


Area Forecast Discussion
Issued by NWS Des Moines, IA
Issued by NWS Des Moines, IA
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550 FXUS63 KDMX 161944 AFDDMX Area Forecast Discussion National Weather Service Des Moines IA 244 PM CDT Thu Oct 16 2025 .KEY MESSAGES... - Warm and breezy to end the week, with highs today and Friday in the mid-70s to lower 80s. - An approaching cool front will bring more showers and thunderstorms at times Friday through Saturday. The overall severe weather threat is low, but a few storms could be strong mainly across the southeastern half of Iowa late Friday. - Dry and breezy conditions on Sunday may promote elevated fire weather concerns. - Additional shower chances (<30%) return late Monday into Tuesday && .DISCUSSION... Issued at 244 PM CDT Thu Oct 16 2025 On and off rain showers and weak storms riding the large-scale ridge continued across parts of central to eastern Iowa this morning, though the increasing warm air advection into the state through the day has elongated the ridge vertically to the north, pushing these showers out of the state with dry conditions across Iowa this afternoon. The increase in low-level southerly flow in the area, along with a tightened pressure gradient overhead has brought breezy winds, especially northern/western Iowa where gusts up to 25+ knots have occasionally been reported so far today and will continue into the early evening before decreasing slightly. This increase in warm air advection has been warming temperatures over the region as well, though there is a sharp difference in values as afternoon values range in the mid to upper 70s across the southwest half of the state, while the northeast is cooler in the upper 50s to 60s. This is largely attributed to the clearing skies southwest allowing for better warming, while further north and east still have lingering low to mid-level cloud cover. These clouds will continue to lift completely out of Iowa, and besides some occasional high clouds, should see warming continue with highs expected to reach into the mid 70s to low 80s, warmest southwest. Looking further west, lee cyclogenesis has formed a large area of low pressure centered over eastern Colorado into western Nebraska/Kansas in relation to a large trough that has been circulating over the western CONUS over the past few days now. This low pressure system is expected to track northeast into the Upper Midwest region this evening, particularly over the Dakotas into Minnesota, keeping Iowa well within the warm sector and remaining dry tonight into early Friday morning. Lows tonight are expected to fall into the upper 50s to low 60s. A rather weak northeast to southwest oriented frontal boundary from the aforementioned system, along with a push of moisture into western Iowa will bring the next chance for showers after sunrise Friday, tracking slowly eastward through the day before stalling near east-central to eastern Iowa by the evening. Following the weak frontal passage over most of the state, temperatures will only be a touch cooler in the mid to upper 70s, while ahead of the front, values reach into the low 80s. Guidance continues to indicate a better push of moisture into east/southeast Iowa where the warmer air will be located by the early evening, along with a gradually strengthening low level jet that will result in a higher potential for showers and even storms to develop. Instability present over the area, along with favorable shear around or above 30+ knots will allow for at least a low chance for a few strong storms. Looking further among models indicates a variation in instability over south/east Iowa with the NAM/GFS showing values under 500 J/kg, while the HRRR/RAP indicate higher values around 500-1000 J/kg by Friday evening, which seems more reasonable given the warm and moist environment ahead of the boundary. The primary hazards with any strong storms, with even a low severe risk, would be small hail and gusty winds. The SPC has the area in a General Thunder outlook, though a Marginal Risk has been introduced over a portion of far southern Iowa in the afternoon update given the potential that currently exists. Something to certainly monitor over the next several hours. Showers and weaker storms look to linger over eastern/southern Iowa into Saturday morning. Following a brief dry period through Saturday afternoon for much of Iowa, a rather potent lobe of shortwave energy within the larger circulation into southern Canada looks to pivot down into Iowa Saturday evening, with another push of moisture into eastern Iowa towards the Ohio Valley region and forcing for lift which will result in the chance for redevelopment of showers and storms over the same areas. Latest trends among guidance though seem to keep much of this activity further south and east, with most if not all activity near the boundary out of the state where the better parameter space looks more likely to setup. However, weaker lift into Central Iowa with lingering moisture along an ahead of an 850mb cold front could bring a quick shot of light showers Saturday evening. Lingering weaker showers may continue into early Sunday as well, then conditions dry out across the region as dry air spreads overhead with a large area of surface high pressure dropping southeast across the western part of the Central Plains. This will come with a rather strong push of northwesterly flow into Iowa that will bring much cooler temperatures into the area, with highs expected in the 60s. Breezy conditions with lower RH values in the upper 20s to low 30s could lead to a potential for elevated fire weather conditions as well. The dry conditions per longer range guidance looks to hold into the start of the work week, with a switch back o southwesterly flow ahead of another surface low tracking eastward across the Upper Midwest, extending a boundary into Iowa by Monday evening before departing Tuesday. Per GFS, weak moisture and lift over the state keeps chances mainly over north/northeast Iowa, though the Euro indicates more extensive coverage across much of Iowa. Differences like this are expected given this is several days out so will have to watch, but not anticipating much impact in terms of significant rainfall or storms at this time. && .AVIATION /18Z TAFS THROUGH 18Z FRIDAY/... Issued at 1233 PM CDT Thu Oct 16 2025 Lingering low stratus covers northeast Iowa this afternoon yet, with IFR/LIFR ceiling expected to lift over the next few hours as the showers continue to lift northeast. Otherwise, some high clouds will pass through, especially into Friday ahead of the next boundary arriving into western/northern Iowa around 12z, gradually pushing eastward. Therefore have included PROB30 mentions at KFOD and KMCW at this time, with additional updates expected over the next issuances. Winds today will remain breezy with gusts up to 25 knots, especially over northern Iowa before decreasing a bit tonight, though LLWS is expected across the terminals into Friday. && .DMX WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Bury AVIATION...Bury