A late season winter storm impacted Southeast Arizona on March 18th and March 19th producing snow in the mountains and in some of the lower elevations as well.
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 TWC wrote it up.
A late season winter storm impacted Southeast Arizona on March 18th and March 19th producing snow in the mountains and in some of the lower elevations as well.
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 Tucson, AZ wrote its last area forecast discussion before the first event at Mar 18, 2:25 AM MST, 2 hours 35 minutes earlier.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
225 AM MST SUN MAR 18 2012
.SYNOPSIS...WINDY WITH MUCH COLDER TEMPERATURES AND PERIODS OF
SHOWERS TODAY INTO MONDAY. EXPECT SIGNIFICANT SNOW ACCUMULATIONS FOR
THE MOUNTAINS WITH SNOW LEVELS LOWERING NEAR VALLEY FLOORS SUNDAY
NIGHT INTO EARLY MONDAY MORNING. DRY CONDITIONS WILL RETURN THE
SECOND HALF OF THE WEEK WITH A STRONG WARMING TREND.
&&
.DISCUSSION...FRONT PUSHING THROUGH YUMA COUNTY EARLY THIS MORNING
AND INTO WESTERN PIMA COUNTY WITH SHOWERS SPREADING IN WITH IT FROM
THE WEST. INITIAL HIGH SNOW LEVELS WILL START TO CRASH BEHIND THE
FRONT WITH THE COLD AIR. FRONTAL BOUNDARY TO TUCSON BETWEEN 8 AND 10
AM OR SO. THAT WILL BE OUR HIGH TEMPERATURE FOR THE DAY WITH
TEMPERATURES FALLING BEHIND THE FRONT. RATHER WINDY AHEAD OF THE
FRONT...SO EASTERN AREAS WILL DEFINITELY NEED A WIND ADVISORY TODAY
BEFORE THE FRONT SWEEPS THROUGH FAR EASTERN AREAS THIS AFTERNOON.
THESE LOCATIONS WILL ALSO HAVE MORE TIME FOR NORMAL DAYTIME HEATING
BEFORE THE FRONT ARRIVES...SO EASTERN AREAS WILL IN SOME CASES BE
MUCH WARMER TODAY THAN WESTERN AREAS. SNOW LEVELS AROUND 7-8K FT NOW
DOWN TO 4.5 TO 5K FT OR SO MID MORNING...AS LOW AS 4K FT LATER THIS
AFTERNOON AND DOWN TO VALLEY FLOORS LATER TONIGHT INTO MONDAY
MORNING. WINTER STORM WARNING ABOVE 5000 FEET TODAY AND THEN ABOVE
3000 FEET TONIGHT AND MONDAY WITH SNOW LEVELS AS LOW AS 2500 FEET OR
SO.
SHOWERS FOR A COUPLE HOURS AFTER FRONTAL BOUNDARY BUT COULD SEE A
BREAK BY MID AFTERNOON IN MANY LOCATIONS BEFORE ANOTHER SHOT OF
ENERGY REINFORCES THE BACK SIDE OF THE TROUGH TONIGHT AND
MONDAY...ESPECIALLY FROM TUCSON EASTWARD.
STORM TOTAL SNOWFALL IN SOME MOUNTAIN LOCATIONS WILL RANGE FROM
12-24 INCHES...WITH THE HIGHEST TOTALS ACROSS THE WHITE MOUNTAINS...
THE PINALENO MOUNTAINS INCLUDING MT GRAHAM...AND AS FAR SOUTHWEST AS
THE CATALINA/RINCON MOUNTAINS NEAR TUCSON. LOWER ELEVATION SNOW
ACCUMULATIONS OF 3-8 INCHES FOR ORACLE...CLIFTON...DUNCAN AND
BISBEE. 2-4 INCHES FOR BENSON...WILLCOX AND TOMBSTONE. 1-3 INCHES
FOR SIERRA VISTA...DOUGLAS AND NOGALES AS WELL AS THE TUCSON
FOOTHILLS.
STRONG RIDGE BUILDS IN WEDNESDAY WITH DRY CONDITIONS AND A STRONG
WARMING TREND THE SECOND HALF OF THE WEEK. BACK INTO THE 80S IN MOST
LOCATIONS BY THURSDAY OR FRIDAY.
