Monday, February 25, 2013

Rains Still On Tap For Tomorrow Night

We're still on tap for a pretty decent rainfall for most of the region tomorrow night into Wednesday although models vary a bit on amounts.  Outside of that little detail, the main components are still similar -- wind, rain, with icy rain and sleet on the front end in the Poconos before temperatures nudge to 32 degrees up there.  The Poconos and points north could have some ice accrual occur in spots as a cold air wedge sets up shop in this storm up there, keeping temperatures pretty close to freezing in some of the colder valleys that tend to lock in cold more effectively. Freezing rain will not be an issue in Philadelphia with this storm.

The potential for some heavy rain does exist -- the NAM and Euro both suggest an inch to inch and a half are likely south and east of the city with the storm system, with the NAM suggesting isolated amounts higher than two inches in parts of New Jersey before the storm ends.  The bulk of this passes through during the overnight hours.  If the NAM's solution plays out, some localized stream flooding and roadway flooding is possible in the usual suspect locations around the region but this would be not a widespread occurrence.

The GFS is far less robust with rainfall around the region  -- generally a quarter to three quarters of an inch on rain as the bulk of heavier rains pass offshore to our east and southeast as opposed to up the coast.  Rainfall would be light to moderate in nature but much less robust than on the Euro or NAM depiction.

Wind will be an issue, particularly for those south and east of the city, with gusts likely to reach 40 or 45 mph along the coast and sustained winds likely over 20 mph in coastal sections of New Jersey on Tuesday night and early Wednesday. Those gusts will be a bit lower back across Southeastern PA but it will be breezy throughout the region.

So, at minimum, Tuesday night will be rainy.  I tend to lean a bit on the Euro with this event -- which is not as robust as the NAM but generally has the same idea in placing the heaviest rains along and southeast of I-95. An inch of rain for those along and southeast of I-95 seems very reasonable for an expectation at this point.