Alert archive / Arizona / Flash Flood Watches in 2021
Flash Flood Watch 1, NWS Las Vegas, NV
NWS Las Vegas, NV issued this flash flood watch at Jul 12, 2021, 1:11 PM MST for Mohave County, Arizona; Clark County, Nevada; San Bernardino County, California. It took effect at Jul 13, 2021, 2:00 PM MST. It was in force for 15 hr.
The area
The counties it named.
The facts
- Issued
- Jul 12, 2021, 1:11 PM MST (20:11 UTC)
- In effect from
- Jul 13, 2021, 2:00 PM MST
- Expired
- Jul 14, 2021, 5:00 AM MST
- In force
- 15 hr
- Issued by
- NWS Las Vegas, NV
- Flood severity
- None
Counties Mohave County, AZ, San Bernardino County, CA, Clark County, NV
The radar
The Las Vegas radar (KESX), 15 km from the middle of the area, began a volume at 20:15 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
The nearest sounding before it
Las Vegas, NV (KVEF), launched 12:00Z, 8.2 hours before the alert went out and 101 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 74 J/kg
- Mixed-layer CIN
- -545 J/kg
- Mixed-layer LCL
- 3475 m above ground
- 0-6 km bulk shear
- 14 kt
- 0-1 km storm-relative helicity
- 37 m²/s²
- 0-3 km storm-relative helicity
- 59 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
780 WGUS65 KVEF 122011 FFAVEF URGENT - IMMEDIATE BROADCAST REQUESTED Flood Watch National Weather Service Las Vegas NV 111 PM PDT Mon Jul 12 2021 AZZ001>003-036-CAZ527-NVZ016-021-131100- /O.NEW.KVEF.FF.A.0001.210713T2100Z-210714T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Northwest Plateau-Lake Havasu and Fort Mohave-Northwest Deserts-Lake Mead National Recreation Area-San Bernardino County-Upper Colorado River Valley-Northeast Clark County-Lake Mead National Recreation Area- Including the cities of Western Grand Canyon, Laughlin, Lake Havasu City, Colorado City, Yucca, Desert Hills, Needles, Wikieup, Mesquite, Bullhead City, Golden Valley, Mt Trumbull, Oatman, Topock, Overton, Tuweep, Hoover Dam, Mohave Valley, Pipe Spring National Monument, Valentine, Moapa, Dolan Springs, and Kingman 111 PM MST Mon Jul 12 2021 /111 PM PDT Mon Jul 12 2021/ ...FLASH FLOOD WATCH IN EFFECT FROM TUESDAY AFTERNOON THROUGH LATE TUESDAY NIGHT... The National Weather Service in Las Vegas has issued a * Flash Flood Watch for portions of northwest Arizona, southeast California and southern Nevada, including the following areas, in northwest Arizona, Lake Havasu and Fort Mohave, Lake Mead National Recreation Area, Northwest Deserts and Northwest Plateau. In southeast California, San Bernardino County-Upper Colorado River Valley. In southern Nevada, Lake Mead National Recreation Area and Northeast Clark County. * From Tuesday afternoon through late Tuesday night. * The potential for heavy rainfall and flash flooding exists late Tuesday afternoon through the overnight hours as thunderstorms move south across eastern Clark County, Mohave County and the lower Colorado River Valley. Rainfall rates of 1 to 1.5 inches an hour are possible. PRECAUTIONARY/PREPAREDNESS ACTIONS... Turn around, don't drown when encountering flooded roads. Most flood deaths occur in vehicles. A Flash Flood Watch means that conditions may become favorable for flashing flooding of recent burn areas. In steep terrain, the rainfall could trigger debris flows and rockfalls. Be prepared to take immediate action should rainfall trigger flash flooding. && $$ BKP
3 follow-up statements
217 WGUS65 KVEF 131056 FFAVEF Flood Watch National Weather Service Las Vegas NV 356 AM PDT Tue Jul 13 2021 AZZ001>003-036-CAZ527-NVZ016-021-132100- /O.CON.KVEF.FF.A.0001.210713T2100Z-210714T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Northwest Plateau-Lake Havasu and Fort Mohave-Northwest Deserts-Lake Mead National Recreation Area-San Bernardino County-Upper Colorado River Valley-Northeast Clark County-Lake Mead National Recreation Area- Including the cities of Western Grand Canyon, Laughlin, Lake Havasu City, Colorado City, Yucca, Desert Hills, Needles, Wikieup, Mesquite, Bullhead City, Golden Valley, Mt Trumbull, Oatman, Topock, Overton, Tuweep, Hoover Dam, Mohave Valley, Pipe Spring National Monument, Valentine, Moapa, Dolan Springs, and Kingman 356 AM MST Tue Jul 13 2021 /356 AM PDT Tue Jul 13 2021/ ...FLASH FLOOD WATCH REMAINS IN EFFECT FROM 2 PM MST /2 PM PDT/ THIS AFTERNOON THROUGH LATE TONIGHT... The Flash Flood Watch continues for * Portions of northwest Arizona, southeast California and southern Nevada, including the following areas, in northwest Arizona, Lake Havasu and Fort Mohave, Lake Mead National Recreation Area, Northwest Deserts and Northwest Plateau. In southeast California, San Bernardino County-Upper Colorado River Valley. In southern Nevada, Lake Mead National Recreation Area and Northeast Clark County. * From 2 PM MST /2 PM PDT/ this afternoon through late tonight. * The potential for heavy rainfall and flash flooding exists late this afternoon through the overnight