159 FXUS61 KBUF 091037 AFDBUF Area Forecast Discussion National Weather Service Buffalo NY 637 AM EDT Wed Oct 9 2019 .SYNOPSIS... A large area of high pressure will remain in place across the Saint Lawrence Valley through the remainder of the work week, bringing our region dry conditions with light winds and comfortable autumn temperatures. A cold front will sweep across the Eastern Great Lakes region Saturday with rain showers likely. && .NEAR TERM /THROUGH TONIGHT/... High pressure will remain over the Saint Lawrence River Valley today and tonight, bringing dry weather and comfortable autumn temperatures to our region. Fog in the river valleys of the Southern Tier this morning will dissipate by mid-morning. After the fog dissipates mid-morning abundant sunshine will be found across western zones, while clouds filtering sunshine will pass over eastern zones. These clouds, associated with an upper level closed low rotating across Pennsylvania will thin through the day from west to east as the low advances farther eastward. With no change in the airmass, temperatures will be similar to yesterday, with highs in the 60s. Tonight will be a repeat weather-wise, with clear skies...fog filling the river valleys of the Southern Tier and Black River and temperatures dropping into the upper 30s to mid 40s with light winds. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... A narrow mid level ridge sandwiched between a low off the East Coast and a low moving into the Northern Plains, will build into the area and remain in place through the end of the week. This ridge will maintain dry weather with mainly sunny days and clear nights. There may be a little patchy nighttime fog at times in normally cooler valleys. Temperatures should be near or even a bit above normal with highs in the 60s, perhaps nearing 70F by Friday with overnight lows in the 40s. && .LONG TERM /SATURDAY THROUGH TUESDAY/... Rainshowers associated with a cold front tied to an occluding low pressure spinning over Minnesota will move east into western NY by Saturday afternoon. Meanwhile, the parent upper low over Minnesota will edge to east-northeast, which will begin to push a narrow upper ridge downstream to the east of our area by late Saturday. This will be the final straw that will end our prolonged stretch of dry weather across the Lower Great Lakes region. This boundary will push through the remainder of the area Saturday night, with showers ending from west to east by Sunday morning. Daytime highs will remain a little above average with temperatures maxing out in the 60s. Lows will fall back into the upper 30s and 40s Saturday night, as cooler air starts to build in behind the boundary. Surface high pressure centered over the Mid Atlantic states will ridge north across the Lower Great Lakes region Sunday into the start of the new work week keeping dry weather intact across western and north central NY through at least Monday. Temperatures will probably fall just shy of average with highs in the 50s as a cooler airmass briefly resides over us. Slightly warmer air will already be moving back over the area aloft Sunday night, as southerly return flow kicks in on the western periphery of the high as it pushes toward the east coast. Expect lows mainly in the 40s, with some upper 30s across the higher terrain. However, it will be a bit warmer on Monday with highs mainly in the lower 60s, with upper 50s reserved for the coolest spots. Model discrepancies exist toward the end of the period as to how much influence the large upper low oscillating about eastern Canada will have on our area. Meanwhile at the surface, a cold front will move toward the region, but may wash out just to the northwest of our area if the upper low stays on its' current forecast track, moving northeast across Hudson Bay. Will bring a slight chance for a few lake enhanced showers downwind of the lakes for Monday night, which will be possible if the colder solutions verifies. Otherwise, will bring a general low chance of showers in on Tuesday as the cold front to the northwest approaches the area. Low temperatures will be in the 40s Monday night, with highs in the upper 50s to lower 60s on Tuesday. && .AVIATION /12Z WEDNESDAY THROUGH SUNDAY/... For the 12Z TAFS VFR flight conditions are found, and these conditions are expected to continue through the TAF period with light winds as surface high pressure remains near the region. The exception will be valley fog in the Southern Tier tonight that may expand across KJHW late as winds at the top of the boundary layer diminishing earlier overnight allowing for some fog bank expansion. Outlook... Thursday through Friday...VFR. Saturday...VFR/MVFR with showers likely. Sunday...Mainly VFR && .MARINE... Surface high pressure will drift from the St Lawrence Valley to southern Quebec over the next 24-48 hours and winds will be east to northeast on the waters. Down the long fetch of Lake Erie, winds may near 15 knots around Dunkirk to Ripley late this afternoon and again on Thursday. Otherwise, light winds and waves are expected to continue through the end of the work week with high pressure nearby. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...None. MARINE...None. && $$ SYNOPSIS...Thomas NEAR TERM...Thomas SHORT TERM...TMA LONG TERM...JM AVIATION...Thomas MARINE...Thomas