will play out during the mid-week period.  The model shown below is the location of the surface low late Tuesday evening.

As you can see, this particular model keeps the energy from the diving trough to our west separate from the tropical source of energy in the forms of heat and humidity.  Personally, I believe there will be a bit more phasing of the 2 energy packets creating quite a storm off the east coast....but maybe not as quite as nasty as the Canadian has depicted here in its solution for the Wednesday weather. That is a sub 990 mb low off the Carolina coast....prime position for a winter storm.  But what is lacking is the big high to the north.  The Canadian also has 2 centers of low pressure, but the one off the coast looks to be a bomb!  Take a looksie....

So what does all of this mean?  I believe we are looking at yet another 1-2" rain event to be clearing outta here by Thursday.  Here is the GFS' take on the precip for the period ending Thursday afternoon.  You might be saying that there is not that much forecasted rainfall for here in SE PA.  An astute observation would be my reply!  However, I do believe that there will be a bit more phasing of the diving jet and that more precip will fall over our region than the GFS currently believes.  Look at the moisture in FL....that should hook up with the northern energy and create a heavier rainfall than presently being modeled by the GFS.

Here is that energy as seen by the GFS for Tuesday afternoon.  It is my belief that the upper air energy might be a bit more bundled together (I circled the area in blue where the yellow is all spread out and not bundled more tightly), and thus be creating a stronger storm closer to the natural baroclinicity of the land/ocean interface.  Maybe that is me just wish-casting like I am sometimes accused of during the cold season!  Whatever the case may be, we will most certainly experience at the very least a nasty mid-week wx event to some degree.

Once the storm passes, the coldest air of this fall season will be in place for Friday/Saturday time period, so next week's version of Friday Night Lights will be the coldest of this season to date!  Look at the 850 temps for next Friday morning.  That is a major trough for anytime of the year!  We are also looking at our first major widespread frost for Friday morning and Saturday morning as well.  The growing season should officially be ended following the visit of this trough!

In closing, two 35-7 scores for our district's football teams this weekend.  Enough said there!  As for the Nittany Lions, they do seem to like to keep things close....don't ya think?  And for the NFL and the Eagles...I heard this stat driving into school the other day:  since the start of the present NFL playoff format, there have been exactly 100 teams that have had a record of 1-4 after 5 weeks.  And of those 100 teams, ONLY FIVE have ever made the playoffs (5%) with the slow start.  Thus, it doesn't look too good for the Eagles at the 3/4 pole of this horse race we call the NFL regular season.  I just found that rather interesting.  If this keeps up, maybe Andy Reid will be camped out on Wall Street along side some others looking for work?  Just a thought.....

Have a good remainder of the weekend!

Smitty

AA:  Another storm to affect us mid-week followed by good cool-crisp fall hunting wx!  Will Andy Reid be the "fall-guy" as is so often the case with thanks to these spoiled professional players?

Say Farewell to the Beautiful Fall Wx

Just as difficult as it was to say goodbye to the Phillies 2011 season, it will be equally as difficult to say goodbye to this current spell of beautiful fall wx that has been nothing short of idyllic.  With daytime highs near 80 accompanied with low humidity and overnight lows near 50, fall weather just doesn't get much better than what we just experienced.  But all good things must come to an end and this is true of our current splendid wx.  The high thin cirrus of today is a precursor to this event.  The wx will begin to deteriorate late Tuesday and Wednesday will be a rainy and raw day with once again, I fear, some tropical downpours as the system that is about to affect us has its origins in the tropics!  But before we get to Wednesday's map, lets look at how the 500 mb has been anomalously warm in our area as shown by the ensembles.

However, things will change with the upper air pattern and Wednesday will be the transition day as we experience a wet transition from the storm that has been slamming Florida for the last couple of days.  Again, with the origins of this system from the tropical Atlantic, we should expect to see some heavy downpours along with longer periods of a more stratiform type rain.

The SREFs are showing a very high probability of rain for Wednesday.  It's not very often when the ensembles have a 100% POP at 2.5 days out into the future.  Here are both the NAM and the GFS showing their high likelihood for rainfall Wednesday. 

I expect the truth of the heaviest rain be somewhere in between the maps above.  However, look for ~1.5 inches of rainfall to fall over most of PA by Thursday morning, the bulk of it falling during the daylight hours of Wednesday.

Then a shot of rather brisk and downright chilly fall weather will invade for next weekend.  We should experience much atmospheric instability as some sub-freezing air at 1 mile up will invade PA by Saturday.  The blue line is the 0C line at 1 mile up.  Some lake effect rain and snow showers should materialize over the high ground of northern PA.  Take a look....

Here is the cold anomaly as shown by the GFS ensembles for this upcoming weekend!

Then, after a very brief moderation in temps (I'm not calling it a "warm-up"), another more serious shot of even colder weather will take aim at the Mid-Atlantic as shown by the longer range model here for next Thursday.  If this actual run would verify, the plateau of PA would be experiencing a widespread wet snowfall which is not too early for the north country of PA.  It would not be too surprising if a few snowflakes would be observed in the mountains just north of Harrisburg, which is a tad early!

And here are the ensembles' anomalies for 10 days out.  The further out into time, the more towards "normal" the ensembles trend.  Thus, when one sees an output that is a couple standard deviations from "normal" at this time frame, it sends a fairly clear signal that, in this specific case, cold air will be on the move.

So there are the next  couple of weeks in a nutshell.  A fairly quick synopsis of the pattern leading to a demise of our beautiful fall wx.  Not too dissimilar from the demise of the Eagles season as according to the Elias sports record keepers, the Eagles are one of only 2 teams in NFL history to gain over 1,000 yards offensively in back to back games AND LOSE THEM BOTH!!! That is what happens when you turn the ball over FIVE TIMES in the NFL!  There is no way to win these contests by gift wrapping the rock for the opponent; just doesn't happen at this or really any level of football.  Protect the ball and your likelihood to win dramatically increases.  The Eagles are in trouble, no doubt about that forecast!

Enjoy your week!

Smitty

AA:  Nice spell of wx ends with a rainy Wednesday...then more typical fall like weather, albeit colder than normal.  It could be unsettled with some very cold air aloft.  Looks like northern PA might even see a widespread ground whitening snowfall middle of next week after numerous snow flurries this weekend!