A strong winter storm dropped heavy amounts of snow across northern Arizona. Over two and a half feet of fresh snow fell over the most snow prone area of the Mogollon Rim in Forest Lakes.
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.
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 winter storm dropped heavy amounts of snow across northern Arizona. Over two and a half feet of fresh snow fell over the most snow prone area of the Mogollon Rim in Forest Lakes.
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, 3:34 AM MST, 2 hours 26 minutes earlier.
AREA FORECAST DISCUSSION...RETRANSMITTED NATIONAL WEATHER SERVICE FLAGSTAFF AZ 334 AM MST MON DEC 12 2011 .SYNOPSIS...A LOW PRESSURE SYSTEM WILL MOVE ACROSS THE SOUTHWESTERN STATES DURING THE FIRST HALF OF THE WEEK. ACCUMULATING MOUNTAIN SNOW AND LOW ELEVATION RAIN ARE LIKELY FROM LATE TODAY THROUGH WEDNESDAY MORNING WITH THE HEAVIEST AMOUNTS FROM THE MOGOLLON RIM SOUTHWARD...INCLUDING THE WHITE MOUNTAINS AND THE YAVAPAI COUNTY MOUNTAINS. && .DISCUSSION...THE NEXT AREA OF LOW PRESSURE SET TO AFFECT OUR REGION IS TAKING SHAPE OFF THE SOUTHERN CALIFORNIA COAST. THERE IS STILL A PROBLEM OF PREDICTABILITY AS THE FIRST PART OF THE LOW IS SET TO MOVE EASTWARD AND BEGIN AFFECTING NORTHERN ARIZONA LATE THIS AFTERNOON...HOWEVER THERE IS A SECOND VORT./JET STREAK COMING DOWN THE BACK SIDE OF THE LOW...NEAR THE NORTHERN CALIFORNIA/OREGON BORDER (09:15Z). THIS UPSTREAM FEATURE COULD POSSIBLY DIG THE PARENT LOW OFF THE SOUTHERN CALIFORNIA COAST FARTHER TO OUR SOUTH. TWO THINGS COULD COME OF THIS (1) THIS SECONDARY VORT WILL HELP TO DEEPEN THE LOW AND INTENSIFY IT AS IT LIFTS NORTHEAST TOWARD N. AZ...HELPING TO ADDED TO THE SNOWFALL AMOUNTS OR (2) THIS SECONDARY VORT. COULD DEEPEN AND INTENSIFY THE THE PARENT LOW OFF THE CALIFORNIA COAST AND DIG THE LOW FARTHER SOUTH AND AWAY FROM N. AZ CAUSING LESSER SNOWFALL AND PRECIPITATION AMOUNTS. FOR NOW WE WILL DEAL WITH SCENARIO #1...AND REPLACE THE WINTER STORM WATCH WITH A WINTER STORM WARNING AS OUR CONFIDENCE IN GETTING WARNING SNOWFALL AMOUNTS INCREASES. THE WINTER STORM WARNING IS FOR SNOWFALL AMOUNTS FROM 12"-24"... THE EASTERN MOGOLLON RIM...NORTHERN GILA COUNTY MOUNTAINS ABOVE 5500' THE WHITE MOUNTAINS ABOVE 6500' THE WESTERN MOGOLLON RIM...OAK CREEK AND SYCAMORE CANYONS...AND THE YAVAPAI COUNTY