Alert archive / California / Flash Flood Warnings in 2021
Flash Flood Warning 16, NWS San Diego, CA
NWS San Diego, CA issued this flash flood warning at Sep 10, 2021, 2:24 PM PDT for San Diego County, California. It was in force for 2 hr. 1 report 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
- Sep 10, 2021, 2:24 PM PDT (21:24 UTC)
- Expired
- Sep 10, 2021, 4:45 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), 61 km from the middle of the area, began a volume at 21:24 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 |
|---|---|---|---|
| Sep 10, 3:30 PM PDT | FLOOD | 9 Se Borrego Springs, CA | ROADWAY FLOODING. STATE HIGHWAY ROUTE 78 AND BORREGO SPRINGS ROAD. ROCKS ON ROADWAY. ROCKS ON ROADWAY. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
San Diego, CA (KNKX), launched 12:00Z, 9.4 hours before the alert went out and 79 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
- 4 J/kg
- Mixed-layer CIN
- -583 J/kg
- Mixed-layer LCL
- 1725 m above ground
- 0-6 km bulk shear
- 16 kt
- 0-1 km storm-relative helicity
- 18 m²/s²
- 0-3 km storm-relative helicity
- 40 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
768
WGUS56 KSGX 102124
FFWSGX
CAC073-102315-
/O.NEW.KSGX.FF.W.0016.210910T2124Z-210910T2315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service San Diego CA
224 PM PDT Fri Sep 10 2021
The National Weather Service in San Diego has issued a
* Flash Flood Warning for...
Eastern San Diego County in southwestern California...
* Until 415 PM PDT.
* At 224 PM PDT, Doppler radar indicated thunderstorms producing
heavy rain across 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...
Hwy 78 Between S2 And Borrego Springs Rd, Hwy 78 Between Banner
And S2, Hwy 78 Between Borrego Springs Rd And Ocotillo Wells,
Borrego Springs, Mount Laguna, I-8 Between Pine Valley And
Boulevard, Hwy S2 Between Shelter Valley And Agua Caliente, Hwy S2
Between Agua Caliente And Canebrake, Hwy S22 Between Ranchita And
Borrego Springs, Fish Creek Wash, Hwy S1 Between Lake Cuyamaca And
Mount Laguna, Ranchita, Ocotillo Wells, Hwy S2 Between Hwy 79 And
Hwy 78, Borrego Palm Canyon, Hwy S2 Vallecito Creek Rd, Hwy S2
Between Canebrake And Imperial County Line, Hwy S22 Between
Borrego Springs And Imperial County Line, northwestern Boulevard
and Shelter Valley.
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.
Remain alert for flooding even in locations not receiving rain.
Arroyos, streams, and rivers can become raging killer currents in a
matter of minutes, even from distant rainfall.
&&
LAT...LON 3334 11658 3340 11641 3332 11616 3276 11616
3267 11636 3284 11647 3304 11650 3314 11663
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
PG2 follow-up statements
820
WGUS56 KSGX 102302
FFWSGX
CAC073-102345-
/O.EXT.KSGX.FF.W.0016.000000T0000Z-210910T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service San Diego CA
402 PM PDT Fri Sep 10 2021
The National Weather Service in San Diego has extended the
* Flash Flood Warning for...
Eastern San Diego County in southwestern California...
* Until 445 PM PDT.
* At 402 PM PDT, Doppler radar indicated thunderstorms producing
heavy rain across 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...
Hwy 78 Between S2 And Borrego Springs Rd, Hwy 78 Between Banner
And S2, Hwy 78 Between Borrego Springs Rd And Ocotillo Wells,
Borrego Springs, Mount Laguna, I-8 Between Pine Valley And
Boulevard, Hwy S2 Between Shelter Valley And Agua Caliente, Hwy S2
Between Agua Caliente And Canebrake, Hwy S22 Between Ranchita And
Borrego Springs, Fish Creek Wash, Hwy S1 Between Lake Cuyamaca And
Mount Laguna, Ranchita, Ocotillo Wells, Hwy S2 Between Hwy 79 And
Hwy 78, Borrego Palm Canyon, Hwy S2 Vallecito Creek Rd, Hwy S2
Between Canebrake And Imperial County Line, Hwy S22 Between
Borrego Springs And Imperial County Line, northwestern Boulevard
and Shelter Valley.
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.
Remain alert for flooding even in locations not receiving rain.
Arroyos, streams, and rivers can become raging killer currents in a
matter of minutes, even from distant rainfall.
&&
LAT...LON 3334 11658 3340 11641 3332 11616 3276 11616
3267 11636 3284 11647 3304 11650 3314 11663
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
PG724
WGUS76 KSGX 102337
FFSSGX
Flash Flood Statement
National Weather Service San Diego CA
437 PM PDT Fri Sep 10 2021
CAC073-102347-
/O.EXP.KSGX.FF.W.0016.000000T0000Z-210910T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Diego CA-
437 PM PDT Fri Sep 10 2021
...FLASH FLOOD WARNING WILL EXPIRE AT 445 PM PDT THIS AFTERNOON FOR
EASTERN 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 3334 11658 3340 11641 3332 11616 3276 11616
3267 11636 3284 11647 3304 11650 3314 11663
$$
PGThe office that day
Everything else NWS San Diego, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 10, 1:15 PM PDT | Areal Flood Advisory | SGX | Riverside, San Diego | 3 hr |
| Sep 10, 3:06 PM PDT | Special Weather Statement | SGX | San Diego | 54 min |
| Sep 10, 3:13 PM PDT | Areal Flood Advisory | SGX | Riverside | 108 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.