Cold in Wyoming, December 31, 2017

Name: Cold in Wyoming, December 31, 2017
Start: 2017-12-31T00:00
End: 2017-12-31T23:59
Location: Wyoming

December 31, 2017 · NWS UNR · 6 events in 6 counties and zones

An Arctic airmass with bitter cold temperatures settled over the area. Low temperatures were 10 below to 25 below zero with wind chills as low as 35 below zero.

Where it happened

Every event with a place to put it; 5 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: 6

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 UNR wrote it up.

An Arctic airmass with bitter cold temperatures settled over the area. Low temperatures were 10 below to 25 below zero with wind chills as low as 35 below zero.

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 Rapid City, SD wrote its last area forecast discussion before the first event at Dec 30, 10:35 PM MST, 1 hour 25 minutes earlier.

Area forecast discussion, Dec 30, 10:35 PM MST, 1 hour 25 minutes before

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
1035 PM MST Sat Dec 30 2017

.DISCUSSION...(This Evening Through Saturday)
Issued at 247 PM MST Sat Dec 30 2017

Cyclonic flow aloft continues across much of the CONUS today with
arctic air sitting across the northern Plains into the Great Lakes
through New England. A strong upper wave is pushing through the area
right now bringing moderate to heavy snowfall across western South
Dakota. Surface front is straddling Wyoming into eastern Colorado
south to OK/TX. Temperatures are near to well below zero across the
region. Subsidence behind the upper wave will bring in drier air to
the area tonight, with snowfall ending over the next few hours.
Extremely cold temperatures will continue Sunday with lows of 10
below to 25 below zero and highs zero to 10 below. Wind chills are
still expected to be in the 15 below to 40 below range tonight into
tomorrow morning with not much recovery during the day Sunday. Then
temps and wind chills will drop right back down Sunday night into
Monday. Will continue with previously issued wind chill headlines.
Upper ridging will build into the region late Monday into Tuesday
with warm air advecting in. After another cold day Monday, Tuesday's
highs will be in the 20s to mid 30s. Similar temps are expected
Wednesday. A gradual warming of temps are then expected toward the
end of next week with highs in the 30s to low 40s. Dry weather is
expected through next week.

&&

.AVIATION...(For the 06Z TAFS Through 06Z Sunday Night)
Issued At 1035 PM MST Sat Dec 30 2017

MVFR/VFR conditions are expected overnight across the area, with
MVFR CIGS primarily confined to the Black Hills and northeastern
WY. Could continue to see some brief periods of SCT/FEW clouds
across northeast WY/KGCC through the night, but believe that
BKN/OVC MVFR CIGS will prevail. Occasional light snow showers or
flurries will also continue to be possible overnight. Conditions
should improve to VFR area-wide on Sunday morning.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...Wind Chill Advisory until 11 AM MST Monday for SDZ024>029-041-
     072-074.

     Wind Chill Warning until 11 AM MST /noon CST/ Monday for SDZ001-
     002-012>014-030>032-042>044-046-047-049-073.

WY...Wind Chill Advisory until 11 AM MST Monday for WYZ054>058-071.

&&

DISCUSSION...13
AVIATION...Sherburn

Hazardous weather outlook, Dec 30, 9:05 PM MST, 2 hours 55 minutes before

Hazardous Weather Outlook...UPDATED
National Weather Service Rapid City SD
905 PM MST Sat Dec 30 2017

SDZ001-002-012>014-030>032-042>044-046-047-049-073-311400-
Harding-Perkins-Butte-Northern Meade Co Plains-Ziebach-
Custer Co Plains-Pennington Co Plains-Haakon-Oglala Lakota-
Jackson-Bennett-Mellette-Todd-Tripp-Southern Meade Co Plains-
905 PM MST Sat Dec 30 2017 /1005 PM CST Sat Dec 30 2017/

This Hazardous Weather Outlook is for portions of western South
Dakota.

.DAY ONE...Tonight

Wind chills of 25 below zero to around 40 below zero can be
expected tonight. A wind chill warning is in effect.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

Bitterly cold wind chills are expected Sunday through Monday
morning with readings from 25 below zero to around 40 below zero
at times, especially at night.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today.

&&

Stay tuned to NOAA weather radio for further updates...or check
our web site at weather.gov/rapidcity

SDZ024>029-041-072-074-WYZ054>058-071-311400-
Northern Black Hills-Northern Foot Hills-Rapid City-
Southern Foot Hills-Central Black Hills-Southern Black Hills-
Fall River-Sturgis/Piedmont Foot Hills-Hermosa Foot Hills-
Northern Campbell-Southern Campbell-Western Crook-
Wyoming Black Hills-Weston-Northeastern Crook-
905 PM MST Sat Dec 30 2017

This Hazardous Weather Outlook is for portions of northwestern
South Dakota...southwestern South Dakota...the Black Hills...and
northeast Wyoming.

