Near continuous low level moisture and sub freezing temperatures created ideal conditions for rim icing above 8500 feet across the Western Mogollon Rim.
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.
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.
The episode as NWS FGZ wrote it up.
Near continuous low level moisture and sub freezing temperatures created ideal conditions for rim icing above 8500 feet across the Western Mogollon Rim.
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 Flagstaff, AZ wrote its last area forecast discussion before the first event at Dec 24, 2:40 PM MST, 3 hours 20 minutes earlier.
Area Forecast Discussion National Weather Service Flagstaff AZ 240 PM MST Fri Dec 24 2021 .SYNOPSIS...Areas of rain and snow will continue to decrease from west to east today, becoming showery overnight and into Christmas Day. Another period of wet weather and accumulating mountain snow arrives Saturday night, through early Sunday. Yet another period active weather arrives Tuesday and Wednesday, with more widespread rain and snow showers spreading from west to east. && .DISCUSSION...A sub-tropical moisture plume has moved southeast of the CWA this afternoon, with a weak SFC cold front stretching from Yuma to the Four Corners. Snow levels have somewhat stabilized in the 7000-8000 foot range this afternoon, could drop slightly lower in any locally intense convective bands through this evening. Flow aloft flattens pretty quick tonight, with mild hght rises heading into Christmas Day. This will limit any additional showers to shallow, upslope activity, with further impacts becoming unlikely after sunrise Christmas Day. A second s/wv increase the upslope activity again Saturday night and early Sunday, for widespread rain and snow showers over central and western Arizona. Current QPF forecast will result in a few inches of snow in the high country. An even colder pattern and sustained period of upslope flow develops Monday night through Tuesday night/early Wednesday. This will result in round 3 of rain and snow showers, lower snow levels and perhaps moderate snow accumulations in the high country. Breezy to windy conditions exist nearly every day of this forecast period and wind hazard products may be needed from time to time. None are in effect at time of publication. && .AVIATION...For the 00Z package...MVFR/IFR conditions will continue over the Kaibab Plateau, KGCN-KFLG-KSOW in low clouds and fog/mist. Showers will decrease, with only isolated activity remaining after 03Z-05Z. South-southwest winds will continue throughout TAF period with gusts 20-30kts over higher terrain. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...A large trough of low pressure will to bring breezy to windy southwest winds to the area through Sunday. Expect a period of wetting rain and accumulating snow Saturday night/early Sunday. Otherwise. isolated to scattered showers, mainly over the higher terrain. Monday through Wednesday...Cool and breezy with a chance of showers on Monday, widespread wetting rain and snow likely by Tuesday and Wednesday. The snow level will lower during the period as cold air arrives. && .FGZ WATCHES/WARNINGS/ADVISORIES... Winter Storm Warning above 7500 feet until 11 PM MST Friday for AZZ004. Winter Weather Advisory above 7500 feet until 11 PM MST Friday for AZZ011. Winter Weather Advisory above 7000 feet until 5 PM MST this afternoon for AZZ015-016. && PUBLIC...Peterson AVIATION...MAS FIRE WEATHER...MAS For Northern Arizona weather information visit weather.gov/flagstaff
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
1216 PM MST FRI DEC 24 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1145 AM SNOW MOUNTAINAIRE 35.09N 111.66W
12/24/2021 E5.0 INCH COCONINO AZ PUBLIC
PUBLIC REPORT WITH PHOTO FROM FACEBOOK.
SNOWFALL CONTINUES AT TIME OF REPORT.
&&
NLPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
1219 PM MST FRI DEC 24 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1206 PM SNOW 6 N PARKS 35.35N 111.95W
12/24/2021 E6.0 INCH COCONINO AZ PUBLIC
FACEBOOK REPORT WITH SNOW ONGOING AT TIME OF
REPORT.
&&
NLPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
1259 PM MST FRI DEC 24 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1230 PM SNOW PARKS 35.26N 111.95W
12/24/2021 E7.0 INCH COCONINO AZ PUBLIC
FACEBOOK REPORT WITH PHOTO. LIGHT SNOW
SHOWERS AT TIME OF REPORT.
&&
NLPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
104 PM MST FRI DEC 24 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0100 PM SNOW SUNRISE PARK 33.97N 109.56W
12/24/2021 E9.0 INCH APACHE AZ CO-OP OBSERVER
ESTIMATED STORM TOTAL SO FAR WITH SNOW
ONGOING AT TIME OF REPORT.
&&
NLPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
224 PM MST FRI DEC 24 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0214 PM SNOW 1 E FOREST LAKES 34.34N 110.79W
12/24/2021 M10.0 INCH COCONINO AZ TRAINED SPOTTER
AS OF 1414 MST - 10 INCHES WITH SNOW
ONGOING. CORRECT PREVIOUS REPORT. AS OF 10
AM - 0.78 INCHES RAIN OVERNIGHT 12/23 THAT
TRANSITIONED TO SNOW AROUND 0500 MST. 8
INCHES OF SNOW SO FAR. SNOW ONGOING.
&&
NLPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
259 PM MST FRI DEC 24 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0230 PM SNOW 1 NNW PINETOP-LAKESIDE 34.16N 109.97W
12/24/2021 M2.2 INCH NAVAJO AZ TRAINED SPOTTER
CORRECTS PREVIOUS SNOW REPORT FROM 1 NNW
PINETOP-LAKESIDE. SPOTTER N297. STILL LIGHT
SNOWFALL AFTER TIME OF REPORT.
&&
NLThe national radar mosaic for the moment the first event began.
1 ice storm. Local standard time, as filed.
Rim ice coated NWR transmission equipment on Mt Elden just northeast of Flagstaff. This caused transition problems to at least one NWR station (Mt Ord near Payson).
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2021Every state in 2021This day in weather historyWarnings in Arizona, December 2021
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: 990251.