379 FXUS63 KDMX 301949 AFDDMX Area Forecast Discussion National Weather Service Des Moines IA 249 PM CDT Fri Oct 30 2026 .KEY MESSAGES... - Rain chances increasing this evening, lasting through at least the morning hours Saturday. Sprinkles/very light rain will hang on for Halloween night. - Next chance of rain returns Monday with thunderstorms possible Monday afternoon/evening. Rain will linger through Wednesday. - Highs in the 60s common though rain and clouds could drop highs into the 50s in spots. && .SHORT TERM /THROUGH SATURDAY/... Issued at 159 PM CDT Fri Oct 30 2026 Dry air has kept rain chances mostly in the south today with sunshine appearing from the eroding stratus in between the two bands of moisture. The southern band will move north and across the state tonight. This is in response to a weak synoptic shortwave that will move right over the state this weekend. A few thunderstorms will be possible along the leading edge of the rain this evening, but lightning will be sparse. (25% chance of lightning) Most of the rain tonight will fall in northern Iowa and will total between a quarter and half inch. Clouds will remain over the state for Halloween and some sprinkles/light showers will hang on in the central and southern parts of the state. Trick-or-Treating won't be a wash, but it will feature some of this light rain. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... Issued at 159 PM CDT Fri Oct 30 2026 Height rises on the exiting half of the shortwave will suppress rain chances Sunday and the main moisture axis will be pulled towards the lee side troughing. Southeast and eastern Iowa may see some very light rain early. Highs will start to recover into the upper 60s and near 70, but a prolonged period of rain and some storms will arrive to start next week. The southern stream wave will eject into the plains, enhancing the low and midlevel jet in the warm sector. At this range, deterministic runs bring MUCAPE values around the 300 J/kg range into southern Iowa. As mentioned yesterday, the potential for surface-based severe weather is heavily challenged by morning rain and lingering cloud cover. Moderate wrap-around rain stays in the state for Tuesday and partially into Wednesday. NBM QMD guidance shows that much of the state has around a 50% chance of exceeding 2" of rain, which matches the early convective nature as well as the very high PWATs (1.5") by November standards. The progressive nature of convection and the long-duration of rain will reduce potential hydrologic impacts. Highs will cool into the 50s following the system's departure and the upstream pattern will remain active and amplified. && .AVIATION /18Z TAFS THROUGH 18Z SATURDAY/... Issued at 1245 PM CDT Fri Oct 30 2026 Stratus is breaking apart in parts of southern Iowa which could offer a period of VFr in the short term for DSM and OTM, mainly. Showers have stayed further south than previously anticipated, so the arrival time has been delayed for most sites and rain remains in the short term for KOTM. Lower cigs will gradually focus into northern Iowa overnight. Can't rule out residual sprinkles as cigs lift late in the period, but confidence is low in vsby impacts. && .DMX WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Jimenez LONG TERM...Jimenez AVIATION...Jimenez
