A low pressure system slowly moving across the Great Basin produced high winds in east-central Arizona.
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 low pressure system slowly moving across the Great Basin produced high winds in east-central Arizona.
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 Apr 26, 9:25 AM MST, 5 hours 30 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE FLAGSTAFF AZ 925 AM MST TUE APR 26 2011 .SYNOPSIS...A COLD FRONT WILL BRING STRONG WESTERLY WINDS TO NORTHERN ARIZONA...A SLIGHT CHANCE OF SHOWERS TO THE FOUR CORNERS AREA...AND SLIGHTLY COOLER TEMPERATURES TODAY. WARMER TEMPERATURES AND LESS WIND ARE EXPECTED FOR THE LATTER HALF OF THE WEEK. BREEZY AND COOLER CONDITIONS CAN BE EXPECTED FOR THE WEEKEND. && .DISCUSSION...STRONG MID-LEVEL FLOW BEHIND A COLD FRONT WHICH PASSED THROUGH THE FOUR CORNERS AREA THIS MORNING WILL BRING STRONG WEST TO NORTHWEST WINDS ACROSS NORTHEAST ARIZONA TODAY...AS WELL AS A FEW LINGERING SHOWERS NEAR THE NM BORDER IN NORTHEAST AZ. A WIND ADVISORY REMAINS IN EFFECT UNTIL THIS EVENING IN PORTIONS OF NORTHEAST AZ. WINDS WILL WEAKEN AND SHIFT TO NORTHEASTERLY OVERNIGHT WITH ALL SHOWER ACTIVITY ENDING BY LATE AFTERNOON. CURRENT FORECAST PACKAGE DEPICTS THE SITUATION WELL AND NO UPDATES ARE PLANNED THIS MORNING. && .PREV DISCUSSION/315 AM MST/...SFC COLD FRONT WAS PUSHING SOUTHWARD ACROSS THE GREAT BASIN EARLY THIS MORNING WITH SOME SHOWER ACTIVITY NOTED ALONG THE UT/AZ BORDER. WINDS HAVE REMAINED BREEZY OVERNIGHT AND SOME LOCATIONS ARE ALREADY HITTING WIND ADVISORY THRESHOLDS. HAVE EXPANDED THE WIND ADVISORY TO INCLUDE THE MOGOLLON RIM AND THE NORTHERN ZONES...IN ADDITION TO THE LITTLE COLORADO RIVER VALLEY ZONES ALREADY IN THE ADVISORY. WINDS SHOULD PEAK BY LATE MORNING OR EARLY AFTERNOON IN THE WESTERN ZONES AND BY LATE AFTERNOON IN THE EASTERN ZONES. LOW POPS REMAIN IN THE FOUR CORNERS AND UT/AZ BORDER REGIONS THIS MORNING...WITH DIMINISHING CHANCES BY THIS AFTERNOON. WEDNESDAY THROUGH FRIDAY...MIN TEMPS AT OR BELOW 32 DEGREES ARE FCST FOR MUCH OF THE AREA ALONG AND NORTH OF THE MOGOLLON RIM WEDNESDAY MORNING. SIGNIFICANT WARMING IS THEN EXPECTED WEDNESDAY AFTERNOON THROUGH FRIDAY AS A FLAT RIDGE OF HIGH PRESSURE MOVES ACROSS THE DESERT SOUTHWEST. FOR THE WEEKEND...OPERATIONAL MODEL DIFFERENCES CONTINUE. THE ECMWF STILL SHOWS A MUCH COLDER AND SHARPER TROUGH DROPPING SOUTHWARD INTO AZ ON SATURDAY COMPARED TO THE GFS WHICH SHOWS A MORE BROAD AND FASTER TROUGH. WILL KEEP A SLIGHT CHANCE OF SHOWERS AND SLIGHTLY COOLER TEMPS IN THE FCST FOR THE WEEKEND. && .AVIATION...FOR THE 18Z PACKAGE...A COLD FRONT WILL BRING A SLIGHT CHANCE FOR SHOWERS TO THE FOUR CORNERS AREA INTO THIS AFTERNOON. OTHERWISE...VFR CONDITIONS WILL PERSIST. GUSTY WEST WINDS ARE ANTICIPATED OVER MUCH OF THE AREA...ESPECIALLY FOR