Area Forecast Discussion
Issued by NWS Paducah, KY
Issued by NWS Paducah, KY
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
851 FXUS63 KPAH 212338 AFDPAH Area Forecast Discussion National Weather Service Paducah KY 638 PM CDT Tue May 21 2024 .KEY MESSAGES... - Heat continues today with highs in the upper 80s to lower 90s. Breezy today as well. - Storms possible later this evening through the overnight. Some could be strong to severe. - Storms possible again tomorrow afternoon through evening. Some could be strong to severe. - Storms look to be possible each day through Sunday. Sunday looks to be the best chance for severe weather. Will need to watch Sunday closely. && .DISCUSSION... Issued at 235 PM CDT Tue May 21 2024 Aloft there is an upper low over Alberta/Saskatchewan with a trof through MT and WY. A leading shortwave is moving through the northern Plains and upper Midwest. The sfc low is intensifying and moving through eastern NE, IA, and MN with an attendant cold front running southwest to northeast. Good southerly flow at the sfc today is helping to advect in higher dewpoints in the upper 60s and highs in the upper 80s to lower 90s. Convection looks to initiate late this afternoon along the cold front/dry line to the west over central and southwestern MO and moves through towards our area this evening. The cold front is then expected to stall to our north and west this evening. Some of the anticipated storms this evening could be strong to severe. Severe parameters look decent with 0-6 km shear 30-40 kts, 1,500-2,000 J/kg of MUCAPE, and mid level lapse rates around 7.5-8 degC/km. The main threats would be wind and hail with a low tornado risk. Tomorrow the first upper level low moves north of MN with an embedded shortwave moving through the upper Midwest in the afternoon. Models mostly show a break in convection tomorrow morning (with the exception of the EC). Storms tomorrow afternoon/evening will be very contingent on there being this break during the morning. More daytime heating will yield more instability. If storms can take off (and several models suggest they do) then several could become severe, though convection looks to be short lived and only last through the evening. Models are showing 2,500-3,500 J/kg of MUCAPE, 45-50 kts of 0-6 km shear, and mid level lapse rates of 6.5-7.5 degC/km. All modes of severe look to be possible with supercells being the primary cause, though coverage looks to be isolated to scattered. PWATs also look to be in the 90th percentile both tonight and tomorrow. A Flood Watch may not be necessary though due to the isolated nature and brief duration of the the storms. However, localized flash flooding is still possible with heavier downpours. There is still a little bit of discrepancy between the EC and the GFS with regards to precip on Thursday. The EC has more widespread rain vs the GFS. The cold front which had stalled north and west of the area, looks to maybe sag south slightly and then kind of wash out over the area during the day. In the current pattern both models show precip chances each day through Sunday. A few storms could be strong to severe each day, but it`s hard to say for sure at the moment. Sunday a more organized shortwave aloft comes out of the central Plains. There is good consistency in the EC and GFS with the presence and progression of this shortwave. The severe threat on Sunday looks to be stronger than tonight or tomorrow. 0-6 km shear is 40-60 kts, MUCAPE is 2,500-3,500 J/kg, and mid level lapse rates are an impressive 8.5-9.0 degC/km. This is still quite a ways away though and will bear close watching. && .AVIATION /00Z TAFS THROUGH 00Z THURSDAY/... Issued at 631 PM CDT Tue May 21 2024 There are two periods of convection that may impact the terminals. The first is ongoing to the west, with a line of SHRA/TSRA. This activity is expected to push into SEMO, and portions of S IL overnight with a weakening trend. Reductions in ceilings and visibility is likely near any shower activity or thunderstorms. The highest confidence for tonight is at CGI and MVN. Guidance favors MVFR CIGS by sunrise for most sites with some IFR possible at CGI. The next period of SHRA/TSRA arrives Wednesday afternoon. Gusty south winds will continue for a few more hours this evening before relaxing to 5-10 knots for the remainder of the period. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...None. MO...None. IN...None. KY...None. && $$ DISCUSSION...SHAWKEY AVIATION...AD