248 FXUS61 KPBZ 101925 AFDPBZ Area Forecast Discussion National Weather Service Pittsburgh PA 325 PM EDT Wed Oct 10 2018 .SYNOPSIS... Rain showers will move through the region Wednesday night through much of Thursday. Afterward, a cold front will bring much cooler air into the region. && .NEAR TERM /THROUGH TONIGHT/... Showers associated with a weak shortwave ahead of an approaching cold front currently (as of 19z) extended from the Mason-Dixon line into northwest Ohio. These showers will move through much of the region in the remainder of the afternoon and evening hours. Lack of instability will preclude general thunderstorm development, but cannot rule out an isolated rumble of thunder or two. && .SHORT TERM /THURSDAY THROUGH FRIDAY/... Models are in good agreement with the cold front moving across the Allegheny Plateau and general area Thursday morning. Low level warm air advection may steepen lapse rates just enough such that a couple thunderstorms are possible, but general coverage will be low enough that I chose not to include in the gridded forecast package. With such a warm cloud layer and PWATs running >1.50" (>90th percentile), the strongest convection will be quite efficient rain producers. However, quick storm motion will limit any flood threat. Expect rain totals from near an inch in the ridges to around a half inch elsewhere. Temperatures will remain stable or even cool a bit in the afternoon as the cooler air filters into the region behind the front. A few isolated showers will remain possible along the higher elevations and along the I80 corridor Thursday evening as northwest flow fetches moisture off the lakes. Friday will be cool and cloudy with temps topping out in the 50s as a cool northwest flow continues and a stratoCu field develops off the warm lakes. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... By this weekend, upper level longwave troughing becomes more established across the eastern CONUS. A robust shortwave will move through Friday night into Saturday, bringing the next chance of rain showers. Forecast soundings show temperature profiles just a bit too warm in the low levels and too dry in the dendritic snow growth region for snow showers... but just a small change in the forecast and the atmosphere may be conducive for some flakes mixed in with rain in the higher elevations or across the northern portions of the CWA (I80 corridor). Temperatures will remain a bit below normal over the weekend and through much of the week with highs generally in the 50s (near 60 on Sunday) and lows ranging from the mid 30s to 40s. Another strong trough will bring another chance of rain showers Monday night into Tuesday morning. Like before, forecast soundings are slightly too warm for snow, but something that will definitely need to be watched in the coming days. && .AVIATION /19Z WEDNESDAY THROUGH MONDAY/... VFR is expected through the afternoon under a high pressure ridge. A few showers are possible late this aftn as the ridge shifts E, and a weak shortwave in SW flow crosses the area. Widespread deterioration to MVFR and eventually IFR is expected tonight into Thursday morning with the approach of a cold front. Ceilings will eventually begin to scatter out and lift to VFR Thursday afternoon. Outlook... Restrictions are possible Thu night through Sat with cool NW flow and upper troughing, and again Sun with a crossing cold front. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...None. OH...None. PA...None. WV...None. && $$