A high alpine wind sensor reported a wind gust of 84 mph as thunderstorms moved through southwest Colorado.
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The episode as NWS GJT wrote it up.
A high alpine wind sensor reported a wind gust of 84 mph as thunderstorms moved through 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 Jul 20, 2:01 PM MST, 2 hours 59 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND JUNCTION CO 301 PM MDT FRI JUL 20 2012 .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 300 PM MDT FRI JUL 20 2012 A LITTLE DRIER AIR-MASS MOVED INTO THE REGION OVERNIGHT AND TODAY AS EVIDENCED BY WTR VAPOR SATELLITE IMAGES. ALSO THE BEST UPSTREAM SOUNDING THIS MORNING WAS ABQ AND THEY SHOWED SIGNIFICANT DRYING TREND FROM THE MORNING BEFORE. HOWEVER DWPTS AND INFERRED LOW LEVEL MOISTURE HAS INCREASED BY 2-10 DEGREES. THIS AFTERNOON NO SHWRT WV TRIGGER IS SEEN TO REALLY ENHANCE CONVECTION...SO WILL HAVE TO RELY ON SOLAR HEATING. CURRENT RADAR AND STLT PICS AS OF 1430 INDICATE CONVECTION DEVELOPING ON THE DOWNSTREAM SIDE OF RIDGES AND HIGHER TERRAIN...BUT SO FAR NOTHING TO GET EXCITED ABOUT. TONIGHT ACTIVITY WILL GRADUALLY DECREASE AFTER SUNSET AND PRETTY MUCH COME TO AN END BY MIDNIGHT. DEEPER MOISTURE WILL RETURN TO THE REGION SATURDAY AS THE FLOW BECOMES MORE SOUTHERLY WITH PCP WTR VALUES RISING BACK UP TO AROUND 1 INCH. AGAIN NO REALLY DEFINABLE SHRT WV IS SEEN SO EXPECT NO BIG CHANGES IN AREAL COVERAGE OR INTENSITY OF CONVECTION. AS A RESULT SHOWERS AND TSTMS WILL FAVOR THE HIGHER TERRAIN...AND WEAKEN AS THEY DRIFT INTO THE VALLEYS. .LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY) ISSUED AT 300 PM MDT FRI JUL 20 2012 HIGH SUMMER IS UPON US AND REMAINS AS FAR INTO THE FUTURE AS WE CAN PEER. THE SUBTROPICAL RIDGE...THAT IS BRINGING WIDESPREAD DROUGHT TO MUCH OF THE CENTRAL CONUS...REMAINS CENTERED ON THE HIGH PLAINS. WE ARE FORTUNATE TO BE ON THE WESTERN EDGE OF THE RIDGE THAT ALLOWS MONSOONAL MOISTURE TO PERCOLATE UP FROM THE SOUTH. THE LATEST MODELS SHOW THE DEEPEST MOISTURE IN OUR GENERAL VICINITY FOR THE NEXT WEEK. PRECIPITABLE WATER VALUES HOVER AROUND 1 INCH...DEEPEST SOUTH. WITH SLOW STORM MOTION THERE IS SOME POTENTIAL FOR FLASH FLOODING ESPECIALLY SOUTH. OTHER DANGERS INCLUDE LIGHTNING AND LIGHTNING STARTED FIRES...AND GUSTY OUTFLOW WINDS. WITH WET BULB ZERO HEIGHTS MOSTLY ABOVE 15KFT...HAIL WILL BE SMALL AND LIMITED TO THE STRONGEST CORES OVER HIGH TERRAIN. MOISTURE IS QUITE DEEP ON SUNDAY THAT MAY FAVOR MORE WIDESPREAD SHOWERS...SOME LINGERING OVERNIGHT. OTHERWISE NO DISTURBANCES ARE CURRENTLY RESOLVED THAT WOULD INDICATE GREATER SHOWER COVERAGE DURING ANY PARTICULAR PERIOD. TEMPERATURES WILL REMAIN AT OR JUST ABOVE NORMAL. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1029 AM MDT FRI JUL 20 2012 VFR CONDITIONS WILL PREVAIL ACROSS THE REGION FOR THE REMAINDER OF THIS MORNING. THIS AFTERNOON DAYTIME HEATING WILL BRING ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS. BY MIDAFTERNOON...SCATTERED TO NUMEROUS THUNDERSTORM COVERAGE WILL RESULT IN FREQUENT MOUNTAIN OBSCURATIONS AND GUSTY OUTFLOW WINDS TO 45 MPH. REGIONAL AIRPORTS FACE THE BEST CHANCE OF THUNDERSTORMS FROM 21Z TO 03Z WITH THOSE IN CLOSE PROXIMITY TO HIGHER TERRAIN TO THE SOUTH FAVORED. THESE STORMS WILL BRING BRIEF MVFR CIGS AND/OR VSBY IN HEAVY RAIN. SHOWERS AND THUNDERSTORMS WILL DECREASE...BUT NOT FULLY DIMINISH OVERNIGHT. LITTLE CHANGE IS EXPECTED SATURDAY. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...NONE. UT...NONE. && SHORT TERM...MC LONG TERM...JOE AVIATION...MC
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GRAND JUNCTION CO 545 AM MDT FRI JUL 20 2012 COZ001>014-017>023-UTZ022>025-027>029-211200- 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- 545 AM MDT FRI JUL 20 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR EASTERN UTAH AND WESTERN COLORADO. .DAY ONE...TODAY AND TONIGHT SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS AFTERNOON AND EVENING. STORMS WILL FAVOR THE MOUNTAINS...BUT WILL DRIFT OVER THE VALLEYS LATE THIS AFTERNOON AND INTO THE EVENING. GUSTY WINDS TO 45 MPH...HEAVY RAIN...AND SMALL HAIL IS POSSIBLE WITH THE STRONGEST STORMS. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY MONSOON MOISTURE WILL CONTINUE TO SWEEP OVER THE REGION THIS WEEKEND AND INTO THE COMING WEEK. THIS WILL BRING MORE WIDESPREAD SHOWERS AND THUNDERSTORMS TO THE AREA WITH LOCALLY HEAVY RAINFALL AGAIN POSSIBLE. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED. TGJT
The Grand Junction radar (KGJX), 138 km away, was scanning. The volume nearest the first event began at 00:01 UTC.
1 thunderstorm wind. Local standard time, as filed.
The Eagle Mountain weather station measured thunderstorm outflow wind gusts of 84 mph.
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, July 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: 479504.