Alert archive / California / Flash Flood Warnings in 2021
Flash Flood Warning 230, NWS Phoenix, AZ
NWS Phoenix, AZ issued this flash flood warning at Aug 30, 2021, 5:14 PM PDT for Imperial County, Riverside County, California. It was in force for 4 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 30, 2021, 5:14 PM PDT (00:14 UTC)
- Expired
- Aug 30, 2021, 9:15 PM PDT
- In force
- 4 hr
- Issued by
- NWS Phoenix, AZ
- Area
- Storm-based polygon
- Damage threat
- Considerable
- Flood severity
- None
Counties Imperial County, CA, Riverside County, CA
The radar
The Yuma radar (KYUX), 123 km from the middle of the area, began a volume at 00:16 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
Yuma Prvg Ground, AZ (K1Y7), launched 00:00Z, 0.2 hours before the alert went out and 130 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
- 761 J/kg
- Mixed-layer CIN
- -65 J/kg
- Mixed-layer LCL
- 2897 m above ground
- 0-6 km bulk shear
- 12 kt
- 0-1 km storm-relative helicity
- 34 m²/s²
- 0-3 km storm-relative helicity
- 51 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
036
WGUS55 KPSR 310014
FFWPSR
CAC025-065-310415-
/O.NEW.KPSR.FF.W.0230.210831T0014Z-210831T0415Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Phoenix AZ
514 PM PDT Mon Aug 30 2021
The National Weather Service in Phoenix has issued a
* Flash Flood Warning for...
Northeastern Imperial County in southeastern California...
Riverside County in southern California...
* Until 915 PM PDT.
* At 514 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.
IMPACT...Life threatening flash flooding of creeks and streams,
urban areas, highways, streets and underpasses.
* Some locations that will experience flash flooding include...
Desert Center, Blythe, Midland, Nicholls Warm Springs, Blythe
Airport, Ripley and Palo Verde.
This includes the following highways...
CA Route 177 near mile marker 1...and
between mile markers 10 and 18.
CA Route 78 between mile markers 68 and 77.
CA Interstate 10 between mile markers 104 and 113.
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 3349 11515 3371 11542 3408 11529 3408 11475
3359 11462 3341 11473 3336 11471 3329 11474
3327 11481
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
INS3 follow-up statements
806
WGUS75 KPSR 310115
FFSPSR
Flash Flood Statement
National Weather Service Phoenix AZ
615 PM PDT Mon Aug 30 2021
CAC025-065-310415-
/O.CON.KPSR.FF.W.0230.000000T0000Z-210831T0415Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Imperial CA-Riverside CA-
615 PM PDT Mon Aug 30 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 915 PM PDT THIS
EVENING FOR NORTHEASTERN IMPERIAL AND RIVERSIDE COUNTIES...
At 615 PM PDT, Doppler radar indicated thunderstorms producing heavy
rain across the warned area. Up to 2 inches of rain have fallen.
Additional rainfall amounts up to 0.5 inches are possible in the
warned area. Flash flooding is ongoing or expected to begin shortly.
HAZARD...Life threatening flash flooding. Thunderstorms producing
flash flooding.
SOURCE...Radar.
IMPACT...Life threatening flash flooding of creeks and streams,
urban areas, highways, streets and underpasses.
Some locations that will experience flash flooding include...
Desert Center, Blythe, Midland, Nicholls Warm Springs, Blythe
Airport, Ripley and Palo Verde.
This includes the following highways...
CA Route 177 near mile marker 1...and
between mile markers 10 and 18.
CA Route 78 between mile markers 68 and 77.
CA Interstate 10 between mile markers 104 and 113.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Be aware of your surroundings and do not drive on flooded roads.
&&
LAT...LON 3349 11515 3371 11542 3408 11529 3408 11475
3359 11462 3341 11473 3336 11471 3329 11474
3327 11481
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
INS697
WGUS75 KPSR 310243
FFSPSR
Flash Flood Statement
National Weather Service Phoenix AZ
743 PM PDT Mon Aug 30 2021
CAC025-065-310415-
/O.CON.KPSR.FF.W.0230.000000T0000Z-210831T0415Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Imperial CA-Riverside CA-
743 PM PDT Mon Aug 30 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 915 PM PDT THIS
EVENING FOR NORTHEASTERN IMPERIAL AND RIVERSIDE COUNTIES...
At 743 PM PDT, Doppler radar indicated thunderstorms producing heavy
rain across the warned area. Up to 2 inches of rain have fallen.
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...
Desert Center, Blythe, Midland, Nicholls Warm Springs, Blythe
Airport, Ripley and Palo Verde.
This includes the following highways...
CA Route 177 near mile marker 1...and
between mile markers 10 and 18.
CA Route 78 between mile markers 68 and 77.
CA Interstate 10 between mile markers 104 and 113.
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 3349 11515 3371 11542 3408 11529 3408 11475
3359 11462 3341 11473 3336 11471 3329 11474
3327 11481
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
INS771
WGUS75 KPSR 310413
FFSPSR
Flash Flood Statement
National Weather Service Phoenix AZ
913 PM PDT Mon Aug 30 2021
CAC025-065-310423-
/O.EXP.KPSR.FF.W.0230.000000T0000Z-210831T0415Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Imperial CA-Riverside CA-
913 PM PDT Mon Aug 30 2021
...FLASH FLOOD WARNING WILL EXPIRE AT 915 PM PDT THIS EVENING FOR
NORTHEASTERN IMPERIAL AND RIVERSIDE COUNTIES...
Flood waters have receded. The heavy rain has ended. Flooding is no
longer expected to pose a threat. Please continue to heed remaining
road closures.
LAT...LON 3349 11515 3371 11542 3408 11529 3408 11475
3359 11462 3341 11473 3336 11471 3329 11474
3327 11481
$$
18The office that day
Everything else NWS Phoenix, AZ issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 30, 6:49 PM PDT | Areal Flood Advisory | PSR | Imperial | 3 hr |
| Aug 30, 7:37 PM PDT | Special Weather Statement | PSR | Riverside | 23 min |
| Aug 30, 7:52 PM PDT | Areal Flood Advisory | PSR | Riverside | 23 min |
| Aug 30, 8:13 PM PDT | Flash Flood Warning | PSR | Riverside | 50 min |
| Aug 30, 9:06 PM PDT | Flash Flood Warning | PSR | Riverside | 5 hr |
| Aug 31, 5:46 AM PDT | Areal Flood Advisory | PSR | Imperial | 3 hr |
| Aug 31, 1:13 PM PDT | Areal Flood Advisory | PSR | Imperial, Riverside | 6 hr |
| Aug 31, 1:24 PM PDT | Flash Flood Warning | PSR | Imperial, Riverside | 13 hr |
| Aug 31, 3:48 PM PDT | Special Weather Statement | PSR | Imperial | 87 min |
| Aug 31, 4:15 PM PDT | Special Weather Statement | PSR | Imperial | 90 min |
| Aug 31, 4:30 PM PDT | Severe Thunderstorm Warning | PSR | Imperial | 75 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.