A closed upper low tracked eastward across the Four Corners area and produced significant snowfall in the western San Juan Mountains of southwest Colorado.
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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 closed upper low tracked eastward across the Four Corners area and produced significant snowfall in the western San Juan Mountains of southwest 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 2, 11:11 AM MST, 49 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND JUNCTION CO 1211 PM MDT MON APR 2 2012 .UPDATE... ISSUED AT 1210 PM MDT MON APR 2 2012 WILL CONTINUE DOWNWARD TREND OF TEMPERATURES THIS AFTERNOON WITH COOL ADVECTION HOLDING THINGS BACK. THE UPPER LOW CONTINUES TO SLOWLY SPIN OVER NORTHWEST NEW MEXICO...PULLING IN MOISTURE ON NORTHEAST WINDS. THERE SEEMS TO BE A CONSISTENT AREA OF CONVERGENCE ALONG THE CENTRAL GUNNISON VALLEY NEAR MONTROSE...WIH COLD AIR OVER-RUNNING AND AN INCREASING CONVECTIVE COMPONENT LEADING TO MODERATE SNOW SHOWERS PASSING THROUGH. STILL EXPECT ACCUMULATIONS TO REMAIN ON GRASSY SURFACES BUT WILL CONTINUE TO MONITOR THIS AREA OVER NEXT FEW HOURS. EXPECT SHOWERS TO INCREASE ACROSS SOUTHERN CWA MOUNTAINS DUE TO LARGE SCALE ASCENT REFOCUSING NEAR THE COLORADO NEW MEXICO BORDER AS THE UPPER LOW SHIFT SLOWLY NORTHEAST. DO EXPECT MORE CLEARING ACROSS THE NORTHERN CWA THROUGH THE AFTERNOON AS THIS HAPPENS AS WELL. UPDATE ISSUED AT 920 AM MDT MON APR 2 2012 UPPER LOW LOOKS TO BE CLOSING OFF AND RE-ORGANIZING OVER THE NEW MEXICO SIDE OF THE 4 CORNERS AREA. MOISTURE WRAPPING AROUND ON THE NORTHEAST FLOW ON BACK SIDE OF THE LOW HAS BROUGHT THE BEST PRECIPITATION TO WEST CENTRAL COLORADO AND EAST-CENTRAL UTAH WHERE LOW LEVEL CONVERGENCE AND GENERAL UPGLIDE HAS LOOKED THE BEST. SO FAR MOST OF THE SNOWFALL HAS BEEN LIMITED TO THE GRASSY AREAS OF THE LOWER ELEVATIONS WITH WEB CAMS AND SPOTTER REPORTS INDICATING 1 TO 2 INCHES ON NEW SNOW IN SPOTS. WILL CONTINUE TO MONITOR THE HIGHER ELEVATIONS THIS AFTERNOON FOR SNOWFALL BUT FOR NOW TOTALS LOOK TO REMAIN UNDER HEADLINE CRITERIA. THE MAIN CONCERN WILL BE OVER THE SOUTHERN MOUNTAINS FROM CRESTED BUTTE SOUTH WHERE THE BEST LARGE SCALE ASCENT AND MOISTURE CONVERGENCE LOOKS TO BE PLACE AS THE UPPER LOW SINKS INTO CENTRAL NEW MEXICO. FOR THIS UPDATE MAIN CONCERN WAS TO BETTER MATCH POPS TO CURRENT CONDITIONS...LOWERED TEMPERATURES...AND INCREASED CLOUD COVER THIS MORNING. UPDATE ISSUED AT 548 AM MDT MON APR 2 2012 CONVERGENCE IS EVIDENT OVER NE UT AND WEST-CENTRAL CO ON SATELLITE AND THE PRECIP PATTERN ON RADAR. FLOW ALOFT WRAPPING AROUND THE LOW THAT HAS BEEN CLOSING OFF JUST SOUTH OF THE FOUR CORNERS IN CONVERGING WITH PREDOMINANTLY NW FLOW ALOFT OVER EASTER UT CREATING AN AREA OF SHOWERS BETWEEN KCNY AND KRIL AND AS FAR NORTH AS KVEL AND KCAG...AND AS FAR SOUTH AS KMTJ AND WESTERN MONTROSE COUNTY. GENERALLY LIGHT PRECIPITATION WILL CONTINUE THROUGH THE MORNING AND TAPER OFF IN THE AFTERNOON. