415 FXUS61 KBGM 220532 AFDBGM Area Forecast Discussion National Weather Service Binghamton NY 132 AM EDT Mon Jul 22 2019 .SYNOPSIS... A cold front is moving through this evening, bringing in cooler weather for Monday. An area of low pressure will move along the cold front to bring our area a round of rain Monday and Monday night. High pressure with drier weather builds into the region for the middle and end of the week. && .NEAR TERM /THROUGH TODAY/... Several clusters of showers and thunderstorms will continue moving slowly northward along an instability gradient through the overnight. This instability gradient will give way to more in the way of synoptic lift to increase the coverage of showers and rumbles of thunder toward sunrise. Modeling has been poor with the coverage of showers and thunderstorms so far during the overnight hours, so forecast confidence is not ideal. Shower and thunderstorm coverage should slowly creep into the rest of NE PA and into western portions of the Southern Tier by sunrise. This looks a bit faster than previously indicated. 1030 pm update... Again only minor adjustments. A few showers in Luzerne only with thunderstorms just to the west. This should push south for tonight by 1 am. Cool dry air continues to push south tonight. 630 pm update... Only minor adjustments made. showers and thunderstorms have mostly moved out of NEPA and south central NY now. A few light showers are possible in NEPA and Sullivan County NY this evening. Drier air on the way in behind the front. Dewpoints are dropping into the 50s. 300 pm update... Main concerns in the near term remain focused on the continued heat and humidity the rest of today from the srn tier of NY south into ne PA...the threat of showers and storms, some possibly strong today...and then the onset of more rain with some embedded thunder possible through the day Monday, tapering off Monday night west to east. A lingering warm air mass with modest humidity remains draped across the srn portions of the forecast area today with cooler and drier air pushing in from the north. Temperatures only into the lower to mid 80s to the north...but into the upper 80s and lower 90 from the srn tier south, with dew points in the lower 70s. Highest heat indices 100 to 105 through the Wyoming Valley this afternoon. Weak surface boundary stretched w-e across PA this afternoon is expected to interact with an increasingly unstable air mass this afternoon and early evening to produce scattered showers and storms. SB CAPE values around 2000 J/kg and a weak amt of 0-3km shear will likely be sufficient for convective initiation. As of 3 pm, already starting to see some weak development across n-central and ne PA. Some of these storms will strengthen...with the main concerns being heavy downpours and gusty winds. These storms should be mainly diurnally driven...so as sunset approaches the intensities will ramp down. The pattern will change tonight as an upper trough digs east through the Great Lakes. As this wave amplifies, a strong 100 kt jet will set up to our north and a strong supply of moisture from the deep south will get advected into the area. The strong upper level dynamics and moisture will allow rain to develop later tonight and early Monday morning. Rain is expected to continue through the day with only a weak amt of elevated instability over the sern portions of the forecast area possibly triggering a few embedded weak thunderstorms. Will likely be mostly a stratiform rain event that could lead to widespread 1 inch amounts...and locally 2+ inches by the time the event winds down Monday night. At this time, we are not expecting any significant impacts from this rain event. Temperatures on Monday will be noticeably cooler and drier with highs only topping out in the lower to mid 70s...and dew points in the upper 50s and 60s. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY/... A few lingering showers are possible early Tuesday as the front continues to move east. In the afternoon, some instability is created as the upper trough swings through allowing the heating to develop a few showers. Late in the day and overnight, loss of heating will bring any light convection to an end. Upper trough moves east on Wednesday with the axis over the eastern NY border. There is the risk of isolated showers over eastern NY during peak heating but most of the area will be dry. Temperatures both day will be a few degrees below normal with the northwest flow and upper trough. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... Much of the long term features a building surface ridge and northwest flow aloft under a broad trough. This will result in near normal temperatures and the outside chance of a shower as a result of some limited daytime instability. By saturday, the upper trough relaxes a bit and the upper flow becomes more zonal. However, surface ridge remains in place so forecast should remain dry. && .AVIATION /05Z MONDAY THROUGH FRIDAY/... A cluster of thunderstorms looks to move through the KAVP area around the start of the TAF period around 06Z. Some restrictions are anticipated here. However, the ending of TEMPO may be a bit later than when the thunderstorms actually end. Will monitor if amendments are needed in the next couple of hours. Elsewhere, VFR conditions will gradually give way to developing MVFR and even IFR ceilings with showers by this afternoon. Timing of the MVFR and IFR ceiling and visibility restrictions still has some uncertainty but the general downward trend is expected. Even though the showers by this evening IFR to MVFR ceilings should persist through tonight. Outlook... Tuesday through Friday...Mainly VFR other than valley fog for KELM in the predawn hours. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...None. NY...None. && $$ SYNOPSIS...BJT/TAC NEAR TERM...BJT/MWG/TAC SHORT TERM...DGM LONG TERM...DGM AVIATION...MWG