394 FXUS63 KDMX 110350 AFDDMX Area Forecast Discussion National Weather Service Des Moines IA 1050 PM CDT Thu Apr 10 2025 ...Updated for the 06z Aviation Discussion... .KEY MESSAGES... -Additional shower activity with gusty winds and some small hail potential into the early evening today -Quiet Friday, warming through the weekend and breezy -Showers and storms possible mainly north late Saturday into Sunday, then slightly cooler into next week; very breezy Monday && .DISCUSSION... Issued at 319 PM CDT Thu Apr 10 2025 Light spotty rain showers with a passing shortwave brought very minor accumulations of rainfall this morning, concentrated mainly along with I-80 corridor with values generally under a tenth of an inch. As the departing weak low pressure system continues to track eastward out of the Central Plains into the Ohio Valley, another wave of weaker forcing currently moving through the state is bringing continued spotty showers, with coverage mainly along and east of I-35. Model soundings depict relatively low-end instability that will continue to bring some thunder/isolated thunderstorms through the rest of this afternoon to early evening, with gusty winds as well given the presence of dry air in the low levels. Any showers and storms should depart into the mid to late evening tonight. However, any gusts should remain below severe limits but will keep a close eye this activity. Pea size hail remains a possibility through the afternoon, given that the freezing level heights are right around the LCL, paired with fairly steep mid-level lapse rates, which allowed for some small hail in Polk County early this afternoon where a stronger cell moved across. Northwest winds behind the aforementioned system have increased across the state into the afternoon, as gusts through the morning were a bit higher than forecast around 30mph and even some isolated gusts around 35 mph+ in northern Iowa. Spotty sunshine between the areas of cloud cover is allowing for winds to mix down to the surface and should continue at times today. As thicker and more widespread cloud cover moves down into Iowa from Minnesota this afternoon, wind gust values should generally remain in the 25-30 mph range, isolated to 35mph out of the northwest before decreasing this evening. Overnight lows are expected to fall into the upper 30s to low 40s over the forecast area, along with dry conditions. Into Friday, a large area of high pressure ahead of a building mid- level ridge will slide into the Midwest, which will result in quiet weather overhead. Cloud cover will decrease into the afternoon, with slightly cooler temperatures in the upper 50s to low 60s and light winds for the majority of the day out of the north. By Friday evening and especially into Saturday morning, a change in the low level flow pattern is expected as winds shift southeasterly. With a thermal ridge moving overhead, warmer air will move into the state as winds increase out of the south. Winds are expected to reach into the upper 60s to low 70s, warmest west, paired with gusty winds upwards of 20-30 mph, isolated to 35 mph. These warmer temperatures and breezy winds, paired with minimum RH values in the mid to upper 30s across the area will lead to elevated fire weather conditions, especially over central and northern Iowa where green-up of fuels is not as prominent as further south. A developing low pressure system off the Rockies Saturday evening per model guidance looks to track eastward into the Central Plains Saturday evening into Sunday, bringing returning chances for rain into Iowa. As it stands with current trends, any rain showers look to occur over northern and eastern Iowa into Minnesota, particularly through the morning before tapering off by the afternoon. A look at model soundings with this activity highlight appreciable shear, instability and steep lapse rates around 8 C/km, which point to some potential for at least a few strong storms. Notable differences in coverage however can be seen between models, as the NAM dries out by Sunday afternoon into Monday, while the GFS generates wrap-around precipitation over northern/eastern Iowa Sunday night through much of Monday as the low pressure lifts northeast across the Upper Midwest. A close eye will be kept on the severe potential with this system over the next few days, with more details regarding impacts expected to be better known by then. Upper level northwest flow with cold air advection spreading across Iowa Monday as the tightening low pressure departs will lead to cooler and breezy conditions, with winds expected to become quite strong, nearing advisory criteria especially over northern Iowa with gusts up to 35-40+ mph. This cool and dry pattern looks to remain across Iowa through at least Tuesday, with highs in the mid 50s to low 60s. Clear skies Tuesday night into Wednesday will allow for substantial radiational cooling, dropping temperatures into the upper 20s to low 30s mainly along and north of I-80 and a bit warmer in the mid 30s, which paired with decreasing winds looks to bring an increased potential for at least isolated frost until sunrise. However, shifting winds becoming southeasterly will bring a push of at least slightly warmer temperatures into the state through the day, with highs back into the 60s. Another chance for rain showers at least are hinted at in long term model guidance late Wednesday into Thursday, though solutions very substantially in coverage and intensity so will have to see how trends play out over the next several runs. && .AVIATION /06Z TAFS THROUGH 06Z SATURDAY/... Issued at 1050 PM CDT Thu Apr 10 2025 Few changes to previous package. Cigs lowering to MVFR northeast and central and slowly improving through 19z when all sites become VFR. Winds generally light overnight, though a few gusts yet at DSM and possibly OTM before becoming light northeast then VAR between 12z and 19z. /rev && .DMX WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Bury AVIATION...REV