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 440 AM MDT MON APR 2 2012 SHOWERS HAVE SPREAD OVER MUCH OF THE AREA EARLY THIS MORNING AS THE UPPER THROUGH HAS BEEN IN THE PROCESS OF CUTTING OFF A LOW JUST SOUTH OF THE FOUR CORNERS BY SUNRISE. FOR THE LAST COUPLE OF HOURS THE BEST AREA OF SHOWERS HAS BEEN OVER WEST CENTRAL CO/EAST CENTRAL UT WHERE A CONVERGENT ZONE HAS SET UP AS WRAP AROUND FLOW BEGINS TO DEVELOP NORTH OF THE LOW. IT APPEARS THAT SOME OF THE AREAS ALONG THE EASTERN EDGE HAVE YET TO RECEIVE ANY PCPN AS THE BEST MOISTURE STILL ALONG THE UT/CO BORDER. BUT EXPECT THE FAVORED AREA WILL SHIFT TO THE SOUTH AND EAST THIS MORNING AS THE LOW DIGS INTO CENTRAL NEW MEXICO. HOWEVER AS THIS HAPPENS...THE FLOW OVER THE NORTHEAST CORNER WILL TAKE ON A MORE EASTERLY AND THUS DOWNSLOPE COMPONENT...WHICH WILL RESULT IN A DECREASING CHANCE OF PCPN THERE. THIS EASTERLY COMPONENT WILL SPREAD SOUTHWARD BY THE AFTERNOON WITH PCPN RAPIDLY DIMINISHING THROUGH THE DAY AS THE LOW ROTATES ACROSS CENTRAL NEW MEXICO IN AN ARC BEFORE REACHING THE 4-STATE CORNER OF CO/NM/OK/TX BY 12Z TUE. AT THE SURFACE...A LEE SIDE LOW WILL STRENGTHEN OVER EAST NM/WEST TX BY AROUND NOON...AND HIGH PRESSURE WILL MOVE OVER ID. THE GRADIENT BETWEEN THE TWO WILL RESULT IN STRONG NORTHERLY WINDS...ESPECIALLY OVER OUR WESTERN HALF. THE STRONGEST WINDS ARE EXPECTED TO BE MID TO LATE MORNING OVER EASTERN UT AND THE FAR WESTERN EDGE OF CO. THE GRADIENT WILL GRADUALLY DIMINISH THROUGH THE AFTERNOON...AND OVERNIGHT. MUCH COOLER TEMPERATURES ARE IN STORE TODAY AND TONIGHT BEHIND THIS SYSTEM. THE 20 DEGREES OF COOLING EXPECTED STILL LOOKS REASONABLE...WITH NUMBERS DOWN AROUND NORMAL FOR A CHANGE. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 440 AM MDT MON APR 2 2012 MIDRANGE MODELS ARE IN FAIRLY GOOD AGREEMENT THIS MORNING IN PLACING THE CLOSED 500 MB LOW OVER EASTERN NEW MEXICO TUE MORNING THEN LIFTING IT NE INTO SOUTHEASTERN CO THROUGH TUE AND TUE NIGHT. THE GFS TAKES THE MORE NORTHERLY TRACK...THOUGH NOT BY MUCH...AND ROTATES THE MOST MOISTURE AND PCPN ACROSS EASTERN CO AND THE WESTERN CO MOUNTAINS CLOSE TO THE CONTINENTAL DIVIDE. HAVE INCREASED AREAL COVERAGE OF PCPN TUE THROUGH WED MORNING OVER AREAS EAST OF A LINE FROM ABOUT KCAG TO KEGE TO KDRO...ACCOUNTING FOR ALL THE WRAP-AROUND MOISTURE. WED AND THU...ALL THE MODELS MOVE THE MOISTURE EAST OF THE AREA BY WED AFTERNOON...AND HAVE SHOWN DECREASING CLOUDS AND POPS IN THE GRIDS THRU THE DAY. A TRANSITORY RIDGE MOVES OVER THE AREA WED NGT AND THU. BY THU AFTERNOON THE UPPER RIDGELINE IS PROJECTED TO BE OVER EASTERN CO...OPENING THE AREA UP TO INCREASE SW WINDS AHEAD OF THE NEXT PACIFIC SYSTEM. BY THU AFTERNOON THIS SYSTEM WILL BE A BROAD TROUGH OVER THE PACNW WITH A MAX WIND BAND EXTENDING FROM SRN CA THRU NW UT AND SE ID. AS THIS TROUGH MOVES EAST THESE STRONG WINDS SHOULD SPREAD ACROSS EASTERN UT AND WESTERN CO THU AFTERNOON AND REMAIN OVER THE AREA FRIDAY. THE MAJORITY OF THE MOISTURE AND PCPN CHANCES APPEAR TO REMAIN NORTH OF THE FORECAST AREA...SO AT THIS TIME IT APPEARS STRONG WINDS WILL BE THE MAIN THREAT FROM THIS STORM. SAT AND SUN...AS THE MAIN TROUGH MOVES EAST THROUGH THE NORTHERN ROCKIES THE BAND OF STRONG WINDS DOES NOT MOVE MUCH. IT APPEARS WINDY CONDITIONS WILL BE POSSIBLE THROUGH SAT AND SUN. