Alert archive / California / Flash Flood Watches in 2021
Flash Flood Watch 7, NWS San Diego, CA
NWS San Diego, CA issued this flash flood watch at Aug 30, 2021, 2:38 AM PDT for Riverside County, San Bernardino County, San Diego County, California. It took effect at Aug 31, 2021, 11:00 AM PDT. It was in force for 10 hr.
The area
The counties it named.
The facts
- Issued
- Aug 30, 2021, 2:38 AM PDT (09:38 UTC)
- In effect from
- Aug 31, 2021, 11:00 AM PDT
- Expired
- Aug 31, 2021, 9:00 PM PDT
- In force
- 10 hr
- Issued by
- NWS San Diego, CA
- Flood severity
- None
Counties Riverside County, CA, San Bernardino County, CA, San Diego County, CA
The radar
The Santa Ana Mts radar (KSOX), 122 km from the middle of the area, began a volume at 09:41 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 00:00Z, 9.6 hours before the alert went out and 145 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
- 1 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 3108 m above ground
- 0-6 km bulk shear
- 29 kt
- 0-1 km storm-relative helicity
- 20 m²/s²
- 0-3 km storm-relative helicity
- 110 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
676 WGUS66 KSGX 300938 FFASGX URGENT - IMMEDIATE BROADCAST REQUESTED Flood Watch National Weather Service San Diego CA 238 AM PDT Mon Aug 30 2021 CAZ055-056-058-060>062-065-302315- /O.NEW.KSGX.FF.A.0007.210831T1800Z-210901T0500Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ San Bernardino County Mountains-Riverside County Mountains-San Diego County Mountains-Apple and Lucerne Valleys-Coachella Valley-San Diego County Deserts-San Gorgonio Pass Near Banning- Including the cities of Palm Springs, La Quinta, Idyllwild-Pine Cove, Lucerne Valley, Apple Valley, Banning, Hesperia, Borrego Springs, Big Bear Lake, Big Bear City, Palm Desert Country, Coachella, Cathedral City, Palm Desert, Crestline, Indio, Victorville, Wrightwood, Julian, Pine Valley, Lake Arrowhead, Running Springs, and Desert Hot Springs 238 AM PDT Mon Aug 30 2021 ...FLASH FLOOD WATCH IN EFFECT FROM LATE TUESDAY MORNING THROUGH TUESDAY EVENING... The National Weather Service in San Diego has issued a * Flash Flood Watch for a portion of southwest California, including the following areas, Apple and Lucerne Valleys, Coachella Valley, Riverside County Mountains, San Bernardino County Mountains, San Diego County Deserts, San Diego County Mountains and San Gorgonio Pass Near Banning. * From Tuesday morning through Tuesday evening. * Thunderstorms may develop in the mountains and move into the deserts with rainfall rates of 1 to 2 inches per hour possible. This would cause rapid runoff with flash flooding possible. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued. && $$ 17
5 follow-up statements
937 WGUS66 KSGX 302017 FFASGX Flood Watch National Weather Service San Diego CA 117 PM PDT Mon Aug 30 2021 CAZ055-056-058-060>062-065-310430- /O.CON.KSGX.FF.A.0007.210831T1800Z-210901T0500Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ San Bernardino County Mountains-Riverside County Mountains-San Diego County Mountains-Apple and Lucerne Valleys-Coachella Valley-San Diego County Deserts-San Gorgonio Pass Near Banning- Including the cities of Palm Springs, La Quinta, Idyllwild-Pine Cove, Lucerne Valley, Apple Valley, Banning, Hesperia, Borrego Springs, Big Bear Lake, Big Bear City, Palm Desert Country, Coachella, Cathedral City, Palm Desert, Crestline, Indio, Victorville, Wrightwood, Julian, Pine Valley, Lake Arrowhead, Running Springs, and Desert Hot Springs 117 PM PDT Mon Aug 30 2021 ...FLASH FLOOD WATCH REMAINS IN EFFECT FROM TUESDAY MORNING THROUGH TUESDAY EVENING... The Flash Flood Watch continues for * A portion of southwest California, including the following areas, Apple and Lucerne Valleys, Coachella Valley, Riverside County Mountains, San Bernardino County Mountains, San Diego County Deserts, San Diego County Mountains and San Gorgonio Pass Near Banning. * From Tuesday morning through Tuesday evening. * Thunderstorms may develop in the mountains and move into the deserts with rainfall rates of 1 to 2 inches per hour possible. This would cause rapid runoff with flash flooding possible. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued. && $$ Gregoria
507 WGUS66 KSGX 310438 FFASGX Flood Watch National Weather Service San Diego CA 938 PM PDT Mon Aug 30 2021 CAZ055-056-058-060>062-065-311245- /O.CON.KSGX.FF.A.0007.210831T1800Z-210901T0500Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ San Bernardino County Mountains-Riverside County Mountains-San Diego County Mountains-Apple and Lucerne Valleys-Coachella Valley-San Diego County Deserts-San Gorgonio Pass Near Banning- Including the cities of Palm Springs, La Quinta, Idyllwild-Pine Cove, Lucerne Valley, Apple Valley, Banning, Hesperia, Borrego Springs, Big Bear Lake, Big Bear City, Palm Desert Country, Coachella, Cathedral City, Palm Desert, Crestline, Indio, Victorville, Wrightwood, Julian, Pine Valley, Lake Arrowhead, Running Springs, and Desert Hot Springs 938 PM PDT Mon Aug 30 2021 ...FLASH FLOOD WATCH REMAINS IN EFFECT FROM TUESDAY MORNING THROUGH TUESDAY EVENING... The Flash Flood Watch continues for * A portion of southwest California, including the following areas, Apple and Lucerne Valleys, Coachella Valley, Riverside County Mountains, San Bernardino County Mountains, San Diego County Deserts, San Diego County Mountains and San Gorgonio Pass Near Banning. * From Tuesday morning through Tuesday evening. * Thunderstorms may develop in the mountains and move into the deserts with rainfall rates of 1 to 2 inches per hour possible. This would cause rapid runoff with flash flooding possible. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued. && $$ 10
