Alert archive / California / Flash Flood Warnings in 2021
Flash Flood Warning 18, NWS San Diego, CA
NWS San Diego, CA issued this flash flood warning at Sep 24, 2021, 1:28 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 24, 2021, 1:28 PM PDT (20:28 UTC)
- Expired
- Sep 24, 2021, 3:30 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), 46 km from the middle of the area, began a volume at 20:31 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 24, 2:00 PM PDT | HEAVY RAIN 1.46 | 8 Nw Santa Ysabel, CA | MESONET STATION MEGC1 8.2 NW SANTA YSABEL (CNRFC). |
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, 8.5 hours before the alert went out and 64 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
- 1990 m above ground
- 0-6 km bulk shear
- 4 kt
- 0-1 km storm-relative helicity
- -36 m²/s²
- 0-3 km storm-relative helicity
- 15 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
751
WGUS56 KSGX 242028
FFWSGX
CAC073-242230-
/O.NEW.KSGX.FF.W.0018.210924T2028Z-210924T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service San Diego CA
128 PM PDT Fri Sep 24 2021
The National Weather Service in San Diego has issued a
* Flash Flood Warning for...
North Central San Diego County in southwestern California...
* Until 330 PM PDT.
* At 128 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...
Valley Center, Palomar Mountain, Lake Henshaw, Hwy 79 Between
Warner Springs And Oak Grove, Hwy 79 Between Oak Grove And
Aguanga, Hwy 79 Between Santa Ysabel And Warner Springs, Warner
Springs, Hwy S2 Between Hwy 79 And Hwy 78, La Jolla Indian
Reservation, Rincon Indian Reservation, Oak Grove, Pauma Valley,
San Pasqual Indian Reservation, Pauma Indian Reservation, Santa
Ysabel Indian Reservation.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 3342 11702 3342 11679 3314 11656 3316 11702
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
Maxwell2 follow-up statements
317
WGUS76 KSGX 242158
FFSSGX
Flash Flood Statement
National Weather Service San Diego CA
258 PM PDT Fri Sep 24 2021
CAC073-242230-
/O.CON.KSGX.FF.W.0018.000000T0000Z-210924T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Diego CA-
258 PM PDT Fri Sep 24 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 330 PM PDT THIS
AFTERNOON FOR NORTH CENTRAL SAN DIEGO COUNTY...
At 258 PM PDT, Doppler radar indicated thunderstorms producing heavy
rain continuing across the warned area. Flash flooding will be
likely in and near heavy rain. Radar estimated local rainfall
amounts over 3 inches this afternoon.
HAZARD...Life threatening flash flooding. Thunderstorms producing
flash flooding.
SOURCE...Radar.
IMPACT...Life threatening flash flooding of creeks and streams,
urban areas, highways, streets and underpasses.
Some locations that will experience flash flooding include...
Valley Center, Palomar Mountain, Lake Henshaw, Hwy 79 Between
Warner Springs And Oak Grove, Hwy 79 Between Oak Grove And
Aguanga, Hwy 79 Between Santa Ysabel And Warner Springs, Warner
Springs, Hwy S2 Between Hwy 79 And Hwy 78, La Jolla Indian
Reservation, Rincon Indian Reservation, Oak Grove, Pauma Valley,
San Pasqual Indian Reservation, Pauma Indian Reservation, Santa
Ysabel Indian Reservation.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 3342 11702 3342 11679 3314 11656 3316 11702
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
Maxwell205 WGUS76 KSGX 242228 FFSSGX Flash Flood Statement National Weather Service San Diego CA 328 PM PDT Fri Sep 24 2021 CAC073-242238- /O.EXP.KSGX.FF.W.0018.000000T0000Z-210924T2230Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ San Diego CA- 328 PM PDT Fri Sep 24 2021 ...FLASH FLOOD WARNING WILL EXPIRE AT 330 PM PDT THIS AFTERNOON FOR NORTH CENTRAL SAN DIEGO COUNTY... While a few thunderstorms will continue after 330 PM, new flooding is not likely. Please be careful when driving near any previously flooded areas. A Flash Flood Watch remains in effect until 700 PM PDT for a portion of southwest California. LAT...LON 3342 11702 3342 11679 3314 11656 3316 11702 $$ Maxwell
The office that day
Everything else NWS San Diego, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 24, 8:56 AM PDT | Flash Flood Watch | SGX | Riverside, San Diego | 10 hr |
| Sep 24, 11:08 AM PDT | Beach Hazards Statement | SGX | Orange, San Diego | 8 hr |
| Sep 24, 12:13 PM PDT | Severe Thunderstorm Warning | SGX | San Diego | 31 min |
| Sep 24, 12:21 PM PDT | Flash Flood Warning | SGX | San Diego | 56 min |
| Sep 24, 1:24 PM PDT | Severe Thunderstorm Warning | SGX | San Diego | 51 min |
| Sep 24, 2:09 PM PDT | Flash Flood Warning | SGX | San Diego | 3 hr |
| Sep 24, 2:41 PM PDT | Severe Thunderstorm Warning | SGX | San Diego | 64 min |
| Sep 24, 2:59 PM PDT | Special Weather Statement | SGX | San Diego | 61 min |
| Sep 24, 3:14 PM PDT | Special Marine Warning | SGX | 91 min | |
| Sep 24, 3:20 PM PDT | Severe Thunderstorm Warning | SGX | San Diego | 55 min |
| Sep 24, 3:47 PM PDT | Special Weather Statement | SGX | Orange | 58 min |
| Sep 24, 3:56 PM PDT | Special Marine Warning | SGX | 94 min | |
| Sep 24, 4:40 PM PDT | Special Marine Warning | SGX | 65 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.