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1210 PM MDT MON APR 2 2012 LOW CLOUDS AND SNOW SHOWERS ARE BRINGING LOWERED FLIGHT CONDITIONS TO THE MJT AND ASE TERMINALS. CONDITIONS HERE ARE MAINLY MVFR BUT MODERATE SNOW SHOWERS THROUGH 20Z NEAR MTJ MAY BRING OCCASSIONAL IFR CIGS AND VSBYS. THERE SHOULD BE SOME IMPROVEMENT TO BOTH OF THESE TERMINALS THROUGH THE LATE AFTERNOON HOURS WITH A RETURN TO VFR EXPECTED BY SUNSET. THE REMAINING TERMINAL SITES LOOK TO PREVAIL AND VFR LEVELS OVER THE NEXT 24 HOURS WITH A FEW SHOWERS IN THE VICINITY OF THESE AIRPORTS POSSIBLE THROUGH SUNSET AS WELL. MOUNTAIN OBSCURATIONS CAN BE EXPECTED OVER THE NEXT 24 HOURS AS MOISTURE WILL CONTINUE TO BE FED INTO THE REGION BY A SLOW MOVING STORM SYSTEM OVER THE SOUTHERN ROCKIES. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...NONE. UT...NONE. && UPDATE...15 SHORT TERM...15 LONG TERM....MC AVIATION...TGJT
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GRAND JUNCTION CO 939 PM MDT SUN APR 1 2012 COZ001>014-017>023-UTZ022>025-027>029-030345- LOWER YAMPA RIVER BASIN-CENTRAL YAMPA RIVER BASIN- ROAN AND TAVAPUTS PLATEAUS-ELKHEAD AND PARK MOUNTAINS- UPPER YAMPA RIVER BASIN-GRAND VALLEY-DEBEQUE TO SILT CORRIDOR- CENTRAL COLORADO RIVER BASIN-GRAND AND BATTLEMENT MESAS- GORE AND ELK MOUNTAINS/CENTRAL MOUNTAIN VALLEYS- CENTRAL GUNNISON AND UNCOMPAHGRE RIVER BASIN- WEST ELK AND SAWATCH MOUNTAINS-FLATTOPS- UPPER GUNNISON RIVER VALLEY-UNCOMPAHGRE PLATEAU AND DALLAS DIVIDE- NORTHWEST SAN JUAN MOUNTAINS-SOUTHWEST SAN JUAN MOUNTAINS- PARADOX VALLEY/LOWER DOLORES RIVER- FOUR CORNERS/UPPER DOLORES RIVER-ANIMAS RIVER BASIN- SAN JUAN RIVER BASIN-SOUTHEAST UTAH-EASTERN UINTA MOUNTAINS- EASTERN UINTA BASIN-TAVAPUTS PLATEAU-ARCHES/GRAND FLAT- LA SAL AND ABAJO MOUNTAINS-CANYONLANDS/NATURAL BRIDGES- 939 PM MDT SUN APR 1 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR EASTERN UTAH AND WESTERN COLORADO. .DAY ONE...TONIGHT GUSTY WINDS WILL CONTINUE OVERNIGHT THOUGH THEY SHOULD WEAKEN SOMEWHAT. AN AREA OF LOW PRESSURE WILL FORM OVER NORTHERN NEW MEXICO TONIGHT WHICH WILL CAUSE OUR WINDS TO SWITCH TO THE NORTH BY TOMORROW. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY GUSTY WINDS ARE EXPECTED AGAIN TOMORROW FOR MUCH OF COLORADO AND UTAH DUE TO THE AREA OF LOW PRESSURE. ONCE IT MOVES OFF...CLEARING CONDITIONS WILL PREVAIL WITH THE NEXT CHANCE FOR PRECIPITATION LOOKING TO BE FRIDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED.
The national radar mosaic for the moment the first event began.
2 winter weather. Local standard time, as filed.
Snowfall accumulations of 4 to 9 inches were measured across the area.
Snowfall accumulations of 3 to 7 inches were measured across about half of the area.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2012Every state in 2012This day in weather historyWarnings in Colorado, April 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: 371213, 371214.