Alert archive / California / Flash Flood Warnings in 2021
Flash Flood Warning 97, NWS Las Vegas, NV
NWS Las Vegas, NV issued this flash flood warning at Aug 9, 2021, 2:37 PM PDT for San Bernardino County, California. It was in force for 3 hr. 1 report came from inside the area while it was in force.
The area
The outline as issued, with what was reported inside it.
The facts
- Issued
- Aug 9, 2021, 2:37 PM PDT (21:37 UTC)
- Expired
- Aug 9, 2021, 5:45 PM PDT
- In force
- 3 hr
- Issued by
- NWS Las Vegas, NV
- Area
- Storm-based polygon
- Damage threat
- Considerable
- Flood severity
- None
County San Bernardino County, CA
The radar
The Santa Ana Mts radar (KSOX), 154 km from the middle of the area, began a volume at 21:39 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.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Aug 9, 3:41 PM PDT | FLASH FLOOD | 2 Sw Wonder Valley, CA | FLOODING ON CA-62 PER CHP WITH 2 FEET OF WATER FLOWING ACROSS THE ROAD. LARGE DEBRIS ALSO REPORTED ON THE THE ROAD. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
San Diego, CA (KNKX), launched 12:00Z, 9.6 hours before the alert went out and 182 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1565 m above ground
- 0-6 km bulk shear
- 6 kt
- 0-1 km storm-relative helicity
- 11 m²/s²
- 0-3 km storm-relative helicity
- 14 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
034
WGUS55 KVEF 092137
FFWVEF
CAC071-100045-
/O.NEW.KVEF.FF.W.0097.210809T2137Z-210810T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Las Vegas NV
237 PM PDT Mon Aug 9 2021
The National Weather Service in Las Vegas has issued a
* Flash Flood Warning for...
San Bernardino County in southern California...
* Until 545 PM PDT.
* At 237 PM PDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Between 0.5 and 1.25 inches of
rain have fallen. Flash flooding is ongoing or expected to begin
shortly around Twentynine palms and along Highway 62.
HAZARD...Life-threatening flash flooding. Thunderstorms
producing flash flooding.
SOURCE...Radar.
IMPACT...Life-threatening flash flooding of low-water
crossings, creeks, normally dry washes and roads.
* Some locations that will experience flash flooding include...
Twentynine Palms and Twentynine Palms Airport.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 3417 11609 3417 11596 3412 11577 3404 11579
3404 11584 3404 11592 3404 11593 3404 11596
3403 11599 3403 11600 3405 11600 3408 11600
3408 11604 3409 11604 3411 11604 3411 11605
3412 11605 3412 11609 3412 11611 3412 11614
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
CO3 follow-up statements
160
WGUS75 KVEF 092230
FFSVEF
Flash Flood Statement
National Weather Service Las Vegas NV
330 PM PDT Mon Aug 9 2021
CAC071-100045-
/O.CON.KVEF.FF.W.0097.000000T0000Z-210810T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Bernardino CA-
330 PM PDT Mon Aug 9 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 545 PM PDT THIS
AFTERNOON FOR SAN BERNARDINO COUNTY...
At 330 PM PDT, Thunderstorm activity continues to develop eastward
across Twentynine Palms and West Wind Aero. Reports of minor
flooding along area roadways has been received...particularly along
Highway 62 and Amboy Roads. Flash flooding remains possible through
this evening.
HAZARD...Life-threatening flash flooding. Thunderstorms producing
flash flooding.
SOURCE...Radar.
IMPACT...Life-threatening flash flooding of low-water crossings,
creeks, normally dry washes and roads.
Some locations that will experience flash flooding include...
Twentynine Palms and Twentynine Palms Airport.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 3417 11609 3417 11596 3412 11577 3404 11579
3404 11584 3404 11592 3404 11593 3404 11596
3403 11599 3403 11600 3405 11600 3408 11600
3408 11604 3409 11604 3411 11604 3411 11605
3412 11605 3412 11609 3412 11611 3412 11614
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
CO128
WGUS75 KVEF 092249
FFSVEF
Flash Flood Statement
National Weather Service Las Vegas NV
349 PM PDT Mon Aug 9 2021
CAC071-100045-
/O.CON.KVEF.FF.W.0097.000000T0000Z-210810T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Bernardino CA-
349 PM PDT Mon Aug 9 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 545 PM PDT THIS
AFTERNOON FOR SAN BERNARDINO COUNTY...
At 349 PM PDT, CHP has reported areas of severe flooding...
particularly on highway 62 near mile marker 42 east of Twentynine
Palms. Additional flooding is ongoing along low water crossings on
Amboy Road. Continue to heed road closures and avoid areas of water
drainage and low water crossings.
HAZARD...Life-threatening flash flooding. Thunderstorms producing
flash flooding.
SOURCE...Radar.
IMPACT...Life-threatening flash flooding of low-water crossings,
creeks, normally dry washes and roads.
Some locations that will experience flash flooding include...
Twentynine Palms and Twentynine Palms Airport.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 3417 11609 3417 11596 3412 11577 3404 11579
3404 11584 3404 11592 3404 11593 3404 11596
3403 11599 3403 11600 3405 11600 3408 11600
3408 11604 3409 11604 3411 11604 3411 11605
3412 11605 3412 11609 3412 11611 3412 11614
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
CO934
WGUS75 KVEF 100038
FFSVEF
Flash Flood Statement
National Weather Service Las Vegas NV
538 PM PDT Mon Aug 9 2021
CAC071-100048-
/O.EXP.KVEF.FF.W.0097.000000T0000Z-210810T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Bernardino CA-
538 PM PDT Mon Aug 9 2021
...FLASH FLOOD WARNING WILL EXPIRE AT 545 PM PDT THIS AFTERNOON FOR
SAN BERNARDINO COUNTY...
The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed remaining road closures.
LAT...LON 3417 11609 3417 11596 3412 11577 3404 11579
3404 11584 3404 11592 3404 11593 3404 11596
3403 11599 3403 11600 3405 11600 3408 11600
3408 11604 3409 11604 3411 11604 3411 11605
3412 11605 3412 11609 3412 11611 3412 11614
$$
COThe office that day
Everything else NWS Las Vegas, NV issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 9, 1:49 PM PDT | Areal Flood Advisory | VEF | San Bernardino | 3 hr |
Nearby
Flash Flood Warnings in California, 2021Every flash flood warning 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.