Alert archive / California / Flash Flood Warnings in 2026
Flash Flood Warning 21, NWS Las Vegas, NV
NWS Las Vegas, NV issued this flash flood warning at Aug 11, 2026, 6:46 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
- Aug 11, 2026, 6:46 PM PDT (01:46 UTC)
- Expired
- Aug 11, 2026, 9:45 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), 80 km from the middle of the area, began a volume at 01:45 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
San Diego, CA (KNKX), launched 00:00Z, 1.8 hours before the alert went out and 313 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
- 1843 m above ground
- 0-6 km bulk shear
- 6 kt
- 0-1 km storm-relative helicity
- -5 m²/s²
- 0-3 km storm-relative helicity
- 8 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
555
WGUS55 KVEF 120146
FFWVEF
CAC071-120445-
/O.NEW.KVEF.FF.W.0021.260812T0146Z-260812T0445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Las Vegas NV
646 PM PDT Tue Aug 11 2026
The National Weather Service in Las Vegas has issued a
* Flash Flood Warning for...
San Bernardino County in southern California...
* Until 945 PM PDT.
* At 646 PM PDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Between 1 and 1.5 inches of rain
have fallen. Additional rainfall amounts of 0.5 to 1 inch are
possible in the warned area. Flash flooding is ongoing or expected
to begin shortly.
HAZARD...Life threatening flash flooding. Thunderstorms producing
flash flooding.
SOURCE...Radar indicated.
IMPACT...Life threatening flash flooding of creeks and streams,
urban areas, highways, streets and underpasses.
* Some locations that will experience flash flooding include...
Cima, Kelso and Mountain Pass.
This includes Interstate 15 in California between mile markers 158
and 175.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.
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 3548 11559 3542 11577 3521 11570 3497 11576
3498 11543 3547 11548
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
JP2 follow-up statements
507
WGUS75 KVEF 120317
FFSVEF
Flash Flood Statement
National Weather Service Las Vegas NV
817 PM PDT Tue Aug 11 2026
CAC071-120445-
/O.CON.KVEF.FF.W.0021.000000T0000Z-260812T0445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Bernardino CA-
817 PM PDT Tue Aug 11 2026
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 945 PM PDT THIS
EVENING FOR SAN BERNARDINO COUNTY...
At 817 PM PDT, Doppler radar indicated thunderstorms producing heavy
rain across the warned area. Between 1 and 1.5 inches of rain have
fallen. Additional rainfall amounts up to 0.25 inches are possible in
the warned area. Flash flooding is ongoing or expected to begin
shortly.
HAZARD...Life threatening flash flooding. Thunderstorms producing
flash flooding.
SOURCE...Radar indicated.
IMPACT...Life threatening flash flooding of creeks and streams, urban
areas, highways, streets and underpasses.
Some locations that will experience flash flooding include...
Cima, Kelso and Mountain Pass.
This includes Interstate 15 in California between mile markers 158
and 175.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Be especially cautious at night when it is harder to recognize the
dangers of flooding.
In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.
Please report observed flooding to local emergency services or law
enforcement and request they pass this information to the National
Weather Service when you can do so safely.
&&
LAT...LON 3548 11559 3542 11577 3521 11570 3497 11576
3498 11543 3547 11548
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
JP914
WGUS75 KVEF 120441
FFSVEF
Flash Flood Statement
National Weather Service Las Vegas NV
941 PM PDT Tue Aug 11 2026
CAC071-120451-
/O.EXP.KVEF.FF.W.0021.000000T0000Z-260812T0445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Bernardino CA-
941 PM PDT Tue Aug 11 2026
...FLASH FLOOD WARNING WILL EXPIRE AT 945 PM PDT THIS EVENING FOR SAN
BERNARDINO COUNTY...
The heavy rain has ended. Flood waters have receded. Flooding is no
longer expected to pose a threat. Please continue to heed remaining
road closures.
&&
LAT...LON 3548 11559 3542 11577 3521 11570 3497 11576
3498 11543 3547 11548
$$
JPThe office that day
Everything else NWS Las Vegas, NV issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 11, 5:42 PM PDT | Severe Thunderstorm Warning | VEF | San Bernardino | 48 min |
| Aug 11, 6:26 PM PDT | Areal Flood Warning | VEF | San Bernardino | 3 hr |
| Aug 11, 6:54 PM PDT | Severe Thunderstorm Warning | VEF | San Bernardino | 51 min |
| Aug 12, 1:55 PM PDT | Flash Flood Warning | VEF | San Bernardino | 3 hr |
| Aug 12, 2:53 PM PDT | Severe Thunderstorm Warning | VEF | San Bernardino | 52 min |
| Aug 12, 3:30 PM PDT | Areal Flood Advisory | VEF | San Bernardino | 30 min |
| Aug 12, 3:58 PM PDT | Severe Thunderstorm Warning | VEF | San Bernardino | 47 min |
| Aug 12, 4:00 PM PDT | Flash Flood Warning | VEF | San Bernardino | 4 hr |
Nearby
Flash Flood Warnings in California, 2026Every flash flood warning in 2026
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.