hours as thunderstorms move south across eastern Clark County, Mohave County and the lower Colorado River Valley. Rainfall rates of 1 to 1.5 inches an hour are possible. * In addition to flash flooding of washes and roadways in the watch area, debris flows will be possible near the Flag Fire burn scar including the community of Pine Lake. PRECAUTIONARY/PREPAREDNESS ACTIONS... Turn around, don't drown when encountering flooded roads. Most flood deaths occur in vehicles. A Flash Flood Watch means that conditions may become favorable for flashing flooding of recent burn areas. In steep terrain, the rainfall could trigger debris flows and rockfalls. Be prepared to take immediate action should rainfall trigger flash flooding. && $$ TB3
036 WGUS65 KVEF 132033 FFAVEF Flood Watch National Weather Service Las Vegas NV 133 PM PDT Tue Jul 13 2021 AZZ001>003-036-CAZ527-NVZ016-021-141200- /O.CON.KVEF.FF.A.0001.210713T2100Z-210714T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Northwest Plateau-Lake Havasu and Fort Mohave-Northwest Deserts-Lake Mead National Recreation Area-San Bernardino County-Upper Colorado River Valley-Northeast Clark County-Lake Mead National Recreation Area- Including the cities of Western Grand Canyon, Laughlin, Lake Havasu City, Colorado City, Yucca, Desert Hills, Needles, Wikieup, Mesquite, Bullhead City, Golden Valley, Mt Trumbull, Oatman, Topock, Overton, Tuweep, Hoover Dam, Mohave Valley, Pipe Spring National Monument, Valentine, Moapa, Dolan Springs, and Kingman 133 PM MST Tue Jul 13 2021 /133 PM PDT Tue Jul 13 2021/ ...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH LATE TONIGHT... The Flash Flood Watch continues for * Portions of northwest Arizona, southeast California and southern Nevada, including the following areas, in northwest Arizona, Lake Havasu and Fort Mohave, Lake Mead National Recreation Area, Northwest Deserts and Northwest Plateau. In southeast California, San Bernardino County-Upper Colorado River Valley. In southern Nevada, Lake Mead National Recreation Area and Northeast Clark County. * Through late tonight. * The potential for heavy rainfall and flash flooding exists late this afternoon through the overnight hours as thunderstorms move south across eastern Clark County, Mohave County and the lower Colorado River Valley. Rainfall rates of 1 to 1.5 inches an hour are possible. * In addition to flash flooding of washes and roadways in the watch area, debris flows will be possible near the Flag Fire burn scar including the community of Pine Lake. PRECAUTIONARY/PREPAREDNESS ACTIONS... Turn around, don't drown when encountering flooded roads. Most flood deaths occur in vehicles. A Flash Flood Watch means that conditions may become favorable for flashing flooding of recent burn areas. In steep terrain, the rainfall could trigger debris flows and rockfalls. Be prepared to take immediate action should rainfall trigger flash flooding. && $$ BP
925 WGUS65 KVEF 141138 FFAVEF Flood Watch National Weather Service Las Vegas NV 438 AM PDT Wed Jul 14 2021 AZZ001>003-036-CAZ527-NVZ016-021-141245- /O.EXP.KVEF.FF.A.0001.000000T0000Z-210714T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Northwest Plateau-Lake Havasu and Fort Mohave-Northwest Deserts-Lake Mead National Recreation Area-San Bernardino County-Upper Colorado River Valley-Northeast Clark County-Lake Mead National Recreation Area- Including the cities of Western Grand Canyon, Laughlin, Lake Havasu City, Colorado City, Yucca, Desert Hills, Needles, Wikieup, Mesquite, Bullhead City, Golden Valley, Mt Trumbull, Oatman, Topock, Overton, Tuweep, Hoover Dam, Mohave Valley, Pipe Spring National Monument, Valentine, Moapa, Dolan Springs, and Kingman 438 AM MST Wed Jul 14 2021 /438 AM PDT Wed Jul 14 2021/ ...FLASH FLOOD WATCH WILL EXPIRE AT 5 AM MST/5 AM PDT/ EARLY THIS MORNING... The Flash Flood Watch for portions of northwest Arizona, southeast California and southern Nevada, including the following areas, in northwest Arizona, Lake Havasu and Fort Mohave, Lake Mead National Recreation Area, Northwest Deserts and Northwest Plateau. In southeast California, San Bernardino County-Upper Colorado River Valley. In southern Nevada, Lake Mead National Recreation Area and Northeast Clark County will expire at 5 AM PDT/5 AM MST/ early this morning. The Flash Flood Watch will be allowed to expire. Flooding is no longer expected to pose a threat. Please continue to heed remaining road closures. $$ DB
The office that day
Everything else NWS Las Vegas, NV issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 11, 10:58 PM MST | Flash Flood Warning | VEF | Mohave | 3 hr |
| Jul 11, 10:10 PM MST | Flash Flood Warning | VEF | Clark | 3 hr |
Nearby
Flash Flood Watches in Arizona, 2021Flash Flood Watches in Nevada, 2021Flash Flood Watches in California, 2021Every flash flood watch in 2021
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.