Area Forecast Discussion
Issued by NWS State College, PA

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000 FXUS61 KCTP 201928 AFDCTP Area Forecast Discussion National Weather Service State College PA 328 PM EDT Sun Oct 20 2019 .SYNOPSIS... Rain will taper off from west to east late this afternoon, as low pressure (Post Tropical Cyclone Nestor) continues to move northeast along the Southeast U.S. coast. After some morning clouds and fog, a nice fall day is expected on Monday, with partly to mostly sunny skies and temperatures near normal. Low pressure tracking northeast across the upper Great Lakes will bring showers to the area on Tuesday. Dry weather returns for Wednesday and will likely last into the second half of the week. Near normal temperatures are forecast through late October. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... Rain will taper off from west to east late this afternoon and evening. Lower clouds have formed across the region, as the rain tapers off. Expect lower clouds to linger into Monday morning, along with some fog overnight. Low temperatures will be near normal for mid Oct. && .SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/... The extent of low clouds and rate of dissipation beneath inversion/high pressure ridge axis may impact maxT on Monday. I did edge temperatures up a degree or so, based on having a breeze form and a decent amount of warm advection. Still some question noted above to how fast the clouds and fog will burn off. Either way, a nice dry day for late Oct. && .LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
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Clouds will thicken Monday night, with confidence increasing on a band of rain moving west to east across the area on Tuesday. A wave of low pressure is progged to develop along the front near the Delmarva Tuesday evening, which should slow down the system`s eastward progression enough to continue rain over the far eastern zones into early Tuesday night. Model blend QPF results in widespread 0.50-1" soaking rainfall. It will turn mostly sunny and cooler for midweek, behind the departing system. Any light rain showers should be confined to the eastern Great Lakes through late week, based on the latest guidance. Models continue to disagree with the evolution of a system that should impact central PA late next week into next weekend. The 12z operational GFS and the 12z GEFS brings a cold front across the area Friday night, with low pressure developing along the front and sliding up the coastal plain of the southeastern U.S. This scenario would produce showers later Fri/Fri night and perhaps a period of steadier rain across SE PA. The 12z operational ECMWF, meanwhile, drags a weaker cold front and a few showers across the area Friday into Friday night, followed by a brief ridge of high pressure Saturday, before bringing a deeper area of low pressure up the Ohio Valley on Sunday. For now, leaned slightly towards the GFS/GEFS solution, but held a bit more cloudiness and low-end PoPs across the area into the weekend to account for continued uncertainty.
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&& .AVIATION /20Z SUNDAY THROUGH FRIDAY/... As noted in the 12Z TAF package, CIGS came down as the rain started to taper off. Expect more low clouds overnight, along with fog. Not a lot of change to the package. Main thing was how fast things improve on Monday. I am a little faster than some of the guidance. A return to wet conditions on Tuesday. Improving conditions after Tuesday, as weak high pressure builds into the region. .Outlook... Tue...Rain/low cigs possible. Wed and Thu...No sig wx expected. Fri...Some showers possible, especially west late. && .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Martin NEAR TERM...Martin SHORT TERM...Martin LONG TERM...Evanego AVIATION...Martin is the U.S. government's official web portal to all federal, state and local government web resources and services.