Friday, May 04, 2012

Midday Sun May Fuel Late Day Thunder

Another damp atmospheric morning with low clouds and fog around -- visibility levels range from a quarter mile in Jersey to over a mile in Pennsylvania thanks to the wondrous influence of the marine layer.  Given that the warm front made more progress into the region yesterday and didn't retreat much last night we should see it push through the region en masse one way or the other -- if the warm front doesn't fully make it through the region a cool front to our west will push everything out tonight.  That said, we should see west and south get into a hazy sky with some occasional sun first...followed by the city and then gradually with the coast getting in on the action around midday or early this afternoon.

There are some thunderstorms out there this morning to our north -- mainly across Central Pennsylvania now but they will pass through the Poconos and North Jersey before sunrise or shortly thereafter.  Another complex is farther west over NW PA and should stay north of us as it moves through.  With the instability in the atmosphere and the hopeful optimism of some sunshine later on today, the potential for some thunderstorm development does exist...and some of those storms may be on the stronger if not severe side.  Storm Prediction Center has us in a slight risk zone.   Thunderstorms will probably develop off to our north and northwest this afternoon and move on through after 4 PM from northwest to southeast.  There is some uncertainty about how much thunderstorm development takes place given the atmosphere instability is sunshine dependent...and well, yesterday didn't pan out too well on the sunshine department.  If we can get into the sun by midday, we have a pretty good shot at seeing some scattered development of thunderstorms in parts of the area...any of which could bring gusty winds and hail.

Temperatures this afternoon are a "treat" to predict again -- the atmospheric warmth (temps at 60 degrees at 5000' up) support a potential high in the upper 80's this afternoon but with low clouds in place to start, that probably does not happen.  I'm going with 83 for the city but this could bust in either direction if clouds burn quick or burn too slow...temperatures will be cooler east of the city than west...and it's possible the near-the-Shore areas (within 10-15 miles of the coast) struggle to get much above 70.