522 WGUS66 KSGX 311103 FFASGX Flood Watch National Weather Service San Diego CA 403 AM PDT Tue Aug 31 2021 CAZ055-056-058-060>062-065-312315- /O.CON.KSGX.FF.A.0007.210831T1800Z-210901T0500Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ San Bernardino County Mountains-Riverside County Mountains-San Diego County Mountains-Apple and Lucerne Valleys-Coachella Valley-San Diego County Deserts-San Gorgonio Pass Near Banning- Including the cities of Palm Springs, La Quinta, Idyllwild-Pine Cove, Lucerne Valley, Apple Valley, Banning, Hesperia, Borrego Springs, Big Bear Lake, Big Bear City, Palm Desert Country, Coachella, Cathedral City, Palm Desert, Crestline, Indio, Victorville, Wrightwood, Julian, Pine Valley, Lake Arrowhead, Running Springs, and Desert Hot Springs 403 AM PDT Tue Aug 31 2021 ...FLASH FLOOD WATCH REMAINS IN EFFECT FROM 11 AM PDT THIS MORNING THROUGH THIS EVENING... The Flash Flood Watch continues for * A portion of southwest California, including the following areas, Apple and Lucerne Valleys, Coachella Valley, Riverside County Mountains, San Bernardino County Mountains, San Diego County Deserts, San Diego County Mountains and San Gorgonio Pass Near Banning. * From 11 AM PDT this morning through this evening. * A few thunderstorms may develop in the mountains this afternoon and move into the deserts during the late afternoon and early evening as the sea breeze moves inland. Isolated strong thunderstorms could generate rainfall rates of 1 to 2 inches per hour with flash flooding possible. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued. && $$ 17
988 WGUS66 KSGX 311935 FFASGX Flood Watch National Weather Service San Diego CA 1235 PM PDT Tue Aug 31 2021 CAZ055-056-058-060>062-065-010345- /O.CON.KSGX.FF.A.0007.000000T0000Z-210901T0500Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ San Bernardino County Mountains-Riverside County Mountains-San Diego County Mountains-Apple and Lucerne Valleys-Coachella Valley-San Diego County Deserts-San Gorgonio Pass Near Banning- Including the cities of Palm Springs, La Quinta, Idyllwild-Pine Cove, Lucerne Valley, Apple Valley, Banning, Hesperia, Borrego Springs, Big Bear Lake, Big Bear City, Palm Desert Country, Coachella, Cathedral City, Palm Desert, Crestline, Indio, Victorville, Wrightwood, Julian, Pine Valley, Lake Arrowhead, Running Springs, and Desert Hot Springs 1235 PM PDT Tue Aug 31 2021 ...FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL 10 PM PDT THIS EVENING... The Flash Flood Watch continues for * A portion of southwest California, including the following areas, Apple and Lucerne Valleys, Coachella Valley, Riverside County Mountains, San Bernardino County Mountains, San Diego County Deserts, San Diego County Mountains and San Gorgonio Pass Near Banning. * Until 10 PM PDT this evening. * A few thunderstorms will develop in the mountains this afternoon and move into the deserts during the late afternoon and early evening as the sea breeze moves inland. Isolated strong thunderstorms could generate rainfall rates of 1 to 2 inches per hour with flash flooding possible. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued. && $$ Schenk/Oswant
483 WGUS66 KSGX 010400 FFASGX Flood Watch National Weather Service San Diego CA 900 PM PDT Tue Aug 31 2021 CAZ055-056-058-060>062-065-010500- /O.CAN.KSGX.FF.A.0007.000000T0000Z-210901T0500Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ San Bernardino County Mountains-Riverside County Mountains-San Diego County Mountains-Apple and Lucerne Valleys-Coachella Valley-San Diego County Deserts-San Gorgonio Pass Near Banning- Including the cities of Palm Springs, La Quinta, Idyllwild-Pine Cove, Lucerne Valley, Apple Valley, Banning, Hesperia, Borrego Springs, Big Bear Lake, Big Bear City, Palm Desert Country, Coachella, Cathedral City, Palm Desert, Crestline, Indio, Victorville, Wrightwood, Julian, Pine Valley, Lake Arrowhead, Running Springs, and Desert Hot Springs 900 PM PDT Tue Aug 31 2021 ...FLASH FLOOD WATCH IS CANCELLED... The Flash Flood Watch for a portion of southwest California, including the following areas, Apple and Lucerne Valleys, Coachella Valley, Riverside County Mountains, San Bernardino County Mountains, San Diego County Deserts, San Diego County Mountains and San Gorgonio Pass Near Banning has been cancelled. The Flood Watch is cancelled. Flooding is no longer expected to pose a threat. Please continue to heed any road closures. $$ 10
The office that day
Everything else NWS San Diego, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 30, 11:30 AM PDT | Areal Flood Advisory | SGX | San Bernardino | 3 hr |
| Aug 30, 12:22 PM PDT | Areal Flood Advisory | SGX | San Diego | 113 min |
| Aug 30, 12:39 PM PDT | Special Weather Statement | SGX | San Diego | 51 min |
| Aug 30, 1:17 PM PDT | Areal Flood Advisory | SGX | Riverside, San Diego | 118 min |
| Aug 30, 2:22 PM PDT | Areal Flood Advisory | SGX | Riverside | 113 min |
Nearby
Flash Flood Watches in California, 2021Every flash flood watch 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.