A strong cold front brought high winds to parts of northern Arizona on December 12 and 13.
Every event with a place to put it; 2 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.
A strong cold front brought high winds to parts of northern Arizona on December 12 and 13.
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 12, 2:02 PM MST, 3 hours 21 minutes earlier.
Area Forecast Discussion National Weather Service Flagstaff AZ 202 PM MST Sat Dec 12 2020 .SYNOPSIS...Snow showers will continue along and north of the Mogollon Rim through the evening. The main impacts will be periods of gusty winds with the most impactful snow along the Kaibab Plateau and in the Chuska Mountains. Another cold but drier system is forecast on Monday. Look for moderating daytime temperatures by Wednesday and Thursday. && .DISCUSSION...Light snow showers have been reported in many locations this afternoon including Grand Canyon National Park, Bellemont/Flagstaff, and Navajo Mountain to name a few. The cold front is dipping it's way into the state and we can expect the heaviest precipitation to be along the frontal passage this afternoon into the early evening. This will be a quick moving front with brief moderate to heavy snow in a few locations where heavier bands set up. Accumulations are unchanged with the afternoon update. The Winter Weather Advisory remains in effect until 11 pm for areas above 7500 ft near the Chuska Mountains. In addition to the snowfall, afternoon gusts have verified with areas in the Wind Advisory gusting 40-50 mph. The Wind Advisory will continue through 5 pm. Be aware that poor visibility and blowing snow may be possible in the northeast where a few bands of snow showers are ongoing this afternoon. If you have to travel, slow down and be prepared for winter weather driving conditions. Precipitation chances will quickly end west to east this evening. As the front moves out, winds will shift to the northwest behind it and then eventually become northeasterly Sunday morning. Expect very gusty conditions along and south of the high terrain Sunday morning. Winds will be strongest in the early morning and then steadily decrease through the morning and afternoon. In addition, expect very chilly highs on Sunday along and north of the Mogollon Rim. The coldest temperatures will be in the northeast near the Four Corners where many places may hover around freezing for highs. With very dry air filtering in as well, conditions will be just plain bitterly cold. Another much drier weather system is forecast to move through on Monday brining another round of breezy west to southwest winds. There is a slight chance for showers mainly on the Kaibab Plateau. A few flurries will be possible at times for areas in the far north. Temperatures Monday will be warmer than Sunday but remain cool as this system brings in a reinforcing shot of cold air. Temperatures on Tuesday will drop back down a few degrees as well. For the rest of the week, we still expect ridging to build back in with a gradual warm up in temperatures and a return to much quieter mild weather. Next weekend still looks to be a return to more unsettled weather with the potential for another system on Friday. && .AVIATION...For the 00Z package...A cold front will bring areas of snow along/east of a line from KGCN-KFLG-KPAN during the evening. Widespread MVFR and areas IFR are anticipated with this precipitation. By 01Z...along the Utah border winds will shift to north to northeast at 10-20 kt with VFR conditions developing which will then spread southward across all of northern Arizona by 07Z. After 07Z...VFR conditions area wide with locally gusty northeasterly winds continuing. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Look for dry conditions on Sunday with locally gusty northeasterly Winds. For Monday, yet another weak disturbance will brush Arizona delivering a slight chance of snow showers from the Mogollon Rim and White Mountains northward along with gusty west to southwest winds. Tuesday through Thursday...It will be cold and dry through the period. Locally gusty northerly winds on Tuesday will become light on Wednesday but increase again from the southwest direction on Thursday as yet another weather disturbance approaches. && .FGZ WATCHES/WARNINGS/ADVISORIES...Wind Advisory until 5 PM MST this afternoon FOR AZZ012-013-015- 016. Winter Weather Advisory until 11 PM MST this evening FOR AZZ011. Wind Advisory until 8 PM MST this evening FOR AZZ014-017. && PUBLIC...ET AVIATION...McCollum FIRE WEATHER...McCollum For Northern Arizona weather information visit weather.gov/flagstaff
The national radar mosaic for the moment the first event began.
2 high wind. Local standard time, as filed.
The ADOT wind sensor at Jackrabbit (270 mile on I-40) had a peak wind gust of 61 MPH at 523 PM.
The NWS Davis weather station at Snowbowl (10,767 feet) measured wind gusts of 58 MPH or higher from around 1130 PM to around 430 AM. The peak wind gust of 73 MPH was measured at 1235 AM.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2020Every state in 2020This day in weather historyWarnings in Arizona, December 2020
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: 932223, 932227.