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
691 FXUS63 KPAH 021636 AFDPAH Area Forecast Discussion National Weather Service Paducah KY 1136 AM CDT Tue Jul 2 2024 .KEY MESSAGES... - Dangerous heat and humidity levels are expected Wednesday and could develop over portions of the region on Thursday as well. - Scattered to numerous thunderstorms are forecast at times from late Tuesday night through Friday evening. Some of the storms could be severe Wednesday afternoon and evening. Heavy rain and isolated flash flooding will also be concerns. - Drier, less humid, and cooler weather is forecast for the weekend. - Daily chances of thunderstorms are forecast for the first half of next week, and temperatures will be near normal. && .UPDATE... Issued at 1135 AM CDT Tue Jul 2 2024 Updated Aviation discussion for the 18z TAF issuance. && .DISCUSSION... Issued at 247 AM CDT Tue Jul 2 2024 High pressure aloft is building over the Quad State early this morning, but according the 00Z guidance it will quickly be suppressed back to the south of the region by late tonight and Wednesday. The upper trough moving eastward across Ontario tonight and Wednesday is forecast to be a bit stronger with more energy farther south. This works on the ridge and allows convection to survive farther south as early as the pre-dawn hours tonight/Wednesday morning. The current thinking is that convection will make it into our northwest zones well after midnight tonight and then push over most of southeast Missouri, southern Illinois, and possibly southwest Indiana before dissipating by midday Wednesday. The residual outflow boundary or differential heating boundary will likely focus thunderstorm development Wednesday afternoon and evening. This development would be most likely over the northwest half of the area in the afternoon and then push eastward over the remainder of the area Wednesday night. The next upper storm system will be stronger and farther south. This will bring another round or two of thunderstorms through the area at some point Thursday into Friday. It is forecast to push a cold front eastward through the entire Quad State Friday, which will bring an end to the convective activity. Moderate to strong instability will be available across the region on Wednesday. Wind fields will not be totally pathetic, but will still struggle to organize convection. A few strong to severe storms with damaging winds will be possible throughout the region. Depending on how much heating occurs on Thursday, a severe storm or two could be possible again then. Precipitable water values will be around 2", which will support torrential rainfall. There is a chance that the main convective boundary will become oriented parallel to the zonal flow aloft leading to training potential. All in all, the chance of some portion of the area seeing some significant flash flooding seems to be increasing, especially Thursday into Friday, presumably after the area has already endured one round of heavy rainfall. For today through Friday, the GEFS and ECENS both indicate highly anomalous upper ridging and low-level moisture in our vicinity. However, after the cold front passes Friday, they indicate a near normal state of the atmosphere for the weekend into next week. The NBM is now indicating a dry weekend, but general troughing aloft will persist through the weekend and into next week. Eventually, more energy will drop into the trough and bring more chances of storms. NBM PoPs begin Sunday night and continue through next Tuesday, but they are 50% or less which seems reasonable given the situation. Temperatures today will climb up to near 90 throughout the region, but the humidity albeit increasing, will not be significantly disgusting to impact heat indices. However, humidity along the lines of last Saturday will return on Wednesday, with temperatures climbing toward the middle 90s. This bring heat indices to 105 or greater over most of the region. A Heat Advisory will likely be needed for Wednesday. Thursday certainly could be hot and humid again, but confidence is low given the expected convection. Beginning behind the front on Friday, temperatures will generally be within a degree or two of normal each day through next Tuesday. && .AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/... Issued at 1135 AM CDT Tue Jul 2 2024 High pressure will keep skies mostly clear through late tonight, with some passing high cirrus over EVV and OWB being the only clouds of note. Mid and high cloud coverage will increase towards daybreak Wednesday from ongoing storms to our NW. Steady S winds around 5-10 kts will veer slightly to the SSW after 14z Wednesday, sustained at 7-10 kts with gusts up to 15-20 kts possible at EVV and OWB. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...None. MO...None. IN...None. KY...None. && $$ UPDATE...DWS DISCUSSION...DRS AVIATION...DWS