PHILLY MONDAY WEATHER UPDATE

Last night’s GFS model continued with the scenario that a low pressure system was going to develop off the coast, but miss us.  However, the recent trends have been to place this system closer to the coast with greater intensification.

This morning’s NAM has suddenly jumped on this scenario, with low pressure in a similar position, but somewhat more intensified, allowing some snow to move in on the western side and into the PHL area late Monday into Monday evening.

[su_note note_color=”#ebf2d9″]With the system evolving, the timing and QPF values and timing are likely to change.  Current QPF is a very light 0.16 inches water.  Currently not much of a ‘storm’, but driving could be slippery on Tuesday morning rush hour as cold air will be in place.[/su_note]

As mentioned in last night’s post, the GFS has been hinting at something happening off the coast.  This weak signal has been strengthened; some winter precip is looking more likely for late Monday.

NAM prediction for Monday evening
Saturday Morning NAM prediction for Monday evening

Expect details and timing to change.

PHILLY WEEKEND WEATHER FORECAST

After all the time needed to forecast the past two storms, it’s nice to have a quiet weekend weather-wise.

High pressure builds in for the weekend bringing sunny skies for Saturday and cold temperatures. Still a bit windy. High 46.

The same high pressure will suppress low pressure to our south on Sunday. Sunday will be mostly sunny, but some mid level clouds may move in during the afternoon as a disturbance moves to our south . High 47.

It currently appears that low pressure will remain to our south on Monday, although the GFS is still having difficulty resolving the evolution and path of the low pressure system on Monday.  I’ll keep an eye on it.

[su_note note_color=”#ebf2d9″]Fri 11pm:  Tonight’s GFS is still trying to spin up a deep low pressure system Monday night, that still misses us .  Something is going on. We’ll need to keep an eye on this. [/su_note]

Monday evening GFS