Alert archive / California / Flash Flood Warnings in 2022

Flash Flood Warning 21, NWS San Diego, CA

August 12, 2022Riverside County, California

NWS San Diego, CA issued this flash flood warning at Aug 12, 2022, 11:43 PM PDT for Riverside County, California. It was in force for 3 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
Aug 12, 2022, 11:43 PM PDT (06:43 UTC)
Expired
Aug 13, 2022, 2:45 AM PDT
In force
3 hr
Issued by
NWS San Diego, CA
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

County Riverside County, CA

The radar

The San Diego radar (KNKX), 115 km from the middle of the area, began a volume at 06:42 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

TimeReportWhereRemark
Aug 13, 2:00 AM PDTHEAVY RAIN 0.913 Sw Mecca, CAKENT SEA FARMS NEAR MECCA RECORDED 0.91 INCHES OF RAINFALL OVERNIGHT FROM AN MCS THAT MOVED SOUTHWARD FROM JOSHUA TREE INTO THE LOWER DESERTS. MRMS QPE SHOWED MUCH HEAVIER RAIN FELL OVER AREAS BETWEEN MECCA AND INTERSTATE 10 WITH BASIN AVERAGE OF 1.5-2.5 INCHE

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 00:00Z, 6.7 hours before the alert went out and 135 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.

Skew-T log-pSkew-T log-p diagram, San Diego, CA at 00:00Z on 2022-08-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, San Diego, CA at 00:00Z on 2022-08-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 20 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3647 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
20 m²/s²
0-3 km storm-relative helicity
27 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

814 
WGUS56 KSGX 130643
FFWSGX
CAC065-130945-
/O.NEW.KSGX.FF.W.0021.220813T0643Z-220813T0945Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service San Diego CA
1143 PM PDT Fri Aug 12 2022

The National Weather Service in San Diego has issued a

* Flash Flood Warning for...
  Riverside County in southern California...

* Until 245 AM PDT.

* At 1143 PM PDT, Doppler radar indicated thunderstorms producing 
  heavy rain east of Indio along Interstate 10 to Mecca. Between 1 
  and 1.5 inches of rain have fallen. Additional rainfall amounts of 
  1 to 2 inches are possible in 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...
  Coachella, Thermal, Mecca, Interstate 10 east of Indio.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

&&

LAT...LON 3343 11603 3343 11620 3353 11626 3381 11610
      3374 11600 3374 11595 3351 11595 3352 11605
      3351 11605 3351 11607 3348 11606 3345 11604

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

Gregoria
3 follow-up statements
262 
WGUS76 KSGX 130717
FFSSGX

Flash Flood Statement
National Weather Service San Diego CA
1217 AM PDT Sat Aug 13 2022

CAC065-130945-
/O.CON.KSGX.FF.W.0021.000000T0000Z-220813T0945Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Riverside CA-
1217 AM PDT Sat Aug 13 2022

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 245 AM PDT EARLY THIS 
MORNING FOR RIVERSIDE COUNTY...

At 1217 AM PDT, Doppler radar indicated thunderstorms producing 
heavy rain over areas east and south of Indio, including along 
Interstate 10. Up to 2 inches of rain has fallen in the past hour 
just northeast of Mecca. The heaviest rain is now occurring south of 
Mecca. Additional rainfall amounts up to 1 inch is possible. Flash 
flooding is likely ongoing over the warned area.

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...
Box Canyon, Interstate 10 east of Indio, Coachella, Thermal, and 
Mecca.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

&&

LAT...LON 3343 11603 3343 11620 3353 11626 3381 11610
      3374 11600 3374 11595 3351 11595 3352 11605
      3351 11605 3351 11607 3348 11606 3345 11604

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

Gregoria
853 
WGUS76 KSGX 130906
FFSSGX

Flash Flood Statement
National Weather Service San Diego CA
206 AM PDT Sat Aug 13 2022

CAC065-130945-
/O.CON.KSGX.FF.W.0021.000000T0000Z-220813T0945Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Riverside CA-
206 AM PDT Sat Aug 13 2022

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 245 AM PDT EARLY THIS 
MORNING FOR RIVERSIDE COUNTY...

At 206 AM PDT, Doppler radar indicated that the heavy rainfall has 
subsided, but rain continues to fall over the area. Additional 
rainfall of up to a half an inch is possible. Flash flooding is 
likely ongoing from the recent heavy rainfall.

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...
Coachella, Thermal, Mecca, Interstate 10 east of Indio and Box 
Canyon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

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 3343 11603 3343 11620 3353 11626 3381 11610
      3374 11600 3374 11595 3351 11595 3352 11605
      3351 11605 3351 11607 3348 11606 3345 11604

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

Gregoria
807 
WGUS76 KSGX 130940
FFSSGX

Flash Flood Statement
National Weather Service San Diego CA
240 AM PDT Sat Aug 13 2022

CAC065-130950-
/O.EXP.KSGX.FF.W.0021.000000T0000Z-220813T0945Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Riverside CA-
240 AM PDT Sat Aug 13 2022

...FLASH FLOOD WARNING WILL EXPIRE AT 245 AM PDT EARLY THIS MORNING 
FOR RIVERSIDE COUNTY...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat. Please continue to heed remaining road closures.

A Flood Watch remains in effect until 800 PM PDT Saturday for a 
portion of Southwest California.

LAT...LON 3343 11603 3343 11620 3353 11626 3381 11610
      3374 11600 3374 11595 3351 11595 3352 11605
      3351 11605 3351 11607 3348 11606 3345 11604

$$

Gregoria

The office that day

Everything else NWS San Diego, CA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 12, 5:29 PM PDTFlash Flood Warning Considerable damage threatSGXSan Diego3 hr
Aug 12, 11:21 PM PDTSpecial Weather StatementSGXRiverside39 min
Aug 13, 12:33 AM PDTFlash Flood Warning Considerable damage threatSGXSan Diego3 hr
Aug 13, 2:32 AM PDTFlood WatchSGXRiverside, San Bernardino, San Diego16 hr
Aug 13, 12:07 PM PDTAreal Flood AdvisorySGXSan Diego118 min
Aug 13, 12:19 PM PDTSpecial Weather StatementSGXSan Diego41 min
Aug 13, 12:47 PM PDTSevere Thunderstorm WarningSGXSan Diego58 min
Aug 13, 1:01 PM PDTAreal Flood AdvisorySGXRiverside, San Bernardino117 min
Aug 13, 1:05 PM PDTSpecial Weather StatementSGXSan Diego40 min
Aug 13, 1:32 PM PDTFlash Flood Warning Considerable damage threatSGXRiverside, San Bernardino118 min
Aug 13, 2:01 PM PDTSpecial Weather StatementSGXSan Diego44 min
Aug 13, 2:21 PM PDTSevere Thunderstorm WarningSGXSan Diego54 min
Aug 13, 2:25 PM PDTAreal Flood AdvisorySGXSan Diego119 min
Aug 13, 3:05 PM PDTFlash Flood WarningSGXSan Diego3 hr
Aug 13, 3:43 PM PDTAreal Flood AdvisorySGXSan Bernardino119 min
Aug 13, 4:32 PM PDTSpecial Weather StatementSGX43 min

Nearby

Flash Flood Warnings in California, 2022Every flash flood warning in 2022

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.