Alert archive / California / Flash Flood Warnings in 2021
Flash Flood Warning 2, NWS San Diego, CA
NWS San Diego, CA issued this flash flood warning at Jul 22, 2021, 3:45 PM PDT for San Diego 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, 3:45 PM PDT (22:45 UTC)
- Expired
- Jul 22, 2021, 5:45 PM PDT
- In force
- 2 hr
- Issued by
- NWS San Diego, CA
- Area
- Storm-based polygon
- Damage threat
- Considerable
- Flood severity
- None
County San Diego County, CA
The radar
The San Diego radar (KNKX), 84 km from the middle of the area, began a volume at 22:48 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, 10.8 hours before the alert went out and 96 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.
923
WGUS56 KSGX 222245
FFWSGX
CAC073-230045-
/O.NEW.KSGX.FF.W.0002.210722T2245Z-210723T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service San Diego CA
345 PM PDT Thu Jul 22 2021
The National Weather Service in San Diego has issued a
* Flash Flood Warning for...
Southeastern San Diego County in southwestern California...
* Until 545 PM PDT.
* At 345 PM PDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. The expected rainfall rate is
0.5 to 1 inch in 1 hour. 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...
I-8 Between Boulevard And Imperial County Line, northeastern
Boulevard, Hwy S2 Between Canebrake And Imperial County Line and
Jacumba.
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.
&&
LAT...LON 3261 11622 3276 11627 3280 11610 3262 11611
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
EXPECTED RAINFALL...0.5-1 INCH IN 1 HOUR
$$
SS2 follow-up statements
273
WGUS76 KSGX 222327
FFSSGX
Flash Flood Statement
National Weather Service San Diego CA
427 PM PDT Thu Jul 22 2021
CAC073-230045-
/O.CON.KSGX.FF.W.0002.000000T0000Z-210723T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Diego CA-
427 PM PDT Thu Jul 22 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 545 PM PDT THIS
AFTERNOON FOR SOUTHEASTERN SAN DIEGO COUNTY...
At 427 PM PDT, Doppler radar indicated thunderstorms producing heavy
rain across the warned area. The expected rainfall rate is 0.25
inches in 1 hour. Flash flooding is ongoing or expected to begin
shortly.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Radar.
IMPACT...Flash flooding of small creeks and streams, urban areas,
highways, streets and underpasses as well as other poor
drainage and low-lying areas.
Some locations that will experience flash flooding include...
I-8 Between Boulevard And Imperial County Line, northeastern
Boulevard, Hwy S2 Between Canebrake And Imperial County Line and
Jacumba.
Storms have weakened and moved out of the warned area, however,
residual runoff may pose a threat, including along I-8.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.
&&
LAT...LON 3261 11622 3276 11627 3280 11610 3262 11611
FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...0.25 INCHES IN 1 HOUR
$$
SS822 WGUS76 KSGX 230036 FFSSGX Flash Flood Statement National Weather Service San Diego CA 536 PM PDT Thu Jul 22 2021 CAC073-230046- /O.EXP.KSGX.FF.W.0002.000000T0000Z-210723T0045Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ San Diego CA- 536 PM PDT Thu Jul 22 2021 ...FLASH FLOOD WARNING WILL EXPIRE AT 545 PM PDT THIS AFTERNOON FOR SOUTHEASTERN SAN DIEGO COUNTY... The heavy rain has ended. Flooding is no longer expected to pose a threat. Please continue to heed remaining road closures. LAT...LON 3261 11622 3276 11627 3280 11610 3262 11611 $$ SS
The office that day
Everything else NWS San Diego, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| 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 |
| Jul 22, 4:23 PM PDT | Flash Flood Warning | SGX | Riverside | 2 hr |
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.