A developing upper low helped trigger isolated dry thunderstorms over the Mojave Desert. One thunderstorm caused dust storm conditions as it dissipated.
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The episode as NWS VEF wrote it up.
A developing upper low helped trigger isolated dry thunderstorms over the Mojave Desert. One thunderstorm caused dust storm conditions as it dissipated.
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 Las Vegas, NV wrote its last area forecast discussion before the first event at May 7, 8:34 PM PST, 2 hours 56 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LAS VEGAS NV 934 PM PDT MON MAY 7 2012 .SYNOPSIS...LOW PRESSURE OVER THE DESERT SOUTHWEST WILL CONTINUE TO PRODUCE PERIODS OF GUSTY NORTH WINDS ACROSS THE REGION TONIGHT AND TUESDAY. ISOLATED SHOWERS WILL ALSO BE POSSIBLE THIS EVENING THROUGH EARLY TUESDAY ACROSS SOUTHERN NEVADA AND NORTHWEST ARIZONA. QUIET WEATHER IS THEN EXPECTED FROM WEDNESDAY INTO THE WEEKEND...WITH LIGHTER WINDS AND TEMPERATURES RISING SEVERAL DEGREES ABOVE NORMAL. && .UPDATE...THUNDERSTORMS DEVELOPED RIGHT UNDER THE UPPER LOW THIS EVENING IN THE LAS VEGAS AREA. THEY PROBABLY WILL NOT LAST LONG AND VERY LITTLE IF ANY RAIN IS EXPECTED. UPDATED TO ADD A SLIGHT CHANCE OF THUNDERSTORMS THIS EVENING FOR THE AREA CLOSE TO THE LOW CENTER. -HARRISON- && .PREV UPDATE...CLOUDS DEVELOPED ON THE SOUTHWEST SIDE OF THE CLOSED LOW MOVING OVER THE AREA THIS EVENING. UPDATED SKY GRIDS FOR MORE CLOUD COVER ACROSS MAINLY SAN BERNARDINO COUNTY THIS EVENING. ALSO DECREASED CLOUD COVER OVER NORTHERN LINCOLN COUNTY WHERE CLOUDS WERE DIMINISHING AS THE LOW SHIFTED SOUTH. ROOF DAMAGE TO A COUPLE OF BUSINESSES IN LAS VEGAS OCCURRED THIS AFTERNOON FROM WIND GUSTS. THERE WAS CERTAINLY POTENTIAL FOR DOWNBURST WINDS FROM WEAK SHOWERS DUE TO EXTREMELY DRY AIR BELOW CLOUD BASES AND AN UNSTABLE ATMOSPHERE. HOWEVER...AFTER ONE OF THE AREAS WAS SURVEYED AND THE PUBLIC WAS INTERVIEWED...IT WAS DETERMINED THAT THE DAMAGE WAS LIKELY CAUSED BY STRONG DUST DEVILS. -HARRISON- && .PREV DISCUSSION... 340 PM PDT MON MAY 7 2012 .SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT...THE CIRCULATION ROLLING OUT OF SOUTHWEST UTAH INTO SOUTHERN NEVADA COULD CLEARLY BE SEEN ON SATELLITE LOOPS THIS AFTERNOON. WEAK RADAR RETURNS INDICATED VIRGA AND LIGHT SHOWERS MOVING DOWN THROUGH SOUTHERN LINCOLN COUNTY AND THESE WILL SPREAD DOWN THROUGH CLARK AND NORTHERN MOHAVE COUNTIES LATE THIS AFTERNOON AND EVENING. NO LIGHTNING HAS BEEN DETECTED AND IT APPEARS THAT VIRGA AND LIGHT SHOWERS ARE ABOUT ALL THAT CAN BE EXPECTED IN TERMS OF PRECIPITATION...CONSIDERING