Area Forecast Discussion
Issued by NWS State College, PA

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816 FXUS61 KCTP 202250 AFDCTP Area Forecast Discussion National Weather Service State College PA 650 PM EDT Mon May 20 2024 .SYNOPSIS... It will feel like summer through midweek as a ridge of high pressure at the surface and aloft maintains warm and mainly dry conditions and light winds. A storm system moving north of the Great Lakes will push its southward trailing cold front through the region Wednesday night and Thursday bringing the next chance of showers and thunderstorms. Dry weather returns for most of the area to start this Holiday weekend, but wet weather could return late Sunday and Monday. && .NEAR TERM /THROUGH TUESDAY/... A summerlike day is in progress across Central PA with plenty of sunshine filtered by some high thin smoke plumes from Alberta Wildfires. Very shallow cumulus sprouting on the ridges and most of these will remain benign, but an axis of CAPE likely exceeding 1000 J/KG may locally be released over the higher northern and western terrain, and have left POPs around 20-25pct range late this aftn and early eve for this. Tonight will be similar to the last few nights, with perhaps less of a recurrence of the nighttime stratus. Valley fog is probable again tonight and will maintain the mention of patchy fog. Min temps early Tuesday in the upper 50s to around 60 will likely be a bit milder than Mon AM as well . && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... Temperatures warm each day through Wednesday afternoon, with this summer-like stretch of warm and mainly dry weather continuing through Wednesday afternoon. Periphery of upper level ridging/ring of fire type pattern reaches central PA late Wednesday with enough moisture for a more widespread chance of diurnally driven shower/tstorm activity Wednesday evening. Still, most areas will remain dry through 00z Thursday and it appears any organized activity will hold off until after dark. SPC has painted a MRGL outlook for 2 of my northwest Counties for this potentiality, with general T elsewhere. More widespread shower chances arrive late Wednesday night and Thursday as cold front slowly sags across the region. Best chance of widespread measurable rainfall comes Thursday with this setup. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... Temperatures remain on the warm side through the end of this week as the cold front to come through on Thursday and then stall out just south of PA on Friday. This will mean that the chance for scattered showers and t-storms will remain in the forecast for southern PA on the back side of that surface front. High temperatures will remain in the mid 70s as we move through Friday and into the weekend. There is considerable uncertainty heading into the weekend with regards to rain chances, but it appears that there is a chc that our weather could remain unsettled. PoPs have been capped at around 40 given the disagreement between model guidance for the likelihood of showers and storms. The best looking day for little rain is currently Sunday with upper level ridging building in ahead of the next system. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/...
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Isolated showers/tstms will develop across northwest part of the airspace through about 21/02Z. Should be short lived but have included VCTS in BFD TAF for the next 2 hours. Elsewhere, generally VFR conditions are expected through the evening. VFR prevails overnight and into Tuesday with patchy fog and low cloud impacts possible again during the predawn and early morning hours Tuesday. Outlook... Tue...VFR/no sig wx. Wed-Thu...Chance of t-storms. Fri-Sat...Mainly VFR, slight chance of showers.
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&& .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Lambert/DeVoir NEAR TERM...Lambert/DeVoir/Evanego SHORT TERM...Lambert/DeVoir/Dangelo/Evanego LONG TERM...Evanego/Bowen AVIATION...Gartner/Bowen