A major surge of monsoon moisture brought an outbreak of thunderstorms to the Mojave Desert and southern Great Basin, with the most activity on the 3rd and 4th. Widespread flash flooding and severe weather occurred.
Every event with a place to put it; 1 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 VEF wrote it up.
A major surge of monsoon moisture brought an outbreak of thunderstorms to the Mojave Desert and southern Great Basin, with the most activity on the 3rd and 4th. Widespread flash flooding and severe weather occurred.
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 Aug 2, 8:55 AM PST, 23 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LAS VEGAS NV 955 AM PDT SAT AUG 2 2014 .SYNOPSIS...INCREASING THUNDERSTORM COVERAGE WITH A RISK OF HEAVY RAIN CAN BE EXPECTED TODAY AND SUNDAY AS DEEPER MOISTURE AND A POTENT UPPER LEVEL DISTURBANCE MOVE IN FROM THE SOUTH. THIS WILL BE FOLLOWED BY A DRYING TREND FROM SOUTHWEST TO NORTHEAST EARLY NEXT WEEK. && .UPDATE... CONTINUE TO WATCH CONVECTION ACROSS MAINLY THE FAR SOUTHERN TIP OF CLARK...SOUTHERN MOHAVE...AND EASTERN SAN BERNARDINO COUNTIES. AN OUTFLOW BOUNDARY MOVING SOUTH THROUGH THAT REGION IS WORKING INTO A MOIST ATMOSPHERE. CONVECTION SHOULD CONTINUE TO DEVELOP OVER THE NEXT FEW HOURS AND GRADUALLY SLIDE SOUTHWEST. SO LOOK FOR CONVECTION TO CONTINUE FOR A LITTLE LONGER FROM NEEDLES/LAKE HAVASU IN THE EAST TO TWENTYNINE PALMS/JOSHUA TREE IN THE WEST. THIS ACTIVITY IS ALSO SUPPORTED BY AN INVERTED TROUGH ALOFT...STRETCHING NORTH FROM NORTHERN BAJA. AS THE INVERTED TROUGH MOVES WEST AND THE OUTFLOW MOVES SOUTH OUT OF THE FORECAST AREA...THIS ACTIVITY WILL WANE LATE THIS MORNING. THEN WE WILL WAIT FOR THE ATMOSPHERE TO DESTABILIZE FOR OUR NEXT ROUND. BELIEVE IT WILL BE A LATER START THANKS TO CLOUDS AND CURRENT CONVECTION...BUT THAT COULD CHANGE IN MOHAVE COUNTY WHERE WE MAY HAVE SOME DIFFERENTIAL HEATING BOUNDARIES ALONG THE SHARP CLOUD SHIELD. WILL CONTINUE TO MONITOR. AS FOR THE FORECAST...DID UPDATE POPS...SKY...AND QPF FOR THE CURRENT PLACEMENT OF CONVECTION. ALSO REMOVED POPS ELSEWHERE FOR THE NEXT FEW HOURS AS WE ARE NOT EXPECTING DEVELOPMENT WITHIN THIS TIME FRAME. HAVE GONE WITH A SLOW DIURNAL TEMP TREND FOR MOST AREAS THIS MORNING...WITH THE CLOUD COVER. HOWEVER...AS THE INVERTED TROUGH MOVES WEST AND CLOUDS SCATTER...TEMPS SHOULD PEAK LATE AFTERNOON. && .PREVIOUS UPDATE... 538 AM PDT SAT AUG 2 2014 RAISED MORNING POPS OVER CLARK COUNTY TO ACCOUNT FOR CURRENT RADAR TRENDS. STORMS HAVE BEEN REDEVELOPING/MOVING SLOWLY CLOCKWISE UNDER THE RIDGE CENTER OVERNIGHT...AND WILL ENTER THE LAS VEGAS VALLEY FROM THE SOUTH BEFORE 7 AM IF THEY HOLD TOGETHER. && .PREVIOUS DISCUSSION... 200 AM PDT SAT AUG 2 2014 .SHORT TERM...THROUGH SUNDAY NIGHT...NOT MUCH CHANGE TO PREVIOUS THINKING. POTENT UPPER LEVEL DISTURBANCE NEAR THE BAJA SPUR THIS MORNING WAS STILL TRACKING NORTHWARD AND ADVECTING DEEP SUBTROPICAL MOISTURE NORTHWARD AROUND ITS EASTERN SEMICIRCLE. DEEP MOISTURE WILL OVERSPREAD OUR AREA TONIGHT THROUGH SUNDAY NIGHT AND THE DISTURBANCE WILL SLOWLY TRACK NORTH ACROSS SOUTHERN CALIFORNIA...HELPING TO LIFT THE MOIST AIRMASS AND PRODUCE LOCALLY HEAVY RAIN. FLASH FLOOD WATCH LOOKS GOOD AND WILL REMAIN IN PLACE. TEMPERATURES WILL BE UNSEASONABLY COOL WITH THE CLOUD COVER AND RAINFALL...BUT THE HIGH MOISTURE CONTENT WILL MAKE IT FEEL QUITE STICKY. .LONG TERM...MONDAY THROUGH THURSDAY...THE UPPER LOW MOVING UP FROM THE SOUTH IS FORECAST BY ALL THE MODELS TO BE CENTERED OVER WESTERN NEVADA MONDAY MORNING WITH ANOTHER SHORTWAVE ROTATING AROUND THE BASE OF THE LOW INTO THE FORECAST AREA. THIS WILL MEAN A GOOD CHANCE OF SHOWERS AND THUNDERSTORMS NORTH AND EAST OF THIS SHORTWAVE...IN OTHER WORDS THE NORTHEAST HALF OF THE FORECAST AREA. I WENT WITH LIKELY POPS FOR A GOOD PORTION OF LINCOLN AND NORTHERN MOHAVE COUNTIES. SOME CLEARING MAY BE POSSIBLE MONDAY AFTERNOON IN WESTERN SAN BERNARDINO COUNTY