.DAY ONE...Tonight

Wind chills of 15 below to around 30 below zero can be expected
tonight. A wind chill advisory is in effect.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

Bitterly cold wind chills are expected Sunday through Monday
morning with readings from 15 below zero to 30 below zero at
times, especially at night.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today.

&&

Stay tuned to NOAA weather radio for further updates...or check
our web site at weather.gov/rapidcity

In the hours before

Local storm report, Dec 30, 6:31 PM MST, 5 hours 29 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RAPID CITY SD
631 PM MST SAT DEC 30 2017

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

0631 PM     SNOW             HOOVER                  45.11N 103.27W
12/30/2017  M5.0 INCH        BUTTE              SD   CO-OP OBSERVER

            STORM TOTAL SNOWFALL

&&

KDS

Local storm report, Dec 30, 6:34 PM MST, 5 hours 26 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RAPID CITY SD
634 PM MST SAT DEC 30 2017

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

0600 PM     SNOW             2 E DOWNTOWN STURGIS    44.41N 103.48W
12/30/2017  M3.0 INCH        MEADE              SD   CO-OP OBSERVER

            72 HOUR SNOWFALL

&&

KDS

Local storm report, Dec 30, 6:36 PM MST, 5 hours 24 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RAPID CITY SD
636 PM MST SAT DEC 30 2017

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

0700 AM     SNOW             21 NW FAITH             45.23N 102.34W
12/30/2017  M5.5 INCH        PERKINS            SD   COCORAHS

            72 HOUR SNOWFALL

&&

KDS

Local storm report, Dec 30, 6:37 PM MST, 5 hours 23 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RAPID CITY SD
637 PM MST SAT DEC 30 2017

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

0700 AM     SNOW             11 NNE WESTON           44.78N 105.25W
12/30/2017  M5.3 INCH        CAMPBELL           WY   COCORAHS

            72 HOUR SNOWFALL

&&

KDS

Local storm report, Dec 30, 6:43 PM MST, 5 hours 17 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RAPID CITY SD
643 PM MST SAT DEC 30 2017

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

0643 PM     SNOW             8 WNW USTA              45.25N 102.31W
12/30/2017  E6.0 INCH        PERKINS            SD   TRAINED SPOTTER

            STORM TOTAL SNOWFALL

&&

KDS

Local storm report, Dec 30, 6:50 PM MST, 5 hours 10 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RAPID CITY SD
650 PM MST SAT DEC 30 2017

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

0650 PM     SNOW             6 SW HERMOSA            43.79N 103.29W
12/30/2017  E4.0 INCH        CUSTER             SD   TRAINED SPOTTER

            STORM TOTAL SNOWFALL

&&

KDS

The radar

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

Open the radar archive at this moment

Event by event

6 cold/wind chill. Local standard time, as filed.

Cold/Wind Chill, Northeastern Crook

When: December 31, 12:00 AM MST to 11:59 PM MST
Where: Northeastern Crook forecast zone
Reported by: Mesonet

Cold/Wind Chill, Northern Campbell

When: December 31, 12:00 AM MST to 11:59 PM MST
Where: Northern Campbell forecast zone
Reported by: ASOS
Coordinates: 44.248, -105.548 (the zone’s center; the record gives no point)

Cold/Wind Chill, South Campbell

When: December 31, 12:00 AM MST to 11:59 PM MST
Where: South Campbell forecast zone
Reported by: Mesonet
Coordinates: 44.248, -105.548 (the zone’s center; the record gives no point)

Cold/Wind Chill, Western Crook

When: December 31, 12:00 AM MST to 11:59 PM MST
Where: Western Crook forecast zone
Reported by: Mesonet
Coordinates: 44.589, -104.570 (the zone’s center; the record gives no point)

Cold/Wind Chill, Weston

When: December 31, 12:00 AM MST to 11:59 PM MST
Where: Weston forecast zone
Reported by: Mesonet
Coordinates: 43.841, -104.568 (the zone’s center; the record gives no point)

Cold/Wind Chill, Wyoming Black Hills

When: December 31, 12:00 AM MST to 11:59 PM MST
Where: Wyoming Black Hills forecast zone
Reported by: Mesonet
Coordinates: 44.215, -104.569 (the zone’s center; the record gives no point)

What these are

Cold/Wind Chill: Cold or wind chill below warning criteria that caused deaths, injuries or damage.

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

The same day elsewhere

Every storm in Wyoming in 2017 Every state in 2017 This day in weather history Warnings in Wyoming, December 2017

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: 731276, 731278, 731279, 731280, 731281, 731282.