Winter Weather in Iowa, December 27 to 28, 2018

Name: Winter Weather in Iowa, December 27 to 28, 2018
Start: 2018-12-27T14:00
End: 2018-12-28T12:00
Location: Iowa

December 27 to 28, 2018 · NWS FSD · 1 event in 1 county or zone

Where it happened

Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 1

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS FSD wrote it up.

A long duration winter weather event ensued after Christmas as a full-latitude trough moved through the Rockies on December 26, initiating cyclogenesis as the mid-level wave closed off and lifted northeast from TX into KS by early on December 27. A leading pulse of warm advection ahead of the main system produced a swath of mixed precipitation on the 26th into early on the 27th across southeast SD and southwest MN. This area weakened before the main wave lifted across the area on the 27th and sheared into northern Minnesota by early morning December 28. A significant dry slot pushed across Iowa early on the 27th allowing for a brief change in precipitation to liquid or freezing precipitation. Heavier snowfall redeveloped within the TROWAL during the 27th and continued through the following night across southeast SD into southwest MN.

As the area of low pressure strengthened moving across Iowa during the afternoon of December 27, winds increased with gusts of 40 to 55 mph common into the early morning of December 28.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Sioux Falls, SD wrote its last area forecast discussion before the first event at Dec 27, 12:04 PM CST, 1 hour 56 minutes earlier.

Area forecast discussion, Dec 27, 12:04 PM CST, 1 hour 56 minutes before

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Hazardous weather outlook, Dec 27, 4:20 AM CST, 9 hours 40 minutes before

Hazardous Weather Outlook
National Weather Service Sioux Falls SD
420 AM CST Thu Dec 27 2018

IAZ001-MNZ071-072-080-089-097-098-NEZ013-SDZ038>040-050-052>070-
281030-
Lyon IA-Lincoln MN-Lyon MN-Murray-Nobles-Pipestone-Rock-Dixon-
Beadle-Kingsbury-Brookings-Gregory-Jerauld-Sanborn-Miner-Lake-
Moody-Brule-Aurora-Davison-Hanson-McCook-Minnehaha-Charles Mix-
Douglas-Hutchinson-Turner-Lincoln SD-Bon Homme-Yankton-Clay SD-
420 AM CST Thu Dec 27 2018

This Hazardous Weather Outlook is for portions of northwest Iowa,
southwest Minnesota, northeast Nebraska, central South Dakota,
east central South Dakota, south central South Dakota, and
southeast South Dakota.

.DAY ONE...Today and Tonight

A major winter storm with occasional heavy snow will develop
through the morning. The heaviest snow amounts will be near the
James Valley with 6 to 12 inches while closer to Interstate 29 2
to 4 inches is expected. Along with the heavy snow will be
northwest winds gusting to around 45 mph which will create brief
whiteout conditions.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

Much colder air will move into the region behind this winter
storm for Friday and Saturday. Wind chills in the single digits
and teens below zero appear likely Friday night into Saturday
morning.

Another blast of cold air Monday night into Tuesday will bring
wind chill values of 20 below to 30 below zero.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

IAZ002-003-012>014-020>022-031-032-MNZ081-090-NEZ014-SDZ071-
281030-
Osceola-Dickinson-Sioux-O'Brien-Clay IA-Plymouth-Cherokee-
Buena Vista-Woodbury-Ida-Cottonwood-Jackson-Dakota-Union-
420 AM CST Thu Dec 27 2018

This Hazardous Weather Outlook is for portions of northwest Iowa,
west central Iowa, southwest Minnesota, northeast Nebraska, and
southeast South Dakota.

.DAY ONE...Today and Tonight

Periods of moderate rain will cause local streams, creeks and
rivers to rise today. A few could exceed bankfull. Colder air
will move in tonight and allow rain to change to snow. Snowfall
amounts should be less than 2 inches but winds gusting to around
40 mph will reduce the visibility at times.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

Much colder air will move into the region behind this winter
storm for Friday and Saturday. Wind chills in the single digits
and teens below zero appear likely Friday night into Saturday
morning.

Another blast of cold air Monday night into Tuesday will bring
wind chill values of 15 below to 25 below zero.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

In the hours before

Local storm report, Dec 27, 12:03 PM CST, 1 hour 57 minutes before

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Local storm report, Dec 27, 1:26 PM CST, 34 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
126 PM CST THU DEC 27 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1219 PM     SNOW             1 SE TEA                43.44N 96.82W
12/27/2018  M2.0 INCH        LINCOLN            SD   TRAINED SPOTTER

            SOCIAL MEDIA REPORT.

&&

APT

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

1 winter weather. Local standard time, as filed.

Winter Weather, Lyon

When: December 27, 2:00 PM CST to December 28, 12:00 PM CST
Where: Lyon forecast zone
Reported by: COOP Observer
Coordinates: 43.381, -96.210 (the zone’s center; the record gives no point)

After a period of light wintry mix, snow developed and winds increased across far southeast South Dakota, southwest Minnesota, far northwest Iowa and northeast Nebraska. Snowfall generally totaled 3 to 5 inches, with 4 to 6 inches near southern Sioux Falls. Other snowfall totals were 5.9 inches at Worthington MN, 5.0 inches at Canton SD, 4.0 inches near Vermillion SD, 3.5 inches near Larchwood IA, 3.0 inches at Luverne, MN and 2.3 inches at Concord NE. Visibility was reduced to a mile or less while heavier snowfall occurred, and winds were gusting to 37 mph at Slayton, 38 mph at Luverne and 46 mph at Worthington.

What these are

Winter Weather: Snow, sleet or freezing rain below warning levels that still caused disruption, damage or casualties.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Iowa in 2018 Every state in 2018 This day in weather history Warnings in Iowa, December 2018

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 810353.