|Dew Point:||14.8°F (-9.6°C)|
|Wind:||From the ESE at 2.0 MPH Gusting to 9.0 MPH|
|Sea Level Pressure:||29.89" (1012.1 mb)|
... Except for a passing snow shower north of Pittsburgh tonight, cold and dry weather looks to continue through Wednesday. The chance for snow will be more widespread Wednesday night.
NEAR TERM /THROUGH WEDNESDAY/... Latest satellite imagery shows cloud cover invading back in from the north as a shortwave crosses the region. The potential for any light snow tonight will be restricted largely to north and east of Pittsburgh as northwesterly flow on the backside of the trough sets up...but the potential for snow will be brief as inversions quickly lower under increasing subsidence. Accumulations will be minimal with limited moisture restricted to 800mb or lower. Only concern would be the slight possibility for a supercooled rain process scenario due to lack of ice in clouds...but at this time satellite imagery indicates cloud tops around -13C to -14C which is just cold enough...and moisture should be decreasing as tops become slightly warmer overnight.
Cloud cover and the lack of a nocturnal inversion will keep temperatures from falling much overnight with forecast lows only a couple degrees cooler than current observations this evening.
SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... The next low pressure system will weaken as it moves to the north of the area Wednesday night. However, models are keeping the storm system together a bit longer before it weakens compared to 24 hours ago. Slightly expanded the areal coverage of likely pops down to US 422, and now have at least slight chance pops in all locations. Wouldn't be surprised if one or two locations come in with snowfalls over an inch, but this system won't bring anything near advisory level snow.
Snow will move east of the region by Thursday afternoon, but it will be less than 24 hours before more precipitation arrives, this time from the southwest. Didn't make too much change to the inherited pops, but have stuck with the faster solution shown by the SREF/GEFS compared to deterministic models. Many locations could begin initially with some snowflakes, but the bulk of precipitation on Friday will fall as rain. Temperatures each night will drop to around freezing, while highs will rise into the 40s and lower 50s on Friday.
LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... There still is not a lot of model agreement for the extended forecast. There is model agreement in precipitation continuing Friday night into Saturday, and that temperatures should remain warm enough that most precipitation would continue to fall as rain. By Saturday night the ECMWF dries out conditions, while the GFS keeps the surface low around for another 24 hours before transitioning into a lake effect/upslope snow pattern. Once again, have stuck close to the superblend for the long term forecast.