Alert archive / California / Flash Flood Warnings in 2021
Flash Flood Warning 119, NWS Las Vegas, NV
NWS Las Vegas, NV issued this flash flood warning at Aug 29, 2021, 6:53 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 29, 2021, 6:53 PM PDT (01:53 UTC)
- Expired
- Aug 29, 2021, 10:00 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 Las Vegas radar (KESX), 130 km from the middle of the area, began a volume at 01:56 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 29, 7:21 PM PDT | FLASH FLOOD | 14 S Needles, CA | LAW ENFORCEMENT REPORTED 30 LOW WATER CROSSINGS ALONG US 95 FROM HAVASU LAKE ROAD NORTH TO NEEDLES COVERED IN MUD AND DEBRIS WHICH WILL REQUIRE A BLADE TRUCK. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Las Vegas, NV (KVEF), launched 00:00Z, 1.9 hours before the alert went out and 220 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
- 421 J/kg
- Mixed-layer CIN
- -6 J/kg
- Mixed-layer LCL
- 3881 m above ground
- 0-6 km bulk shear
- 5 kt
- 0-1 km storm-relative helicity
- -15 m²/s²
- 0-3 km storm-relative helicity
- 71 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
079
WGUS55 KVEF 300153
FFWVEF
CAC071-300500-
/O.NEW.KVEF.FF.W.0119.210830T0153Z-210830T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Las Vegas NV
653 PM PDT Sun Aug 29 2021
The National Weather Service in Las Vegas has issued a
* Flash Flood Warning for...
San Bernardino County in southern California...
* Until 1000 PM PDT.
* At 653 PM PDT, Doppler radar indicated thunderstorms producing
heavy rain in Chemehuevi Wash. Flash flooding is ongoing or
expected to begin shortly.
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...
Highway 95 At Mile Marker 29 and Needles.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 3452 11486 3463 11485 3469 11481 3478 11479
3481 11466 3480 11462 3477 11456 3471 11447
3466 11446 3461 11442 3459 11443 3453 11438
3446 11439 3445 11437 3445 11434 3443 11431
3436 11433 3435 11443 3436 11469 3439 11478
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
BKP2 follow-up statements
154
WGUS75 KVEF 300313
FFSVEF
Flash Flood Statement
National Weather Service Las Vegas NV
813 PM PDT Sun Aug 29 2021
CAC071-300500-
/O.CON.KVEF.FF.W.0119.000000T0000Z-210830T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Bernardino CA-
813 PM PDT Sun Aug 29 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 10 PM PDT THIS
EVENING FOR SAN BERNARDINO COUNTY...
At 813 PM PDT, California Highway Patrol reported water and debris
across numerous sections of road from Havasu Lake Road north to
Needles. Flash flooding is ongoing. Highway 95 near mile marker 29
will be especially prone to flooding where the Chemehuevi Wash
crosses the road.
HAZARD...Life-threatening flash flooding. Thunderstorms producing
flash flooding.
SOURCE...Law enforcement reported.
IMPACT...Life-threatening flash flooding of low-water crossings,
normally dry washes and roads.
Some locations that will experience flash flooding include...
Havasu Lake Road and Highway 95 south of Needles especially near
mile marker 29.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 3452 11486 3463 11485 3469 11481 3478 11479
3481 11466 3480 11462 3477 11456 3471 11447
3466 11446 3461 11442 3459 11443 3453 11438
3446 11439 3445 11437 3445 11434 3443 11431
3436 11433 3435 11443 3436 11469 3439 11478
FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
JA615
WGUS75 KVEF 300458
FFSVEF
Flash Flood Statement
National Weather Service Las Vegas NV
958 PM PDT Sun Aug 29 2021
CAC071-300508-
/O.EXP.KVEF.FF.W.0119.000000T0000Z-210830T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Bernardino CA-
958 PM PDT Sun Aug 29 2021
...FLASH FLOOD WARNING WILL EXPIRE AT 10 PM PDT THIS EVENING FOR SAN
BERNARDINO COUNTY...
Flood waters have likely receded along Highway 95 south of Needles
and Havasu Lake Road. Flooding is no longer expected to pose a
threat. Please continue to heed remaining road closures and drive
with caution for any water in low spots.
LAT...LON 3452 11486 3463 11485 3469 11481 3478 11479
3481 11466 3480 11462 3477 11456 3471 11447
3466 11446 3461 11442 3459 11443 3453 11438
3446 11439 3445 11437 3445 11434 3443 11431
3436 11433 3435 11443 3436 11469 3439 11478
$$
JAThe office that day
Everything else NWS Las Vegas, NV issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 30, 3:28 AM PDT | Flash Flood Watch | VEF | San Bernardino | 59 hr |
| Aug 30, 1:17 PM PDT | Flash Flood Warning | VEF | San Bernardino | 3 hr |
| Aug 30, 2:37 PM PDT | Flash Flood Warning | VEF | San Bernardino | 3 hr |
| Aug 30, 2:55 PM PDT | Flash Flood Warning | 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.