Area Forecast Discussion
Issued by NWS State College, PA

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KCTP 230427 AFDCTP Area Forecast Discussion National Weather Service State College PA 1227 AM EDT Wed Aug 23 2017 .SYNOPSIS...
-- Changed Discussion --
Much cooler and drier conditions will return for the second half of the week into the weekend. Temperatures will average a few degrees below normal highs starting tomorrow and lasting into early next week.
-- End Changed Discussion --
-- Changed Discussion --
Real FROPA has occurred at BFD. Dewpoints dropping nicely into the 50s behind it. Winds gusty as well. Line of showers currently moving over the radar is likely the first edge of the drier air, but the real show is 50 miles behind that. There are a few speckles along the real cold front, but mainly north of the NY border. Will continue to mention plain showers for the next 2-4 hours, but most will have dissipated by then with clearing to come to the NW. Despite the clearing, the winds and good dewpoint drop should keep fog away. Prev... The last of the potentially severe storms has cleared Lancaster county. Additional showers are moving east along ther Maryland border and there is also a line of showers moving through the northern mountains. The main windshift line associated with the cold front is just now entering NW PA. The RAP analysis shows the frontal trough jumping out to the east over central PA. The front will continue to accelerate through the area overnight ushering in markedly drier air by morning. POPs will taper off rapidly after midnight as drier air moves in behind the front. Some areas of fog are possible late at night as skies beging to scatter out.
-- End Changed Discussion --
&& .SHORT TERM /9 AM THIS MORNING THROUGH 6 PM THURSDAY/... Wednesday will be noticeably drier as the PW values crash to -1 sigma below normal after being well +1 to +2 sigma above normal. It will also be significantly cooler. The 850 hPa temperatures fall to near normal Wednesday and will fall below normal overnight Wednesday into Thursday. Chance of rain should be very low Wednesday. The cool air aloft will likely produce some cumulus in the mountains during the afternoon hours. It should be a nice and notably cooler day. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... An extended period of early autumn-like weather will begin Wednesday and continue right through the upcoming weekend as a -2 sigma upper trough (and similarly anomalous/cool 850 mb temps) move over the Great Lakes and NE U.S. 1026-1028 mb SFC High (+2-3 Sigma) over south-central Canada will drift slowly to the Great Lakes by this weekend Daytime high temps will be about 5-7 Deg F below normal across the Western Mtns on Wednesday, though still just slightly below normal across the SE zones prior to the arrival of the deeper/colder air for the latter part of the week. GEFS mean 850 mb temps will dip about 2-3 deg C in all locations for Thursday-Sunday, leading to max temps averaging 5-10 F below normal (with min temp departures about 10-13F below normal Friday-Sunday) as a large Canadian High Pressure area pushes SE across the Glakes Region and becomes centered over the NE states. Lows Fri/Sat/Sun mornings with high centered overhead will be dipping into the l-m 40s over the Northern Mountains (and deeper valleys of the Central Mountains) and solidly into the 50s elsewhere. Some of the perennial cold spots near and to the east of KBFD could see readings of 38 or 39F. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... Most of the eastern areas mostly sunny with some cumulus clouds about making for a bumpy ride in the boundary layer. Over western PA and OH there is a line of strong and severe storms. Strong winds and large hail are possible. Check radar before flying over western PA this afternoon and central areas this evening. The line of storms will move east this afternoon and evening. Areas of patchy fog will develop around/after midnight. Spotty MVFR and IFR. Conditions will improve rapidly Wednesday morning, as cool Canadian high pressure builds into the area. .OUTLOOK... Wed...AM low cigs BFD/JST, otherwise VFR. Thu-Sat...No sig wx expected. && .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...La Corte NEAR TERM...Dangelo/La Corte SHORT TERM...Grumm LONG TERM...La Corte/Lambert AVIATION...Grumm/Lambert is the U.S. government's official web portal to all federal, state and local government web resources and services.