A moist west to southwest flow over the area with embedded disturbances produced significant snowfall in most mountain areas of western Colorado and some lower elevation areas of northwest Colorado.
Every event with a place to put it; 7 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 GJT wrote it up.
A moist west to southwest flow over the area with embedded disturbances produced significant snowfall in most mountain areas of western Colorado and some lower elevation areas of northwest Colorado.
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 Grand Junction, CO wrote its last area forecast discussion before the first event at Apr 5, 2:40 PM MST, 11 hours 20 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND JUNCTION CO 340 PM MDT TUE APR 5 2011 .SHORT TERM...TONIGHT THROUGH THURSDAY... A WEAK COOL FRONT CURRENTLY IN NW UTAH WILL PUSH THROUGH NE UTAH THIS EVENING THEN DOWN TO THE ROAN-TAVAPUTS PLATEAUS BY MORNING. THIS WILL PROVIDE A FOCUS FOR SHOWERS THAT WILL BE LIMITED MAINLY TO THE UT/CO-WY STATE LINE. THE EASTERN UINTA AND ELKHEAD MTNS COULD GET A FEW INCHES OF SNOW. LIGHT SHOWERS WILL CONTINUE ALONG THIS BOUNDARY INTO WEDNESDAY MORNING. MEANWHILE THE CLOSED LOW OFF THE BAJA WILL OPEN AND PUSH INLAND SPREADING MOISTURE INTO THIS FORECAST AREA. MAINLY MOUNTAIN SHOWERS WILL BE ON THE INCREASE WEDNESDAY AFTERNOON. DEEP MOISTURE POURS INTO THE REGION WEDNESDAY NIGHT FROM THE FOUR CORNERS TO NORTH OF VAIL PASS. MODELS ARE PRODUCING SIGNIFICANT SNOWFALL OVER SW-FACING SLOPES ESPECIALLY THE SW SAN JUANS AND WEST ELKS BUT AS FAR NORTH AS THE FLATTOPS. SNOW LEVEL WILL LOWER TO AROUND 7KFT OVERNIGHT. THIS DEEPER MOISTURE SHIFTS EAST ON THURSDAY LEAVING SCATTERED SHOWERS OVER THE REGION. SW WINDS INCREASE THURSDAY AFTERNOON TO 35- 45 MPH IN THE MOUNTAINS. SNOW LEVELS RISE TO AROUND 9KFT IN THE AFTERNOON. .LONG TERM...THURSDAY NIGHT THROUGH TUESDAY... AN UNSETTLED AND PROGRESSIVE PATTERN CONTINUES THROUGH MOST OF THE LONG TERM PERIOD. A STRONG LOW PRESSURE SYSTEM WILL DIG SOUTHWARD OVER THE WESTERN CONUS THROUGH FRIDAY BEFORE SWINGING ACROSS THE GREAT BASIN AND OVER OUR FORECAST AREA. THE SOUTHWEST FLOW WILL CARRY INCREASING MOISTURE AND INSTABILITY KEEPING SOME PRECIPITATION ONGOING AHEAD OF THE MAIN LOW. THE FAVORED AREAS WILL REMAIN ALONG THE WESTERN EDGE...ESPECIALLY OVER SOUTH FACING SLOPES. ONCE THE MAIN TROUGH MOVES OUT OF THE GREAT BASIN...SHOWERS WILL INCREASE ACROSS THE ENTIRE FORECAST AREA. THERE CONTINUES TO BE SOME DIFFERENCES IN TIMING WITH THE GFS STILL THE FASTER MODEL. THE 12Z GFS TIMES THE TROUGH AXIS OVER THE UT/CO BORDER AT 18Z SAT...ABOUT 12 HOURS FASTER THAN THE ECMWF. THE 18Z NAM12 IS JUST A LITTLE SLOWER THAN THE GFS AT 06Z SAT...POSSIBLY SUPPORTING THE FASTER SOLUTION. SO CONTINUED TO BROAD BRUSH THE FORECAST THROUGH THE WEEKEND. THIS SYSTEM PROMISES TO BRING SIGNIFICANT PRECIPITATION TO THE AREA WITH ITS DEEP MOISTURE AND STRONG DYNAMICS...WITH A -28 COLD CORE MOVING OVER THE 4-CORNERS AT THE BASE OF THE TROUGH. THE NORTHWEST FLOW BEHIND THE TROUGH WILL BE SHORT-LIVED WITH THE NEXT SHORTWAVE MOVING ACROSS THE NORTHERN TIER EARLY IN THE NEXT WORK WEEK. && .AVIATION... VFR PREVAILS THROUGH WEDNESDAY MORNING FOR ALL BUT THE NORTHERN MOST PORTION OF THE FORECAST AREA. A COLD FRONT WILL PUSH THROUGH KVEL PRIOR TO 06Z AND THROUGH KHDN BEFORE 12Z. SNOW SHOWERS AND MVFR CIGS AND VSBY WILL BE LIMITED MAINLY NORTH OF A LINE FROM KVEL-KHDN- KSBS. MOISTURE INCREASES FROM THE SOUTHWEST WEDNESDAY AFTERNOON WITH SCATTERED SHOWERS AND LOCALLY RESTRICTED VSBY MAINLY FORMING OVER HIGHER TERRAIN. CIGS AND VSBY WILL LOWER QUICKLY WEDNESDAY EVENING. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...NONE. UT...NONE. SHORT TERM.....JOE LONG TERM......EH AVIATION.......JOE
