Area Forecast Discussion
Issued by NWS State College, PA
Issued by NWS State College, PA
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145 FXUS61 KCTP 060556 AFDCTP Area Forecast Discussion National Weather Service State College PA 156 AM EDT Thu Jun 6 2024 .SYNOPSIS... A warm front extending from Eastern Lake Erie to the Greater Philadelphia Area will lift slowly northeast overnight, followed by a cold front pushing east through Western and Central Pennsylvania on Thursday. It will turn breezy and less humid behind the front on Thursday with near to slightly above normal high temperatures. Friday and Saturday will be cooler and less humid with diurnal showers that will be most numerous across Northern PA. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... Surface warm front extended from near KERI to KUNV and KLNS this evening with the axis of steadiest and heaviest rain over the past 6-8 hours being located near this boundary`s current position. SFC cold front was slicing through the NW half of Ohio attm and will push into the Western Mtns of PA during the early to mid morning hours Thursday and the Central Mtns during the late morning/early afternoon. A relative mid in POPS with only isolated to scattered showers will be found across our Central Zones and Susq Valley between 04Z and 12Z. The far eastern zones seeing a likelihood of lingering showers and TSRA, linked to the nose of the Swrly LLJ (ahead of a compact mid/upper level shortwave) riding up and over the aforementioned warm frontal boundary and causing highly efficient showers of varying intensity. Compensating subsidence in the wake of this meso-B feature and veering, westerly flow aloft will lead to will mean little additional QPF overnight over much of the Central third or so of the CWA and less than 0.75 of an inch in the east as instantaneous precip rates are below 0.25 of an inch across the bulk of the region. Scattered showers/TSRA will move back into the western zones late tonight, along and ahead of the cfront. PWATS hovering between 1.5 and 2 inches over the entire CWA will lead to a muggy /warm night with temps ranging through the 60s, to near 70F in the SE metro areas. Sfc dewpoint will only be a few deg F lower. The threat for any poor drainage and small stream flooding issues will be steadily decreasing overnight across Central PA and the Susq Valley. && .SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY NIGHT/... Primary cold front will be moving into the Central Mtns later Thu morning/midday hours with PWAT values dropping to between 0.8-1.0 inch for much of the afternoon, prior to the much drier air pushing in Thur night with PWATS under 0.7 of an inch. Left <50 PoPs in the east during the morning. Additional convection is expected, esp in the W) in the aftn as a secondary cfront moves through and the upper cold pool nears. Thurs night stabilization should diminish/kill most of the precip, but some fog is possible as we cool off to near dewpoints. Maxes Thursday will be similar to today, but humidity should get down to about 50pct for most of the CWA, much less humid. Friday should be more typical of a late-spring day under an upper low. A channel of higher vorticity rolling across the area should make numerous SHRA/TSRA. The showers should spread from NW to SE thru the day/aftn, but might not get into the Lower Susq. Maxes Fri should be much below normal with m60s in the NWrn Alleghenies and nearer to normal with u70s over the SE. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... Reloading of the mean Glakes/NE U.S. upper trough by a few shortwave troughs dropping Southeast will maintain the chc for mainly diurnal showers/isolated to sctd TSRA through much of the extended period. Current indications are that by the end of the weekend into early next week, the upper tough becomes positively tilted and the low may retrograde slightly and stall over the Great Lakes region, especially considering the additional energy helping to deepen the trough. This will continue the unsettled pattern of diurnally driven showers and thunderstorms through at least Monday afternoon. Long range ensembles currently show the trough lifting after Tuesday morning with lower pops for showers/TSRA as we head into the middle of next week. Temperatures are likely to average somewhat below climatology for early to mid-June, with daily highs in the upper 60s and 70s, and overnight lows in the 50s to lower 60s. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... MVFR ceilings will prevail across much of the area through daybreak, with IFR cigs likely over the higher elevations, especially over Northern PA. Patchy valley fog is likely as a result of showers during the day today, with <2 mile visibility already reported at AOO. A complex of showers and storms is moving into western PA at 2AM and may bring heavy rain to JST/AOO/UNV between 07 and 10Z. This complex may help improve visibility at AOO for a bit as the showers move through. Showers should weaken with eastward extent overnight as restrictions persist. Improving flying conditions are anticipated late Thursday morning, as a trailing cold front comes through followed by the arrival of a drier southwest flow. Model RH profiles support predominantly VFR conditions Thursday afternoon and evening. However, a few thunderstorms could form on the cold front as it crosses the Lower Susq Valley early Thu afternoon, bringing the chance of a brief vis reduction in vicinity of KMDT/KLNS. Also, latest HREF indicates a brief shower/vis reduction will remain possible across the Allegheny Plateau (KBFD/KJST) through early evening. Outlook... ...Slight chance of a brief PM shower/vis reduction, mainly NW Mtns. Sat-Mon...AM low cigs possible NW Mtns. Slight chance of PM shower/vis reduction NW Mtns. && .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Lambert/Steinbugl NEAR TERM...Lambert/Dangelo SHORT TERM...Lambert/Dangelo LONG TERM...Lambert/Fitzgerald/Bowen AVIATION...Banghoff/Tyburski