textproduct: State College

SYNOPSIS

* Patchy light snow ending across areas east of the Susquehanna Valley early tonight, followed by another cold night. * A warming trend Tuesday into Thursday. * Winds will pick up by midweek with gusts of 30 to 40 mph possible at times from Wednesday into Friday with fast moving frontal systems. * Rain showers Thursday/Thursday night, perhaps tapering off as some snow early Friday, followed by colder weather.

NEAR TERM /UNTIL 8 AM TUESDAY MORNING/

The left/exit region/thermally indirect quadrant of a 105 kt upper jet did a dive SE across the CWA this afternoon and evening, bringing a few-several hour period of light snow and about 0.3-0.5 of an inch in many locations across Central PA and the Susq Valley. Just enough to slicken-up untreated roads for the late afternoon/evening peak commute hours.

It will be mainly dry with nothing more than a few flurries falling across the Northern and Western Mtns as the right entrance region of the aforementioned upper level jet passes by with some weak low-level WAA/isentropic and orographic lift.

We're looking at another cold night, with temperatures below normal, and mins in the single digits above zero up north, and 10 to 15F across Central and Southern portions of the CWA.

SHORT TERM /8 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/

A quasi split flow regime continues across the U.S. with the northern stream the stronger one containing relatively more progressive features moving across the Northern U.S. and Southern Canada. The temperate flow off the Pacific will and main storm track to the north of the CWA will limit the chance for any significant, widespread snow over the next week to 10 days with only brief spells of slightly below normal daytime temperatures and some mainly mountains snow showers with generally light accums.

A large scale pattern shift will support a west to southwest flow of milder air into the area by later Tuesday. The airmass is quite dry, so not expecting any rain or snow on Tuesday.

Wednesday will be milder and mainly dry. A cold front may clip the far north, but guidance is largely dry. Winds may gust above 30 mph during Wed afternoon.

Winds shift back to the southwest on Thursday and become gusty at times. Some showers later in the day, but snowpack is not real dense, and it has been dry too, so not seeing any issues with the amounts of rain. Peak temps of this warming trend - in the 40s to low 50s with departures averaging 8-12 deg F above normal, will occur on Thursday.

The rain could end late as some snow across the west and north. See long term section below.

LONG TERM /FRIDAY THROUGH MONDAY/

As noted above, the showers could mix with or change to some snow, before tapering off during the morning. A few flurries or snow showers could linger across the far west and northwest, but most areas should clear out by mid to late morning on Friday. Highs Friday will be back into the 30s with some lower to mid 40s southeast.

A series of warm fronts move back to the northeast for the weekend, so some chance of some precipitation. Some mixed precipitation could occur, mainly across the north. Amounts expected to be on the light side, with some spots perhaps not getting anything.

Some variation between the GFS and EC but both have 500 mb heights well above normal across the southern Great Plains into the gulf area. For the northeast states, this may taper the cycle of abnormally cold some. Harder call on the location of precipitation as one heads out in time.

AVIATION /03Z TUESDAY THROUGH SATURDAY/

The steady light snow ha moved east of the airspace with all TAF sites returning to VFR. RH progs for the night indicate VFR or even a cloud-free sky for much of the airspace over central PA. BFD will be the exception where MVFR cig is anticipated. The wind will slacken to <5kts and may even go calm in the valley locations.

High pressure will keep flying conditions fair and VFR for all of Tues. Another fast-moving and weak system zips through Tues night-Wed, but most of the time will be VFR and only BFD need worry about precip and lowered flight category.

Outlook...

Wed...MVFR cigs NW half. -SHSN VC BFD. VFR elsewhere.

Thu...Widespread SHRA occasionally reducing conditions to IFR. May end as a brief period of snow in the west. CFROPA Thurs night.

Fri...Gusty W wind. MVFR w/SCT SHSN NW. Mainly VFR elsewhere.

Sat...MVFR-IFR BFD in SCT -SHSN. MVFR cigs.

CLIMATE

Astronomical winter (solstice) begins at 10:03 a.m. on Sunday, December 21st.

CTP WATCHES/WARNINGS/ADVISORIES

None.