MOUNTAINS ABOVE 5500' THE WINTER WEATHER ADVISORY IS FOR SNOWFALL AMOUNTS FROM 6"-12"... THE GRAND CANYON COUNTRY...KAIBAB PLATEAU...AND COCONINO PLATEAU KEEP IN MIND...IF THIS SYSTEM DIGS AND GOES FARTHER SOUTH...THEN THE SNOWFALL AMOUNTS MENTION IN THE WINTER STORM WARNING AND THE THE SNOW ADVISORY MAY BE LESS... AS FOR TUESDAY...THE SYSTEM IS FORECAST TO LIFT NORTHEAST TOWARD ARIZONA AND AS IT DOES THE NORTHEAST ZONES...THE CHUSKA MOUNTAINS AND PORTIONS OF NORTHEAST PLATEAUS...THE BLACK MESA AREA MAY NEED A SNOW ADVISORY. THIS SYSTEM HAS A LOT OF THINGS GOING FOR IT...COLD ENOUGH TEMPERATURES TO PRODUCE GOOD ICE MICROPHYSICS AND SNOWFALL EFFICIENCIES...WEAK TO MODERATE UPSLOPE COMPONENT...MODERATE SYNOPTIC LIFT OVER A TWO DAY PERIOD. BASICALLY THIS STORM HAS THE INGREDIENTS TO PRODUCE A GOOD AMOUNT OF SNOW OVER A TWO-DAY PERIOD AND CAN PRODUCE SIGNIFICANT TRAVEL IMPACTS AND AFFECT COMMERCE. BY WEDNESDAY THIS STORM WILL HAVE LIFTED TO THE NORTHEAST INTO COLORADO AND NEW MEXICO...WITH SNOW AND RAIN ON THE DECREASE OVER ARIZONA. NORTHERN ARIZONA OVERALL WILL REMAIN IN A LARGE SCALE TROUGH PATTERN THURSDAY THROUGH FRIDAY...HOWEVER N. AZ WILL REMAIN DRY WITH SLIGHTLY BELOW NORMAL HIGH TEMPERATURES. BY LATE FRIDAY INTO SATURDAY ANOTHER STORM SYSTEM IS FORECAST TO APPROACH N. AZ WITH INCREASING CHC'C FOR SHOWERS ONCE AGAIN...STILL TOO EARLY TO CONCLUDE PRECIP AMOUNTS FROM THIS PATTERN. && .AVIATION...FOR THE 12Z PACKAGE...EXPECT DETERIORATING CONDITIONS THROUGH THE DAY AS A STRONG STORM SYSTEM MOVES OVER ARIZONA. LOWERING CLOUDS AND WIDESPREAD PRECIPITATION WILL LEAD TO WIDESPREAD MVFR/IFR CONDITIONS IN RAIN AND SNOW SHOWERS BY 21Z...CONTINUING THROUGH TUESDAY. THE SNOW LEVEL WILL GENERALLY RANGE FROM 5500 TO 6500 FT MSL. AVIATION DISCUSSION NOT UPDATED FOR AMENDMENTS. && .FGZ WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING FROM NOON MST TODAY THROUGH 5 AM WEDNESDAY ABOVE 6500 FEET FOR AZZ017. WINTER STORM WARNING FROM NOON MST TODAY THROUGH 5 AM WEDNESDAY ABOVE 5500 FEET FOR AZZ016-018. WINTER STORM WARNING FROM 5 PM THIS AFTERNOON TO 5 AM MST WEDNESDAY FOR AZZ008-015-038. WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 5 AM MST WEDNESDAY FOR AZZ004-006-007. && PUBLIC...............TC AVIATION.............DM FOR NORTHERN ARIZONA WEATHER INFORMATION VISIT WEATHER.GOV/FLAGSTAFF.
