Alert archive / California / Flash Flood Warnings in 2018
Flash Flood Warning 21, NWS San Diego, CA
NWS San Diego, CA issued this flash flood warning at Aug 16, 2018, 2:30 PM PDT for Riverside County, San Bernardino County, California. It was in force for 77 min. 2 reports 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
- Aug 16, 2018, 2:30 PM PDT (21:30 UTC)
- Expired
- Aug 16, 2018, 3:47 PM PDT
- In force
- 77 min
- Issued by
- NWS San Diego, CA
- Area
- Storm-based polygon
- Flood severity
- None
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Aug 16, 2:35 PM PDT | FLASH FLOOD | 1 Se Cherry Valley, CA | CHP REPORTS BROOKSIDE AVE AND HIGHLAND SPRINGS AVE FLOODED OUT ON BOTH SIDES OF THE ROAD. |
| Aug 16, 2:37 PM PDT | FLOOD | 1 Se Cherry Valley, CA | CHP REPORTS ROAD FLOODED ON BOTH SIDES AT INTERSECTION OF BROOKSIDE AVE /HIGHLAND SPRINGS AVE IN BEAUMONT. |
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, 9.5 hours before the alert went out and 137 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
- 810 m above ground
- 0-6 km bulk shear
- 11 kt
- 0-1 km storm-relative helicity
- -17 m²/s²
- 0-3 km storm-relative helicity
- -3 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
249 WGUS56 KSGX 162130 FFWSGX CAC065-071-170030- /O.NEW.KSGX.FF.W.0021.180816T2130Z-180817T0030Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ BULLETIN - EAS ACTIVATION REQUESTED Flash Flood Warning National Weather Service San Diego CA 230 PM PDT THU AUG 16 2018 The National Weather Service in San Diego has issued a * Flash Flood Warning for... San Bernardino County in southern California... Riverside County in southern California... * Until 530 PM PDT * At 223 PM PDT, Doppler radar indicated thunderstorms producing heavy rain across the warned area. Flash flooding will likely begin shortly. Excessive rainfall over the valley fire burn scar likely result in debris flow moving through the valley of the falls and mill creek. The debris flow can consist of rock, mud, vegetation and other loose materials. * Some locations that will likely experience flooding include... Yucaipa, Forest Falls, Highways 243 and 38, Badlands, Mentone, Interstate 10, Beaumont, Banning, Cali Mesa, Ramona Expressway, and Lambs Canyon. PRECAUTIONARY/PREPAREDNESS ACTIONS... Turn around, don't drown when encountering flooded roads. Most flood deaths occur in vehicles. && LAT...LON 3418 11662 3376 11678 3375 11713 3412 11710 $$ JMB
2 follow-up statements
555 WGUS76 KSGX 162218 FFSSGX Flash Flood Statement National Weather Service San Diego CA 318 PM PDT THU AUG 16 2018 CAC065-071-170030- /O.CON.KSGX.FF.W.0021.000000T0000Z-180817T0030Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ San Bernardino CA-Riverside CA- 318 PM PDT THU AUG 16 2018 ...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 530 PM PDT FOR SAN BERNARDINO AND RIVERSIDE COUNTIES... At 314 PM PDT, Doppler radar indicated the thunderstorms had mostly weakened in the warning area from Beaumont to north of Hemet. However, flooding had already occurred in the Cherry Valley Area at 237 PM. Low-lying locations between Beaumont and San Jacinto could have standing water through 430 PM. Any additional thunderstorms that develop will likely have heavy rain and could cause flash flooding. Some locations that could experience flooding include... Moreno Valley, Redlands, Yucaipa, Mount San Gorgonio, Forest Falls, Hwy 243 Between Banning And Idyllwild, Hemet, Highland, San Jacinto, Beaumont, Banning, Cabazon, Mountain Home Village, Mentone, Valle Vista, Angelus Oaks, Hwy 38 Between Yucaipa And Onyx Summit, Whitewater, Calimesa and Saboba Indian Reservation. PRECAUTIONARY/PREPAREDNESS ACTIONS... Turn around, don't drown when encountering flooded roads. Most flood deaths occur in vehicles. && LAT...LON 3418 11662 3376 11678 3375 11713 3412 11710 $$ Maxwell
637 WGUS76 KSGX 162247 FFSSGX Flash Flood Statement National Weather Service San Diego CA 347 PM PDT THU AUG 16 2018 CAC065-071-162256- /O.CAN.KSGX.FF.W.0021.000000T0000Z-180817T0030Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ San Bernardino CA-Riverside CA- 347 PM PDT THU AUG 16 2018 ...THE FLASH FLOOD WARNING FOR SAN BERNARDINO AND RIVERSIDE COUNTIES IS CANCELLED... The heavy rain has ended. Flooding is no longer expected to pose a threat. Please continue to heed any remaining road closures. LAT...LON 3418 11662 3376 11678 3375 11713 3412 11710 $$ MGM
The office that day
Everything else NWS San Diego, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 15, 7:25 PM PDT | Flash Flood Watch | SGX | Riverside, San Bernardino, San Diego | 25 hr |
| Aug 16, 12:45 PM PDT | Flash Flood Warning | SGX | Riverside | 3 hr |
| Aug 16, 1:20 PM PDT | Areal Flood Advisory | SGX | San Bernardino | 3 hr |
| Aug 16, 1:37 PM PDT | Flash Flood Warning | SGX | San Bernardino | 3 hr |
| Aug 16, 1:58 PM PDT | Severe Thunderstorm Warning | SGX | Riverside | 62 min |
| Aug 16, 2:34 PM PDT | Severe Thunderstorm Warning | SGX | Riverside | 56 min |
| Aug 16, 3:04 PM PDT | Flash Flood Warning | SGX | San Bernardino | 68 min |
| Aug 16, 3:09 PM PDT | Severe Thunderstorm Warning | SGX | San Bernardino | 53 min |
Nearby
Flash Flood Warnings in California, 2018Every flash flood warning in 2018
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.