Alert archive / California / Flash Flood Watches in 2021
Flash Flood Watch 9, NWS Phoenix, AZ
NWS Phoenix, AZ issued this flash flood watch at Sep 24, 2021, 9:03 AM PDT for Imperial County, Riverside County, San Bernardino County, California. It was in force for 10 hr.
The area
The counties it named.
The facts
- Issued
- Sep 24, 2021, 9:03 AM PDT (16:03 UTC)
- Expired
- Sep 24, 2021, 7:00 PM PDT
- In force
- 10 hr
- Issued by
- NWS Phoenix, AZ
- Flood severity
- None
Counties Imperial County, CA, Riverside County, CA, San Bernardino County, CA
The radar
The San Diego radar (KNKX), 154 km from the middle of the area, began a volume at 16:06 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, 4.1 hours before the alert went out and 174 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.
764 WGUS65 KPSR 241603 FFAPSR URGENT - IMMEDIATE BROADCAST REQUESTED Flood Watch National Weather Service Phoenix AZ 903 AM PDT Fri Sep 24 2021 CAZ560>570-250015- /O.NEW.KPSR.FF.A.0009.210924T1603Z-210925T0200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Joshua Tree NP West-Joshua Tree NP East-Imperial County Southwest- Salton Sea-Chuckwalla Mountains-Imperial County Southeast-Imperial County West-Imperial Valley-Chiriaco Summit-Palo Verde Valley- Chuckwalla Valley- Including the cities of Midland, Salton City, Brawley, Lost Horse-Keys Village, Palo Verde, Mountain Spring, Coolidge Springs, Winona, Chiriaco Summit, Calexico, Blythe, Plaster City, Coyote Wells, Ripley, Cottonwood Visitor, Martinez Lake, Desert Shores, Ocotillo, Alamorio, Imperial Hot Mineral Springs, Winterhaven, and El Centro 903 AM PDT Fri Sep 24 2021 ...FLASH FLOOD WATCH IN EFFECT UNTIL 7 PM PDT THIS EVENING... The National Weather Service in Phoenix has issued a * Flash Flood Watch for portions of southeast California and southern California, including the following areas, in southeast California, Chuckwalla Mountains, Chuckwalla Valley, Imperial County Southeast, Imperial County Southwest, Imperial County West, Imperial Valley, Palo Verde Valley and Salton Sea. In southern California, Chiriaco Summit, Joshua Tree NP East and Joshua Tree NP West. * Until 7 PM PDT this evening. * Conditions are exceptionally humid across portions of southeastern California. A low pressure system will tap into this moisture, creating a favorable environment for flash flooding through this evening. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued. && $$ Hirsch
2 follow-up statements
204 WGUS65 KPSR 241953 FFAPSR Flood Watch National Weather Service Phoenix AZ 1253 PM PDT Fri Sep 24 2021 CAZ560>570-250200- /O.CON.KPSR.FF.A.0009.000000T0000Z-210925T0200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Joshua Tree NP West-Joshua Tree NP East-Imperial County Southwest- Salton Sea-Chuckwalla Mountains-Imperial County Southeast-Imperial County West-Imperial Valley-Chiriaco Summit-Palo Verde Valley- Chuckwalla Valley- Including the cities of Midland, Salton City, Brawley, Lost Horse-Keys Village, Palo Verde, Mountain Spring, Coolidge Springs, Winona, Chiriaco Summit, Calexico, Blythe, Plaster City, Coyote Wells, Ripley, Cottonwood Visitor, Martinez Lake, Desert Shores, Ocotillo, Alamorio, Imperial Hot Mineral Springs, Winterhaven, and El Centro 1253 PM PDT Fri Sep 24 2021 ...FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL 7 PM PDT THIS EVENING... The Flash Flood Watch continues for * Portions of southeast California and southern California, including the following areas, in southeast California, Chuckwalla Mountains, Chuckwalla Valley, Imperial County Southeast, Imperial County Southwest, Imperial County West, Imperial Valley, Palo Verde Valley and Salton Sea. In southern California, Chiriaco Summit, Joshua Tree NP East and Joshua Tree NP West. * Until 7 PM PDT this evening. * Conditions are exceptionally humid across portions of southeastern California. A low pressure system will tap into this moisture, creating a favorable environment for flash flooding through this evening. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued. && $$ Hirsch
945 WGUS65 KPSR 250159 FFAPSR Flood Watch National Weather Service Phoenix AZ 659 PM PDT Fri Sep 24 2021 CAZ560>570-250300- /O.EXP.KPSR.FF.A.0009.000000T0000Z-210925T0200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Joshua Tree NP West-Joshua Tree NP East-Imperial County Southwest- Salton Sea-Chuckwalla Mountains-Imperial County Southeast-Imperial County West-Imperial Valley-Chiriaco Summit-Palo Verde Valley- Chuckwalla Valley- Including the cities of Midland, Salton City, Brawley, Lost Horse-Keys Village, Palo Verde, Mountain Spring, Coolidge Springs, Winona, Chiriaco Summit, Calexico, Blythe, Plaster City, Coyote Wells, Ripley, Cottonwood Visitor, Martinez Lake, Desert Shores, Ocotillo, Alamorio, Imperial Hot Mineral Springs, Winterhaven, and El Centro 659 PM PDT Fri Sep 24 2021 ...FLASH FLOOD WATCH WILL EXPIRE AT 7 PM PDT THIS EVENING... The Flash Flood Watch for portions of southeast California and southern California, including the following areas, in southeast California, Chuckwalla Mountains, Chuckwalla Valley, Imperial County Southeast, Imperial County Southwest, Imperial County West, Imperial Valley, Palo Verde Valley and Salton Sea. In southern California, Chiriaco Summit, Joshua Tree NP East and Joshua Tree NP West will expire at 7 PM PDT this evening. The Flood Watch is cancelled. Flooding is no longer expected to pose a threat. Please continue to heed remaining road closures. $$ SDB
The office that day
Everything else NWS Phoenix, AZ issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 24, 7:10 AM PDT | Special Weather Statement | PSR | Imperial | 50 min |
| Sep 24, 7:28 AM PDT | Areal Flood Advisory | PSR | Imperial | 46 min |
| Sep 24, 7:33 AM PDT | Severe Thunderstorm Warning | PSR | Imperial | 42 min |
| Sep 24, 8:00 AM PDT | Special Weather Statement | PSR | Imperial | 45 min |
| Sep 24, 8:14 AM PDT | Flash Flood Warning | PSR | Imperial | 4 hr |
| Sep 24, 8:18 AM PDT | Special Weather Statement | PSR | Imperial | 42 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.