THE RELATIVELY SHALLOW LAYER OF MOISTURE INDICATED IN FORECAST SOUNDINGS...GENERALLY BETWEEN 14 KFT AND 22 KFT MSL. HOWEVER...THERE WILL BE A SLIGHT POTENTIAL FOR MICROBURSTS GIVEN THE VERY DRY AND DEEP SUBCLOUD LAYER. WITH GRADIENT WIND GUSTS PUSHING 30 MPH...THERE COULD BE LOCALIZED GUSTS UP TO 50 MPH NEAR VIRGA/SHOWERS THIS EVENING. THE CENTER OF THE UPPER LEVEL CIRCULATION IS FORECAST TO RIDE DOWN THE CALIFORNIA/ARIZONA BORDER AND OVER THE NORTHERN GULF OF CALIFORNIA TUESDAY AFTERNOON. SOME LINGERING WRAP AROUND MOISTURE MAY PRODUCE A FEW MORE SHOWERS OR THUNDERSTORMS OVER MOHAVE COUNTY TUESDAY AFTERNOON BEFORE IT MOVES COMPLETELY OUT. NORTH WINDS WILL ALSO INCREASE AGAIN ON THE BACK SIDE OF THE SYSTEM AS THE PRESSURE GRADIENT STRENGTHENS. HOWEVER...GUSTS SHOULD GENERALLY BE LESS THAN 35 MPH. THE RIDGE NOSING INTO THE GREAT BASIN FROM THE EASTERN PACIFIC WILL BRING HIGH TEMPERATURES IN THE DESERTS BACK INTO THE MID 90S BY WEDNESDAY. .LONG TERM...THURSDAY THROUGH SUNDAY...SHORT WAVE TROUGH MOVING ACROSS THE PACIFIC NORTHWEST WILL RESULT IN BASICALLY ZONAL FLOW ACROSS THE CWA ON THURSDAY. THE MAIN DYNAMICS WILL REMAIN WELL TO THE NORTH OF THE CWA WITH MAINLY VARIABLE HIGH LEVEL MOISTURE FLOWING ACROSS THE AREA...HOWEVER WILL INCLUDE GHOST POPS OVER NORTHERN LINCOLN COUNTY AS THE TRAILING FEATURE CROSSES THE AREA. ZONAL FLOW TO THEN REMAIN OVER THE AREA THROUGH EARLY SATURDAY BEFORE RIDGING JUST OFF THE WEST COAST ALLOWS A SHORT WAVE TROUGH TO DROP SOUTH ALONG THE ROCKIES ON SUNDAY. OVERALL LITTLE CHANGE TO THE WEATHER OVER THE CWA ALTHOUGH THE FLOW ALOFT BECOMES MORE NORTHERLY. THIS MAY RESULT IN A LITTLE MORE AFTERNOON WIND AND A FEW DEGREES OF COOLING...BUT OVERALL LITTLE CHANGE EXPECTED OVER THE WEEKEND. WITH THIS SAID...UNDER THE ZONAL OR WEAK NORTH FLOW...DAYTIME TEMPERATURES ARE EXPECTED TO BE NEAR TO SLIGHTLY ABOVE NORMAL THROUGH THE LONG TERM. && .AVIATION...FOR MCCARRAN...NORTHWEST WINDS 13-25KTS TO CONTINUE THROUGH 04Z THEN DECREASE TO BETWEEN 8-15KTS OVERNIGHT. NORTH TO NORTHEAST WINDS ARE EXPECTED ON TUESDAY FROM 17-23Z BETWEEN 10-20KTS. A MINOR INCREASE IN MOISTURE WILL ALLOW FOR A SLIGHT CHANCE OF A SHOWER OVER THE SPRING MOUNTAINS/SHEEP RANGE TONIGHT...BUT THE CHANCE IS WELL BELOW CRITERIA TO MENTION IN THE TAF. NEARBY SHOWERS MAY PRODUCE DOWNBURST WIND GUSTS TO OVER 40KTS BUT NOT EXPECTED AT THE TERMINAL. CLOUDS TO BE SCT-BKN AOA 12K FEET THROUGH THE NIGHT WITH FEW-SCT CLOUDS TUESDAY. FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST CALIFORNIA...A WEAK LOW PRESSURE SYSTEM MOVING ACROSS SOUTHERN NEVADA TONIGHT WILL GENERALLY KEEP