Alert archive / California / Flash Flood Warnings in 2020

Flash Flood Warning 14, NWS Hanford, CA

August 18, 2020Tulare County, California

NWS Hanford, CA issued this flash flood warning at Aug 18, 2020, 3:38 PM PDT for Tulare County, California. It was in force for 92 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Aug 18, 2020, 3:38 PM PDT (22:38 UTC)
Expired: Aug 18, 2020, 5:10 PM PDT
In force: 92 min
Issued by: NWS Hanford, CA
Area: Storm-based polygon
Flood severity: None

County Tulare County, CA

The radar

The San Joaquin Valley radar (KHNX), 75 km from the middle of the area, began a volume at 22:40 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

Las Vegas, NV (KVEF), launched 12:00Z, 10.6 hours before the alert went out and 293 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 98 J/kg
Mixed-layer CIN: -332 J/kg
Mixed-layer LCL: 3955 m above ground
0-6 km bulk shear: 8 kt
0-1 km storm-relative helicity: -10 m²/s²
0-3 km storm-relative helicity: -13 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Hanford, CA wrote its last area forecast discussion before this flash flood warning went out at Aug 18, 2:34 PM PDT, 1 hour 4 minutes earlier.

Area forecast discussion, Aug 18, 2:34 PM PDT, 1 hour 4 minutes before

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In the hours before

Local storm report, Aug 18, 10:00 AM PDT, 5 hours 38 minutes before

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Special weather statement, Aug 18, 3:13 PM PDT, 25 minutes before

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Special weather statement, Aug 18, 3:35 PM PDT, 3 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 17, 5:05 PM PDT	Severe Thunderstorm Warning	HNX	Fresno, Madera, Mariposa, Tuolumne	55 min
Aug 17, 5:48 PM PDT	Special Weather Statement	HNX	Mono	57 min
Aug 17, 6:11 PM PDT	Severe Thunderstorm Warning	HNX	Mariposa, Tuolumne	34 min
Aug 18, 12:30 PM PDT	Flash Flood Watch	HNX		7 hr
Aug 18, 3:13 PM PDT	Special Weather Statement	HNX		47 min
Aug 18, 3:35 PM PDT	Special Weather Statement	HNX		40 min
Aug 18, 3:48 PM PDT	Areal Flood Advisory	HNX	Kern	38 min
Aug 18, 3:57 PM PDT	Areal Flood Advisory	HNX	Kern	94 min
Aug 18, 4:14 PM PDT	Special Weather Statement	HNX		31 min
Aug 18, 4:21 PM PDT	Flash Flood Warning	HNX	Kern	114 min
Aug 18, 4:32 PM PDT	Special Weather Statement	HNX	Kern	28 min
Aug 18, 4:44 PM PDT	Special Weather Statement	HNX		31 min
Aug 18, 4:55 PM PDT	Special Weather Statement	HNX	Tulare	50 min

Nearby

Flash Flood Warnings in California, 2020 Every flash flood warning in 2020

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.