657 FXUS63 KDMX 302333 AFDDMX Area Forecast Discussion National Weather Service Des Moines IA 633 PM CDT Fri Oct 30 2026 ...Updated for the 00z Aviation Discussion... .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 FRIDAY/... 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 /00Z TAFS THROUGH 00Z SUNDAY/... Issued at 627 PM CDT Fri Oct 30 2026 VFR conditions are prevailing across the area; however, showers are starting to develop in northwest Iowa and are moving toward the DMX coverage area. KFOD will be the first to experience showers before showers become more scattered through the overnight. Confidence is largely lacking on where these showers will develop, especially at KFOD and KDSM; therefore, PROB30s were used to cover the scattered chances of showers. Otherwise, higher confidence existed at KMCW, KALO and KOTM; therefore, prevailing showers we added for the late overnight/early morning hours. Post-precipitation low CIGS and low VSBY will be possible through 17Z before gradually improving to VFR Saturday afternoon. Lastly, winds will be decreasing overnight to light and variable and will stay light and variable for the remainder of the TAF window. && .DMX WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Jimenez LONG TERM...Jimenez AVIATION...Vorst