EAST-CENTRAL ARIZONA WHERE WINDS OF 20-25KT GUSTING TO 35-40KTS WILL BE COMMON THROUGH 02Z. AVIATION DISCUSSION NOT UPDATED FOR AMENDMENTS. && .FIRE WEATHER... A COLD FRONT WILL MOVE ACROSS NORTHERN ARIZONA EARLY TODAY. STRONG WEST TO NORTHWEST WINDS WILL DEVELOP AND CONTINUE INTO THIS EVENING. THESE WINDS COUPLED WITH A DRY SURFACE LAYER WILL RESULT IN CRITICAL FIRE WEATHER CONDITIONS FOR A LARGE PORTION OF EAST-CENTRAL AND NORTHEAST AZ FOR MUCH OF THE DAY. BREEZY CONDITIONS UNDER DRY WESTERLY FLOW WILL PERSIST FOR WEDNESDAY. THURSDAY THROUGH SATURDAY...CONTINUED WARM AND DRY CONDITIONS WITH GUSTY SPRINGTIME WINDS ARE LIKELY THROUGH THE PERIOD. && .FGZ WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING UNTIL 700 PM MST FOR FIRE WEATHER ZONES AZZ111>114-116-117-140. WIND ADVISORY IN EFFECT UNTIL 500 PM MST FOR AZZ009-012-015-016-039. WIND ADVISORY IN EFFECT FROM 1100 AM TO 700 PM MST FOR AZZ-010-011-013-014-017-040. && PUBLIC...............DJO/DB AVIATION/FIRE WX.....KD/MAS FOR NORTHERN ARIZONA WEATHER INFORMATION VISIT WEATHER.GOV/FLAGSTAFF.
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE FLAGSTAFF AZ 500 AM MST TUE APR 26 2011 AZZ004>018-037>040-270700- WESTERN MOGOLLON RIM-GRAND CANYON COUNTRY-YAVAPAI COUNTY MOUNTAINS- YAVAPAI COUNTY VALLEYS AND BASINS-OAK CREEK AND SYCAMORE CANYONS- MARBLE AND GLEN CANYONS-KAIBAB PLATEAU-COCONINO PLATEAU- NORTHEAST PLATEAU AND MESAS HWY 264 NORTHWARD- NORTHEAST PLATEAU AND MESAS SOUTH OF HWY 264- CHINLE VALLEY-CHUSKA MOUNTAINS AND DEFIANCE PLATEAU- BLACK MESA AREA-LITTLE COLORADO RIVER VALLEY IN COCONINO COUNTY- LITTLE COLORADO RIVER VALLEY IN NAVAJO COUNTY- LITTLE COLORADO RIVER VALLEY IN APACHE COUNTY- EASTERN MOGOLLON RIM-WHITE MOUNTAINS-NORTHERN GILA COUNTY- 500 AM MST TUE APR 26 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR APACHE...COCONINO...NORTHERN GILA...NAVAJO...AND YAVAPAI COUNTIES IN NORTHERN ARIZONA. .DAY ONE...TODAY A COLD FRONT WILL BRING STRONG WINDS TO NORTHERN ARIZONA TODAY. WINDS WILL INCREASE DURING THE DAY BECOMING WEST TO NORTHWEST AT 20 TO 35 MPH WITH GUSTS OF 40 TO 50 MPH ACROSS APACHE COUNTY...NAVAJO COUNTY...AND EASTERN COCONINO COUNTY. A WIND ADVISORY IS IN EFFECT FOR THESE AREAS. SEE PRODUCT PHXNPWFGZ FOR DETAILS. LOW AFTERNOON RELATIVE HUMIDITIES WILL ACCOMPANY THE FRONT AND COMBINED WITH THE STRONG WINDS WILL RESULT IN CRITICAL FIRE WEATHER CONDITIONS. A RED FLAG WARNING HAS BEEN ISSUED FOR PORTIONS OF NORTHERN ARIZONA. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
The national radar mosaic for the moment the first event began.
1 high wind. Local standard time, as filed.
The ASOS at St Johns Airport recorded a peak wind gust of 51 Knots (59 MPH).
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, April 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: 316087.