Alert archive / California / Flash Flood Warnings in 2021

Flash Flood Warning 6, NWS Hanford, CA

July 29, 2021Madera County, Mariposa County, California

NWS Hanford, CA issued this flash flood warning at Jul 29, 2021, 2:03 PM PDT for Madera County, Mariposa County, California. It was in force for 117 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 29, 2021, 2:03 PM PDT (21:03 UTC)
Expired
Jul 29, 2021, 4:00 PM PDT
In force
117 min
Issued by
NWS Hanford, CA
Area
Storm-based polygon
Flood severity
None

Counties 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 21:05 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, 9.1 hours before the alert went out and 241 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 2021-07-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCLLFCEL10008507005003002001001 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 2021-07-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 16 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
2873 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
16 m²/s²
0-3 km storm-relative helicity
39 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

241 
WGUS56 KHNX 292103
FFWHNX
CAC039-043-292300-
/O.NEW.KHNX.FF.W.0006.210729T2103Z-210729T2300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service San Joaquin Valley CA
203 PM PDT Thu Jul 29 2021

The National Weather Service in Hanford CA has issued a

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

* Until 400 PM PDT.

* At 202 PM PDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Flash flooding is ongoing or
  expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar indicated.

  IMPACT...Flooding of small creeks and streams, urban areas, 
           highways, streets and underpasses as well as other 
           drainage and low lying areas.

* Some locations that will experience flooding include...
  Buck Camp Ranger Station.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, country roads, farmland, and other low lying
spots.

&&

LAT...LON 3770 11924 3744 11931 3746 11956 3772 11947

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-2 INCHES IN 1 HOUR

$$

ab
1 follow-up statement
522 
WGUS76 KHNX 292252
FFSHNX

Flash Flood Statement
National Weather Service San Joaquin Valley CA
352 PM PDT Thu Jul 29 2021

CAC039-043-292300-
/O.EXP.KHNX.FF.W.0006.000000T0000Z-210729T2300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mariposa CA-Madera CA-
352 PM PDT Thu Jul 29 2021

...THE FLASH FLOOD WARNING FOR EAST CENTRAL MARIPOSA AND NORTHEASTERN
MADERA COUNTIES WILL EXPIRE AT 400 PM PDT...

The heavy rain has ended. Flood waters will continue to recede, and 
flash flooding is no longer expected to pose a threat. Please 
continue to heed any remaining road closures.

LAT...LON 3770 11924 3744 11931 3746 11956 3772 11947

$$

CMc

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 28, 5:07 PM PDTFlash Flood WarningHNXMadera, Mariposa, Tuolumne3 min
Jul 28, 5:23 PM PDTFlash Flood WarningHNXMadera, Mariposa, Tuolumne82 min
Jul 28, 7:00 PM PDTSpecial Weather StatementHNXTulare45 min
Jul 29, 9:38 AM PDTFlash Flood WatchHNX58 hr
Jul 29, 1:51 PM PDTSpecial Weather StatementHNXMariposa39 min
Jul 29, 1:52 PM PDTSpecial Weather StatementHNXMariposa38 min
Jul 29, 2:24 PM PDTSpecial Weather StatementHNXTuolumne36 min
Jul 29, 3:07 PM PDTSpecial Weather StatementHNXMariposa38 min
Jul 29, 3:21 PM PDTFlash Flood WarningHNXMariposa, Tuolumne84 min
Jul 29, 3:46 PM PDTFlash Flood WarningHNXMariposa119 min
Jul 29, 4:41 PM PDTAreal Flood AdvisoryHNXMariposa, Tuolumne64 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.