Area Forecast Discussion
Issued by NWS State College, PA

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594 FXUS61 KCTP 020801 AFDCTP Area Forecast Discussion National Weather Service State College PA 401 AM EDT Sat Nov 2 2024 .SYNOPSIS...
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*Seasonably cooler and dry first weekend of November #Fallback *Warm Autumn pattern resumes next week with near-record high temperatures possible Tuesday (Election Day) and Wednesday *Limited rain chances Wednesday-Thursday with below average precipitation likely into mid November
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&& .NEAR TERM /THROUGH TONIGHT/...
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Recent IR satellite trends in the last hour (07-08Z) indicate the stubborn stratocu starting to break across CPA early this morning. The slowly eroding cloud cover and persistent NW breeze will hold temps in the upper 30s to upper 40s to start the first weekend of November. Increasing large scale subsidence/downward motion associated with 1030mb high pressure migrating eastward from lower MI will result in a continuation of the decreasing cloud trend (gradual clearing) through late morning with plenty of sunshine expected by the afternoon. Seasonably cooler day on balance with max temps in the 50-60F range; 15-20 degrees lower vs. Friday throughout the Susquehanna Valley. Not as breezy as yesterday which should help to reduce the wildfire spread risk to some extent despite continued low humidity (minRH 30-50%) and 1-10hr forecast fine/dead fuel moisture 10-20%. Clear and frosty overnight with min temps in the 25-35F range. Manually adjusted lows below baseline NBM via blend of the 10-25th percentile and traditional MOS data given favorable radiational cooling pattern under anomalous sfc high and pwat values <0.4 inches.
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&& .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
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Sfc ridging extending down the eastside of the Appalachians on Sunday gets replaced by an increasingly milder southerly return flow through early next week. This pattern will maintain dry weather Sunday and allow temperatures to trend warmer day/day with highs rebounding to +5 to +15 degrees above the historical average for early November by Monday (55-65F). Minimum temps follow a similar trend making a series of higher-lows and rising 10 to 20 degrees above climo by Monday night (45-50F). The abnormally dry conditions and continued lack of wetting rainfall will perpetuate a higher than average wildfire risk into next week. Model data indicates increasing wind/gusts from the south on Monday should be offset by an uptick in low level moisture (dewpoints/RH), but examination of soundings suggests there is some potential downside which could result in a 10-15% reduction in minRH.
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&& .LONG TERM /TUESDAY THROUGH FRIDAY/... 11 PM Update: Ensembles now keeping precip off to our north early in the period. So, we`ll remove the small PoPs from the NW. Otherwise, the front may be a tiny bit slower than current, but 80 PoPs are OK for the NW before sunrise Wed. Prev... With the sfc high moving offshore Mon night, S to SW return flow on Tuesday should help dewpoints increase into the 50s (+10 deg from Mon). With the upper level ridge axis directly overhead, Tue will likely be the warmest day of the week for much of central PA, with highs again making a run into the 70s for much of the area (15-25 deg above avg). A cold front will slowly approach from the west, bringing with it a 50-70 pct chc of showers across western zones later Tue night into the day Wed. As has been typical with frontal passages lately, most model guidance shows precip waning as the front pushes into southeast zones. Wed looks like another very warm day in the south and east with temps in the mid 70s, but clouds and precip in the NW will hold temps to the mid 60s. Temps will be on a downward trend but still look to be 5-15F above avg in the Thu-Fri timeframe. Not much rain is expected behind the front, but due to timing differences with the frontal passage, slgt chc - chc PoPs are carried for much of Thu-Fri. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... At 06z, a deck of stratocu persists over much of central PA and continues to slowly build southward. Cigs are generally MVFR over the western highlands (BFD/JST), borderline MVFR/VFR over the Ridge and Valley region (AOO/UNV/IPT), with 4-5 kft cigs building southward into the Lower Susq Valley (MDT/LNS). Expect similar conds to persist through the overnight, with a light NWerly breeze of 5-10 kts. The stratocu deck should gradually erode from south to north this morning, with conds becoming VFR areawide by afternoon. A light NWerly breeze (5-10 kts) will persist through the day. Outlook... Sun...Patchy AM valley fog across the north; otherwise VFR w/ no sig wx. Mon...Predominantly VFR, with a southerly breeze developing; patchy -RA is possible across the far north. Tue...Widespread VFR, with a southerly breeze continuing. Tue night-Wed...Restrictions possible with rain showers developing. && .FIRE WEATHER...
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Low humidity and fuel moisture conditions will continue through the weekend with no rainfall expected. However, decreasing/light winds associated with high pressure moving into the Keystone State will reduce wildfire spread risk on balance. We will continue to coordinate with fire partners regarding the issuance of elevated wildfire spread risk/SPS.
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&& .CLIMATE...
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October 2024 ended as one of the driest on record for much of Central PA, particularly across the southeastern part of the Keystone State. The following list outlines the driest Octobers on record in Harrisburg: 1. 1924 0.02" 2. 1963 0.04" 3. 1930 0.11" 4. 1892 0.15" T5. 2024 0.47" T5. 2000 0.47" Harrisburg Dry Spell: MDT measured 0.01 inch of rain Friday morning, ending the number of consecutive days with no measurable rainfall at 24. This ties 1922 (09-13 to 10-06) as the 8th longest dry spell.
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&& .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Steinbugl NEAR TERM...Steinbugl SHORT TERM...Steinbugl LONG TERM...Dangelo/Colbert AVIATION...Evanego FIRE WEATHER...Steinbugl CLIMATE...Steinbugl