922 FXUS61 KBGM 311806 AFDBGM Area Forecast Discussion National Weather Service Binghamton NY 206 PM EDT Thu Aug 31 2017 .SYNOPSIS... A cold front will drop through the region today bringing showers to the southern tier and northeast Pennsylvania into the early afternoon. Friday and Saturday will be primarily dry but cool, followed by a wet Saturday night into Sunday morning. && .NEAR TERM /THROUGH FRIDAY/... 1020 am update... Local radars show widespread showers across the southern tier and the western Catskills which is immediately behind the cold front. Raised pops into the likely category for the next couple of hours in the southern tier and northern tier of Pennsylvania and this boundary continues dropping south. The activity is over for the northern forecast area and will end in the southern tier during the early afternoon. Due to extensive cloud cover and lack of any instability removed the mention of thunder. 6 am update... Update to speed up the cloud cover and reduce the pops. Most of the light showers will stay in the western half of the NY counties. Temperatures already showing a response to the increased winds and rising into the 60s. 3 AM Update... Showers already moving into central NY well ahead of a cold front. These isolated showers will stay mostly in the northeast CWA and weaken. Cloudy skies are also pushing south into the region. Further south is river valley fog in south central NY and northeast PA. Behind the cold front over Lake Ontario is a band of mainly light showers. This will move south into the Finger Lakes around sunrise. By afternoon it will be in northeast PA then out of there by 5 PM. The band of showers will become less numerous as it moves south. Weak heating in NEPA and the Catskills could be enough to cause an isolated thunderstorm. Models not showing much instability and only weak forcing. Rainfall amounts will be mostly under a quarter of an inch. Behind the front is good cold air advection. Temperatures will not recover much in the far north despite some sunshine. Mid 60s north to low 70s far south. This evening skies become partly cloudy. Airmass will continue to dry and cool with 850mb temps falling to 0C. Lows will drop to the upper 30s far east and northeast to low and mid 40s elsewhere. Not seeing much fog with the dry advection. Friday high pressure centered over the Great Lakes will keep it mostly sunny. With the cold Canadian airmass highs only in the low and mid 60s. && .SHORT TERM /SATURDAY THROUGH SUNDAY/... 200 PM UPDATE... The remnants of Harvey will be approaching the region from the Tennessee Valley on Saturday, however, there will be a rather dry Canadian high pressure system over CNY and NEPA. This dry air will eat away at the leading edge of the tropical remnants and much of Saturday looks to be dry with increasing cloudiness across most of the forecast area. Do have a low chance of rain working into mainly NEPA by early evening (00Z). The tropical remnants get swept up in a northern branch trof pushing through the Great Lakes region and should be a quick hit of high confidence rainfall moving through on Saturday night and the first part of Sunday. Timing in the models is pretty good on the beginning phase of the event, but there is some discrepancy as to exactly when rain moves out. Have made some adjustments to the PoP timing, but even with the downward adjustment during the afternoon period, Sunday may trend drier faster than the current forecast. Nudged temperatures up a tad on Saturday with anticipation of less rainfall, and also kept overnight lows up higher than guidance given clouds and rain moving into the area. Close to guidance on Sunday, but still cooler than normal. && .LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/... 200 PM UPDATE... High amplitude mid level trof begins to develop during this time frame and will move over the area by Wednesday. Interactions with tropical system Irma closing in on the western Atlantic may help to beef up the downstream ridge. Models already showing trends of slowing down the cold front approaching us from the Great Lakes region for Tuesday. Have pushed PoPs back into Monday night and lowered slightly, especially in the southeastern zones. Front should be bringing showers and a chance of thunderstorms for Tuesday. Models then diverge further into the week with placement of the front and where it may stall, or drift back west. Most medium range models push the front through our area with the GFS most progressive through Thursday morning. ECMWF and Canadian Global are also to our east, but are showing hints of developing low pressure aloft within the high amplitude trof and lifting it north. Will have to see what the trends offer up, but stalling the front further westward across the Eastern CONUS may turn out to be the answer going forward as Irma moves closer to the U.S. by next weekend. The short answer is we continue to mention chance PoPs across the forecast area (especially east half) from Wednesday through Thursday. Overall, temperatures below normal next week with a small surge of near normal temperatures on Tuesday ahead of the cold front. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/... Cold front has cleared the terminals ending the possibility of any more showers. Conditions through this afternoon will be primarily low VFR with ceiling around 4K feet but at KITH/KBGM/KAVP, MVFR/Alternate required conditions will persist until 21Z. This evening skies will be primarily clear except for a some scattered lake clouds at KSYR/KITH/KBGM. High pressure on Friday will give the area clear skies. Fog is not expected overnight due to dry air advection and boundary layer mixing. Northwest winds 8-12 knots with gusts 15-20 knots decreasing early this evening to 5 knots or less. Northwest winds on Friday at 7-10 knots. Outlook... Friday night through Saturday...VFR. Saturday night through Sunday...Showers/rain with MVFR/IFR restrictions. Monday...Primarily VFR. Tuesday...Showers with restrictions possible. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...None. NY...None. && $$ SYNOPSIS...TAC NEAR TERM...RRM/TAC SHORT TERM...JAB LONG TERM...JAB AVIATION...RRM