Area Forecast Discussion
Issued by NWS State College, PA

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000 FXUS61 KCTP 261150 AFDCTP Area Forecast Discussion National Weather Service State College PA 750 AM EDT Thu Apr 26 2018 .SYNOPSIS... High pressure will be here for a short time today. A series of troughs will then begin to cross the region over the weekend. Each shot of energy will knock the temperatures down a little, and give us a few rain showers. A stretch of fair weather with a warming trend will start Monday as high pressure builds over the Atlantic Coast. Above normal temperatures are likely for the middle of next week. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... Typical stratus covers 80pct of the area this morning. It might be tough to get rid of with to linger over the NW half of the area this morning as there seems to be no sign of the lowering inversion to our NW. Will keep on with the call that it should break up slowly from S-N and most of it slink away very late in the day and early this evening. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/... However...a fast moving wave over AR this morning which will become caught up in the SW flow just ahead of the longest- wavelength upper trough axis. The pressure dips only a mb or two as it treks up the lee side of the Apps late tonight and Friday. There will be a little moisture added into the system as it moves northward. So, a period of rain is likely for mainly the SE half/third of the area - centered on Fri morning. The chance for rain tapers off to the NW and POPs will not be noticeable for the far NW. However, 100 POPs on tap for the SErn third of the area. A broad area of lowered pressure and many sfc troughs will be left circulating over ONT and the NE CONUS. The deepening trough looks like it could cut off as it moves over the Lower Lakes in the middle of the weekend. So, while much of Fri night looks dry, the big trough axis generates an area of showers for Saturday which transits most of the area. Likely POPs are on tap for the nrn half of more of the area. Temps will still get into the 60s in the SE, but could hold in the 40s NW. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... A shot of arctic air is going to try to make it in Saturday night and Sunday with 8H temps near -10C and 1000-500 thickness less than 530dam. The consistency across the models is pretty good with this mass field result, so confidence in cold temps and a gusty NW wind is high. The lake/8H temp difference might be enough to generate SHSN at night/Sun AM. But, it warms up nicely on Sun. The crest/ridge axis of high pressure dropping down from central Canada will probably be on Mon. While temps will get cold Sat night - U20s NW to N40 SE - the worry for frost in the areas growing now is practically nil as wind stays up/gusty most of the night and clouds linger over the NW half and could bleed into the ridge and valley region. Freeze/frost will be more of a worry Sun night/Mon morning as the sky clears out and wind would go calm. Temps Mon morning could get into the 30s everywhere and upper 20s again in the northern valleys. But, the difference in wind and sky cover should lead to at least a frost if not freeze in some of the growing areas. The next chunk of counties (around AOO- UNV- IPT) does not go active for frost/freeze products until May 1st. The high pressure will continue to slide to the E and S and set up along or just off the Atlantic Seaboard for the middle of the week. Look for temperatures finally rising above average and real spring weather arriving next week with many areas finally seeing a substantial green-up. && .AVIATION /12Z THURSDAY THROUGH MONDAY/...
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Low level moisture ascending the the Appalachian Mountains will produce stratocu across much of western and central Pa early this morning, with the lowest (LIFR) cigs across the northwest mountains. However, mixing of drier air aloft will result in clearing skies by late morning. Model soundings and SREF prob charts support a near certainty of widespread VFR conditions for this afternoon. Low pressure lifting up the eastern seaboard will likely spread rain and lowering cigs into southern Pa around dawn Friday. Outlook... Fri...Rain/low cigs possible, mainly eastern Pa. Sat...AM fog possible. Sun...Breezy. AM low cigs/flurries possible W Mtns. Mon...No sig wx expected.
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&& .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Dangelo NEAR TERM...Dangelo SHORT TERM...Dangelo LONG TERM...Ross/Dangelo AVIATION...Fitzgerald

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