Alert archive / California / Flash Flood Warnings in 2021
Flash Flood Warning 46, NWS Las Vegas, NV
NWS Las Vegas, NV issued this flash flood warning at Jul 21, 2021, 4:38 PM PDT for San Bernardino County, California. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.
The area
The outline as issued.
The facts
- Issued
- Jul 21, 2021, 4:38 PM PDT (23:38 UTC)
- Expired
- Jul 21, 2021, 7:45 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 Las Vegas radar (KESX), 85 km from the middle of the area, began a volume at 23:42 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, 11.6 hours before the alert went out and 170 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
- 113 J/kg
- Mixed-layer CIN
- -279 J/kg
- Mixed-layer LCL
- 2504 m above ground
- 0-6 km bulk shear
- 16 kt
- 0-1 km storm-relative helicity
- 34 m²/s²
- 0-3 km storm-relative helicity
- 19 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
658
WGUS55 KVEF 212338
FFWVEF
CAC071-220245-
/O.NEW.KVEF.FF.W.0046.210721T2338Z-210722T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Las Vegas NV
438 PM PDT Wed Jul 21 2021
The National Weather Service in Las Vegas has issued a
* Flash Flood Warning for...
San Bernardino County in southern California...
* Until 745 PM PDT.
* At 438 PM PDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. 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...
mainly rural areas of San Bernardino County including Goffs Road.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Please report observed flooding to local emergency services or law
enforcement and request they pass this information to the National
Weather Service when you can do so safely.
&&
LAT...LON 3496 11484 3494 11482 3490 11493 3494 11496
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
AN2 follow-up statements
936
WGUS75 KVEF 220114
FFSVEF
Flash Flood Statement
National Weather Service Las Vegas NV
614 PM PDT Wed Jul 21 2021
CAC071-220245-
/O.CON.KVEF.FF.W.0046.000000T0000Z-210722T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Bernardino CA-
614 PM PDT Wed Jul 21 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 745 PM PDT THIS
EVENING FOR SAN BERNARDINO COUNTY...
At 614 PM PDT, Doppler radar indicated heavy rain has ended across
the warned area. However, additional thunderstorm development is
occurring south of the area. Thus the flash flood threat will
continue.
HAZARD...Thunderstorms producing flash flooding over Goffs Road.
SOURCE...Radar.
IMPACT...Life-threatening flash flooding of low-water crossings,
creeks, normally dry washes and roads.
Some locations that will experience flash flooding include...
mainly rural areas of San Bernardino County including Goffs Road.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Please report observed flooding to local emergency services or law
enforcement and request they pass this information to the National
Weather Service when you can do so safely.
&&
LAT...LON 3496 11484 3494 11482 3490 11493 3494 11496
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
TB605 WGUS75 KVEF 220240 FFSVEF Flash Flood Statement National Weather Service Las Vegas NV 740 PM PDT Wed Jul 21 2021 CAC071-220250- /O.EXP.KVEF.FF.W.0046.000000T0000Z-210722T0245Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ San Bernardino CA- 740 PM PDT Wed Jul 21 2021 ...FLASH FLOOD WARNING WILL EXPIRE AT 745 PM PDT THIS EVENING FOR SAN BERNARDINO COUNTY... The heavy rain has ended for the area including Goffs Road. Flooding is no longer expected to pose a threat. Please continue to heed remaining road closures. LAT...LON 3496 11484 3494 11482 3490 11493 3494 11496 $$ TB
The office that day
Everything else NWS Las Vegas, NV issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 20, 6:27 PM PDT | Flash Flood Warning | VEF | San Bernardino | 3 hr |
| Jul 21, 12:13 PM PDT | Flash Flood Warning | VEF | San Bernardino | 3 hr |
| Jul 21, 3:07 PM PDT | Flash Flood Warning | VEF | San Bernardino | 2 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.