Alert archive / California / Flash Flood Warnings in 2021
Flash Flood Warning 13, NWS San Diego, CA
NWS San Diego, CA issued this flash flood warning at Sep 9, 2021, 2:34 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
- Sep 9, 2021, 2:34 PM PDT (21:34 UTC)
- Expired
- Sep 9, 2021, 5:45 PM PDT
- In force
- 3 hr
- Issued by
- NWS San Diego, CA
- Area
- Storm-based polygon
- Damage threat
- Considerable
- Flood severity
- None
County San Bernardino County, CA
The radar
The Santa Ana Mts radar (KSOX), 76 km from the middle of the area, began a volume at 21:35 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, 9.6 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
- 15 J/kg
- Mixed-layer CIN
- -787 J/kg
- Mixed-layer LCL
- 1710 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 44 m²/s²
- 0-3 km storm-relative helicity
- 112 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
The text
As transmitted.
999
WGUS56 KSGX 092134
FFWSGX
CAC071-100045-
/O.NEW.KSGX.FF.W.0013.210909T2134Z-210910T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service San Diego CA
234 PM PDT Thu Sep 9 2021
The National Weather Service in San Diego has issued a
* Flash Flood Warning for...
San Bernardino County in southern California...
* Until 545 PM PDT.
* At 234 PM PDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Between 0.5 and 1.5 inches of
rain have fallen. 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...
Lake Arrowhead, Running Springs, Hwy 18 Between Running Springs
And Big Bear, Hwy 18 Between Running Springs And Skyforest, Green
Valley Lake, Cedar Glen and Fawnskin.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 3439 11719 3440 11717 3438 11714 3440 11708
3440 11705 3432 11695 3422 11690 3412 11704
3425 11717
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
Brotherton2 follow-up statements
350
WGUS76 KSGX 092253
FFSSGX
Flash Flood Statement
National Weather Service San Diego CA
353 PM PDT Thu Sep 9 2021
CAC071-100045-
/O.CON.KSGX.FF.W.0013.000000T0000Z-210910T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Bernardino CA-
353 PM PDT Thu Sep 9 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 545 PM PDT THIS
AFTERNOON FOR SAN BERNARDINO COUNTY...
At 353 PM PDT, Doppler radar indicated thunderstorms producing heavy
rain across the warned area. Additional rainfall amounts of 0.5 to 1
inch are possible in the warned area. Flash flooding is ongoing or
expected to begin shortly.
HAZARD...Life threatening flash flooding. Thunderstorms producing
flash flooding.
SOURCE...Radar.
IMPACT...Life threatening flash flooding of creeks and streams,
urban areas, highways, streets and underpasses.
Some locations that will experience flash flooding include...
Apple Valley, Lake Arrowhead, Lucerne Valley, Big Bear Lake,
Running Springs, Hwy 18 Between Running Springs And Big Bear, Hwy
18 Between Running Springs And Skyforest, Green Valley Lake, Cedar
Glen and Fawnskin.
Highway 18 is closed due to earlier flooding and additional rains
will exacerbate ongoing issues.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Be aware of your surroundings and do not drive on flooded roads.
&&
LAT...LON 3439 11719 3440 11717 3438 11714 3440 11708
3440 11705 3432 11695 3422 11690 3412 11704
3425 11717
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
Brotherton446
WGUS76 KSGX 100040
FFSSGX
Flash Flood Statement
National Weather Service San Diego CA
540 PM PDT Thu Sep 9 2021
CAC071-100050-
/O.EXP.KSGX.FF.W.0013.000000T0000Z-210910T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Bernardino CA-
540 PM PDT Thu Sep 9 2021
...FLASH FLOOD WARNING WILL EXPIRE AT 545 PM PDT THIS AFTERNOON FOR
SAN BERNARDINO COUNTY...
The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed remaining road closures.
LAT...LON 3439 11719 3440 11717 3438 11714 3440 11708
3440 11705 3432 11695 3422 11690 3412 11704
3425 11717
$$
BrothertonThe office that day
Everything else NWS San Diego, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 9, 12:40 PM PDT | Special Weather Statement | SGX | 50 min | |
| Sep 9, 1:05 PM PDT | Severe Thunderstorm Warning | SGX | San Bernardino | 40 min |
| Sep 9, 1:19 PM PDT | Severe Thunderstorm Warning | SGX | San Bernardino | 22 min |
| Sep 9, 2:12 PM PDT | Areal Flood Advisory | SGX | San Diego | 3 hr |
| Sep 9, 2:54 PM PDT | Severe Thunderstorm Warning | SGX | San Bernardino | 66 min |
| Sep 9, 3:10 PM PDT | Severe Thunderstorm Warning | SGX | Riverside, San Bernardino | 50 min |
| Sep 9, 3:25 PM PDT | Special Weather Statement | SGX | 50 min | |
| Sep 9, 3:29 PM PDT | Flash Flood Warning | SGX | Riverside, San Bernardino | 2 hr |
| Sep 9, 3:46 PM PDT | Areal Flood Advisory | SGX | Riverside | 3 hr |
| Sep 9, 4:33 PM PDT | Flash Flood Warning | SGX | Riverside | 88 min |
| Sep 9, 4:35 PM PDT | Severe Thunderstorm Warning | SGX | Riverside, San Bernardino | 55 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.