textproduct: Des Moines

KEY MESSAGES

- Breezy again today into tonight, especially north and northeast where blowing snow will occur once again and may produce additional travel impacts.

- Very cold temperatures will surge in from the northwest later today, with wind chills reaching dangerously low values of 30-40 below zero across most of Iowa by Friday morning. An Extreme Cold Warning is now in effect for the entire area overnight.

- Cold weather will persist through the weekend, but may not be quite as intense as the first 24 hours, therefore an Extreme Cold Watch remains in effect from noon Friday until noon Saturday. Chances for light snow over the weekend have increased to 20-50% at times, with the highest chances near the Missouri border, but any accumulations will be light and without significant blowing snow as winds will be lighter by that time.

DISCUSSION

Issued at 217 AM CST Thu Jan 22 2026

A surface high pressure area is sliding by over Kansas and Missouri early this morning, with diminished winds and partly cloudy skies in our forecast area. A few flurries have been observed over southern Minnesota in association with a mid-level impulse moving by to our north, but these are not expected to appreciably impact our counties this morning. Meanwhile, a large Arctic high pressure area is centered over southwestern Canada and has already begun to build down into the Dakotas overnight and will continue to do so today. The leading edge of this push of colder air will act as an effective cold front, traversing the CWA from northwest to southeast during the day. As it does so, a ribbon of forcing will scoot eastward across central and southern Iowa this afternoon and some short-range models are generating light snow accordingly. However, most of the model suite has been overdone on snowfall the last few days when soundings show a lack of moisture and that is the case again today. With the forcing being so transient and a dry appearance to the soundings, have opted to add flurries central and south but with no measurable accumulation. Of potentially greater impact is that as the cold airmass flows in later today and tonight, it will bring breezy conditions once again especially in our northern and northeastern counties where blowing snow has already been an issue. Forecast soundings show some potential for approximately 30 KT gusts around EST, MCW, and ALO for a couple hours this afternoon, and even overnight with strong cold air advection promoting mixing the gusts should remain in the 20-25 KT range across much of the area after dark. Have increased forecast winds and expanded mention of blowing snow accordingly, with renewed travel impacts expected in areas that still have snow on the ground from yesterday and earlier and are still struggling to clear the blowing snow from yesterday.

As temperatures plummet tonight and north northwest breezes are sustained, wind chills will rapidly fall to dangerous levels across Iowa. Have upgraded the Extreme Cold Watch to a Warning tonight through Friday morning, and moved the start time a few hours earlier in our northern counties where wind chills will already fall into the 30-40 below zero range before midnight. By around sunrise Friday wind chill values will be -30 or lower across nearly our entire service area, excepting perhaps a few counties in the far south and southwest. Slow improvement is then expected during the day as winds continue to diminish and temperatures rise slowly, but it will still remain very cold.

During the day Friday, a very well-advertised and expansive winter storm will take shape across the southern U.S., where an impressive breadth of warnings, watches, and advisories are in effect for the coming weekend. For the last several days most indications have been that the large precipitation shield will remain just south of Iowa, aided by the large high pressure area overhead. However, in the last 24 hours several model runs have resolved the phasing of the 500 MB trough responsible for this system differently, and are now allowing for the northern fringes of the clouds and precipitation to enter our area to varying degrees. Between Friday night and Saturday night nearly all models now have at least a little QPF in southern Iowa, and some runs bring it up to about Highway 20 or so. However, given persistence from earlier forecast trends and the proximity of the large high pressure area and associated dry air entrainment, it is difficult to have much confidence in these wetter solutions, especially in the first part of the event on Friday night and Saturday. After that the Arctic high pressure area will retreat eastward and conditions may be a bit more conducive to light snow, mainly in our south, but by then the brunt of the southern U.S. storm will be moving away to the east. Given this combination of factors, have maintained low to medium (20-50%) POPs across about the southern half of our forecast area around Saturday, highest near the Missouri border, but kept the north dry. This scenario also has impacts on the duration of the extreme cold event referenced above. Increased cloud cover would mitigate both daytime warming and especially nighttime cooling, meaning Saturday night may not be as cold as previously feared. Indeed, the official forecast for this period has eased with Sunday morning lows now forecast "only" from around -10 northeast to 0 southeast, however, there is considerable spread in the possibilities. If trends with the southern winter storm turn back southward and our skies are clearer, then Sunday morning will likely fall to temperatures near Saturday morning levels. However, if skies are mostly cloudy then they may trend even "warmer" than currently advertised. Given these uncertainties, have maintained the Extreme Cold Watch area-wide from noon Friday onward. Subsequent updates will determine whether that is eventually converted to a warning, an advisory, or a mixture.

The long-range forecast for next week still appears relatively active, unfortunately, with Iowa lying on the southern fringes of broadly cyclonic west northwesterly flow aloft, and multiple waves traveling through that flow during the week. The first of these will move through around Sunday night, sweeping out any remaining clouds/light snow from the weekend system and bringing another shot of cooler air with Monday morning lows again below zero statewide. A brief respite will then allow for some temperature moderation around Monday and Tuesday, before more waves move through in the latter half of next week.

AVIATION /12Z TAFS THROUGH 12Z FRIDAY/

Issued at 524 AM CST Thu Jan 22 2026

Patches of low stratus clouds are moving near the Minnesota/Iowa border this morning and may produce brief flurries and MVFR ceilings around FL020-030 at MCW and ALO in the next several hours. Thereafter, as winds increase this afternoon and evening BLSN may reduce visibility at MCW/ALO but the magnitude of visibility reduction will not be as severe as yesterday. Low confidence in magnitude, so have advertised intermittent 3SM BLSN in the TAFs at those sites, but amendments are likely. At the southern terminals, VFR conditions are forecast through the TAF period.

DMX WATCHES/WARNINGS/ADVISORIES

Extreme Cold Warning from 9 PM this evening to noon CST Friday for IAZ004>007-015>017-023>028-033>039-047>050.

Extreme Cold Warning from midnight tonight to noon CST Friday for IAZ044>046-057>062-070>075-081>086-092>097.

Extreme Cold Watch from Friday afternoon through Saturday morning for IAZ004>007-015>017-023>028-033>039-044>050-057>062- 070>075-081>086-092>097.