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE FLAGSTAFF AZ 455 AM MST MON DEC 12 2011 AZZ004>018-037>040-130930- KAIBAB PLATEAU-MARBLE AND GLEN CANYONS-GRAND CANYON COUNTRY- COCONINO PLATEAU-YAVAPAI COUNTY MOUNTAINS- NORTHEAST PLATEAUS AND MESAS HWY 264 NORTHWARD-CHINLE VALLEY- CHUSKA MOUNTAINS AND DEFIANCE PLATEAU- LITTLE COLORADO RIVER VALLEY IN COCONINO COUNTY- LITTLE COLORADO RIVER VALLEY IN NAVAJO COUNTY- LITTLE COLORADO RIVER VALLEY IN APACHE COUNTY- WESTERN MOGOLLON RIM-EASTERN MOGOLLON RIM-WHITE MOUNTAINS- NORTHERN GILA COUNTY-YAVAPAI COUNTY VALLEYS AND BASINS- OAK CREEK AND SYCAMORE CANYONS-BLACK MESA AREA- NORTHEAST PLATEAUS AND MESAS SOUTH OF HWY 264- 455 AM MST MON DEC 12 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EAST CENTRAL ARIZONA...NORTH CENTRAL ARIZONA...NORTHEAST ARIZONA AND WEST CENTRAL ARIZONA. .DAY ONE...TODAY AND TONIGHT A POTENT WINTER STORM WILL BRING RAIN AND SNOW TO NORTHERN ARIZONA STARTING TODAY. A WINTER STORM WARNING IS IN EFFECT FROM MONDAY AFTERNOON THROUGH EARLY WEDNESDAY MORNING FOR THE WHITE MOUNTAINS...THE ENTIRE MOGOLLON RIM...YAVAPAI COUNTY MOUNTAINS AND NORTHERN GILA COUNTY. A WINTER WEATHER ADVISORY IS IN EFFECT FOR THE GRAND CANYON COUNTRY...COCONINO AND KAIBAB PLATEAUS FOR LESSER SNOWFALL AMOUNTS. IN THE WHITE MOUNTAINS...SNOW LEVELS ARE FORECAST AT 6500 FEET WITH WIDESPREAD 1 TO 2 FEET OF NEW SNOW...AND UP TO 30 INCHES AT THE HIGHEST ELEVATIONS. THE REST OF THE MOGOLLON RIM...NORTHERN GILA AND YAVAPAI COUNTIES SHOULD SEE WIDESPREAD NEW SNOW ACCUMULATIONS OF 8 TO 14 INCHES ABOVE 5500 FEET...WITH UP TO 2 FEET FOR AREAS ABOVE 7500 FEET. THE COCONINO AND KAIBAB PLATEAU...AND THE GRAND CANYON COUNTRY SHOULD SEE 4 TO 10 INCHES ABOVE 5500 FEET...WITH UP TO 14 INCHES ABOVE 7500 FEET. PEOPLE WITH TRAVEL OR OUTDOOR PLANS SHOULD SHOULD PREPARE FOR WINTER WEATHER. GATHER YOUR EMERGENCY TRAVEL SUPPLIES NOW AND PUT THEM IN YOUR CAR IF YOU PLAN TO TRAVEL. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY THE WINTER STORM IS EXPECTED TO LAST THROUGH WEDNESDAY MORNING...BEFORE MOVING EAST OF THE REGION WEDNESDAY AFTERNOON. PRECIPITATION IS EXPECTED TO DECREASE WEDNESDAY AFTERNOON WITH IMPROVING CONDITIONS. ANOTHER WEATHER SYSTEM WITH INCREASED CHANCES OF SNOW AND RAIN SHOWERS IS EXPECTED AS EARLY AS FRIDAY MORNING IN THE WEST SPREADING EAST DURING THE DAY AND LASTING THROUGH THE DAY SATURDAY.
The national radar mosaic for the moment the first event began.
5 heavy snow. Local standard time, as filed.
Flagstaff Airport received 17.6 inches of new snow, Kachina Village17.0, Bellemont 13.5, 13.0 inches in northeast Flagstaff, Munds Park 13, 11 inches south of Williams, and 9 inches in Parks.
Fifteen inches of snow fell in Pine.
Alpine received 22 inches of snow and McNary received 7 inches of snow.
Heavy snow fell along the Eastern Mogollon Rim. Forest Lakes reported 33 inches of snow over a two day period.
Nine inches of snow fell 5 miles west of Prescott.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2011Every state in 2011This day in weather historyWarnings in Arizona, December 2011
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: 358777, 358778, 358772, 358774, 358779.