&&
.AVIATION...SURFACE COLD FRONT ACROSS WESTERN DESERTS WILL REACH A
KTUS TO KOLS LINE BY 14Z THIS MORNING WITH WIDESPREAD -SHRA AND
HIGHER TERRAIN -SHSN. OVC SKIES GENERALLY 4-8KFT AGL WITH AREAS OF
MVFR CIGS/VSBYS AND OCCASIONAL IFR CIGS/VSBYS POSSIBLE AS COLD FRONT
PASSES THIS MORNING. VSBYS COULD DROP TO 2-3SM IN MODERATE/HEAVIER
SHOWERS. THERE WILL ALSO BE A SLIGHT CHANCE FOR
THUNDERSTORMS...ESPECIALLY AS FRONT PASSES...BUT WILL NOT INCLUDE IN
TAFS. POST FRONTAL PASSAGE...EXPECT CONTINUED CLOUDY CONDITIONS WITH
CLOUD DECKS GENERALLY 4-8K FT AGL. OCCASIONAL MVFR CONDITIONS WILL
BE POSSIBLE AS SCT -SHRA THIS AFTERNOON WITH IFR CONDITIONS IN THE
HIGHER TERRAIN AND -SHSN. -SHRA SHOULD END WEST TO EAST LATE THIS
AFTERNOON/EARLY EVENING...BUT CANNOT RULE OUT ISOLD -SHRA. SHSN WILL
CONTINUE ACROSS THE WHITE MOUNTAINS IN EAST CENTRAL ARIZONA THROUGH
MONDAY MORNING. HOWEVER...ISOLD SHSN AS LOW AS 3500 FEET WILL BE
POSSIBLE TONIGHT INTO EARLY TOMORROW MORNING. EXPECT STRONG
SOUTHWEST SFC WINDS 25 TO 35 KTS WITH GUSTS UP TO 50 KTS EAST OF A
KTUS/KSAD LINE WITH 20 TO 30 KTS AND GUSTS OF 40 KTS WEST OF THIS
LINE. WINDS WILL BEGIN TO FINALLY SUBSIDE LATE TONIGHT. AVIATION
DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...INCREASING MOISTURE...WIDESPREAD SHOWERS AND HIGHER
TERRAIN SNOW SHOWERS AND WELL BELOW NORMAL TEMPERATURES WILL ALLOW
FOR NO FIRE WEATHER CONCERNS THIS WEEKEND. HOWEVER...STRONG
SOUTHWEST WINDS WILL CONTINUE TODAY. VALLEY RAIN AND MOUNTAIN SNOW
WILL CONTINUE INTO MONDAY. DRY CONDITIONS WILL RETURN TUESDAY
THROUGH SATURDAY ALONG WITH A STRONG WARMING TREND.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 9 AM UNTIL 8 PM MST TODAY FOR AZZ503-507>515.
WINTER STORM WARNING FROM 5 AM TODAY UNTIL 11 AM MST MONDAY FOR
FOR AZZ510>514.
WINTER STORM WARNING FROM 5 PM TODAY UNTIL 11 AM MST MONDAY FOR
FOR AZZ503-504-506>509-515 ABOVE 3000 FEET.
&&
WEATHER.GOV/TUCSONHAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE TUCSON AZ 405 AM MST SUN MAR 18 2012 AZZ501>515-182315- WESTERN PIMA COUNTY-TOHONO O'ODHAM NATION- UPPER SANTA CRUZ RIVER VALLEY/ALTAR VALLEY-TUCSON METRO AREA- SOUTH CENTRAL PINAL COUNTY-SOUTHEAST PINAL COUNTY- UPPER SAN PEDRO RIVER VALLEY- EASTERN COCHISE COUNTY BELOW 5000 FEET-UPPER GILA RIVER VALLEY- WHITE MOUNTAINS OF GRAHAM AND GREENLEE COUNTIES- GALIURO AND PINALENO MOUNTAINS-CHIRICAHUA MOUNTAINS- DRAGOON AND MULE AND HUACHUCA AND SANTA RITA MOUNTAINS- CATALINA AND RINCON MOUNTAINS-BABOQUIVARI MOUNTAINS- 405 AM MST SUN MAR 18 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST ARIZONA. .DAY ONE...TODAY AND TONIGHT A LARGE STORM SYSTEM WILL IMPACT THE REGION TODAY INTO MONDAY. A WINTER STORM WARNING IS IN EFFECT ABOVE 5000 FEET AND ABOVE 3000 FEET TONIGHT INTO MONDAY MORNING. SNOW LEVELS WILL FALL AS LOW AS 2500 FEET EARLY MONDAY MORNING. STRONG WINDS ARE EXPECTED AHEAD OF THE COLD FRONT TODAY AS WELL WITH BLOWING DUST POSSIBLE. THUS...A WIND ADVISORY IS IN EFFECT GENERALLY EAST AND SOUTH OF TUCSON. PLEASE SEE SPECIFIC WATCH...WARNING AND ADVISORY PRODUCTS FOR ADDITIONAL INFORMATION. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY A LARGE STORM SYSTEM WILL CONTINUE TO IMPACT THE REGION MONDAY AND MONDAY NIGHT. A WINTER STORM WARNING IS IN EFFECT ABOVE 3000 FEET MONDAY MORNING. SNOW LEVELS WILL FALL AS LOW AS 2500 FEET MONDAY MORNING BEFORE LIFTING AGAIN TO AROUND 4000 FEET. PLEASE SEE SPECIFIC WATCH...WARNING AND ADVISORY PRODUCTS FOR ADDITIONAL INFORMATION. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. WEATHER.GOV/TUCSON
The national radar mosaic for the moment the first event began.
4 heavy snow, 1 high wind. Local standard time, as filed.
About 6 inches of snow occurred on Kitt Peak on the Baboquivari Mountains.
About 3 to 4 inches of snow occurred at Oracle in Southeast Pinal County.
About 1 foot of snow occurred at Hannagan Meadow in Northern Greenlee County.
Two to four inches of snow occurred in elevations from about 3500 to 4000 feet in Graham County.
Sustained winds of 40 MPH with gusts to 55 MPH occurred at Douglas-Bisbee airport.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2012Every state in 2012This day in weather historyWarnings in Arizona, March 2012
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: 361327, 361330, 361329, 364266, 361524.