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GRAND JUNCTION CO 600 AM MDT TUE APR 5 2011 COZ001>014-017>023-UTZ022>025-027>029-061200- ANIMAS RIVER BASIN-ARCHES/GRAND FLAT-CANYONLANDS/NATURAL BRIDGES- CENTRAL COLORADO RIVER BASIN- CENTRAL GUNNISON AND UNCOMPAHGRE RIVER BASIN- CENTRAL YAMPA RIVER BASIN-DEBEQUE TO SILT CORRIDOR- EASTERN UINTA BASIN-EASTERN UINTA MOUNTAINS- ELKHEAD AND PARK MOUNTAINS-FLAT TOPS- FOUR CORNERS/UPPER DOLORES RIVER- GORE AND ELK MOUNTAINS/CENTRAL MOUNTAINS-GRAND AND BATTLEMENT MESAS- GRAND VALLEY-LA SAL AND ABAJO MOUNTAINS-LOWER YAMPA RIVER BASIN- NORTHWEST SAN JUAN MOUNTAINS-PARADOX VALLEY/LOWER DOLORES RIVER- ROAN AND TAVAPUTS PLATEAUS-SAN JUAN RIVER BASIN-SOUTHEAST UTAH- SOUTHWEST SAN JUAN MOUNTAINS-TAVAPUTS PLATEAU- UNCOMPAHGRE PLATEAU AND DALLAS DIVIDE-UPPER GUNNISON RIVER VALLEY- UPPER YAMPA RIVER BASIN-WEST ELK AND SAWATCH MOUNTAINS- 600 AM MDT TUE APR 5 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR EASTERN UTAH AND WESTERN COLORADO. .DAY ONE...TODAY AND TONIGHT... GUSTY WINDS WILL DEVELOP THIS AFTERNOON. SNOW WILL DEVELOP OVER THE EASTERN UINTA MOUNTAINS AND THE ELKHEAD MOUNTAINS...AND POSSIBLY PARK RANGE TONIGHT. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY... RAIN AND SNOW WILL INCREASE WEDNESDAY AND WEDNESDAY NIGHT. TRAVEL CONDITIONS WILL DETERIORATE OVER HIGH MOUNTAIN PASSES DUE TO ACCUMULATING SNOW. AN EXTENDED PERIOD OF SIGNIFICANT WEATHER IS EXPECTED THURSDAY THROUGH SATURDAY AS A STRONG PACIFIC STORM MOVES OVER THE AREA. MOUNTAIN SNOW...VALLEY RAIN...AND AFTERNOON AND EVENING THUNDERSTORMS SHOULD ACCOMPANY THIS STORM. WINDY CONDITIONS WILL DEVELOP THURSDAY AFTERNOON...ESPECIALLY ACROSS THE CENTRAL AND SOUTHERN VALLEYS. ANOTHER WEATHER SYSTEM WILL BRING A CHANCE OF SNOW ON MONDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED TODAY OR TONIGHT. TGJT
The national radar mosaic for the moment the first event began.
7 winter weather. Local standard time, as filed.
Snowfall of 5 to 12 inches was measured across the area. Winds gusted 20 to 30 mph and produced local blowing and drifting snow.
Snowfall of 3 to 4 inches was measured across the area.
Snowfall of 3 to 6 inches was measured across the area.
Snowfall of 5 to 12 inches was measured across the area. Winds gusted 20 to 30 mph and produced local blowing and drifting snow.
Snowfall of 3 to 7 inches was measured across the area. Winds gusted 20 to 35 mph and produced local blowing and drifting snow.
Snowfall of 5 to 11 inches was measured across the area. Winds gusted 25 to 40 mph and produced areas of blowing and drifting snow.
Snowfall of 4 to 12 inches was measured across the area. Winds gusted 25 to 45 mph and produced areas of blowing and drifting snow.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2011Every state in 2011This day in weather historyWarnings in Colorado, 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: 314269, 314270, 314271, 314272, 314266, 314267, 314268.