Alert archive / California / Flash Flood Warnings in 2026
Flash Flood Warning 17, NWS Las Vegas, NV
NWS Las Vegas, NV issued this flash flood warning at Aug 11, 2026, 3:26 PM PDT for San Bernardino County, California. It was in force for 3 hr. 2 reports 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 11, 2026, 3:26 PM PDT (22:26 UTC)
- Expired
- Aug 11, 2026, 6:30 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 Edwards AFB radar (KEYX), 62 km from the middle of the area, began a volume at 22:26 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 11, 3:42 PM PDT | FLASH FLOOD | 3 Ne Nebo Center, CA | Social media photos show water flowing across Fort Irwin Rd at I-15 with cars stuck in water. |
| Aug 11, 3:42 PM PDT | FLASH FLOOD | 3 Ne Nebo Center, CA | Social media photos show water flowing across Fort Irwin Rd at I-15 with cars stuck in water. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
Did it verify
Verified. The Iowa Environmental Mesonet's Cow matched one storm report to this flash flood warning; the first came 16 minutes after it went out.
Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.
The nearest sounding before it
Las Vegas, NV (KVEF), launched 12:00Z, 10.4 hours before the alert went out and 203 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
- 5 J/kg
- Mixed-layer CIN
- -300 J/kg
- Mixed-layer LCL
- 3285 m above ground
- 0-6 km bulk shear
- 8 kt
- 0-1 km storm-relative helicity
- 3 m²/s²
- 0-3 km storm-relative helicity
- 5 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
871
WGUS55 KVEF 112226
FFWVEF
CAC071-120130-
/O.NEW.KVEF.FF.W.0017.260811T2226Z-260812T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Las Vegas NV
326 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 630 PM PDT.
* At 326 PM PDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Between 1 and 2 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...
Daggett and Nebo Center.
This includes the following highways...
Interstate 15 in California between mile markers 81 and 89.
Interstate 40 in California between mile markers 2 and 11.
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 3498 11704 3486 11698 3484 11687 3485 11677
3497 11676 3502 11693
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
JP2 follow-up statements
629
WGUS75 KVEF 112302
FFSVEF
Flash Flood Statement
National Weather Service Las Vegas NV
402 PM PDT Tue Aug 11 2026
CAC071-120130-
/O.CON.KVEF.FF.W.0017.000000T0000Z-260812T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Bernardino CA-
402 PM PDT Tue Aug 11 2026
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 630 PM PDT THIS
EVENING FOR SAN BERNARDINO COUNTY...
At 402 PM PDT, Public has reported significant flooding along I-15
near Fort Irwin Road in Barstow. Between 1.5 and 2.5 inches of rain
have fallen. Additional rainfall amounts of 0.5 to 1 inch are
possible in the warned area. Flash flooding is already occurring.
HAZARD...Life threatening flash flooding. Thunderstorms producing
flash flooding.
SOURCE...Public reported flash flooding, radar indicated rainfall.
IMPACT...Life threatening flash flooding of creeks and streams, urban
areas, highways, streets and underpasses.
Some locations that will experience flash flooding include...
Daggett and Nebo Center.
This includes the following highways...
Interstate 15 in California between mile markers 81 and 89.
Interstate 40 in California between mile markers 2 and 11.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.
Please report observed flooding to local emergency services or law
enforcement and request they pass this information to the National
Weather Service when you can do so safely.
&&
LAT...LON 3498 11704 3486 11698 3484 11687 3485 11677
3497 11676 3502 11693
FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
JP054
WGUS75 KVEF 120126
FFSVEF
Flash Flood Statement
National Weather Service Las Vegas NV
626 PM PDT Tue Aug 11 2026
CAC071-120136-
/O.EXP.KVEF.FF.W.0017.000000T0000Z-260812T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Bernardino CA-
626 PM PDT Tue Aug 11 2026
...FLASH FLOOD WARNING WILL EXPIRE AT 630 PM PDT THIS EVENING FOR SAN
BERNARDINO COUNTY...
This Flash Flood Warning has been replaced with a Flood Warning.
Please continue to heed any remaining road closures.
&&
LAT...LON 3498 11704 3486 11698 3484 11687 3485 11677
3497 11676 3502 11693
$$
JPWhat forecasters said that day
The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Las Vegas, NV wrote its last area forecast discussion before this flash flood warning went out at Aug 11, 12:45 PM PDT, 2 hours 41 minutes earlier. Its key messages:
- * Daily afternoon to evening isolated thunderstorm chances will continue through the week, with the greatest chances over higher terrain and some storms spreading into adjacent valleys. Storm chances will increase in the mid week. * The high pressure is pushing eastward leading to cooling temperatures through the week.
