textproduct: State College

WHAT HAS CHANGED

* Winter Weather Advisory expired at 1PM * Lowered Max temps and raised Min temps this weekend

KEY MESSAGES

1) Breezy and colder weekend with rain and snow showers downwind of Lake Erie

2) Another extended stretch of dry and seasonal weather next week

DISCUSSION

KEY MESSAGE 1: Breezy and colder weekend with rain and snow showers downwind of Lake Erie

Another vorticity lobe currently over NW PA per satellite imagery will swing through the mean trough across CPA and drive a reinforcing shot of cold air advection (CAA) to the southeast or downwind of Lake Erie. The CAA along with a more favorable W/NW low level wind trajectory will promote lake effect precip this weekend across the Northwest Allegheny Plateau and Laurel Highlands. Snow accumulations will generally be less than an inch and limited to the higher terrain, though isolated amounts of up to 2 inches will be possible by Sunday morning in areas that see the most persistent snow bands. Brisk winds also through the weekend will add a winter-like chill factor with max gusts in the 20-30 mph range.

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KEY MESSAGE 3: Another extended stretch of dry and seasonal weather next week

Lake effect rain and snow showers come to an end by Monday morning as an upper level ridge builds into the region. High pressure at the surface and aloft will provide dry conditions with mainly clear skies for next week along with moderating temperatures. Highs should reach the 55-65F range by the second half of next week or +10-15 degrees above the historical average for mid November.

AVIATION /18Z FRIDAY THROUGH WEDNESDAY/

Upper low pretty much overhead. Comma head precip barely to the east of IPT and should be moving eastward and out of the CTP airspace by 22Z. Gusty NNW wind is the major issue right now. But, as the flow in the 2-10kft layer backs a bit more behind the upper low (also moving east), lake effect precip should begin to get into BFD. But, the fetch is still not all that favorable. BFD should see a gradual lowering of the cig to IFR overnight as snow becomes ocnl. We often forget just how quickly snow can lower visby as we first start into winter. To that end, we've tried to get ahead of that trend and bring visby down to IFR at BFD just after sunrise. The cross-lake flow becomes very favorable on Sat (and for the next 24 hrs) for a long band or two drop off LH and across LE and slide right up into Somerset and Cambria counties. Thus, JST will be at risk for much more IFR/LIFR vs even BFD Sat into Sun mid-day. Just how bad the visby and cigs get there will be dependent on the exact position of that band (or bands) with the Huron connection. At this point, we'll put in mentions of IFR.

Elsewhere, it should stay MVFR or better at AOO, UNV and IPT with only a flake or two of snow this weekend. MDT and LNS look more like VFR. The clouds could lower to MVFR at some point Sat in those SE terminals.

Later Sunday, the lake moisture goes away while the inversion lowers, too. VFR follows.

Outlook...

Sun...VFR, gusts NW 15-25KT.

Mon-Wed...VFR.

CTP WATCHES/WARNINGS/ADVISORIES

None.