Area Forecast Discussion
Issued by NWS Pittsburgh, PA
Issued by NWS Pittsburgh, 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
097 FXUS61 KPBZ 231718 AFDPBZ Area Forecast Discussion National Weather Service Pittsburgh PA 118 PM EDT Mon Sep 23 2024 .SYNOPSIS... An active weather pattern is expected through most of the week. Even with the clouds and threat of rain, temperatures will remain warm through the week. && .NEAR TERM /THROUGH TONIGHT/... KEY MESSAGES: - Scattered showers along a passing cold front this afternoon. - Dry period likely for most of the overnight. ------------------------------------------------------------------- In the wake of the morning warm front passage, we`ve sat briefly in the warm sector ahead of an approaching cold front that will slowly progress eastward through the region this afternoon. Most of the deep moisture and best upper level support will be ahead of the front, and satellite observations don`t indicate much in the way of breaks in the clouds, so little atmospheric recovery will be possible ahead of the cold front. With fumes of instability to work with (hi res ensemble mean ~500-600 J/kg), won`t entirely rule out a rumble of thunder, but this should largely take on a widely scattered showers nature at most; additional accumulation will be light with the highest chance for >0.10" in the ridges. Behind the front, drier mid-level air works in and we should mostly lose the precip chances with for most of the overnight, save the higher elevations where upslope flow with lingering low-level moisture may provide some drizzle. Some areas of fog and low stratus are also on the table, especially where rain fell today, with sufficient low-level saturation. With the cloud coverage and elevated dew points, lows will fall to the low to mid 60s, some 10 degrees above normal. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY/... KEY MESSAGES: - Rain chances continue through mid-week. - Temperatures remain warm. ------------------------------------------------------------------- Height falls are expected on Tuesday as another shortwave trough swings through the region during the afternoon. This wave looks to be stronger than today`s and with southwest flow aloft, ahead of an upper low that will dig into the midwest, gulf moisture will stream in over the region. Another round of showers and possibly thunderstorms is expected Tuesday. Temperatures Tuesday will be above normal again. Little change on Wednesday as a large trough settles in over the Midwest. The area will remain on the eastern side of the upper level system, meaning gulf moisture will continue streaming northward over the region. Upper level waves will swing through the trough and eject northeastward in the southwest flow aloft. This will mean the threat for showers and possibly storms will continue through Wednesday. Temperatures Wednesday remain above normal. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... KEY MESSAGES: - Uncertainty increases greatly for the latter half of the week with potential tropical low interaction. - Rain chances will continue through the end of the week. ------------------------------------------------------------------- A weak boundary may pass through the area sometime Thursday, but seeing significant spread in the ensembles on the timing which will impact when we lose the rain chances. The central CONUS trough digs deeper on Thursday and looks to cut off from a northern stream trough, but ensemble clusters exhibit quite a bit of disagreement here. A faster solution cuts off rain chances overnight Wednesday night while others suggest a slower progression and maintain the rain all the way through Thursday night. Meanwhile, the remnants of a potential tropical system in the Gulf may interact with the trough. The highest probability scenario is that the northern stream trough is through by late week. A few ensembles still lag the passage, with some higher QPF totals possible across the southeastern half of the forecast area. Another cluster of ensembles has the system moving into the Midwest behind the trough. Will stick with NBM given all of the uncertainty. && .AVIATION /17Z MONDAY THROUGH FRIDAY/... A slow moving cold front is currently situated just west of ZZV. A number of sites have already fallen to IFR/MVFR/LIFR with passing rain from our overnight disturbance. However, with rainfall rates weak over the last 12 hours and dry air noted in the PIT 00Z sounding with lingering across the region, creating VFR conditions noted in some spots despite the rain showers. Cigs are expected to bounce between VFR/MVFR/IFR between 14Z to 18Z as warm air returns from the southwest with incoming disturbance over Missouri. Cigs are forecast to lift to VFR after 18Z, save DUJ and FKL, but coverage is expected to remain broken. Ample low moisture and reinforced saturation tomorrow night likely means another night of at least MVFR restrictions are ahead for most ports. More rain arrives Tuesday. .Outlook... Rain and restriction chance continues into Tuesday with another low pressure center. Unsettled weather is then possible through mid-week. && .PBZ WATCHES/WARNINGS/ADVISORIES... PA...None. OH...None. WV...None. && $$ SYNOPSIS...22 NEAR TERM...MLB SHORT TERM...22 LONG TERM...MLB/Milcarek AVIATION...Hefferan/Milcarek