textproduct: Binghamton

WHAT HAS CHANGED

No significant changes with this forecast update. Only minor changes to temperatures, PoPs and QPF were made based on the latest available forecast guidance.

KEY MESSAGES

1)A slow moving upper level trough and mid level low move across the area Sunday through Monday night. This will bring unsettled weather, with periods of rain and thunderstorms. Some of the storms could produce gusty winds and torrential downpours. Isolated instances of flash flooding are possible due to slow moving, training thunderstorms.

2) Low amplitude weak upper level trough remains in place Tuesday and Wednesday. This will bring partly sunny conditions, with chances for a few pop up showers or t'storms along with generally seasonable temperatures.

3) The next trough and front is progged to slowly move through the area Thursday into Friday. This will bring increasing chances of showers and thunderstorms along with more warm and humid conditions.

DISCUSSION

KEY MESSAGE 1...

Expect a mix of mostly cloudy skies and areas of fog through mid morning today. Then, as the fog dissipates and daytime heating increases some pop up showers and storms should begin developing in the afternoon hours. It is a very slow moving setup, with 1000-700mb winds less than 10 kts, and converging along a boundary near or just north of the NY/PA border. Forecast soundings from the NAM show MLCAPE between 500-1200 J/kg across NE PA, with less than 500 J/kg across Central NY heading into this afternoon. Storm motions today will be very slow, really just drifting around at less than 10 mph; some of the storms could back build and/or become anchored to terrain with these slow motions and MBE vectors less than 15 kts. Warm cloud layer depths reach 10-12k ft across the Twin Tiers and Northeast PA this afternoon and especially into the evening hours. With PWATs between 1.8 to 2 inches, there is certainly the potential for slow moving showers and storms to produce very efficient, warm rain downpours later today into tonight. Outside of the showers and storms today will feature mostly cloudy and very humid conditions from the Twin Tiers south into NE PA where dew points will be in the low to mid 70s this afternoon. Further north, it will be less humid and warm with dew points in the lower 60s and high temperatures in the upper 70s to mid-80s areawide.

The atmosphere remains very well primed for more potential heavy to torrential downpours even overnight. An area of low pressure later this evening into the overnight hours will help to organize the rain and convection into a rotating cluster over parts of our CWA...exactly where remains uncertain...but seems to be targeting areas near and SE of Binghamton...especially NE PA and Sullivan County NY area. Some stripes of very heavy rain are possible during this timeframe, with the HREF starting to show up to 25% probability for 2"+ of rainfall over portions of the Poconos.

The periods of rain and some thunderstorms continue through the day on Monday. Instability will be much lower on Monday, as a cool maritime easterly flow takes hold. This should mean cooler temperatures in the 60s to low 70s much of the day, but saturated, with similar dew points and still very high pwats around 2" expected. This will lead to more periods of rain and a few embedded thunderstorms. Rainfall amounts may be even higher on Monday, with HREF 2"+ probabilities increasing upwards of 50-60% across NE PA and Sullivan County in this 24 hour period. A flood watch may eventually be needed if/when confidence increases on exactly where some of the heaviest, slow moving rain and storms will ultimately set up. Model guidance is showing the potential for 2-3 inches of rain across our NE PA and southern Catskill locations, with locally higher totals certainly possible. As mentioned above, Monday will be much cooler with highs only in the 70s, and an east wind around 10 mph.

KEY MESSAGE 2...

The upper level trough never really leaves the area entirely heading into Tuesday. However, it appears that the steadiest rain and storms will move east with the wave of low pressure. This setup will keep at least a chance for scattered showers and t'storms in the forecast, along with mostly cloudy skies. With all the clouds and scattered showers around, it stays on the cooler side as highs only reach into the 70s once again. By Wednesday, the latest ensemble forecast guidance shows mainly dry conditions aside from a stray pop up shower or two. Skies are also expected to become partly to mostly sunny and high temperatures warm up into the upper 70s to mid-80s.

KEY MESSAGE 3...

Thursday is forecast to be the warmest day of the upcoming week, as the area will be under a flat zonal flow pattern. Late in the day, the next shortwave trough is expected to approach from the Central Great Lakes region, bringing the chance for showers and thunderstorms. It will be partly sunny, warm and humid with highs forecast to reach well into the 80s across the region. Depending on the exact timing, the ensemble guidance still has the next front pushing through on Friday, likely bringing another round of showers and storms to the region. It will still be warm and humid, at least until the front moves through, with highs in the 80s once again. Looking further out, a lot of uncertainty remains for next weekend, with the NBM ensemble guidance showing low chances for showers or storms and very seasonable temperatures in the upper 70s to low 80s.

AVIATION /06Z SUNDAY THROUGH THURSDAY/

Low ceilings and fog will begin to develop at all terminals late tonight/early this morning with IFR to LIFR restrictions possible. There is uncertainty at ELM and BGM where no rain fell today. However, clear skies and light winds will be favorable for fog and/or low ceilings. Fog should lift by 12z Sunday with conditions improving throughout the morning. Rain showers and isolated thunderstorms will be possible at AVP tomorrow, which then may lead to additional restrictions. After this evening, winds become calm and stay light throughout this TAF period.

Outlook:

Sunday Night through Monday...Restrictions possible due to showers and possibly thunderstorms.

Tuesday...Mainly VFR with a chance for showers and isolated thunderstorms.

Wednesday through Thursday...Mainly VFR; showers and isolated thunderstorms possible late Thursday.

BGM WATCHES/WARNINGS/ADVISORIES

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