textproduct: State College

WHAT HAS CHANGED

* Excessive rain outlook areas adjusted for today.

KEY MESSAGES

1) A dry start to the day, but moderate to perhaps heavy rain expected later today into early Sunday.

DISCUSSION

KEY MESSAGE 1: A dry start to the day, but moderate to perhaps heavy rain expected later today into early Sunday.

Expect showers and storms to form later this afternoon into Sunday morning, as warm advection brings back the more humid airmass.

This will be followed by more showers and storms later Sunday afternoon and evening, as stronger dynamics and cold front work on the humid airmass.

Not a lot cold advection, abnormally warm and moist air take aim at the Great Lakes area again on Tuesday, as a strong upper level ridge builds northward from the TN Vly.

ERO for today adjusted to one area, and SPC outlook for Sunday trimmed across the southeast. Complex fcst, as been the case this summer.

Still holding off on a flood watch for now, given nothing going on yet on radar, still time to see how things play out later this aft.

More information below.

Guidance does put numerous heavy bands of rain over the area. FFG lower west and north, but heaviest QPF could be to the east. Also maybe things more an issue later Sunday, depending on where that rain falls today.

Again, the problem is: where? With uncertainty high as it is and FFG getting higher slowly, still holding off.

AVIATION /06Z SATURDAY THROUGH WEDNESDAY/

Per the last discussion, clouds will gradually overspread our area from SW to NE late tonight into early Saturday as a disturbance approaches from the Tennessee Valley. Confidence remains low in overnight fog given increasing cloud cover, with VFR conditions favored through the night.

Transport of plentiful moisture (PWATs of around 1.5-2") ahead of the disturbance will contribute to lowering cloud ceilings through the day on Saturday, beginning around the Alleghenies (KBFD/KJST/KAOO/KUNV) where S/SE flow may enhance cloud cover through upslope. Farther east (KIPT/KMDT/KLNS), VFR is favored for much of the daytime given the disturbance's slow eastward progression, with ceiling restrictions to mainly MVFR/IFR favored later in the evening and overnight.

Isolated showers are possible throughout the day on Saturday given ample moisture, with more numerous showers possible along the Alleghenies during the afternoon/evening due to upslope flow & convergence along the ridgeline. Given the moist environment, locally heavy rainfall with intermittent visibility restrictions (mainly MVFR-IFR) may accompany these showers. Later in the evening and through the night, showers are expected to congeal into a band of heavy showers and embedded thunderstorms as the disturbance begins to cross over the area. Embedded thunderstorms appear more likely at KBFD/KJST/KAOO where MUCAPE may rise to ~1000 J/kg, with lowering chances heading eastward.

Overnight, low stratus and areas of fog may develop and/or persist in the wake of this band of showers and storms, particularly near KBFD/KJST where skies may clear before sunrise & contribute to development of radiation fog.

Outlook...

Sun...Early MVFR/IFR and moderate rainshowers across the state. Additional SHRA/TSRA in the afternoon.

Mon...Primarily VFR conditions, with some potential for afternoon SHRA/TSRA.

Tue...Mainly VFR with a few showers possible over NW PA.

CTP WATCHES/WARNINGS/ADVISORIES

None.