textproduct: State College

WHAT HAS CHANGED

* SVR Watches are done.

KEY MESSAGES

1) Thunderstorms winding down this afternoon. Additional storms are expected into the evening, but will be much less trouble.

2) Humid with rounds of heavy showers and strong thunderstorms focused over southwest Pennsylvania through midweek

DISCUSSION

KEY MESSAGE 1: Thunderstorms winding down this afternoon. Additional storms are expected into the evening, but will be much less trouble.

Just a couple of showers across Clinton and Lycoming Counties at 5 PM, and while they have lost their lightning, they are spinning and one has split into two. So, we'll continue to keep an eye on them. Most of the showers and a few storms will stay over the western third of the state for the rest of the night. Just an isolated SHRA/TSRA is expected elsewhere.

Previous...

MCS moving off to our E at 4 PM. Only a few of the SE Counties are left in the watch, as they still have some potential left for severe wx. Some instability remains across the rest of the CWA. But, that is of no concern for severe wx. Can't rule out a heavy downpour out of one of these stragglers or something that may develop this evening. But, the overall threats for SVR and FF are very low.

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KEY MESSAGE 2: Humid with rounds of heavy showers and strong thunderstorms focused over southwest Pennsylvania through midweek

Model trends are focusing primary risk for severe storms and heavy rain across southwest PA on Tuesday. This area lies closest to the equatorward edge of the westerlies within very moist instability gradient. SPC and WPC have outlooked this area (SW PA) with a a level 2/5 severe storm risk and 2/4 excessive rain risk.

Rounds of showers and storms remain possible through midweek. Multiple shortwave disturbances will traverse the northern tier and interact with a slow moving frontal zone. The combination of rich low level moisture, instability and repeated forcing along the boundary will support some potential for periodic clusters of storms with locally heavy rainfall. WPC excessive rain outlooks (EROs) have shifted farther to the south/west and only clip the far southwest portion of the CWA on days 3-5 or Wed-Fri.

The end of the week into the start of the weekend looks less humid (more refreshing) as push of relatively cooler and drier air accompanies seasonably strong/Canadian high pressure building southeast from the Upper Midwest.

AVIATION /00Z TUESDAY THROUGH SATURDAY/

A few showers linger in Central PA, but any isolated overnight -RA is most likely from upslope effects at JST and BFD.

Conditions will waffle between MVFR and VFR this evening through the overnight hours as low level moisture remains over the area. Patchy -RA is possible over the higher elevation airfields through the morning hours. Widespread fog development and IFR visibilities is only confident at BFD. Elsewhere, low level moisture content may be enough for some mist and some MVFR visibilities, but confidence isn't high enough for anything lower at this time.

MVFR conditions continues into the morning with an improvement to VFR in the later morning/early afternoon. Isolated to scattered afternoon thunderstorms are possible, but confidence isn't high enough for impacts at any one site yet, restrictions are possible though. Storms moving in from the northwest may cause restrictions towards the end of the forecast period at JST and AOO.

Outlook...

Mon-Thu...Scattered showers/storms. Restrictions possible.

Fri...Mainly VFR. A few showers or storms possible over southwestern PA.

Sat...Mainly VFR. Isolated shower/storms possible in the afternoon.

CTP WATCHES/WARNINGS/ADVISORIES

None.