Wet Wednesday

Well, we've seen a lot of rain the past few days, and we're only going to be seeing more tomorrow.

There was a slight chance for severe thunderstorms on Wednesday, but with weak mid-level lapse rates currently forecasted, the chance for organized severe weather has decreased significantly.  The vertical wind profile is supportive of strong storm development, but the other ingredients just won't be there to ignite the storms.

So, for tomorrow, expect on and off rain throughout the day with a chance of thunder.

Matthew Flournoy

Meteorology Major | The Pennsylvania State University
Schreyer Honor Scholar | Class of 2015

Rainy Gameday

Unfortunately, the chance for rain will extend across the state just in time for game day.  Fortunately, that chance of rain looks to be limited to a few showers associated with a front, meaning that the rain won't last long.  Most unfortunately, though, those showers are expected to roll through the State College area right around 4 in the afternoon.  Perfect.

Well, it could be worse.  It could always be worse… up in ME, conditions are setting up for the possibility of supercells.  Basically, the development of a supercell is much more promising for severe weather (damaging winds, large hail, and the possibility of a tornado) than a few rain showers.  So let's try to look on the bright side and realize that we're just getting a bit wet.

Not to mention we might not even see a shower tomorrow here in State College.  There is a good chance for a bit of rain here, but one can always hope, right?  

So, regardless of whether we get some rain or not, expect clouds to develop in the morning and persist throughout the day with temperatures rising into the upper 60's and possibly hitting 70 right around kickoff.

As always, enjoy the game folks!

Matt

Matthew Flournoy

Meteorology Major | The Pennsylvania State University
Schreyer Honor Scholar | Class of 2015

Tuesday's Aftermath

As forecasted by the Storm Prediction Center, severe weather rumbled across much of the East Coast yesterday.

A front spawned by a canadian low interacted with a plume of moisture associated with a low pressure system swinging up from the south.  These two systems merged and produced isolated, strong storms (in some cases supercellular) ahead of a broken squall line.  The line also produced severe weather in the form of damaging winds.

Overall, there were 155 severe weather reports - 154 of those being damaging wind, and 1 report of a tornado in NC.  In southeast PA, there were 11 reports of severe wind damage.

In retrospect, the storms did not blow up over PA as much as the SPC predicted they would.  Quite simply, this was due to the absence of CAPE, or available potential energy in the atmosphere.  No potential energy = not much storm development.  We did get some decent rain and some winds here in central PA, but that was due to the front moving through, which already had lift associated with it.  Had there been more CAPE, we would have seen more storm development.  The production of CAPE was limited throughout the day by cloud cover, which prevented significant boundary layer warming.

Overall, though, a very active severe weather day across the East Coast, with a total of 155 reports of severe weather.

Matthew Flournoy

Meteorology Major | The Pennsylvania State University
Schreyer Honor Scholar | Class of 2015

Stormy Tuesday

Expect another batch of severe weather on Tuesday as a cold front and surface low move through the region.

The cold front developed from a strong Canadian low and has been rolling eastward for a couple days, producing strong storms in the Great Lakes region along the way.  Meanwhile, the low pressure system developed down near the Gulf and has been swinging northeastward.  The two look to converge right over PA.  The question is… where in PA?

Recent 4KM WSI RPM models (my favorite) show the front and low combining forces over central/eastern PA, looking to be just east of State College.  When the two merge, a squall line will develop (just east of State College) and rumble eastward, picking up in intensity as it heads toward Philly and NYC and dissipating over western New England.

The timing of the merge between these two systems will ultimately determine the location of the development of the squall line.  This is definitely something to watch for.  This squall line will be associated with the most widespread severe weather of the day, with the primary threat being damaging winds.

There is also a slight chance for tornados forming within supercells ahead of the squall line.  Currently, little CAPE is forecasted for the mid-Atlantic region due to weak mid-level lapse rates.  This could change, though, in places where the clouds break tomorrow morning, which would allow for more surface heating.  Dewpoints will be sufficient to support strong updraft development, with forecasted dewpoints currently pushing 70 for tomorrow afternoon.  Given the right combinations (i.e. already present low-level moisture and possible surface heating), tornadic supercells may form in southeastern PA, northeastern MD, northern DE, and western NJ.

So, overall, expect lots of rain and isolated, strong storms developing throughout the day ahead of the cold front in central PA.  Given the timing of the combination of the front and low, we might see the squall line's effects here in Centre County, or the line might develop just east of us.

Either way, expect lots of rain and strong storms tomorrow afternoon and evening.

Stay safe tomorrow, folks!

Matthew Flournoy

Meteorology Major | The Pennsylvania State University
Schreyer Honor Scholar | Class of 2015

Freaky Friday… Not Really

Nearly a week later, we've got another cold front moving through our state. This one won't be nearly as strong as the one last week, though. Currently, it is making its way into western PA and is producing rain showers with some locally heavy downpours.

There are also a couple isolated cells developing ahead of the line. If one pops up, watch for heavier downpours before the rain showers from the front reach you.

The precipitation along this cold front is expected to dissipate as it crosses over PA this evening. While locations in southern PA might not see any rain at all at this point, locations in to the north should still expect some rain from this system.

After this front passes through, expect cooler temperatures and beautiful conditions over the weekend and into Monday, when our next storm system will swing up from the south. Get outside this weekend while it's nice, folks!

Matt