433 FXUS63 KPAH 251959 AFDPAH Area Forecast Discussion National Weather Service Paducah KY 259 PM CDT Wed Sep 25 2019 .SHORT TERM...(Tonight through Friday morning) Issued at 256 PM CDT Wed Sep 25 2019 We are currently experiencing a lull in precipitation as a cold front approaches the region from the northwest. Ahead of this front, skies have cleared across southeast Missouri, while scattered to broken low/mid level clouds continue across much of the rest of the region. Diurnal heating has allowed MLCAPE values to reach 1000 to 1500 J/kg across our western four counties in SE MO. Colocated with this instability is 25-35 kts of effective bulk shear. This environment could support an isolated strong or severe thunderstorm...should one develop. Short range CAMs are not in agreement with coverage and placement of convection. Latest HRRR runs are quite bearish on anything more than isolated thunderstorms developing along the front late this afternoon into this evening. The better chances for precipitation would be early Thursday morning from a decaying MCS moving east from the Ozarks, but there is also model disagreement about whether this complex impacts our region or slides south of us. Felt NBM guidance was too bullish for POPs, so decided to go with a blend of persistence and CONSShort. This yielded high chance/low likely POPs at times for SE MO, W KY, and the southern tip of Illinois from late afternoon through tomorrow morning. By Thursday afternoon, the cold front and any lingering precipitation should clear the PAH CWA. Dry high pressure will shuffle in from the northwest, and it should be a pretty pleasant day all things considered. Quiet weather is expected through the remainder of the period. .LONG TERM...(Friday afternoon through Wednesday) Issued at 256 PM CDT Wed Sep 25 2019 There is pretty good agreement amongst the medium range models today. We will start out with southwest flow aloft and southerly winds at the surface on Friday. A storm system moving eastward across Ontario Friday will bring a cold front down to near the I-70 corridor to our north. The front is not expected to reach our region, nor will any associated convection/precipitation. As that storm system continues east northeast, the upper ridge over the southeast will build back across our region through the weekend. There may be just enough warm advection to produce a few showers or storms over the I-64 corridor Saturday night into Sunday morning, but by Sunday afternoon the upper high will become dominant and keep our region hot and dry through at least next Wednesday. Guidance indicates that there may be enough cloud cover on Saturday to hold down temperatures a few degrees, but otherwise, high temperatures will generally be in the lower 90s through the period. Normal highs for the beginning of October are in the upper 70s, so this will be quite extreme for this time of year. Record highs will be in jeopardy, especially Sunday and Monday, mainly at KCGI and KPAH. The humidity will be highest on Sunday and Monday and a few locations over southeast Missouri and the Purchase Area may approach triple digit heat indices each afternoon. There is some sign of relief coming in the form of a significant cold front just beyond this forecast period. && .AVIATION... Issued at 1225 PM CDT Wed Sep 25 2019 Remaining morning shower activity has cleared the TAFs sites. Expecting additional scattered convection to develop around 00 UTC tonight. CGI and PAH are the most likely terminals to see thunder, so included VCTS for those locations through 06 UTC. VCSH will be possible at all terminals after 0 UTC through 12 UTC or so. Winds will shift to the northwest behind a cold front. Did not include them in this update, but some models are hinting at MVFR cigs developing behind the front, from about 06 to 12 UTC. Will need to monitor trends for possible inclusion in later updates. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...None. MO...None. IN...None. KY...None. && $$ SHORT TERM...DWS LONG TERM...DRS AVIATION...DWS