012 FXUS63 KDMX 310536 AFDDMX Area Forecast Discussion National Weather Service Des Moines IA 1236 AM CDT Sat May 31 2025 ...Updated for the 06z Aviation Discussion... .KEY MESSAGES... - Temperatures warm into the upper 80s through the weekend with upper level smoke making for hazy skies. - Thunderstorms return to the area on Tuesday and we continue to monitor the potential for severe storms. && .DISCUSSION... Issued at 229 PM CDT Fri May 30 2025 While most of Iowa is cloud free this afternoon, one cannot look up into a blue sky. Smoke from wildfires across Canada has pushed into Iowa today and satellite imagery shows this blanketing a large swath of the midwest. This smoke has remained aloft with no observational sites reporting reductions to visibility that would indicate smoke making it to the ground. HRRR and RAP smoke data continues to indicate that this will last through Saturday as well. There is a chance with a passing shortwave on Saturday that some of this smoke may be pulled down to the surface, and this is indicated with slightly elevated concentrations in both RAP and HRRR surface smoke variables. Any impacts to air quality across Iowa will be monitored by the Iowa DNR. Aside from smoke impacts, the passing shortwave should have little tangible impact to Iowa weather with CAMs keeping the area dry. A stray shower my be possible in the afternoon with marginal instability in some HRRR soundings, however confidence to include this in the forecast at this time is low. Meanwhile, temperatures through the weekend and into Monday will soar through the mid to upper 80s with theta e advection into the area as the thermal ridge shifts east. At the same time, a western US trough will dig across the Rockies with an associated surface low ejecting across the midwest by Monday into Tuesday. Impacts to Iowa look to arrive on Tuesday and this will be the next window for thunderstorms. The current track takes the low across Missouri and lifting into Illinois to Wisconsin. That would keep the more robust impacts to the south, however southern Iowa could see some triple point action as the surface low skims southern Iowa. GFS soundings at Lamoni and Des Moines indicate 1200-1500 J/kg surface based CAPE with 100-200+ m2/s2 0-1 km SRH and nicely curved hodographs through roughly the lowest 3 km. While better deep layer shear lags the instability axis in current model runs, this environment remains more than sufficient for supporting organized convection. We`ll continue to fine tune the forecast in the coming days, but this will likely be the next window for severe storms in Iowa. Another system will pass over the area late this week. && .AVIATION /06Z TAFS THROUGH 06Z SUNDAY/... Issued at 1229 AM CDT Sat May 31 2025 VFR conditions ongoing and expected to continue through the TAF period. Lighter winds out of the west overnight will increase again slightly Saturday shifting to be out of the northwest but generally remain near to under 10 knots. Smoke will continue to keep skies hazy and maintained some CIG coverage to account for the smoke aloft. Will continue to evaluate the potential for any smoke impacts making it to the surface but confidence in impacts at any one TAF site remains too low for inclusion at this time. && .DMX WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Hagenhoff AVIATION...05