008 FXUS61 KBGM 210505 AFDBGM Area Forecast Discussion National Weather Service Binghamton NY 105 AM EDT Sun Jul 21 2019 .SYNOPSIS... The heat and humidity will persist into Sunday for Northeast Pennsylvania, with all other areas cooler. Showers and thunderstorms are possible Sunday into Monday as cooler air pushes into the entire region. Quiet weather settles in through the middle part of the week. && .NEAR TERM /THROUGH TODAY/... With the midnight update, we added some shower and thunderstorm chances to the forecast for the first few hours of the overnight across most of Central New York. This was to account for the decaying thunderstorm complex over Western New York. Most locations are still expected to stay dry through the overnight. 1030 pm update... The evening showers have pushed east out of the area. Now we are looking upstream to western NY and western PA where thunderstorms are moving in. Models have these dying before they get here as they push east into stable air. Minor changes made to old forecast. 630 pm update... Update to better depict the severe thunderstorms that formed across the far north and the far southeast. These thunderstorms will continue to the southeast and move out of the forecast area by 10 pm. 300 pm update... Main concerns in the near term remain centered around the heat and humidity for most of the area the rest of today, the Wyoming Valley and Upper Delaware Valley in ne PA tomorrow...and the potential for scattered thunderstorms this afternoon and evening...and again tomorrow morning along a southward sagging cold front, mainly from the srn tier of NY south. A flattened upper ridge and warm air mass remain situated over the area today with a weak cold front slowly drifting e/se through the region. Temperatures are struggling to make it into the lower 90s this afternoon, mainly due to the presence of a fairly thick layer of cirrus, but also due to cumulus clouds filling in where skies have cleared out. Dew points have reached into the mid to upper 70s...which has allowed heat indices to climb into the upper 90s and lower 100s. Most of the area still has another 2-4 hours of heating this afternoon...which could allow heat index values to top out around 105...especially in the lake plain, urban and valley locations. A few convective storm cells recently formed between ROC and SYR this afternoon, but have since dissipated. A fairly strong mid level capping inversion is likely the suppressive feature that has kept further development of showers and storms so far. The boundary layer should destabilize a bit more through the rest of the afternoon with surface based CAPE values above 3000 J/kg. Once the cap erodes enough to allow free convection, if there is enough time for additional heating, the potential for scattered thunderstorms will exist, especially across central NY from the Finger Lakes into the wrn Mohawk Valley and nrn Catskills. A few of these storms may produce strong wind gusts and heavy downpours. Afternoon/evening storms should move east out of the area before midnight prior to a secondary front which is expected to drop into the area late tonight into Sunday morning. There is still some uncertainty with respect to what develops along this boundary. Most of the high-res model guidance is hinting at a decaying convective system moving either south or north of the forecast area...keeping us mostly dry. Will keep with a chance of showers/storms moving across the area tonight and lingering from the srn tier of NY into ne PA through the day Sunday as the front stalls out. The air mass behind this front will be much cooler and drier...with temps and dew points ahead of the front remaining in the lower 90s and lower/mid 70s respectively. This will still allow for heat index values in the 100-105 deg range for the Wyoming Valley and Upper Delaware Valley. An Excessive Heat Warning remains in effect for this far southern area through 8 pm Sunday. && .SHORT TERM /TONIGHT THROUGH TUESDAY/... Cold front stalls just south of the area early Monday and becomes the focus for convection as a wave moves northeast along it. Models differ, of course, in the placement of the front and associated rain but as an average expect showers and thunderstorms redeveloping Monday, especially over the southeast two thirds of the forecast area. Deep moisture available so any storms that do develop could produce heavy rain, and with the southwest flow through the column, training cells also possible. Surface low moves into New England Monday night and early Tuesday as an upper wave rounds the short wave trough kicking the whole business eastward. Expect improving conditions Tuesday with showers ending from east to west during the day. It will be cooler both days, so some relief from the heat with clouds and showers. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... The long term will be a generally dry and cooler period with with a long wave trough over the area and surface high pressure nosing in from the southwest. With the lowered heights aloft and heating, some instability showers are possible during he afternoon almost any day, with the best chance over the NY counties, especially the higher ground. Temperatures through the period will be near or slight below the seasonal norms, but much lower the extreme heat of late. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... VFR through most of the overnight. However, the likelihood is increasing for an area of MVFR stratus to form toward sunrise for all NY terminals. The highest probabilities are at KSYR and KRME. Stratus should burn off through the mid-morning hours today. By this afternoon, winds will pick up a bit to around 10 knots with a few gusts pushing 20 knots from the west. A few afternoon and evening thunderstorms may develop around KAVP but the coverage and timing is still too uncertain for mention in the 06Z TAF. Outlook... Tonight... Generally VFR. However, a thunderstorm or two is possible around KAVP. Monday through Monday night...Rain and restrictions likely as wave of low pressure moves up along front just to our southeast. Embedded thunder possible as well. Tuesday through Thursday...Mainly VFR other than valley fog for at least KELM in the predawn hours Wednesday and Thursday mornings. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...Excessive Heat Warning until 8 PM EDT this evening for PAZ044- 047-048. NY...None. && $$ SYNOPSIS...BJT/TAC NEAR TERM...BJT/MWG/TAC SHORT TERM...DGM LONG TERM...DGM AVIATION...MWG