935 FXUS61 KBGM 280759 AFDBGM Area Forecast Discussion National Weather Service Binghamton NY 359 AM EDT Mon Jun 28 2021 .SYNOPSIS... Tuesday is expected to be hot and humid with the heat index getting well into the 90s. Afternoon thunderstorms are possible today through Wednesday. Cooler and more unsettled weather will return to the region for the end of the work week. && .NEAR TERM /THROUGH TUESDAY/... 400 AM Update... Hot and humid weather continues today and tomorrow but there will be some relief with afternoon thunderstorms. Overnight lows stayed in the 70s in most locations where there was clearing but areas that were cloudy have not even fallen below 80. Dew points are expected to be a few degrees warmer than yesterday so the heat index approaches the upper 90s and even a few 100s in the river valleys. As 500 mb heights fall and a weak boundary slowly moves southward through NY, thunderstorms fire off along the boundary in the early afternoon along the NY thruway and moving south through the afternoon and early evening. While there will be 1000-2000 J/kg of CAPE tomorrow, the 0-6 km shear is only 10-15 knots and moist mid levels, severe threats are minimal. Thunderstorms will not be fast moving and PWATS over 1.5 inches and long skinny cape through deep warm cloud depths, rain rates will be high. HREF max QPF from the CAMs show small pockets of up to 2 inches of rain in 3 hours so any locations that get a direct impact by the slow moving thunderstorms could see a good gully washer. Tonight, the thunderstorms that developed dissipate with the loss of day time heating. High dew points and cloud cover keeps overnight lows in the upper 60s and low 70s once again. Lows may need to be bumped up a few degrees where the thicker clouds set up based off of temperature trends from tonight but confidence is too low as to where the thickest clouds will be so no further adjustments were made to the lows. Tomorrow will be very similar to today. Temperatures reach the upper 80s to low 90s with dew points in the upper 60s and low 70s. More CAPE is expected to develop but upper level dynamics are similar to Monday so severe thunderstorms are not expected. With more energy to work with, thunderstorms will be more widespread with high rain rates once again with any cell. && .SHORT TERM /TUESDAY NIGHT/... A frontal boundary will be located to our north with a high pressure system off the Mid-Atlantic coastline. This will continue to bring warm and moist air into the region. With the front inching closer lift will be a bit more to aid in the development of a few afternoon and evening thunderstorms. Shear is modeled to be lacking but plenty of instability and high PW values are in place. This will keep the focus to locally heavy rainfall and a downburst of wind or two with a couple of thunderstorms. Storm motions also look very slow another concern for heavy rain. Outside the thunderstorms, another hot and humid day will be on tap with modeled boundary temperatures indicating once again quite a few locations see 90 for high temperatures. with more clouds some locations in CNY may the spared another 90 degree day. With the combination of heat and humidity, heat index values are a concern again with top values around 95 in NE PA and the Southern Tier of NY. Drink plenty of fluids, take breaks and wear loose/ lightweight clothing if outdoors. A muggy night Tuesday night with temperatures only falling back to around 70. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... A broad trough will be in place across the region Wednesday with a cold frontal boundary across northern New England. Instability and moisture will continue to be advected into the region behind the departing high pressure offshore. A key difference though Wednesday will be the increase in 0-6 KM bulk shear to around 30 knots. Once again afternoon thunderstorms should develop but be a bit more organized and progress southeast through the area into the evening hours. Locally heavy rainfall ( PW values around 1.7) is still a threat but storm motions look a bit faster compared to Tuesday. Soundings do show some indication of a downburst/ gusty wind potential with some storms. With more clouds high temperatures should start to trend a few degrees cooler after another muggy morning Wednesday with lows around 70. Our region continues to be in a battleground between an upper level low to our west and a high pressure system offshore with a frontal boundary overhead. Moisture will continue to be transported and lifted along the front for rounds of showers and some thunderstorms through at least Friday. Heavy rainfall threats may materialize again. It is important to note quite a bit of spread was present between various ensemble members on how quickly the front and upper level low move east of the area. For now, given the uncertainty we linger shower chances through the 4th of July weekend. Temperatures should continue a slow cooling trend by a couple of degrees each day. && .AVIATION /08Z MONDAY THROUGH FRIDAY/... VFR conditions are expected to continue through the overnight hours into tomorrow morning. With the hot and humid weather tomorrow, instability builds and thunderstorms develop across central NY in the afternoon. A boundary sagging south through the afternoon brings an earlier threat to SYR and RME (between 18z and 22z), and a later threat to ITH, ELM, and BGM (between 20z and 2z). Loss of day time heating will likely cause storms to fizzle out before reaching AVP tomorrow evening. While there is higher confidence that there will be thunderstorms tomorrow afternoon the timing is still uncertain and will be tweaked in the 12Z and 18Z updates. Outlook... Monday night through Tuesday...Scattered thunderstorms will persist in the early evening hours, becoming more isolated after midnight. Locally heavy rain will be the main threat here so visibilities could drop to IFR during these storms. Wednesday through Thursday...Again mainly VFR but restrictions likely in showers and thunderstorms especially in the afternoon. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...None. NY...Heat Advisory from 11 AM this morning to 8 PM EDT this evening for NYZ016>018-024-025-055-056. && $$ SYNOPSIS...AJG/DJN NEAR TERM...AJG SHORT TERM...MWG LONG TERM...MWG AVIATION...AJG