Alert archive / California / Flash Flood Warnings in 2025

Flash Flood Warning 16, NWS Los Angeles, CA

July 18, 2025Los Angeles County, California

NWS Los Angeles, CA issued this flash flood warning at Jul 18, 2025, 4:30 PM PDT for Los Angeles County, California. It was in force for 118 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
Jul 18, 2025, 4:30 PM PDT (23:30 UTC)
Expired
Jul 18, 2025, 6:28 PM PDT
In force
118 min
Issued by
NWS Los Angeles, CA
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

County Los Angeles County, CA

The radar

The Santa Ana Mts radar (KSOX), 71 km from the middle of the area, began a volume at 23:32 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, 11.5 hours before the alert went out and 184 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 12:00Z on 2025-07-18Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, San Diego, CA at 12:00Z on 2025-07-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 19 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
788 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
19 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 office that day

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

IssuedProductOfficeCountiesLasted
Jul 18, 2:09 PM PDTAreal Flood AdvisoryLOXLos Angeles3 hr
Jul 18, 2:47 PM PDTFlash Flood Warning Considerable damage threatLOXLos Angeles3 hr
Jul 18, 2:56 PM PDTSpecial Weather StatementLOXLos Angeles64 min
Jul 18, 3:06 PM PDTSpecial Weather StatementLOXVentura24 min
Jul 18, 4:04 PM PDTAreal Flood AdvisoryLOXLos Angeles104 min
Jul 18, 4:18 PM PDTSpecial Weather StatementLOX27 min
Jul 18, 4:45 PM PDTSpecial Weather StatementLOX60 min

Nearby

Flash Flood Warnings in California, 2025Every flash flood warning in 2025

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.