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 170132 AFDCTP Area Forecast Discussion National Weather Service State College PA 832 PM EST Mon Jan 16 2017 .SYNOPSIS... A warm frontal system will approach the region tonight and Tuesday, followed by a cold front Tuesday night and early Wednesday. High pressure will follow and bring mainly dry conditions with temperatures several degrees above normal from the middle of the week into the weekend. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... MRMS RALA showing just a few spotty showers falling across central Pa at 00Z associated with developing WAA east of storm system over the Miss Valley. Watching surface obs closely and do see a couple 32F mesonet readings at 00Z across the Laurels/south central Mtns. With another batch of showers approaching, may need to issue a SPS for this area to cover possible icy spots. Based on upstream obs expect precip remain very spotty/light through at least 06Z, then steadier precip slated to overspread the region from the west late tonight, as shortwave and associated low level jet arrive. All latest model guidance suggests the main freezing rain threat will be over the higher terrain of northern Pa, with a diminishing risk in the valleys and over southern Pa. Will therefore make no changes to current freezing rain advisory, but will monitor temps across southern areas for a possible expansion. QPF will be light so amounts of ice are not expected to be significant, but as we have seen several times in the past few weeks, even a little ice on untreated surfaces can cause significant problems. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/... A steady rain will continue Tuesday morning, as the strongest WAA accompanies passage of low level jet. SREF and NAM both indicate the possibility of lingering icing through mid morning across the high terrain of northeast Pa. The mid level shortwave and associated low level jet are progged to shift east of the area between 18Z-21Z, causing rain to taper to spotty drizzle. Surface warm front is progged to push into the Laurel Highlands during the afternoon, pushing temps into the 50s down there. Elsewhere, readings expected to top out in the 40s most places and the upper 30s over the Mtns north of Williamsport. I kept POPs near 100 pct Tuesday based on latest GEFS/SREF probs and overall favorable pattern of anomalous PWATS and strong lg scale forcing ahead of shortwave. Blend of model QPF ranging fairly close to a third of an inch tonight/Tuesday. && .LONG TERM /TUESDAY NIGHT THROUGH MONDAY/... Winds turn westerly behind the system by Wednesday morning as flow turns more zonal, but with no real cold air in sight, temps will remain on the mild side and above freezing during the day. Ridge re-establishes itself over the eastern U.S. for late in the week, as mild SW flow persists over the midwest. Guidance suggests energy will dive south along the west coast eventually helping to strengthen the building upper ridge over the east. We`ll be on the eastern side of this, so subtle shortwaves sliding into the Midwest will bring varying amounts of cloudiness to the west (less in the east) with low end chances for light showers. Another wave approaches/lifts into the OH valley late next weekend into next Monday. Again, temps could be marginal at the start of pcpn overnight Sunday for some ice or snow, but the bulk of pcpn looks to be rain at this point. && .AVIATION /02Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
A few patches of light rain so far. Still close to freezing in spots, and the ground is cold, so freezing rain will be possible overnight. Also dewpoint still on the low side, which will result in temperatures falling off more in some spots. Freezing rain will be most likely on untreated surfaces, and on cold objects. Expect a wide range of conditions into Tuesday. JST already down to 1/4SM in dense fog, with a CIG of VV002. Rain will be more widespread on Tuesday, as the cold front moves toward the area. 00Z TAFS sent. Outlook... Wed...MVFR/IFR west; MVFR central to VFR southeast. Rain showers west ending Wed ngt. Thu-Fri...No sig wx. Sat...Sub-VFR developing with the approach of a warm front.
-- End Changed Discussion --
&& .CTP WATCHES/WARNINGS/ADVISORIES... Freezing Rain Advisory from midnight tonight to 10 AM EST Tuesday for PAZ004>006-010>012-017>019-037-041-042-045-046- 049>053-058. && $$ SYNOPSIS...La Corte NEAR TERM...Fitzgerald SHORT TERM...Fitzgerald/La Corte LONG TERM...Lambert/Gartner AVIATION...Martin is the U.S. government's official web portal to all federal, state and local government web resources and services.