Tuesday, February 26, 2013

Updating Tonight's Rain & Pocono Ice

Rain is now moving in from the southwest, occasionally mixed with sleet pellets to our northwest as dry air in the atmosphere is helping cool and freeze some of the rain drops despite surface temperatures that are above freezing.  Temperatures will fall back a bit this evening with precipitation falling in spits and starts over the next couple of hours before the main shield of rain moves through later this evening from the southwest.

For everyone in the immediate Philly metro, this is a predominately rain event. There might be a few sleet pellets in the outer burbs but nothing that will impact your ability to go around town or do anything.  Those sleet pellets may increase in coverage the farther north and northwest you get from Philadelphia.

The Poconos are under a Winter Storm Warning for tonight as the prospect of icy rain and sleet mixing together will create slick driving conditions up there.  Some locations will pick up a pretty decent glaze of icy accumulation, resulting in very slick travel...especially north of I-80 through the night.

Rain will gradually taper off after Midnight from south to north, with northern sections seeing rain end as the morning rush is about to begin (5-7 AM).   The city and south should see rain ending by then although a bit of drizzle could linger into the morning commute.

Rainfall amounts tonight have nudged down a bit on the non-high res guidance -- generally half inch to inch totals are in line. High resolution modeling wants to spit out more than an inch along the coast overnight but the operational NAM, which had been showing similar, has toned back in its most recent run to be more in line with the GFS and Euro with the half inch to one inch across the region.