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. --
851 FXUS61 KCTP 230729 AFDCTP Area Forecast Discussion National Weather Service State College PA 329 AM EDT TUE AUG 23 2016 .SYNOPSIS... Fair and pleasant weather continues today before turning warmer and more humid through mid week. The most likely opportunity for rain will be Thursday or early Friday. The upcoming weekend looks seasonably warm and mainly dry. && .NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
Calm winds and clear skies under high pressure will allow early morning temperatures to radiate nicely and bottom out in the mid 40s-50s range across most of central PA. 07z IR satellite loop is now showing some valley fog primarily in the Allegheny River basin which should expand toward daybreak. Aside from the fog early this morning, expect another pleasantly sunny and comfortable (low humidity) day with afternoon highs reaching the mid 70s to low 80s. High pressure remains in control through tonight with lows a bit warmer than the previous 2 nights but still relatively comfortable in the low 50s- 60s.
-- End Changed Discussion --
&& .SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
-- Changed Discussion --
High pressure shifts eastward midweek with a warmer and more humid south/southwest airflow returning deep moisture /1-2" PW/ to the Keystone State by the end of the period. This will favor increasing odds for rain across the NW Alleghenies where model consensus supports some light showers/QPF ending 25/12z. This area is in closer proximity to lead shortwave ejecting NEWD embedded in SW flow aloft and best low-level moisture flux/850mb LLJ in advance of surface cold front pushing toward the Lower Great Lakes. Max/min temps should climb a solid 5 degrees across the board.
-- End Changed Discussion --
&& .LONG TERM /THURSDAY THROUGH MONDAY/...
-- Changed Discussion --
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 on Thursday/D3. Anomalous PWs will almost certainly support localized heavy downpours and could also see WPC highlighting a MRGL risk area for excessive rain across NW PA. 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.
-- End Changed Discussion --
&& .AVIATION /07Z TUESDAY THROUGH SATURDAY/... Clear skies and a nearly calm wind expected overnight across Central Pennsylvania, as high pressure builds over the state. Radiational cooling, combined with warm river/stream water, should result in some early morning fog, mainly in the deep valleys north of I-80. Climatology suggests KBFD is the most likely airfield to be affected with IFR/LIFR conds. However, there is also some potential of briefly reduced vsbys at KAOO/KUNV/KIPT btwn 09Z-12Z. Any fog should burn off by arnd or shortly after 12Z, with a high confidence of widespread VFR conds and light wind the rest of the day. Outlook... Wed...Patchy AM fog possible, esp KBFD/KIPT. 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...Steinbugl NEAR TERM...Steinbugl SHORT TERM...Steinbugl LONG TERM...Steinbugl AVIATION...Fitzgerald/Gartner

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.