Area Forecast Discussion
Issued by NWS State College, PA

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627 FXUS61 KCTP 241837 AFDCTP Area Forecast Discussion National Weather Service State College PA 137 PM EST Fri Feb 24 2017 .SYNOPSIS...
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A strong cold front will plow east across the region on Saturday and create showers and perhaps a narrow line of strong, gusty thunderstorms. Gusty westerly winds and colder temperatures will follow the frontal passage. Some snow showers are also expected late Saturday and Sunday in the western highlands. High pressure builds in from the Ohio Valley for Sunday but weak waves of low pressure will move up the Ohio River Valley Monday into Tuesday may bring some mixed precipitation to the northern half of the area, and mainly rain in the south.
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&& .NEAR TERM /UNTIL MIDNIGHT TONIGHT/...
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Temps on track and crazy high for late Feb. See Climate section for more. Southerly wind will continue all evening, but should be weakening after sunset.
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&& .SHORT TERM /MIDNIGHT THROUGH 6 PM SATURDAY/...
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Takeaways: CFROPA expected around 12Z W and 18Z E. SHRA/TSRA along and behind the front. Some will be strong/gusty. Severe not out of the question, but risk still only MRGL in newest DY2 outlook from SPC. Gusty post-front but not wind advy-worthy. Overnight: The SSE flow up into the mountains will lead to low clouds and they may get thick enough to produce some drizzle or even very light showers overnight. The faster the clouds thicken up, the warmer it will stay overnight. Will run with mins in the 50s. (Yes, it just seems plain bizzare writing that in late Feb.) The clouds will also make it tough to destabilize during the morning - esp in the NE where the --precip may be lingering into the first part of the day. The front will push across steadily and only taking about 6 hours to cross the entire CWA. POPs will be pegged at 100s. Temps will drop very quickly and should be back into the L-M30s in the NW by the end of the aftn. SHRA will turn to SHSN there in the aftn. Winds will be gusting into the 30s with some peaks in the 40s behind the front. But, at this point, it does not look like a wind advy is necessary.
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&& .LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
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Snow showers in the westerly flow will not last long Sat night and Sunday. After some morning flurries and scattered snow showers Sunday, more tranquil conditions with some sunshine area expected for Sunday afternoon, along with decreasing wind and gusts. Heights are forecast to rebuild across the eastern half of the conus early next week on broad southwesterly flow ahead of troffing developing over the Rockies. Several shortwaves within the fast southwest flow aloft will bring several weak fronts across the region next week. This will lead to less than pristine sky conditions...but most of the time period will be generally dry. However, enough low pressure lurking at the surface could lead to a system of more significance sometime during the week.
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&& .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
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VFR for more than the first half of the 18Z TAFs in most while the southerly flow moistens things up. Late this evening or early in the night the southerly flow will make low clouds over the area - thickest/lowest in the NE. There might be some drizzle or very light showers there overnight due to the upslope and increasing moisture. Will drop most locations to MVFR in the middle to end of the night. Then the cold front will be the main focus of precip. Just a few showers are expected along or ahead of the front, with much of it along or even behind the front. But, it should pass through quickly. Timing of onset of TS/SHRA will be around 12Z in the western terminals and before 18Z in the east. Gusty winds are possible in any TSRA, and post-frontal winds w3ill line up nicely as well. LLWS will be likely with srly 925mb winds up to 35KTS and stable llvls in the east. LLWS possible W but it may just remain gusty/mixed all night. Directional shear behind the front would limit snow showers. Highest chance for snow showers would be BFD, as the cold air will be a little deeper there. r concern will come after midnight, when radiational cooling leads to areas of low CIGS/fog. Outlook... Sun...Windy. SHSN W in AM. Mon...Light mixed precip poss/reduced CIGs/VIS. Tue...Widespread SHRA/reduced CIGS possible. Wed...CFROPA. SHRA/TSRA pre-front. IFR likely and windy post- front.
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&& .CLIMATE... ***February Warmth 2017*** Updated 2/24/17 at 5 am EST Record high temperatures for select sites for Feb. 23-24: ---------------------------------------------------------- Harrisburg 2/24: 75 in 1985; all-time Feb record is 78F Williamsport 2/24: 71 in 1985; all-time Feb record is also 71F Altoona 2/24: 69 in 1985; all-time Feb record is 74F Bradford 2/24: 59 in 1961; all-time Feb record is 64F ----------------------------------------------------------- Most 60 degree days in February at Harrisburg. Based on the latest forecast, add 4 more days to the list and finish tied for second with 7 days. 1. 10 days in 1976 2. 7 days in 1930 3. 5 days in 1991, 1943 5. 4 days in 1997, 1985, 1954, 1939 9. 3 days in 2017, 2016, 1996, 1990, 1961, 1932, 1890 ------------------------------------------------------------ Warmest February on Record (Avg. Temperature through 2/21) Harrisburg: 2017 rank=4 (38.6) 1. 40.4 in 1998 2. 39.6 in 1976 3. 39.4 in 1954 Williamsport: 2017 rank=4 (35.4) 1. 37.0 in 1998 2. 36.1 in 1954 3. 35.6 in 2002 Altoona: 2017 rank=2 (36.5) 1. 37.4 in 1976 Evening cooling will be a little slower than last night. Bradford: 2017 rank=6 (29.3) 1. 32.3 in 1998 2. 30.1 in 2002 3. 29.6 in 2012 4. 29.5 in 1990/1976 ------------------------------------------------------------- && .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Dangelo/Lambert NEAR TERM...Dangelo SHORT TERM...Dangelo LONG TERM...Lambert/Gartner AVIATION...Dangelo CLIMATE...

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