952 FXUS61 KBGM 201015 AFDBGM Area Forecast Discussion National Weather Service Binghamton NY 615 AM EDT Mon Apr 20 2020 .SYNOPSIS... High pressure will build in today bringing dry but cool weather to the region. A cold front will pass through on Tuesday bringing showers and isolated thunderstorms. Some of the storms over eastern New York and northeast Pennsylvania could contain strong winds. && .NEAR TERM /THROUGH TUESDAY/... A weak surface high will drift across the area today bringing drier air, and light winds. It will be cooler today, but air is not all that cold and the strong mid April sun will make for a pleasant day as highs reach into upper 40s to lower 50s. Weather story in the near term is for Tuesday as a cold front pushes through. There is some weak instability ahead of the front, especially east of I-81, that could potentially tap stronger winds that are zipping along just above the boundary layer. SPC has put the area in a marginal risk with the primary risk damaging wind gusts if that low level jet can be tapped. In any case the front is pretty much through the area by 21Z. Models differ in the weather behind the front with the NAM bone dry, while the Regi and GFS show lake enhanced showers breaking out almost immediately in the cold advection. Have gone with a compromise between the two for now, but suspect it will take sometime for the showers to develop since the air is cold, just not that cold and it should take the lake a while to react. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... 410 AM Update... Generally busy unsettled pattern continues, though there will also be a brief break with high pressure midday Wednesday through Wednesday evening. Strong cold air advection will reach its apex Tuesday night as upper trough swings through the area. Fairly gusty west- northwest winds will persist Tuesday night into Wednesday with the strong pressure gradient between the departing front and incoming high pressure. 850mb temperatures drop to 10-13C below freezing; enough touch off a minor lake response and thus lake effect snow showers/flurries Tuesday night through early Wednesday. A few flurries could even briefly cross the NY-PA border. That said, air mass will be very dry with dewpoints in the upper teens-lower 20s Tuesday night; then dipping even more Wednesday into mid teens as mixing occurs with increasing sun. That will also continue to mix down winds 15-20 mph gusting 25-35 mph. So all told, in terms of lake effect, any accumulations will be nominal. Light skiffs to about an inch possible, especially higher terrain of Onondaga-Cortland- Chenango-Madison counties. Regardless it will be subject to quick sublimation Tuesday night and melting early Wednesday. After lows in the 20s Tuesday night, highs Wednesday are anticipated to be upper 30s-upper 40s. Weak high pressure ridge passes Wednesday evening, only to be overtaken by warm air advection of zonal flow later Wednesday night and pivoting southwesterly into Thursday ahead of a trough. Initial embedded shortwaves will work to thicken cloud cover Wednesday night-early Thursday. If there is enough moisture, perhaps even a chance of mixed snow-rain may occur before becoming an increasing chance of rain showers during the day Thursday. There is a fair amount of uncertainty for where and if moisture will be adequate for precipitation; it will have to overcome dry air in the low levels. Highs Thursday will be upper 40s-upper 50s. && .LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/... 415 AM Update... We cannot seem to catch a break from continued frequent disturbances and below average temperatures. Though the pattern is unsettled, there is also a lot of model spread in timing and location for expected wave passages. The jet stream may split into separate branches for a time late in the week, and the southern stream will attempt to send us a wave Thursday night into Friday. The question is, how far north its influence will extend. Models generally agree on showers reaching the MidAtlantic area including Northeast Pennsylvania, but some including the ECMWF have too much dry air for precipitation to reach north of the Twin Tiers. Either way we are looking at cloudy and cool weather, with at least some chance of rain north and likelihood of it south. Window appears to be closing between that first wave, and the next series of them over the weekend. At this point model consensus points to Friday night into early Saturday being mainly dry, yet flow pivots west-southwest with embedded shortwaves. We get back into an upper trough-dominant pattern as time carries forward; and with that, chances for precipitation return later Saturday through Sunday night. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... VFR conditions will prevail through the TAF period under high pressure. A front approaching for Tuesday may result in LLWS at some stations near the end of the TAF period. Outlook... Tuesday...Restrictions possible in rain showers and thunderstorms. Wednesday and Thursday...Mainly VFR. Friday...Restrictions possible in rain showers. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...None. NY...None. && $$ SYNOPSIS...DGM NEAR TERM...DGM/MWG SHORT TERM...MDP LONG TERM...MDP AVIATION...DGM/TAC