Alert archive / California / Flash Flood Warnings in 2021
Flash Flood Warning 4, NWS San Diego, CA
NWS San Diego, CA issued this flash flood warning at Jul 22, 2021, 4:23 PM PDT for Riverside County, California. It was in force for 2 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 22, 2021, 4:23 PM PDT (23:23 UTC)
- Expired
- Jul 22, 2021, 6:38 PM PDT
- In force
- 2 hr
- Issued by
- NWS San Diego, CA
- Area
- Storm-based polygon
- Damage threat
- Considerable
- Flood severity
- None
County Riverside County, CA
The radar
The San Diego radar (KNKX), 96 km from the middle of the area, began a volume at 23:22 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 12:00Z, 11.4 hours before the alert went out and 115 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
- 1541 m above ground
- 0-6 km bulk shear
- 10 kt
- 0-1 km storm-relative helicity
- -16 m²/s²
- 0-3 km storm-relative helicity
- -8 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
346
WGUS56 KSGX 222323
FFWSGX
CAC065-230230-
/O.NEW.KSGX.FF.W.0004.210722T2323Z-210723T0230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service San Diego CA
423 PM PDT Thu Jul 22 2021
The National Weather Service in San Diego has issued a
* Flash Flood Warning for...
Riverside County in southern California...
* Until 730 PM PDT.
* At 423 PM PDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. The expected rainfall rate is 1
to 2 inches in 1 hour. Additional rainfall amounts of 1 to 2
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.
IMPACT...Life threatening flash flooding of creeks and streams,
urban areas, highways, streets and underpasses.
* Some locations that will experience flash flooding include...
Southeastern Palm Springs, eastern Anza, Palm Desert, Hwy 74
Between Anza And Palm Desert, Hwy 74 Between Mountain Center And
Anza and Santa Rosa Mountain.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 3371 11643 3360 11636 3347 11658 3371 11661
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
EXPECTED RAINFALL...1-2 INCHES IN 1 HOUR
$$
Small2 follow-up statements
052
WGUS76 KSGX 230002
FFSSGX
Flash Flood Statement
National Weather Service San Diego CA
502 PM PDT Thu Jul 22 2021
CAC065-230230-
/O.CON.KSGX.FF.W.0004.000000T0000Z-210723T0230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Riverside CA-
502 PM PDT Thu Jul 22 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 730 PM PDT THIS
EVENING FOR RIVERSIDE COUNTY...
At 502 PM PDT, Doppler radar indicated thunderstorms producing heavy
rain across the warned area. Additional rainfall amounts of 0.5 to
1.25 inches are possible in the warned area. Flash flooding is
ongoing or expected to begin shortly. About 1.14 inches of rain has
been reported so far in the warning area.
HAZARD...Life threatening flash flooding. Thunderstorms producing
flash flooding.
SOURCE...Radar.
IMPACT...Life threatening flash flooding of creeks and streams,
urban areas, highways, streets and underpasses.
Some locations that will experience flash flooding include...
Southeastern Palm Springs, eastern Anza, Palm Desert, Hwy 74
Between Anza And Palm Desert, Hwy 74 Between Mountain Center And
Anza and Santa Rosa Mountain.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Be aware of your surroundings and do not drive on flooded roads.
&&
LAT...LON 3371 11643 3360 11636 3347 11658 3371 11661
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
Small850 WGUS76 KSGX 230138 FFSSGX Flash Flood Statement National Weather Service San Diego CA 638 PM PDT Thu Jul 22 2021 CAC065-230148- /O.CAN.KSGX.FF.W.0004.000000T0000Z-210723T0230Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Riverside CA- 638 PM PDT Thu Jul 22 2021 ...FLASH FLOOD WARNING IS CANCELLED FOR RIVERSIDE COUNTY... The heavy rain has ended, so flooding is no longer expected to pose a threat. Please continue to heed remaining road closures. LAT...LON 3371 11643 3360 11636 3347 11658 3371 11661 $$ Small
The office that day
Everything else NWS San Diego, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 22, 3:45 PM PDT | Flash Flood Warning | SGX | San Diego | 2 hr |
| Jul 22, 4:18 PM PDT | Flash Flood Warning | SGX | San Diego | 117 min |
| Jul 22, 4:22 PM PDT | Severe Thunderstorm Warning | SGX | San Diego | 53 min |
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.