textproduct: Binghamton

WHAT HAS CHANGED

A Severe Thunderstorm Watch has been issued for nearly all counties until 9 PM this evening. Locally strong to severe thunderstorms this afternoon and evening can produce damaging winds and hail, but an isolated weak tornado can't be ruled out.

KEY MESSAGES

1) Showers and thunderstorms will track across the area into tonight. Some storms can be severe with damaging wind gusts, large hail and possibly an isolated weak tornado. Heavy downpours are also expected and localized flash flooding will be possible.

2) Mainly dry weather is expected Friday through the weekend as high pressure builds in.

3) A few rounds of showers and thunderstorms are expected to return Monday through midweek.

DISCUSSION

KEY MESSAGE 1...

After the relatively cloudy start to the day, there has been enough clearing and instability to allow showers and thunderstorms to develop this afternoon well ahead of an approaching cold front. Current mesoanalysis shows 1000-1500 J/kg of MLCAPE, 2000-2500 J/kg of SBCAPE, steep low-level lapse rates, 0-6km bulk shear around 30 knots and some pockets of 0-3km SRH of 100 m2/s2 across the CWA. As a result, some locally strong to severe storms have developed with damaging winds and large hail the main concerns. Given a little bit of spin in the low-levels, an isolated, weak tornado cannot be ruled with any storm.

The severe storm threat is expected to shift from the Finger Lakes Region into the Southern Tier, NE PA and the southern Catskills as the rest of the afternoon/evening progresses. There is the potential for localized heavy rain with PWATs around 1.40-1.50 inches and some potential training of showers and storms as well. This does lead to an isolated flash flood risk, with some storms lining up currently along the southern/eastern Finger Lakes, and later on this evening in the Catskills and portions of NE PA.

While the severe threat looks to wane by 9-10PM this evening, showers an an additional isolated storm are expected to linger into the overnight before diminishing. The actual cold front itself is expected to move through tomorrow morning.

KEY MESSAGE 2...

As the cold front continues to push east tomorrow and high pressure starts to builds in at the surface, the upper level trough will still be lagging overhead. This can lead to an isolated shower or two, mainly through midday and across the higher terrain of CNY before noticeably lower PWATs settle in and dry conditions are expected the rest of the day and through the upcoming weekend.

High temperatures tomorrow and Saturday will be mainly in the mid and upper 70s. Sunday is expected to trend warmer as the flow becomes more westerly with highs in the upper 70s and lower 80s.

KEY MESSAGE 3...

A frontal boundary approaching from the north on Monday may stall out near the area through the first part of next week. This can lead to multiple rounds of showers and thunderstorms through Wednesday. During this same timeframe, the northern periphery of a building ridge is also expected to be near or over the CWA allowing for a few waves of energy embedded in the flow to move through enhancing the risk for scattered showers and thunderstorms. High temperatures early next week look to be mainly in the upper 70s and low 80s.

AVIATION /19Z THURSDAY THROUGH TUESDAY/

Scattered showers and thunderstorms this afternoon will likely result in restrictions. 2 hour TEMPO groups for TSRA were included during the timeframe where thunderstorms are most likely for each terminal. Amendments may be needed to adjust timing or to add in lower restrictions.

After the thunderstorm activity ends this evening, widespread fog/mist is expected to develop, especially across areas that received rainfall today. Restrictions will gradually dissipate by the mid-morning on Friday.

Outlook...

Friday afternoon through Sunday...Mainly VFR.

Monday through Tuesday... Scattered showers and thunderstorms possible with associated restrictions, especially each afternoon.

BGM WATCHES/WARNINGS/ADVISORIES

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