940 FXUS61 KCTP 110440 AFDCTP Area Forecast Discussion National Weather Service State College PA 1140 PM EST Wed Feb 10 2021 .SYNOPSIS... An active winter weather pattern will continue in Central PA through early next week with several opportunities for snow and mixed precipitation. Below normal temperatures are forecast through mid-February. && .NEAR TERM /THROUGH THURSDAY/... Light snow is falling across nearly all of central Pa late this evening in advance of weak shortwave approaching from the midwest. Back edge of the steadiest snow is entering western Pa at 04Z and near term model guidance indicates snow rates will diminish across central Pa between 06Z-08Z, as low level jet and strongest waa shift east. An examination of model time sections indicate the greatest lift occurring just below the DGZ, supportive of snow/water ratios close to 15/1. Most likely snow totals based on updated qpf range from 3-5 inches across the southern half of the forecast area. LWX did upgrade to a warning just south of the MD line, but model guidance doesn't support a high confidence of widespread 6+ inch amounts across our area. Also, the heaviest snow is expected to fall overnight, then diminish by dawn, so expect improving road conditions and diminishing impacts during the morning commute. Any lingering light snow should taper off over southern Pa around or shortly after 12Z, as wave of low pressure passes off of the Mid Atlantic coast. A drier northerly flow will bring brightening skies by afternoon over northern Pa. Across the south, model RH profiles indicate a fairly thick cirrus deck will persist into the PM hours. Forecast soundings indicate mixing to at least 925mb, where ensemble mean temps of -6C to -8C support highs from the mid 20s over the northern mountains, to the mid 30s across the Lower Susq Valley. && .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/... Fast zonal flow over the Eastern U.S. is forecast to become more southwesterly early in the long term period downstream from the redeveloping upper trof over the Western U.S. Core of arctic air looks to remain along the U.S. - Canadian border with our area on eastern extent of coldest air. This will reinforce a baroclinic zone/temperature gradient along the East Coast through much of the long term period. Energetic southern jet stream will send ample shortwaves toward zone supporting the potential for several periods of winter weather across Central PA. The first of such system will be ongoing at the start of the long term period, impacting mainly southern portions of the region Thursday night. Any accumulations should be less than inch and confined to the Laurel Highlands. Another system appears to arrive over the weekend, with the best potential for snowfall accumulations late Saturday into early Sunday. There also remains at least some potential for a brief wintry mix in the Lower Susquehanna Valley. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... Medium range guidance continues to indicate Pa will remain in an active pattern in vicinity of baroclinic zone between an anomalous upper trough over the plains states and a ridge off of the east coast. Surface ridge building in from the Grt Lks should produce fair and chilly conditions Sunday into Monday. After that, a southern stream shortwave lifting out of the southern Miss Valley appears likely to impact Pa Monday night/Tuesday. Model timing has converged enough to support increasing POPs to near 75pct Monday night into early Tuesday. Latest ECENS and GEFS plumes indicate a wintry mix is most likely, as a weakening primary low tracks west of Pa and a secondary low passes off the Mid Atlantic coast. However, plenty of uncertainty remains with regard to surface low track and resulting type. Both ECENS meteograms and GEFS plumes support below normal temperatures through the first half of next week. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... Periods of visby AOB 1SM across southern half of CWA with an outside chance for conditions to drop near minimums for a short duration in the early morning hours. Bur snow ends early Thursday morning with improving conditions (MVFR to VFR range) by midday. Outlook... Fri...A.M. restrictions possible in snow/low cigs. Sat...P.M. restrictions possible in snow/low cigs. Sun...A.M. restrictions possible in snow/low cigs. Mon...Restrictions possible Monday night in mixed pcpn. && .CTP WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 8 AM EST Thursday for PAZ017>019- 027-028-049-050-052-058. Winter Weather Advisory until 9 AM EST Thursday for PAZ024>026- 033>036-056-057-059-063>066. && $$ SYNOPSIS...Steinbugl NEAR TERM...Fitzgerald SHORT TERM...Jurewicz/Gartner LONG TERM...Fitzgerald AVIATION...Steinbugl/RXR