A Midweek Morning Shot Of Rain

A storm system working across the South and Ohio Valley will trudge through the Delaware Valley late tomorrow night and Wednesday, spreading rain through the region over about 8-10 hours of time. Computer guidance varies a bit on timing but not too much on details as most of the modeling suggests a rainy start to Wednesday, with the GFS starting rainfall a bit sooner than the NAM and Euro. Regardless of timing, and if we lean on the GFS it looks like a Midnight-Midday event, we should have some rain around town for Wednesday morning's commute.

Rainfall will move in before daybreak, however, and with temperatures likely close to freezing to our north some sleet, perhaps icy rain, could occur on the front end of the precipitation for those north of I-78. It shouldn't be a big deal and as the system lifts through, milder air will work in and precipitation will transition out of frozen or freezing to liquid.   For the rest of us, rainfall will lift through and help usher in a warm two-day stretch that will likely bring us our first 70 degree reading of the year at Philadelphia.   Some locations hit 70 in mid February in the record breaking warm stretch we had a month ago -- in this case 70 does look like it will happen even in the city.

Regarding rainfall amounts, the NAM is the most wet of the three models, painting a stripe of an inch or more across Central into Northeastern Pennsylvania, while giving us a general half inch or so of rain.  The GFS and Euro both paint about a half to one inch for everyone, including those to the north and west.  It won't be enough to increase flooding -- perhaps the NAM will slow the recession of rivers in Central PA if it is right -- but the rain event for midweek will be short duration and out of here in time for Wednesday afternoon's commute.