Area Forecast Discussion
Issued by NWS State College, PA
Issued by NWS State College, PA
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
409 FXUS61 KCTP 181908 AFDCTP Area Forecast Discussion National Weather Service State College PA 308 PM EDT Wed Sep 18 2024 .SYNOPSIS... *Mostly cloudy tonight with pockets of light rain tapering off into Thursday *Little to no rainfall expected Friday into early next week perpetuating one of the driest September`s so far on record *Daytime temperatures peak +5-10 degrees above average Friday and Saturday before trending seasonably cooler next week && .NEAR TERM /THROUGH TONIGHT/... Precipitable water values have likely peaked across central PA this afternoon. Expect an increasingly drier mean flow from the north northeast to steadily lower deep layer moisture across the region which will correspond to decreasing rain probs (from north to south) and eventually cloud cover into Thursday. Lows tonight will be in the 55-65F range with some potential for radiational valley fog development into early Thursday morning particularly in the northern tier where pockets of clearing are most likely. && .SHORT TERM /THURSDAY THROUGH SATURDAY/... The aforementioned mean northerly flow will continue to dry things out into the weekend. However, a few bands of enhanced mid-level FGEN forcing to the northwest the slowly departing upper low/mean trough suggest holding on to a slight chance for rain near and to the east of the I-81 corridor through Friday night. Latest global guidance now suggest an isolated shower cannot be ruled out on Saturday as another piece of shortwave energy dives down the backside of the departing upper trough or down the frontside of upper ridge building into the Ohio Valley. On balance, expect a dry period for the majority of the area with variable clouds and daytime highs +5-10F above the historical average for mid/late September. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... Higher confidence in dry wx/no rainfall particularly early in the period (through the upcoming weekend) thanks to deep layer ridge pattern at the sfc and aloft. While model variability remains elevated into next week, the ensemble means generally favor weak upper troughing centered around the Great Lakes which will support a marginal increase in rainfall/shower potential along/ahead of an approaching front by next Monday or Tuesday. Forecast max temps 75-80F peak +5-10F above mid/late September climo to start the weekend and trend modestly cooler to 65-75F (near the historical average) into early next week. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... Pockets of light rain will gradually diminish over the southern half of the airspace through the evening. The highest confidence and max probability of MVFR/IFR cigs will be around KJST/KAOO prior to 19/00Z with VFR expected elsewhere across the airspace. Conditional risk of fog/vis restrictions overnight especially at KBFD/KIPT where skies may partially clear out. A much drier flow pattern will allow for trending/prevailing VFR conditions through the end of the week. Outlook... Thu...Trending VFR. Fri-Mon...Valley fog in the morning; otherwise VFR/no sig wx. && .CLIMATE... The first day of Autumn 2024 (Fall Equinox) begins at 8:44 am EDT on September 22nd. && .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Steinbugl NEAR TERM...Steinbugl SHORT TERM...Steinbugl LONG TERM...Fitzgerald/Steinbugl AVIATION...Steinbugl CLIMATE...NPB