BEHIND THE SHORTWAVE. PRECIPITATION CHANCES WILL DECREASE FROM SOUTHWEST TO NORTHEAST MONDAY NIGHT AS THE SHORTWAVE WORKS INTO UTAH. SOUTHWEST FLOW WILL BE OVER THE AREA TUESDAY AND WEDNESDAY WITH A PACIFIC TROUGH MOVING INTO CALIFORNIA. SOME LINGERING MOISTURE WILL COMBINE WITH THIS TROUGH TO KEEP A SLIGHT CHANCE OF THUNDERSTORMS ACROSS THE NORTHERN PORTION OF THE FORECAST AREA. MODELS ARE IN GOOD AGREEMENT MOVING THE TROUGH INTO NEVADA THURSDAY WHICH WILL HELP KEEP A SLIGHT CHANCE OF THUNDERSTORMS ACROSS THE NORTH EVEN THOUGH DRIER AIR WILL BE MOVING IN. TEMPERATURES IN THE LONG TERM WILL START OUT PRETTY COOL MONDAY WITH THE UPPER LOW OVER THE AREA...ALTHOUGH NOT AS COOL AS WE ARE FORECASTING FOR SUNDAY. THEN TEMPERATURES WILL WARM TO NEAR NORMAL BY WEDNESDAY AND THURSDAY. && .AVIATION...FOR MCCARRAN...IT WILL BE A DIFFICULT WEEKEND WITH CHANCES FOR THUNDERSTORMS NEAR THE TERMINAL AND IN ALL APPROACH CORRIDORS...RESULTING IN PERIODS OF LOW CEILINGS AND NUMEROUS OUTFLOW BOUNDARIES WHICH WILL BRING SHIFTING WINDS TO THE AIRPORT. FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST CALIFORNIA...THUNDERSTORM CHANCES WILL INCREASE AREAWIDE TODAY AND SUNDAY...WITH THE MAIN CONCERNS BEING VERY HEAVY RAIN AND ERRATIC GUSTY WINDS. && .SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION MAY BE NEEDED TODAY AND SUNDAY FOR THUNDERSTORMS WITH VERY HEAVY RAIN AND POTENTIAL FLASH FLOODING. && UPDATE...PADDOCK PREVIOUS UPDATE...MORGAN SHORT TERM/AVIATION...MORGAN LONG TERM...HARRISON FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE: HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
The Edwards AFB radar (KEYX), 129 km away, was scanning. The volume nearest the first event began at 17:01 UTC.
12 flash flood, 1 dust storm. Local standard time, as filed.
Dust storm conditions on Interstate 40 near Newberry Springs led to a series of accidents involving seven big rigs and three cars. Nine people were injured (indirect).
Several inches of water and mud flowed over roads in the Manzanar National Historic Site, closing the auto tour road.
Rocks and debris washed onto sections of Whitney Portal Road from west of Lone Pine all the way to the parking area for the trail.
Flash flooding along Highway 62 closed the highway, trapping about 400 cars between flooded washed. One swift water rescue occurred.
Highway 95 flooded in multiple places between Needles and Vidal Junction.
Cedar Canyon Road was blocked by a large flow of mud and rocks.
Water and mud washed over National Trails Highway near Amboy.
One to two feet of water flowed through streets in southwest Barstow. At least five swift water rescues took place, three homes were flooded with water and mud, and a 20-inch sewer line was ruptured. Lenwood Road was washed out in sections between National Trails Highway and the I-15 on ramp, with one vehicle stuck. The intersection of Calico Blvd. and Ghost Town Road was also flooded with a vehicle stuck. Minneola Road was closed from Mitchells Ranch to Valley Center. A two-vehicle crash occurred during the heavy rain, injuring two people (indirect).
Rocks and debris flowed over National Trails Highway at Ludlow Road.
The intersection of Highways 58 and 395 was fully flooded.
Highway 395 was flooded near San Bernardino County mile marker 32.
A foot of water and debris flowed over Highway 190 at State Line Road just outside Death Valley National Park. The water also burst into the historic Amargosa Opera House, warping the original wood floors in the 91 year old building.
Ubehebe Crater Road was closed at the junction with Scotty's Castle Road due to flood damage.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2014Every state in 2014This day in weather historyWarnings in California, August 2014
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: 538737, 538739, 538741, 538743, 538744, 538745, 538746, 538751, 538757, 538753, 538763, 538766, 538771.