Area Forecast Discussion
Issued by NWS State College, PA

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857 FXUS61 KCTP 250130 AFDCTP Area Forecast Discussion National Weather Service State College PA 830 PM EST Fri Feb 24 2017 .SYNOPSIS... 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. && .NEAR TERM /UNTIL MIDNIGHT TONIGHT/... Unseasonably warm conditions for mid to late February with evening temps some 30+ degrees above normal. All-time February record highs set at both Williamsport (76F) and State College (PSU weather center - 74F). Balmy southerly wind will continue throughout the evening. && .SHORT TERM /MIDNIGHT THROUGH 6 PM SATURDAY/... 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 bizarre 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. && .LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/... The mid range models all have similar timing for FROPA. the front should be east of central PA by 00Z Saturday. Cold northwesterly flow could allow for snow showers Saturday night into Sunday. However lack of moisture will only bring light accumulations with the highest amounts in the NW mtns. After some morning flurries and scattered snow showers in the NW Sunday, the trough will continue its eastward trek and a more zonal pattern will overtake the region. This will bring more tranquil conditions with some sunshine expected for Sunday afternoon, along with decreasing winds. However, max temperatures on Sunday will be back to near normal. 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. The latest 12Z runs show a warm frontal boundary moving into the region Tuesday. This will bring the next chance for precipitation with possible warmer than normal temperatures though not as high as currently. Another upper level trough moving through the Great lakes could bring another cold front through the mid Atlantic region later next week. There are inconsistencies in timing and placement. && .AVIATION /01Z SATURDAY THROUGH WEDNESDAY/...
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Widespread VFR conditions noted across central Pa at 00Z, which will remain the case into the late evening hours. An increasingly moist south-southeast flow is expected to result in developing stratus across eastern Pa late tonight. Believe current LAMP guidance is a bit too pessimistic regarding CIGs late tonight. Although pattern favors IFR CIGs over the higher terrain of eastern Pa late tonight, not so sure about the lower elevation airfields, including KIPT, KMDT and KLNS. If IFR were to develop in those location, favor the idea of it taking until around dawn to occur, as the latest HRRR depicts. A strong cold front will sweep eastward across central Pa between 15Z-21Z, accompanied by a band of showers and possible thunderstorms. Model soundings continue to suggest the potential of borderline IFR CIGs across eastern Pa (mainly MDT/LNS) early in the day. However, by midday the focus will be on line of showers/tsra accompanying the front, as it pushes across the state. Brief IFR conditions are possible with this band of showers and possible tsra. A much drier westerly flow behind the front should result in a return to VFR conditions late in the day across most of central Pa, while MVFR CIGs linger at JST/BFD. Gusty west winds will become a concern in the wake of the front late Saturday, especially in the vicinity of JST/AOO, where Bufkit soundings support gusts between 30-35kts. Another concern will be developing lake effect snow showers Sat evening at JST/BFD, where tempo IFR visibilities appear possible. Outlook... Sun-Mon...No sig wx expected. Tue-Wed...Rain showers/reduced CIGS possible.
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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/DeVoir SHORT TERM...Dangelo LONG TERM...Ceru/Gartner AVIATION...Fitzgerald CLIMATE...

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