


Area Forecast Discussion
Issued by NWS State College, PA
Issued by NWS State College, PA
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401 FXUS61 KCTP 171921 AFDCTP Area Forecast Discussion National Weather Service State College PA 321 PM EDT Fri Oct 17 2025 .SYNOPSIS... * Increasing clouds with light rain showers or sprinkles tonight into early Saturday morning over north central PA * Clouds break for p.m. sun with noticeably milder temperatures to start the weekend * The weekend ends wet/windy with gusty rain showers Sunday afternoon-Sunday night; trending breezy/cooler into Monday && .NEAR TERM /THROUGH TONIGHT/... Mid and high clouds continue spill south-southeastward this evening into tonight around an upper level ridge migrating eastward from the Great Lakes. A leading shot of low to mid level warm advection/uvvel (ahead of the sfc warm front) will trigger some light rain showers or sprinkles across north central PA tonight into early Saturday morning. Low temps will be +5 to +15 degrees higher than last night in the upper 30s to lower 40s. && .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... Sfc ridge axis migrates slowly eastward and reaches eastern PA by 12Z Saturday. 500mb ridge axis shifts to the east on Saturday with milder air surging into the area behind an broad southwest flow aloft. Early day clouds and leftover spotty light rain showers or sprinkles will fade as they shift/exit to the east toward the Poconos. Expect cloud breaks by the afternoon with increasing southerly flow helping to boost max temps +7-15F higher vs. Friday into the 60-70F range (+10-15F above climo along the Allegheny Plateau and Laurel Highlands). On balance, a mainly dry and milder start to the weekend. Amplifying 500mb trough will take on a negative tilt as it lifts through the Great Lakes/Ohio Valley into the Northeast on Sunday. A deepening a surface low (sub-1000mb) associated with the upper trough will track through Michigan into eastern Canada toward James Bay. Strong southerly flow ahead of the low will transport Gulf moisture northward and support a modestly moist air mass into PA. A cold front trailing the seasonably strong sfc low is expected to sweep eastward and serve as a focus for one or more lines/bands of gusty rain showers (shallow convective frontal rain bands) Sunday afternoon through the first part of Sunday night. The setup is a common transition season low CAPE/high shear environment with potential for strong to locally damaging wind gusts along the convective lines/frontal bands. Periods of heavy rain are also possible, but given the progressive forward motion, we feel that that flooding risk is pretty low or on the nuisance side (drought conditions also a contributing factor). Primary risk would be in urban or residential areas particularly where leaves clog storm drains. A tight pressure gradient and 3-6mb fall/rise couplet indicates gusty winds will continue behind the cold front as the llvl flow turns to the west. We adjusted NBM wind gusts higher to max out in the 30-40 mph range or below wind advisory criteria for now. This will be the first "windy" period this Fall with the potential to blow leaves and unsecured objects (Halloween decorations) around. Max temps top-out in the 65-75F range in most areas on Sunday with some locations possibly approaching 80F in the LSV. Expect a steady drop in temps across the western Alleghenies Sunday night with low temps -10F colder vs. Saturday night. && .LONG TERM /MONDAY THROUGH FRIDAY/... Breezy and cooler to start next week with rain showers exiting the area Monday night. Wind gusts in the 25-35 mph range are forecast during the day on Monday and will amplify the 24hr cool down/maxT change of -10 to -20 degrees vs. Sunday. After a brief dry period Monday night into Tuesday, the remainder of next week looks unsettled and quite showery (especially downwind of Lake Erie over NW PA and the western Alleghenies) under the influence of large scale upper level troughing and broad cyclonic flow. It`s conceivable that the the first flakes of the season may be found over the higher elevations along the Allegheny Front. I guess it`s that time of year... && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... A shield of high cirrus crossing the Great Lakes will continue to move over the region through the rest of today and overnight. Surface winds that have been gusty this afternoon will diminish and become calm during the early evening hours tonight, just after 00Z. The cloud deck will continue to build in from west to east, and ultimately an overcast deck near 10,000ft AGL is anticipated over much of the region by sunrise tomorrow. However, there is high confidence (>90%) in no restrictions to flight categories due to the increasing clouds. VFR conditions should prevail throughout this TAF package. The only area that could see some concern would be over northwestern PA near BFD. Scattered rain will likely develop off the coast of Lake Erie late tonight, and a PROB30 group has been included with BFD`s TAF to reflect the isolated chance of rain over that airfield. Outlook... Sat...VFR. A few showers possible over northwest PA. Sun-Mon...Restrictions possible in SHRA. Low probability of a thunderstorm over northwest PA. Tue...Lingering showers. && .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Steinbugl NEAR TERM...Steinbugl SHORT TERM...Steinbugl LONG TERM...Steinbugl AVIATION...Bowen