Area Forecast Discussion
Issued by NWS State College, PA

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000 FXUS61 KCTP 231936 AFDCTP Area Forecast Discussion National Weather Service State College PA 336 PM EDT TUE AUG 23 2016 .SYNOPSIS... We should remain on the northern edge of the large subtropical ridge over the southeastern United States and on the southern edge of the westerlies for the next week. Weak fronts should push through our area as they try to move over the ridge. Ahead of each front there will be some minor surges in moisture. After each front high pressure will drift by. Bottom line relatively dry and comfortable late summer pattern for the next week or so. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... Big Bubble no trouble. Nudged grids to new guidance and put the HRRRV2 which is now the operational HRRR on top of this for some hourly texture. Fantastic day ideal temperatures and humidity. Get out there and ENJOY. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... Updated through 0000 UTC Thursday...just nudged the forecast grids for all fields. Retreating high pressure should lock in another fine day with some rebounding temperatures and some rebounding humidity as the day goes on. But still quite comfortable. Overnight Wed from previous: The GEFS seems to think any rain/showers would be in extreme western Pennsylvania overnight Wednesday but the probability is quite slow low east of McKean County. Most areas will be rain free. POPS generally below 10 percent Wednesday night except chance POPS in the two northeastern most counties. GEFS and SREF have low-end QPF bias and our blends are clearly too wet. && .LONG TERM /THURSDAY THROUGH TUESDAY/... No changes to previous forecast in store for this package. However, extended models do back off slightly on precipitation coverage for Thursday but slight to chance PoPs are still expected. Model data shows another glancing blow from passing shortwave energy/height falls to the NW of the area on Thursday as upper ridge holds firm from the Mid South up along the Atlantic coast. However, there appears to be sufficient moisture/instability with the weakening cold front/surface trough to trigger scattered to numerous thunderstorms during afternoon/evening. Consensus blend yielded max POPs over the NW 1/3 of the CWA. The front should become rather diffuse on Friday with risk of thunderstorms confined along/ahead of the boundary. The best location at this time appears to be the southeast 1/3 of the CWA and therefore painted low POPs during the day before drying things out Friday night. Forecast CAPE/shear profiles support MRGL risk outlook from SPC into far western PA on Thursday/D3, with room to expand and/or possibly increase level in later outlooks. Anomalous PWs will support localized heavy downpours. Another extensive upper ridge resumes control of the weather pattern into the weekend. This should translate into a seasonably warm and somewhat muggy period although not anything like the 70+ dewpoints we experienced around mid-month. The models seem to open the door for isolated airmass/terrain-induced convection by Sunday afternoon, however the odds still favor a mainly dry weekend for most locations. For next week, the guidance is suggesting a shortwave tracking to the north of PA will drag a trailing frontal boundary into PA which may become quasi-stationary Mon-Tue. This feature would provide a focus for thunderstorm activity and have generally trended POPs upward beyond Sunday. && .AVIATION /20Z TUESDAY THROUGH SUNDAY/... As noted earlier...VFR light winds. Great day to fly. Patch valley fog overnight. Could make locally MVFR and patchy areas in near water IFR. Clears out fast Wednesday morning. Another light wind kind of day. Outlook... Wed...Patchy AM fog possible. Thu...Isold pm tsra impacts possible, mainly w mtns. Fri...AM low cigs possible w mtns. Sat...No sig wx expected. && .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Grumm NEAR TERM...Grumm SHORT TERM...Grumm LONG TERM...Steinbugl/Tyburski AVIATION...Grumm is the U.S. government's official web portal to all federal, state and local government web resources and services.