A shortwave trough and associated cold front moved across northern Arizona overnight and during the morning with heavy snow in northern Apache County.
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.
A shortwave trough and associated cold front moved across northern Arizona overnight and during the morning with heavy snow in northern Apache County.
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 Feb 15, 9:04 PM MST, 56 minutes earlier.
Area Forecast Discussion National Weather Service Flagstaff AZ 904 PM MST Mon Feb 15 2021 .SYNOPSIS...Gusty southwest winds will continue overnight, shifting to westerly and slightly decreasing Tuesday. Rain and snow showers develop tonight and move southeast into Tuesday evening. A Winter Weather Advisory is in effect for northern Navajo county and most of of Apache county from later tonight through Tuesday. Scattered snow showers will persist Wednesday, before warmer and drier weather arrives for the end of the week. && .UPDATE...Mostly dry conditions continue this evening, though a few very light radar echoes are just beginning to show up in northeastern Arizona in advance of our next weather system. We still expect showers to develop across the Utah border in the next couple of hours and spread south overnight. Our current forecast trends are on track with the latest guidance this evening and no major updates are planned. Winter Weather Advisories are in effect tonight for much of northeastern Arizona. && .PREV DISCUSSION /235 PM MST/...A low-amplitude trough entering the Pacific Northwest will move southeast through the Great Basin tonight and into eastern Arizona tomorrow. Cooler air aloft, upslope flow and a cold frontal passage Tuesday will provide enough forcing for another round of rain and snow showers. This storm does not have the amplitude or trajectory of the last storm, so QPF amounts will decrease and chances of thunderstorms will be minimized. The best combination of frontal forcing and upslope flow occurs over the Chuska Mtns late tonight and early Tuesday, shifting south through Apache county during the day and into Tuesday evening. A Winter Weather Advisory has been issued for Apache county and the Black Mesa. Windy conditons will continue to develop this afternoon, lasting overnight and continuing over the eastern zones Tuesday. Wind speeds should stay under criteria, although a few locations north of the Mogollon Rim may have occasional gusts over 40 mph. Some light instability showers will persist Wednesday, as cold, northwest flow aloft persists. The remainder of the week will feature dry and warmer weather, with a potential dry cold frontal passage over the weekend. && .AVIATION...For the 06Z package...A trough of low pressure will move from northwest to southeast across northern Arizona tonight and Tuesday. Rain and snow showers will produce MVFR and IFR conditions. Expect gradual clearing west to east Tuesday afternoon with lingering showers over eastern Arizona though early Wednesday. Southwest winds at 10-20 kts through the overnight period. Areas of low level wind shear are likely at some high country terminals. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Southwest winds to remain breezy tonight north of the Mogollon Rim. Winds shift to become northwesterly and remain breezy on Tuesday. Rain and snow showers will develop north to south tonight and continue into late Tuesday. Showers will linger Wednesday morning for the eastern zones. Thursday through Saturday...Dry conditions are forecast areawide for Thursday through Saturday. Below normal temperatures through Thursday warm on Friday. Southwest breezes return Saturday afternoon. && .FGZ WATCHES/WARNINGS/ADVISORIES...Winter Weather Advisory until 6 PM MST Tuesday FOR AZZ010-011-014-039. Winter Weather Advisory from 5 AM to 8 PM MST Tuesday FOR AZZ017. && PUBLIC...MCT/Peterson AVIATION...MAS FIRE WEATHER...ET For Northern Arizona weather information visit weather.gov/flagstaff
The national radar mosaic for the moment the first event began.
1 heavy snow. Local standard time, as filed.
Heavy snow fell across northern Apache County with Tsaile reporting 9.5 inches by 1030 AM and Saint Michaels had 8.6 inches.
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, February 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: 948441.