A moist and unstable southerly flow ahead of a low pressure system over the southwestern states brought significant snowfall to the San Juan Mountains.
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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 and unstable southerly flow ahead of a low pressure system over the southwestern states brought significant snowfall to the San Juan Mountains.
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 Mar 21, 3:00 AM MST, 0 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND JUNCTION CO 400 AM MDT WED MAR 21 2007 .SHORT TERM (TODAY THROUGH THURSDAY NIGHT)... THE FIRST FULL DAY OF SPRING USHERS IN UNSETTLED WEATHER. THE WESTERN TROF SPLITS TODAY WITH THE NORTHERN BRANCH PROGRESSING THRU THE NORTHERN ROCKIES. THE SOUTHERN PORTION DIGS AND CLOSES OFF OF BAJA AND BEGINS TO NUDGE INTO NW MEXICO THURSDAY NIGHT. THIS LEAVES THE FORECAST AREA IN AN UNSETTLED SW FLOW. 75KT JET IS NOSING INTO THE FOUR CORNERS THIS MORNING...RESULTING IN SOME SURFACE MIXING OF THE STRONG GRADIENT WINDS AND KEEPING TEMPS MILD. LOOSELY FOLLOWED THE GFS MILDER TEMPS AND QPF FIELDS. TODAY-THIS EVENING: JET NOSE SLIDES EAST THRU THE DAY. COOLER AIR ALOFT ADVECTS INTO THE CWA FROM THE WEST. 700 TEMPS THAT WERE 6C ON TUESDAY WILL LOWER TO NEAR -1C NORTH 2C SOUTH. ASSOCIATED SURFACE COLD FRONT SAGS INTO NE UTAH THIS AFTERNOON AND THEN BECOMES ORIENTED...THIS EARLY EVENING...FROM THE ROAN-TAVAPUTS SOUTHWEST TO VICINITY OF LAKE POWELL. THE 06Z WRF IS SHOWING GOOD SFC CONVERGENCE/FRONTOGENETICAL FORCING IN THE LA SAL/ABAJO MTNS OF SE UTAH...WHILE THE GFS PUTS THIS CONVERGENCE WEST OF THE COLORADO RIVER. BUT WITH INCREASED MID-LEVEL MOISTURE AND INSTABILITY IN PLACE EXPECT SHOWERS AND AFTERNOON THUNDERSTORMS. THE SW SAN JUANS ARE FAVORED FOR INCREASED OROGRAPHIC SHOWERS. SNOW LEVEL 8-9KFT N TO S...BUT AFTERNOON CONVECTION WILL DRIVE LOCAL SNOW SHOWERS AS MUCH AS 2KFT LOWER. EXPECT MTN SNOW ACCUMULATIONS TO STAY BELOW ADVISORY CRITERIA...THOUGH LOCAL THUNDERSTORMS IN THE 4-CORNERS AREA WILL PRODUCE SOME BRIEF BUT IMPRESSIVE HEAVY SNOWFALL. LATE TONIGHT-THURSDAY NIGHT: SW GRADIENT DIMINISHES SOMEWHAT AND BACKS TO A DRIER WEST FLOW ACROSS THE NORTH. INSTABILITY SHOWERS WILL FAVOR THE SOUTH. RAMEY .LONG TERM (FRIDAY THROUGH TUESDAY)... FRIDAY THROUGH SUNDAY...MEDIUM RANGE MODELS HAVE CONVERGED TO A SOLUTION WITH THE EVOLUTION OF THE CLOSED LOW...EXPECTED TO EJECT NORTHEAST FROM NWRN OLD MEXICO FRIDAY NIGHT AND REACH THE CENTRAL PLAINS ON SUNDAY. SUSPECT THERE WILL STILL BE SOME TIMING ISSUES TO RESOLVE...BUT THE OVERALL TREND WILL BE AN INCREASING THREAT OF SHOWERS FROM THE SOUTH ON FRIDAY. THE CORE OF THE CLOSED LOW NEVER CROSSES ANY PART OF OUR FORECAST AREA...BUT WRAPAROUND MOISTURE AND LOW STATIC STABILITY WILL CONTRIBUTE FOR A GOOD CHANCE OF SHOWERS. SNOW LEVELS WILL BE HIGH AND THEREFORE NOT EXPECTING SIGNIFICANT SNOWFALL BELOW 10K FEET...BUT HIGH MOUNTAIN PASSES SUCH AS RED MOUNTAIN AND MONARCH COULD EXPERIENCE ACCUMULATING SNOWFALL. EVEN THE NORTHERN PASSES (VAIL AND RABBIT EARS) MAY HAVE A PERIOD OF ACCUMULATING SNOW AS WINDS BACK AROUND TO NORTHWEST AS THE CLOSED LOW MOVES OVER SOUTHEAST COLORADO SATURDAY AFTERNOON AND EVENING. APPEARS THAT NORTHEAST UTAH WILL STAY DRY FROM FRIDAY THROUGH SUNDAY. TEMPERATURES STAY MILD THROUGH THE PERIOD...BUT SHOWERS WILL DEFINITELY COOL OFF IN THE MOUNTAINS. POSSIBLE THAT SATURDAYS VALLEY MAXIMUMS MAY BE COOLER THAN INDICATED IF WIDESPREAD SHOWERS DEVELOP...BUT WILL NOT DEVIATE MUCH FROM GUIDANCE. RESIDUAL MOISTURE AND