textproduct: Binghamton

WHAT HAS CHANGED

No significant changes. Tuesday is still anticipated to be our most active day for this week.

KEY MESSAGES

1) Thunderstorm chances return Tuesday, especially afternoon through evening, as the next frontal system passes. A few storms may be strong to severe with locally heavy rainfall.

2) Some showers may linger Wednesday, otherwise a generally dry period is anticipated for the rest of the week with modest warming into the weekend.

DISCUSSION

KEY MESSAGE 1...

After another dry day with departing high pressure today, a broad upper level trough will set up over the Great Lakes by Tuesday morning. A deep 990s mb surface low over Canada will drag the next frontal system through. A surge of moisture ahead of the leading warm front will help support scattered showers and isolated thunderstorms. Following the warm front, a cold front will eventually push through, though the timing of its passage remains a bit uncertain and may lag. A pre-frontal trough ahead of the primary front may turn out to the be the main focus for thunderstorms Tuesday afternoon-early evening. Model guidance varies greatly on instability Tuesday afternoon, ranging from just a few hundred to over 1000 J/kg of MLCAPE. Strong flow aloft will enhance the shear with values expected to be 40 to 50 kts based on most guidance. Even with the wide range of instability values, conditions look favorable for another round of strong to severe storms. While all hazards look to be possible, the highest confidence is with strong gusts being the main concern. The Storm Prediction Center maintains a severe thunderstorm risk for our region.

Precipitable water values are projected into the 1.5 to 2 inches range and warm cloud depths will be 10 to 12 thousand feet, which would favor heavy rainfall at times. Training of thunderstorms would also be a concern. If the pre-frontal trough causes most convection to exit, than the progressive nature of the cells may mitigate the excessive rainfall threat. However, if additional showers-embedded storms linger back with the front itself then there could be repeated batches to cause potential issues. Weather Prediction Center continues to highlight the area in at least a lower end risk for excessive rainfall Tuesday. Given that some locations received over 2 inches of rainfall with the last storm system, antecedent conditions will be more favorable for localized hydro issues in poor drainage areas despite a couple of dry days in between.

KEY MESSAGE 2...

The upper level trough will dig into the Eastern Great Lakes and with a trailing shortwave Wednesday that could support additional showers in addition to cooler temperatures. High pressure and drier air will build in as the trough slides east, cutting off any remaining showers by Wednesday night.

Surface high pressure will be in control for the second half of the week with generally dry conditions. Temperatures will still be somewhat below average Thursday but will trend modestly warmer by the weekend with highs mostly in the 80s as weak ridging occurs aloft. There is uncertainty for whether weak waves embedded in the ridge could manage small shower/thunder chances by late in the weekend; the dryness of the air may be too much to overcome. While it remains uncertain if wildfire smoke will return late this week, the pattern of a ridge out west and trough in the east would be favorable flow for off-and-on smoke at times over the Northeast.

AVIATION /06Z MONDAY THROUGH FRIDAY/

VFR conditions across the region as high pressure is in place, with these conditions lasting through the TAF period for much of the region.

Some high level cirrus clouds are streaming overhead, which will limit some cooling over the next few hours, but they should clear out and allow valley fog to develop just before sunrise. ELM should see some periods of IFR and lower restrictions due to the fog. Confidence in it developing is only moderate given the very dry airmass in place but with current temps and dewpoints near the crossover thresholds now, thinking is that we will see enough cooling after the cirrus clouds pass to generate a short period of fog around ELM. ITH also has a chance for some fog this morning, but with winds remaining active, we should only see a few instances of MVFR restrictions later this morning if we can get some periods of calm winds.

Outlook:

Monday night...Mainly VFR; a low chance of showers spreading up from the south late.

Tuesday and Wednesday...A chance of showers and thunderstorms along with associated restrictions.

Thursday and Friday... Mainly VFR.

BGM WATCHES/WARNINGS/ADVISORIES

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