textproduct: Binghamton

WHAT HAS CHANGED

Significantly lowered shower and thunderstorm chances for Thursday afternoon across northeast Pennsylvania, as very dry air pushes in after a morning wave pushes through. Also, increased wind gusts across the entire area Thursday morning through the afternoon.

KEY MESSAGES

1) An upper level trough will bring rounds of showers and storms today, especially east of the I81 corridor.

2) Frontal system will push through the region tomorrow with more chances for showers and thunderstorms. Greatest chance for widespread showers and storms will be during the morning, with higher chances across north central NY during the afternoon.

3) High pressure pushes in on Friday with cooler and drier conditions through the weekend.

DISCUSSION

KEY MESSAGE 1...

A weak short wave will cross the region early this morning with a few showers and possibly some embedded thunder. There should be a lull in shower activity until early this afternoon before another weak wave pushes in this afternoon. There will be some instability available this afternoon, but with only a few hours of sun it will be limited. Current model soundings are showing MLCAPE at 400-500 J/kg. This still should be enough for at least a few thunderstorms this afternoon and early this evening, especially east of the I81 corridor. However, shower activity will quickly dissipate around sunset as the wave pushes east.

KEY MESSAGE 2...

There will likely be a lull for few hours tonight between an exiting wave and a warm front pushing in from the west-southwest late tonight. Showers and thunderstorms associated with the warm front move in late tonight through Thursday morning. These showers and storms could be from a remnant MCS that pushes across Michigan this evening. Either way, the timing of this feature in our region is not good for severe thunderstorm potential on Thursday. After these morning showers and storms push through, a dry slot pushes in, with very dry air from the Southern Tier southward showing up on NAM and GFS forecast soundings Thursday afternoon. Model soundings show a well mixed boundary layer and very dry air with inverted V in the lower 5K ft. This and a tightening thickness gradient just out ahead of an approaching cold front will likely produce gusty winds from late Thursday morning through early afternoon. Wind gusts up to 50 mph will be possible and would be locally higher across areas of complex terrain, but confidence at this time is too low for a wind advisory. As for the severe thunderstorm threat, the timing of convection in the morning and then the arrival of a dry slot will limit shower and thunderstorm activity in the afternoon and the suggestion was made to SPC for a removal of the Slight Risk from our southern CWA. Although, further north, weak instability will still be available in the afternoon and with the strong winds fields, could certainly see some potential for a few severe thunderstorms across Central NY.

Winds diminish Thursday night as cooler air filters in behind the front, with temperatures falling into the mid to upper 50s.

Key Message 3...

Surface high pressure will build in behind the cold front for Friday. This will bring drier and cooler conditions through the weekend with low humidity. However, there will remain some upper troughing over the region, so can't rule out some diurnal shower and thunderstorm activity around the peak heating hours of the afternoon. The next chance for widespread rain will come towards the beginning of next week, but any thunderstorm potential with this next system is uncertain at this time.

AVIATION /06Z WEDNESDAY THROUGH SUNDAY/

VFR conditions expected across all terminals through the early morning hours. A trough of low pressure moving in from the west will butt up against the ridge departing to the east, keeping winds mostly active through daybreak. These active low level winds should be strong enough to prevent fog from forming and keep conditions VFR.

Rain showers will move into the area later today, with most model guidance now showing scattered showers and perhaps an isolated thunderstorm moving through during the afternoon hours; mainly in the 19z to 23z timeframe.

Outside of any showers or thunderstorms it is forecast to remain VFR through the day and into tonight, with SCT to BKN cloud decks between 070-150 ft agl expected. With the scattered showers or isolated thunderstorms brief restrictions are certainly possible, especially visibility. At this time confidence on timing, coverage and placement was not high enough to include any TSRA in the tafs; covered the potential with -shra and VCSH instead.

Winds will be light southeasterly overnight around 5 kts, turning southwest later today between 6-12 kts, with a few higher gusts possible at times. Winds turn back to southeasterly tonight, under 10 kts through the end of this taf period.

Outlook:

Thursday and Thursday night... Restrictions from showers and thunderstorms likely. Very breezy, southwest winds become westerly. Timing still uncertain with restrictions and wind shifts. Low Level Wind Shear possible in the morning.

Friday through Sunday...Possible intermittent restrictions from scattered showers; breezy with westerly wind gusts each afternoon.

BGM WATCHES/WARNINGS/ADVISORIES

PA...None. NY...None.