SURFACE HEATING MAY STILL GENERATE ISOLATED MOUNTAIN SHOWERS ON SUNDAY. DRIER DAY ON MONDAY WITH BUILDING HEIGHTS OVER COLORADO. THE GFS SHOWS A SHARP AND NOTABLY COLDER TROUGH BUSTING ACROSS THE GREAT BASIN ON TUESDAY. LOW POPS ADVERTISED OVER THE MOUNTAIN AREAS IN THE PREFRONTAL AIR MASS WITH COOLING TEMPERATURES ALOFT. BELIEVE THAT THE ECMWF HAS THE BETTER IDEA WITH A SLOWER EASTWARD PROGRESSION. WITH THE SPLITTY NATURE OF THE HEMISPHERIC FLOW OVER THE EASTERN PACIFIC OCEAN...EXPECT DIFFERENT OFFERINGS REGARDING THIS TROUGH WITH EACH MODEL SUITE FOR THE NEXT FEW DAYS. && .GJT WATCHES/WARNINGS/ADVISORIES... .CO...NONE. .UT...NONE. JOE/PF
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GRAND JUNCTION CO 600 AM MDT TUE MAR 20 2007 COZ001>014-017>023-UTZ022-027>029-211200- 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- 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-UNCOMPAHGRE PLATEAU AND DALLAS DIVIDE- UPPER GUNNISON RIVER VALLEY-UPPER YAMPA RIVER BASIN- WEST ELK AND SAWATCH MOUNTAINS- 600 AM MDT TUE MAR 20 2007 THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN COLORADO AND SOUTHEASTERN UTAH. .DAY ONE...TODAY AND TONIGHT GUSTY SOUTHWEST WINDS WILL DEVELOP THIS AFTERNOON AND PERSIST ACROSS THE HIGHER TERRAIN TONIGHT. GUSTS UP TO 30 OR 35 MPH ARE ANTICIPATED IN MANY AREAS AND COULD POSE A PROBLEM FOR HIGH PROFILE VEHICLES. THERE IS A CHANCE OF SNOW ACROSS THE SAN JUAN AND CENTRAL MOUNTAINS LATE TONIGHT. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY SCATTERED RAIN SHOWERS AND MOUNTAIN SNOW SHOWERS ARE EXPECTED ON WEDNESDAY WITH CONTINUED GUSTY WINDS. ISOLATED THUNDERSTORMS ARE POSSIBLE WEDNESDAY AFTERNOON. ACCUMULATING SNOWFALL MAY OCCUR OVER MOUNTAINS PASSES...ESPECIALLY IN THE SAN JUAN AND EASTERN UINTA MOUNTAINS. THURSDAY THROUGH SATURDAY...MOISTURE WILL BE INCREASING FROM THE SOUTH WITH SCATTERED SHOWERS DEVELOPING THURSDAY AFTERNOON AND NIGHT...SNOW LEVELS WILL BE ABOVE 8000 FEET. SCATTERED SHOWERS... MAINLY IMPACTING THE SOUTH...WILL CONTINUE ON FRIDAY BEFORE DECREASING ON SATURDAY. THE THREAT OF ACCUMULATING SNOW WILL BE LIMITED TO THE MOUNTAIN PASSES...MAINLY ABOVE 9000 FEET. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED TODAY AND TONIGHT. UTZ023>025-211200- EASTERN UINTA BASIN-EASTERN UINTA MOUNTAINS-TAVAPUTS PLATEAU- 600 AM MDT TUE MAR 20 2007 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST UTAH .DAY ONE...TODAY AND TONIGHT ISOLATED THUNDERSTORMS ARE POSSIBLE OVER THE EASTERN UINTA MOUNTAINS THIS AFTERNOON. GUSTY SOUTHWEST WINDS WILL DEVELOP THIS AFTERNOON AND PERSIST ACROSS THE HIGHER TERRAIN TONIGHT. GUSTS UP TO 30 OR 35 MPH ARE ANTICIPATED IN MANY AREAS AND COULD POSE A PROBLEM FOR HIGH PROFILE VEHICLES. THERE IS A CHANCE OF RAIN AND MOUNTAIN SNOW SHOWERS AFTER MIDNIGHT. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY SCATTERED RAIN SHOWERS AND MOUNTAIN SNOW SHOWERS ARE EXPECTED ON WEDNESDAY WITH CONTINUED GUSTY WINDS. ACCUMULATING SNOWFALL MAY OCCUR OVER THE EASTERN UINTA MOUNTAINS. MOUNTAIN SNOW SHOWERS WILL DECREASE WEDNESDAY EVENING. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED TODAY AND TONIGHT. JAD
The national radar mosaic for the moment the first event began.
2 winter weather. Local standard time, as filed.
Snowfall of 5 to 10 inches blanketed the area.
Snowfall of 5 to 8 inches blanketed the area.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2007Every state in 2007This day in weather historyWarnings in Colorado, March 2007
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: 20560, 20561.