790 FXUS61 KBGM 200535 AFDBGM Area Forecast Discussion National Weather Service Binghamton NY 135 AM EDT Sun Oct 20 2019 .SYNOPSIS... Tropical remnants will skirt the region today and bring scattered showers to Northeast PA and the Catskills region. High pressure will return Sunday night and Monday with mainly clear skies. && .NEAR TERM /THROUGH TODAY/... 620 PM update... Made very small changes to the forecast, mainly with hourly temperatures. Latest guidance suggests temperatures quickly fall off to the mid 30s to lower 40s before midnight tonight before leveling off the remainder of the night as clouds increase across the area. That being said, overall low temperatures remain very similar to the previous forecast. Rest of the forecast remains unchanged. Previous Discussion... High pressure over the area now will exit to the east the rest of today. With the dry low level air, frost and valley fog are possible again late tonight. With more clouds and stronger boundary layer winds fog will be less than this morning. Low temperatures will also be warmer from the mid 30s to around 40. High clouds are already moving into the far south from the southwest. This is well ahead of the tropical remnants of Nestor over the Florida panhandle. Light rain is now moving into Virginia on its way northeast. More models now have some light rain moving into northeast PA and the Catskills during the day Sunday. Rain amounts may get to a tenth of an inch in the Poconos. Clouds are expected across the entire CWA but most of the clouds from the central southern tier to the western Mohawk Valley will be mid and high clouds. High temperatures will be warmest there in the upper 60s and lower 50s. For northeast PA and the Catskills highs will be in the mid and upper 50s. Late Sunday rain and clouds will start exiting to the east. Skies become partly cloudy. Weak high pressure moves in late. Valley fog will be possible again. Winds go light to calm. Temperatures fall to around 40 for most of the area. && .SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/... Monday... Our region will be situated between Post-Tropical Cyclone Nestor (moving farther off the southern Mid- Atlantic coast) and low pressure over the Upper Midwest. The ridge axis associated with surface high pressure will shift to our east through the day as height/pressure falls spread eastward ahead of the Midwest low. The day should be dry but high clouds could start to overspread the area late. A warm southerly flow ahead of the upstream trough will yield a mild autumn day with highs in the mid to upper 60s (5-10 F above normal). Monday night... Deep southerly flow in the pre-frontal warm sector ahead of the Great Lakes cutter will continue to become established over the area. The leading edge of rain showers is forecast to approach from the west late. PoPs increase from west to east overnight though there are still some timing differences among the latest guidance wrt the onset of precip. Tuesday and Tuesday night... The latest guidance has the low lifting to the north-northeast across western Ontario and toward Hudson Bay. The setup could provide a period of moderate to perhaps locally heavy rainfall ahead of the front as a 50-kt southerly low-level jet and plume of anomalously high PWAT air (over +2 SD) arrives. Differences among the models in timing/speed of the cold front are notable, leading to some uncertainty regarding when the heaviest rain falls and exactly how much falls. A more progressive solution (e.g., 12Z GFS) would favor the heaviest rain occurring from the late morning thru mid afternoon but with lighter storm total amounts (QPF 0.5-1"). Conversely, a slower, more amplified solution would delay the heavier/steadier rains until late in the afternoon or Tuesday night. The heavy rain threat would be greater in the latter scenario with some of the slower, wetter guidance advertising localized QPF amounts exceeding 1.5" (as indicated by the 90th percentile values from the latest NBM v3.2). Given the low will likely become cutoff and how amplified the downstream flow becomes, a slower solution seems a bit more plausible. Although we should be able to handle the runoff without much issue based off QPF amounts from the current deterministic forecast, the wetter envelope of models support low probabilities for localized/minor flooding in poor drainage areas. Accordingly, we will continue to monitor the flooding threat over the coming days. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... A deep upper trough moves into the area Tuesday through Tuesday night. A strong surface low tracks northeast from the midwest through the western Great Lakes into northern Ontario. An occluded front will move through our area with showers/ periods of rain Tuesday and Tuesday night. Models have slowed a few more hours but not as much as previous days. Ahead of this front and lifting upper level trough will be a deep southwest flow of moisture from the Gulf of Mexico. Precipitable water is expected to be over one inch and be 2 to 3 standard deviations above normal. With the jet support this could be another 0.50 to 1.5 inch rain event. With the rain this week, the flood potential will need to be watched. With that said, the latest guidance seems to be coming in just a touch lower with rainfall amounts, as there really is no southern wave along the front this time around. Highs near average and around 60 Tuesday. A broad but not deep upper level trough will be over the area Wednesday. A westerly flow of cool air will create lake enhanced rain showers across our northern counties east of Lakes Erie and Ontario. Cooler with highs in the 50s and lows mid 30s to mid 40s. Significant model differences are then evident by the end of the week and into the early weekend. Used a blend of the latest guidance which favors generally dry weather Thursday/Thursday night with a chance of rain possibly arriving later Friday and into the weekend. Forecast confidence is lower than average Friday and Saturday as guidance is out of phase with potential systems moving through. Temperatures are looking seasonable, with highs in the mid-50s to low 60s and overnight lows in the mid-30s to low 40s. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... Light IFR fog is forecast to develop between 09z and 13z at KELM early Sunday morning. Southerly winds of 20-30 knots off the deck should preclude LIFR fog, but we will continue to monitor the situation. VFR conditions are forecast across our terminals today and tonight, except at KAVP, where tropical remnants will cause MVFR restrictions in showers during the late morning and early afternoon hours. Winds will be light through Monday morning. Outlook... Monday...mainly VFR. Monday morning valley fog possible at ELM again. Monday night through Wednesday...restrictions possible in showers. Thursday...mainly VFR. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...None. NY...None. && $$ SYNOPSIS...DJP NEAR TERM...BJG/TAC SHORT TERM...JRK LONG TERM...JRK/MJM AVIATION...DJP