NORTHERLY WINDS ACROSS THE AREA OVERNIGHT WITH SPEEDS BETWEEN 10-20KTS WITH LOCALLY HIGHER GUSTS. HIGHER GUSTS WILL ALSO BE SEEN IN THE COLORADO RIVER VALLEY. THERE WILL BE A SLIGHT CHANCE OF SHOWERS OVER THE SOUTHERN NEVADA MOUNTAINS AS WELL AS THE PEACH SPRINGS AND MORMON MESA CORRIDORS. CLOUDS WILL GENERALLY BE AOA 10K FEET OVERNIGHT. ON TUESDAY...NORTH WINDS TO CONTINUE MOST AREAS WITH SPEEDS 10-20KTS WITH FEW-SCT CLOUDS AOA 12K FEET. && .VEF WATCHES/WARNINGS/ADVISORIES... NV...NONE. AZ...NONE. CA...NONE. && ADAIR/JENSEN HTTP://WEATHER.GOV/LASVEGAS
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE LAS VEGAS NV 211 AM PDT MON MAY 7 2012 AZZ002-036-CAZ527-NVZ021-080700- LOWER COLORADO RIVER VALLEY-LAKE MEAD NATIONAL RECREATION AREA- SAN BERNARDINO COUNTY-UPPER COLORADO RIVER VALLEY- 211 AM PDT MON MAY 7 2012 /211 AM MST MON MAY 7 2012/ THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHWEST ARIZONA...CALIFORNIA AND SOUTHERN NEVADA. .DAY ONE...TODAY AND TONIGHT STRONG NORTH WINDS DOWN THE COLORADO RIVER WILL CAUSE HAZARDOUS BOATING CONDITIONS...DIFFICULT DRIVING CONDITIONS ON BRIDGES CROSSING THE RIVER...AND CONDITIONS FAVORABLE FOR RAPID FIRE GROWTH AND SPREAD. A WIND ADVISORY AND A RED FLAG WARNING ARE IN EFFECT THROUGH THIS AFTERNOON. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED TODAY. HOWEVER...SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. AZZ001-003-CAZ519>526-NVZ014>020-022-080700- NORTHWEST PLATEAU-NORTHWEST DESERTS-EASTERN SIERRA SLOPES- OWENS VALLEY-WHITE MOUNTAINS OF INYO COUNTY- DEATH VALLEY NATIONAL PARK-WESTERN MOJAVE DESERT- EASTERN MOJAVE DESERT-MORONGO BASIN-CADIZ BASIN- ESMERALDA AND CENTRAL NYE COUNTY-LINCOLN COUNTY- NORTHEAST CLARK COUNTY-WESTERN CLARK AND SOUTHERN NYE COUNTY- SHEEP RANGE-SPRING MOUNTAINS-LAS VEGAS VALLEY- SOUTHERN CLARK COUNTY- 211 AM PDT MON MAY 7 2012 /211 AM MST MON MAY 7 2012/ THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHWEST ARIZONA...CALIFORNIA AND SOUTHERN NEVADA. .DAY ONE...TODAY AND TONIGHT NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED TODAY. HOWEVER...SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. MORGAN
The national radar mosaic for the moment the first event began.
1 dust storm. Local standard time, as filed.
Strong winds from a dissipating dry thunderstorm knocked out power to Amboy, and blowing dust reduced visibility to less than a quarter mile for about two hours.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2012Every state in 2012This day in weather historyWarnings in California, May 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: 370645.