Area Forecast Discussion
Issued by NWS Des Moines, IA
Issued by NWS Des Moines, IA
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677 FXUS63 KDMX 291931 AFDDMX Area Forecast Discussion National Weather Service Des Moines IA 231 PM CDT Wed May 29 2024 .KEY MESSAGES... * Pleasant conditions prevail into tomorrow * Shower/storm chances ooze in later Thursday through Friday. Severe threat very low. * Additional/periodic shower/storm chances into next week, but model spread makes details hazy. && .DISCUSSION... Issued at 231 PM CDT Wed May 29 2024 Surface high pressure continues to dominate the region this afternoon, yielding an abundantly pleasant and sunny day. As the inverted surface ridge slowly slides eastward, currently light and variable winds will gradually give way to light southeasterly winds this evening and overnight with highs topping out in the low to mid 70s for most. Western trough along the US-Canada border will quickly push upper level ridging above and across the region tonight, in conjunction with southern stream shortwave energy approaching. Those combined will work to provide our next opportunity for a few showers/storms latter Thursday and through Friday. The overall severe risk remains very low with best ingredients/opportunities shunted southward. Deterministic synoptic models have begun hinting at more of a split scenario for precip coverage with strongest forcing centered northward into SD/ND/MN and southward over KS/MO/OK/AK between the two aforementioned waves. This has also begun to be reflected within ensemble guidance. As such, greatest uncertainty in precipitation coverage and amounts lies over, you guessed it, Iowa. Have nominally scaled bag PoPs, but did not get too aggressive with it just yet. Additional shortwave energy moving through the developing zonal upper flow pattern will allow for periodic shower/storm chances through the weekend and potentially into/through the middle of next week. PoPs are inevitably too prolonged within the forecast, but model discrepancies in handling of the shortwaves lends to degraded confidence in higher or drier windows for PoPs at the moment. Similar to the Thur/Fri system above, the severe threat appears quite low for the most part. Out on Day 6/7, deterministic guidance is in fair agreement of an upper trough dragging a cold front across the region, which may provide our next severe opportunity as Gulf moisture is also forecast to return to the area early-mid next week. Lots of time for details to change/shift though, but something to casually watch. Temperatures through the forecast period will see a warming trend after Friday with high temperatures surging into the 80s by Sunday and into next week. Tuesday currently shapes up to be the warmest of days with progged 850mb temps into the teens deg C, including a shot at touch 90 if forecast trends warmer. && .AVIATION /18Z TAFS THROUGH 18Z THURSDAY/... Issued at 1233 PM CDT Wed May 29 2024 VFR conditions to prevail across all TAF sites through the period. Fair weather cumulus will be most prevalent as you travel east, with FEW/SCT around 5kft. Light and variable winds will give way to SE winds through the day, picking up a bit toward the end of the period with winds around 14G21KTS around northern sites KFOD/KMCW and a bit lighter elsewhere. && .DMX WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Curtis AVIATION...Curtis