textproduct: Des Moines

KEY MESSAGES

- Blizzard and High Wind Warnings in effect into this evening.

- Arctic cold air arrives Thursday afternoon and night. Wind Chill values of 25 to 40 below zero expected later Thursday night into Friday morning.

- Arctic cold continues into Saturday with additional waves likely into next week.

DISCUSSION

Issued at 248 PM CST Wed Jan 21 2026

A strong system is currently moving through Iowa with the main cold front extending across the northwest third of the state. Snow showers are moving across parts of central and north central Iowa ahead of the boundary and there have been a few lightning pulses over northwest Iowa with a few of these snow showers. Per this winter trend, the wind is once again over performing with numerous 60+ mph gusts upstream over northwest Iowa/northeast Nebraska and South Dakota. This wind is located along and behind the cold front and is tracking well with a 925 mb wind max bubble that will be moving across much of the forecast area this afternoon and into the early evening. With snowfall last night of 1 to 3 inches and snow showers moving across northern Iowa and the potential for another 1 to 2 inches today, we upgraded to a blizzard warning for north central Iowa. A high wind warning has been placed over the remainder of the area with the potential of 65 mph wind gusts as that wind max and strong pressure height rises move through. Deterministic model soundings are suggesting mixing to above 750 mb is required to get some of these winds to the surface, further supported by the strong cold advection.

Headlines have been extended to 11 pm though the wind should be diminishing prior to then. Several waves of snow showers and horizontal convective rolls are ongoing upstream across the Dakotas and this should impact parts of northern Iowa into the overnight. Headlines will be downgraded early as conditions allow.

Much of the focus this forecast period was on today and tonight and upgrades to headlines. The Arctic air intrusion arrive Thursday afternoon north and across the rest of the area Thursday night is the other area of emphasis. This is the coldest air so far this winter season. Models continue to show an extremely cold core of Arctic air arriving over the Northern Plains on Thursday with an impressive -38C to -39C centered over Grand Forks, ND Thursday afternoon. Temperatures won't be quite that cold into Iowa by -30C at 850 mb may move across northern Iowa. The main concern over Iowa is very cold temperatures with highs mostly below zero on Friday and wind chills of 25 to 40 below zero over the entire area. We will likely need to upgrade to an Extreme Cold Warning. Have opted to leave as a watch for now until the current system moves through and focus on the cold headlines tonight into Thursday morning.

These Arctic cold intrusions are very often accompanied with shallow horizontal convective roles which result in waves of snow showers that can quickly reduce visibilities. Will continue to monitor this. The long wave pattern through much of next week features mostly strong northerly flow into Iowa with several systems moving thorugh the flow. This will likely result in an overall cold period with waves of Arctic air.

AVIATION /00Z TAFS THROUGH 00Z FRIDAY/

Issued at 538 PM CST Wed Jan 21 2026

Have trended down the winds for the next 3 hours for all sites, and lessened restrictions due to decreasing coverage in snow. Northeast sites will continue to see vsby reductions from BLSN. Gusts will cease by 06z and then return by midday Thursday. Monitoring the potential for additional snow showers in northern Iowa After 18z, but coverage and intensity will be much lower compared to today.

DMX WATCHES/WARNINGS/ADVISORIES

Blizzard Warning until 11 PM CST this evening for IAZ004>007- 015>017-023>028-038-039. Extreme Cold Watch from late Thursday night through Saturday morning for IAZ004>007-015>017-023>028-033>039-044>050-057>062- 070>075-081>086-092>097. High Wind Warning until 11 PM CST this evening for IAZ033>037- 044>050-057>062-070>075-081>086-092>097. Winter Weather Advisory until 11 PM CST this evening for IAZ034>037-050.