351 FXUS61 KBGM 172234 AFDBGM AREA FORECAST DISCUSSION National Weather Service Binghamton NY 634 PM EDT Fri May 17 2019 .SYNOPSIS... A cold front will sweep through the area this afternoon bringing showers, followed by drier air. High pressure will build over the region Saturday with partly sunny skies. && .NEAR TERM /THROUGH SATURDAY NIGHT/... 630 PM Update...Only made minor changes to sky cover, rest of the forecast remains on-track. High pressure and drier air is quickly filtering in behind the cold front and clouds have pushed out a little faster than previous forecast. Still a few showers across the Pocono Mountain Region as the front exits. 3 pm update... Cold front now in the middle of the CWa with some showers with it in south central NY. As it shifts south into more humid air thunderstorms are possible for NEPA and the Catskills. Precip moves out early this evening so that by around 7 PM it has pushed southeast. Drier air is on the way behind the cold front, and has made it across Lake Ontario. This should move in tonight. Valley fog isn't likely with boundary layer winds stay up. Moisture above the boundary layer is low. Low temperatures will be in the low 40s in CNY and mid and upper 40s in NEPA/Sullivan County NY. A ridge of high pressure at the surface sets up late tonight then continues through Saturday. Aloft heights are rising with a ridge moving east. A warm front in Michigan and western PA Saturday morning tightens as it slowly pushes east into our area Saturday night. The front lifts northeast late Saturday night. A good trigger is missing but a few showers are possible. Removed the threat of thunderstorms. Model soundings not showing very much instability aloft. Saturday temperatures get to the 60s in the northeast to the low 70s for NEPA valleys. Coldest across the upper Susquehanna Region to the Tug where the northwest flow will be off of the cold waters of Lake Ontario. Low temperatures mostly in the low and mid 50s. Coldest again in the Catskills to the Tug. && .SHORT TERM /SUNDAY THROUGH MONDAY/... For Sunday, all four main synoptic models indicate that an upper level ridge axis will be moving just east of NY and PA as a southerly flow of warm and moist air engulf the region. The surface warm front is projected to be north of central NY so our entire forecast area of central NY and northeast PA will be in the warm sector of a large cyclone in the upper midwest. This cyclone is embedded within a southwesterly flow aloft with the upper level wave heading northeast during the day Sunday. This will lead to a cold front moving into the central Great lakes to western Ohio Valley by Sunday evening. As a result, there will be a strong low-level jet stream from the Tennessee valley northeast into the eastern Great Lakes as the pressure gradient tightens. The winds up to 850 mb will be south to southwesterly over all of NY and PA with dewpoints rising well into the 60s. Model soundings for NAM and GFS to a lesser extent show a capping inversion across many of our sites. The NAM fires some sort of MCS in PA with less convection in NY state. The GFS, 00Z Euro and CMC all have some sort of convection firing. CAPEs are projected to be up to or above 1000 J/KG in the mixed layer. The Bulk Shear from 0-1 km shear reaches between 20 and 30 knots and the deep layer shear between 0-6 km shear reaches 40-45 knots by late in the day. Forcing will be lacking for most of the day so not too confident in severe potential this far out. SPC day 3 has general thunder, so for now, we will not mention in HWO. It is possible that nothing fires until late in the day as it will all depend on how strong the capping inversion is vs. the low- level moisture/instability. Additionally, most of the day the forcing will be too far west ahead of the short wave and surface front. So for now, we have POPS for showers and thunderstorms increasing through the day with likely POPs late in the day from the upper Mohawk Valley to the Finger Lakes and chance POPs farther south and east into northeast PA. Then for Sunday night, forcing increases as short wave tracks from the upper Great Lakes to central/northern Quebec and pushes a cold front into western NY and far northwest PA by 12z Monday. CAPE will be waning with the loss of the day's heating but the shear and forcing will be increasing so we have chance POPS in northeast PA to Likely in central NY Sunday Night. Then for Monday, front crosses the region but main upper forcing will be well north of the region so POPs will be in the chance category with highest chance for thunderstorms in our eastern areas from the Upper Mohawk Valley to northeast PA where there will be lingering instability. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... For Monday night, there will be a sustained northwest flow of moist and chilly air with plenty of clouds and some light showers/sprinkles mainly from north central NY to the Catskills. For Tuesday and Tuesday night, high pressure dominates with fair weather. Next system affects the region from Wednesday into Friday with significant model disagreement as to timing and extent of precipitation associated with a short wave moving over the top of the building southeast upper level ridge. The Euro/GFS and CMC all have different timing of this wave and hence uncertainities abound this far out from Wednesday to Friday. So went with superblend for now and also blended with neighboring offices as to POPs and Max/Min temperatures. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... 130 pm update... Mainly VFR this afternoon through Saturday. A cold front is sweeping through the area now. Isolated showers are with and ahead of it. Showers and maybe a thunderstorms will become more widespread. The showers could bring brief restrictions to ITH/BGM/AVP and maybe ELM. This lasts to 20z in NY and 20 to 23z at AVP. Behind the front is drier air so the lower clouds will scatter out later today. Winds depend on the front. Southwest winds at 10 kts south of it at AVP to start. West at 10 with some gusts near it in south central NY and NW at 10 kts with some gusts north of the front at SYR/RME. Tonight at all sites NW winds drop to 5 kts and remain there Saturday. Outlook... Saturday through Sunday morning...Mainly VFR. Sunday afternoon through Monday...Restrictions possible in rain showers. Tuesday through Wednesday...VFR with high pressure. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...None. NY...None. && $$ SYNOPSIS...TAC NEAR TERM...MPK/TAC SHORT TERM...DJN LONG TERM...DJN AVIATION...TAC