959 FXUS63 KPAH 191908 AFDPAHArea Forecast Discussion National Weather Service Paducah KY 208 PM CDT Fri Sep 19 2025
.KEY MESSAGES...
-Above normal temperatures to start off the weekend turn more seasonable by early next week, trending below normal in the latter half of the week.
-Daily rain chances will begin to increase in coverage Sunday into Monday, with heavy rainfall more probable through the middle of the week. Total rainfall between 1 to 3 inches is possible by next Thursday.
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.DISCUSSION... Issued at 207 PM CDT Fri Sep 19 2025
PVA associated with a shortwave trough over the the central Plains will provide subtle lift for an axis of isolated showers and storms this afternoon and evening. Although storms will remain very localized, heavy downpours, lightning, and brief gusty winds will be the main concern due to steep low-level lapse rates of 8.0 to 9.0 C/km and MLCAPE between 500 to 1500 J/kg. Pcpn chances turn even more sporadic on Saturday before increasing Sunday into Monday due to an influx of moisture transport from the southwest.
As a 500 mb cutoff low develops by the middle of the week near the Ohio Valley, a weak sfc low pressure will develop in the vicinity of the FA, pulling in even more moisture from the Gulf. The synoptic setup will set the stage for much needed rainfall between Sunday and Thursday. The 12z GEFS and EPS are in much better agreement, supporting at least 1 to 2 inches of total rainfall by the latter half of the week. In fact, both model ensembles now support a 70 to 90% probability of exceeding 1 inch of rainfall and 40 to 60% for exceeding 2 inches. The deterministic ECMWF and CMC remain the most robust with locally 3 to 4 inches, while the GFS continues to trend towards the wetter scenario.
Due to the long duration, any flooding issues should remain confined to vulnerable low-lying and poor drainage locations. While the overall flood risk is marginal, the risk for runoff on roadways will be greater given the hard soil conditions combined with PWATs between 1.50 to 1.75 inches. As the aformentioned closed low slowly pushes east Thursday into Friday, heavy rainfall will begin to taper, but lingering showers still are progged by the NBM due to persistent cyclonic flow on the backside.
Overall, increasing confidence in a wetter pattern next week will yield more cloud cover that will support a significant cool down. Temperatures that will be about 5 degrees above normal to start off the weekend in the mid 80s to near 90 trend more seasonable into the low 80s by early next week. In fact, temperatures 5 degrees below normal are now progged by the NBM in the upper 70s next Thursday as the 500 mb cutoff low causes 850 mb temps to cool down to near 10C.
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.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/... Issued at 1140 AM CDT Fri Sep 19 2025
The main concern this afternoon will be isolated thunderstorms near KCGI/KPAH/KMVN. Coverage will not be great, but any storms that develop will be capable of causing MVFR vsby reductions and gusty winds. Mid to high level clouds prevail into the overnight with a stray shower not ruled out, especially along I-64. Clouds scatter out Saturday morning with light & variable winds turning south around 4-6 kts.
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.PAH WATCHES/WARNINGS/ADVISORIES... IL...None. MO...None. IN...None. KY...None.
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DISCUSSION...DW AVIATION...DW
NWS PAH Office Area Forecast Discussion