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
38
39
071 FXUS63 KPAH 282310 AFDPAH Area Forecast Discussion National Weather Service Paducah KY 610 PM CDT Fri Jun 28 2024 .KEY MESSAGES... - Trend is for higher dewpoints and more uncertain convective coverage Saturday. Heat Advisory issued for part of the area. - A front will bring the next chance of showers and storms on Saturday. The greatest risk looks to be Saturday evening into Saturday night when isolated strong to severe storms will be possible. Damaging winds, small hail, torrential downpours, and lightning are the main concern. - Brief relief from the heat and humidity is in store Sunday into Monday before turning uncomfortable again in time for the 4th of July. The pattern also turns unsettled by the middle of the week. && .UPDATE... Issued at 606 PM CDT Fri Jun 28 2024 Updated Aviation discussion for 00Z TAF Issuance. && .DISCUSSION... Issued at 212 PM CDT Fri Jun 28 2024 Dewpoints are rising on modest south winds this afternoon. We are already back into the low 70s across much of the area. With the moisture advection we are seeing some mid level clouds that coupled with MCS blowoff are providing some respite from the heat. Very rich lower column and surface moisture sits just to our south and is expected to make its way overhead by Saturday afternoon. Despite this moisture flux, poor 700-800mb lapse rates/an inversion from residual subsidence will set out convective temperature in the upper 90s which leads me to believe home grown convection will be hard to produce. There is a fairly consistent signal for an MCS to develop across central MO and IL tonight which may impact areas north of Rte 13 and parts of far northwest KY and SWIN. The expectation for now is that at least enough residual cloud cover from this activity will keep temperatures just cool enough to not quite reach advisory threshold there. To the south heat index values of 105-110 seem reasonably likely in the afternoon hours so a Heat Advisory has been issued with this forecast package. Saturday afternoon and into the evening large scale ascent increases in response to a mid/upper level shortwave. This should initiate storms to our northwest that will then work to the east and southeast. There will be plenty of potential instability, with MLCAPE values 2000-2500 J/kg in the late afternoon but a residual inversion around 850 mb may limit coverage unless cold pools can upscale and organize. This may be somewhat challenging given the fairly modest deep and mid level shear and fairly moist column overall. PWAT values are projected to be 2.2-2.4" with wet bulb zero heights over 14,000 ft. This looks like a recipe for robust updrafts that struggle to organize, but if a few do they may briefly become capable of damaging wind. Its going to take quite an effort to produce much hail however given the freezing levels and weak deep layer shear. Rainfall rates will be very efficient and some isolated flooding may also come into play with storm motions likely to be fairly slow in weak westerly shear. A "cooler than it was" front then moves through Sunday morning. We get another brief respite from the highest heat and humidity through Sunday and Monday with Monday really looking pretty pleasant. Not to get too spoiled we get back into the humidity Tuesday afternoon with a day that looks pretty similar to today. The deeper moisture return then gets to work with a stronger and broader upper trough to create an unsettled pattern that looks to lead to showers and storms through the holiday before another front possibly moves in for the weekend. Shear and instability may come together for some type of wind/severe threat the 3rd through 5th but there is no real screaming signal. There will have to be a pretty big shift however to avoid at least some disruption to July 4th outdoor activities. && .AVIATION /00Z TAFS THROUGH 00Z SATURDAY/... Issued at 606 PM CDT Fri Jun 28 2024 A cold front will be approaching the flight terminals over the next 24 hours. Showers/storms along it will blow off mid and high level bases that will offer SCT-BKN VFR bases at our terminals tonight. As the front gets closer tmrw, it spreads its chances of pcpn in as well, with lower bases and potential restrictions to VSBYS in thunderstorms, mainly during the heating hours tmrw. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...Heat Advisory from noon to 7 PM CDT Saturday for ILZ084-085- 088>090-092>094. MO...Heat Advisory from noon to 7 PM CDT Saturday for MOZ076-086- 087-100-107>112-114. IN...None. KY...Heat Advisory from noon to 7 PM CDT Saturday for KYZ001>013- 017-022. && $$