Area forecast discussion, Aug 11, 12:45 PM PDT, 2 hours 41 minutes before
Area Forecast Discussion National Weather Service Las Vegas NV 1245 PM PDT Tue Aug 11 2026 .KEY MESSAGES... * Daily afternoon to evening isolated thunderstorm chances will continue through the week, with the greatest chances over higher terrain and some storms spreading into adjacent valleys. Storm chances will increase in the mid week. * The high pressure is pushing eastward leading to cooling temperatures through the week. && .DISCUSSION... Monsoonal moisture will remain in place through the end of the week with the deepest moisture generally located over the southern half of the forecast area with PWATs of 1.00-1.50" across Lincoln, Clark, southern Nye, eastern San Bernardino, and Mohave counties. Areas to the north and west will generally remain around 0.75-1.00". Storm chances are expected to increase over most areas as we start to see more influence from trough located offshore. This will increase shear and some cooling aloft. This combined with decent instability areawide should lead to a better coverage of storms at least through Thursday afternoon. Storms will still be hit and miss, but overall coverage will increase. With the high PWs, flash flooding will remain a concern along with strong gusty outflow winds along with small hail. By Thursday and especially Friday into the weekend, the trough offshore will begin to push inland. This will bring a drier southwest flow into the region ending shower and thunderstorm chances from west to east with only the far eastern areas of the forecast area seeing thunderstorm chances over the weekend. While the exiting high pressure will allow for more convection over the next few days, it will also call for a cooling trend through the end of the work week. Heat risk will drop through the week with all of the southern Great Basin and Mojave Desert seeing only Minor or Moderate readings. Lows look to fall into the 70s and 80s while highs reduce into the 90s to lower 100s. Temperatures look to rebound slightly into the weekend, but not significantly. && .AVIATION...For Harry Reid...For the 18Z Forecast Package...Somewhat tricky afternoon forecast today in regard to thunderstorm chances. Given the latest satellite imagery and model runs, thinking cloud cover will limit instability in Vegas, keeping storms off to our southwest. However, confidence in this is moderate. There are a few model solutions that try to bring isolated storms into the southern valley in the late afternoon, but better chances exist tomorrow (~30%). Otherwise, breezy south winds continue, weakening after sunset. Cloud bases at or above 12kft. Temps above 100F between 18z and 03z. For the rest of southern Nevada, northwest Arizona and southeast California...For the 18Z Forecast Package...Scattered showers and isolated storms continue across central/eastern San Bernardino County and southern Mohave County this morning. Expecting this activity to wane over the coming hours, with additional development later today in areas to the west and north. Main concerns will be gusty outflow winds and localized downpours. Activity should begin to wane after sunset, but may start again early Wednesday morning across our far southeastern areas. Cloud bases at or above 10kft. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && DISCUSSION...Gorelow AVIATION...Woods For more forecast information...see us on our webpage: https://weather.gov/lasvegas or follow us on Facebook and Twitter
The office that day
Everything else NWS Las Vegas, NV issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 10, 5:02 PM PDT | Severe Thunderstorm Warning | VEF | San Bernardino | 43 min |
| Aug 10, 5:21 PM PDT | Areal Flood Advisory | VEF | San Bernardino | 3 hr |
| Aug 10, 6:05 PM PDT | Areal Flood Advisory | VEF | San Bernardino | 3 hr |
| Aug 10, 6:30 PM PDT | Areal Flood Advisory | VEF | San Bernardino | 3 hr |
| Aug 10, 6:52 PM PDT | Areal Flood Advisory | VEF | San Bernardino | 3 hr |
| Aug 10, 7:22 PM PDT | Flash Flood Warning | VEF | San Bernardino | 113 min |
| Aug 11, 2:14 PM PDT | Severe Thunderstorm Warning | VEF | San Bernardino | 46 min |
| Aug 11, 3:08 PM PDT | Areal Flood Advisory | VEF | San Bernardino | 3 hr |
| Aug 11, 3:36 PM PDT | Severe Thunderstorm Warning | VEF | San Bernardino | 39 min |
| Aug 11, 3:50 PM PDT | Severe Thunderstorm Warning | VEF | San Bernardino | 40 min |
| Aug 11, 4:12 PM PDT | Severe Thunderstorm Warning | VEF | San Bernardino | 48 min |
| Aug 11, 4:18 PM PDT | Flash Flood Warning | VEF | San Bernardino | 3 hr |
| Aug 11, 4:24 PM PDT | Flash Flood Warning | VEF | Inyo | 3 hr |
| Aug 11, 4:42 PM PDT | Flash Flood Warning | VEF | San Bernardino | 3 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.