082 FXUS63 KDMX 260829 AFDDMX Area Forecast Discussion National Weather Service Des Moines IA 329 AM CDT Tue Mar 26 2019 .DISCUSSION.../Today through Monday/ Issued at 329 AM CDT Tue Mar 26 2019 .Overview: Quiet sensible weather today with a warm and blustery day on tap for Wednesday. Rain and thunderstorm chances increase Wednesday night into Thursday with precipitation chances lingering into early Saturday. The rain may change to snow at night, particularly Friday. .Details: A shortwave trough and the PV anomaly riding down a ridge building into the region will largely pass southwest of the area today. The shortwave will foster more clouds over western Iowa compared to eastern Iowa. These clouds are already present over west central and southwest Iowa back into eastern Nebraska and South Dakota as seen on GOES-East Nighttime Microphysics RGB. Any light rain should stay west of central Iowa with forecast currently dry, though they could dribble into areas around Atlantic to Bedford this morning. Meanwhile, warm air advection will begin to increase as the flow at the surface and low levels becomes from the southwest as high pressure transitions into the Ohio Valley today. This will allow temperatures to be about 5 degrees higher than yesterday. With the pressure gradient tightening on Wednesday, warm air advection will strengthen along with increasing winds. Wind gusts continue to trend downward as far as upper end potential. Two nights ago, BUFKIT GFS soundings were suggesting wind gusts near or over 40 knots across much of northern and central Iowa as boundary layer mixing was near to just above 1km. Now, wind gusts closer to 30 knots seems more likely. The strong winds are still there in the low levels, but so now is a low level inversion that will limit boundary layer mixing to 700 to 800m at peak heating. With 850mb temperatures on Wednesday about 7 to 9 degrees higher than today, will see temperatures soar into the 60s over central Iowa with low 70s in western Iowa and perhaps a few spots in central Iowa. By Wednesday evening, a cold front will be moving into northwest Iowa. The arrival of this front has continued to come earlier and earlier with it now expected to be over southeast Iowa and northwest Missouri by midday Thursday. Thus, the passage does not coincide with peak heating and this will limit overall storm potential. Still, there will be enough forcing for rain and MUCAPE of perhaps 500 J/kg so will keep thunder in the forecast. The front will stall over northern Missouri and keep rain chances mainly focused over southern Iowa Thursday night. As a shortwave trough comes out of the central Rockies and passes through the region, broader scale Q- vector convergence will foster rain chance over all of Iowa. The highest chances for rain will be over the southern 2/3rds of the state with thunder chances also over southern Iowa. As the shortwave moves off to the east late Friday night into Saturday, this will bring an end to the precipitation on the first half of Saturday. The rain may change to snow both early Friday and again Friday night, but warm surface temperatures should help to offset snow totals. Still could be some minor accumulations. Highest liquid totals still look to fall over the southern half of the state with deterministic guidance ranging from a half an inch to 2 inches. Given the current saturated state of soils, additional moisture is not needed and may contribute to rises on streams and rivers. This weekend will be dry, but cool as high pressure follows behind the departing shortwave. High temperatures will be about 10 degrees below normal. && .AVIATION.../For the 06Z TAFS through 06Z Tuesday night/ Issued at 1137 PM CDT Mon Mar 25 2019 Expecting a SCT to BKN mid to high level VFR deck through the forecast period. Sfc wind will be lgt and vrb becoming southerly around 10kts around 18Z through the end of the period. && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ DISCUSSION...Ansorge AVIATION...FAB