textproduct: State College

WHAT HAS CHANGED

* Increased/darkened the sky cover grids across the board for the next 60 hrs * Increased winds and gusts slightly, especially over the east today and Sunday

KEY MESSAGES

1) Nor'easter will bring gusty winds and periods of rain for the first weekend of Fall

DISCUSSION

KEY MESSAGE 1: Nor'easter will bring gusty winds and periods of rain for the first weekend of Fall

Big storm will tuck itself between Long Island and NJ for the weekend. It will deepen to about 990mb depending on your numerical model/ensemble member of choice. At least one solution has the sfc low getting as far W as the Delaware River. Most keep the western extent of it's wobbly track around the Jersey Shore.

The wind already made a gust near 30KT at Wellsboro (KN38) around midnight and VAD Wind Profile from KCCX has 50KT winds not even 4kft aloft. KPHL has just gusted to 40KT (which is wind advy level). We may have to consider a wind advy, but current and previous thinking is that most gusts should stay in the 30s over our CWA. Lancaster, Lebanon, Schuylkill and Sullivan Counties are the most-possible locations to get a 40+KT gust. The gradient stays similar in tightness from mid-day today through Sunday evening.

Very light rainfall has already begun at PHL, and will work back to the west through the day. Expect some drops to hit the ground before 10 AM, and perhaps before 8 AM, in Lancaster Co. QPF is minor. The highest rainfall will be later tonight and through the day Sunday. Storm total numbers range from near 1" in New Holland and Dushore to less than a tenth of an inch from State College west.

As the nor'easter lifts to the northeast later Monday, conditions should steadily improve with temperatures poised to rebound above the historical average for the end of September.

AVIATION /12Z SATURDAY THROUGH WEDNESDAY/

Light rain is beginning to move into Central PA from the east as a strengthening Nor'easter continues to slowly lift northward off the coast. Rain will reach LNS by 14Z and will gradually expand westward through the morning, reaching MDT and IPT by the early afternoon. UNV is right on the western edge of where most guidance shows the rain getting to today, so we have included a PROB30 for a few hours this afternoon and evening. Any rain that falls today should be pretty light, so VFR is favored, though a brief drop to MVFR visibility is not completely out of the question. Northerly winds will quickly increase to around 15 knots this morning with gusts of 20 to 30 knots possible. The strongest gusts are expected to be in southeast PA and MDT and LNS may see a gusts of up to 35 knots.

A strong low-level jet will remain in place over most of Central PA through much of Saturday night, but the strongest winds may remain just above 2000 feet for most locations. Because of this, LLWS has been kept out of most of the TAFs. After a break in the rain during the evening, another round of steady rain moves in from the east as the surface low moves closer to the region. The biggest uncertainty in the forecast is just how far west this rain makes it during the day on Sunday. Ceilings should gradually drop to MVFR at MDT and LNS as the steadier rain moves in.

Outlook...

Mon-Wed...Improving conditions trending VFR by midweek.

CTP WATCHES/WARNINGS/ADVISORIES

None.