Alert archive / California / Flash Flood Warnings in 2021

Flash Flood Warning 11, NWS Hanford, CA

July 30, 2021Fresno County, Madera County, Mariposa County, California

NWS Hanford, CA issued this flash flood warning at Jul 30, 2021, 3:30 PM PDT for Fresno County, Madera County, Mariposa County, California. It was in force for 60 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 30, 2021, 3:30 PM PDT (22:30 UTC)
Expired
Jul 30, 2021, 4:30 PM PDT
In force
60 min
Issued by
NWS Hanford, CA
Area
Storm-based polygon
Flood severity
None

Counties Fresno County, CA, Madera County, CA, Mariposa County, CA

The radar

The San Joaquin Valley radar (KHNX), 145 km from the middle of the area, began a volume at 22:25 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

Reno, NV (KREV), launched 12:00Z, 10.5 hours before the alert went out and 239 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, Reno, NV at 12:00Z on 2021-07-30Temperature 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, Reno, NV at 12:00Z on 2021-07-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -6 square meters per square second.19395878Sfc1 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
2579 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
-6 m²/s²
0-3 km storm-relative helicity
93 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

775 
WGUS56 KHNX 302230
FFWHNX
CAC019-039-043-302330-
/O.NEW.KHNX.FF.W.0011.210730T2230Z-210730T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service San Joaquin Valley CA
330 PM PDT Fri Jul 30 2021

The National Weather Service in Hanford CA has issued a

* Flash Flood Warning for...
  Northeastern Mariposa County in central California...
  Northeastern Madera County in central California...
  Northeastern Fresno County in central California...

* Until 430 PM PDT.

* At 326 PM PDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Two to three inches of rain 
  have already fallen. Flash flooding is ongoing or expected to 
  begin shortly.

  HAZARD...Flash flooding caused by thunderstorms in and around the 
           UPPER CREEK FIRE BURN AREA.

  SOURCE...Radar indicated.

  IMPACT...Flooding of areas in and around the UPPER CREEK FIRE BURN 
           AREA.

* Some locations that will experience flooding include...
  Clover Meadow Wilderness Office, Graveyard Meadow and Green Mtn. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move away from recently burned areas. Life-threatening flooding of 
creeks, roads and normally dry arroyos is likely. The heavy rains 
may trigger rockslides, mudslides and debris flows in steep terrain, 
especially in and around these areas.

&&

LAT...LON 3768 11912 3754 11911 3741 11922 3748 11943
      3771 11949

FLASH FLOOD...RADAR INDICATED

$$

Andersen
1 follow-up statement
634 
WGUS76 KHNX 302322
FFSHNX

Flash Flood Statement
National Weather Service San Joaquin Valley CA
422 PM PDT Fri Jul 30 2021

CAC019-039-043-302331-
/O.EXP.KHNX.FF.W.0011.000000T0000Z-210730T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mariposa CA-Madera CA-Fresno CA-
422 PM PDT Fri Jul 30 2021

...THE FLASH FLOOD WARNING FOR NORTHEASTERN MARIPOSA...NORTHEASTERN
MADERA AND NORTHEASTERN FRESNO COUNTIES WILL EXPIRE AT 430 PM PDT...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat. Any runoff will continue over the next hour. Please continue 
to heed any remaining road closures.

LAT...LON 3768 11912 3754 11911 3741 11922 3748 11943
      3771 11949

$$

Andersen

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 29, 5:20 PM PDTFlash Flood Warning Considerable damage threatHNXMadera3 hr
Jul 30, 2:52 PM PDTFlash Flood WarningHNXFresno, Madera38 min
Jul 30, 4:02 PM PDTFlash Flood WarningHNXMariposa, Tuolumne116 min
Jul 30, 4:08 PM PDTSpecial Weather StatementHNXMariposa22 min
Jul 30, 4:20 PM PDTSpecial Weather StatementHNXTuolumne40 min
Jul 30, 4:30 PM PDTSpecial Weather StatementHNXMariposa45 min
Jul 30, 4:33 PM PDTFlash Flood WarningHNXMariposa57 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.