Alert archive / California / Flash Flood Warnings in 2018

Flash Flood Warning 4, NWS San Diego, CA

July 7, 2018Riverside County, San Diego County, California

NWS San Diego, CA issued this flash flood warning at Jul 7, 2018, 2:07 PM PDT for Riverside County, San Diego County, California. It was in force for 3 hr. 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 7, 2018, 2:07 PM PDT (21:07 UTC)
Expired
Jul 7, 2018, 5:00 PM PDT
In force
3 hr
Issued by
NWS San Diego, CA
Area
Storm-based polygon
Flood severity
None

Counties Riverside County, CA, San Diego County, CA

The radar

The San Diego radar (KNKX), 57 km from the middle of the area, began a volume at 21:10 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, 9.1 hours before the alert went out and 74 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 2018-07-07Temperature 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, San Diego, CA at 12:00Z on 2018-07-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -6 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
3366 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
-6 m²/s²
0-3 km storm-relative helicity
3 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

253 
WGUS56 KSGX 072107
FFWSGX
CAC065-073-080000-
/O.NEW.KSGX.FF.W.0004.180707T2107Z-180708T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service San Diego CA
207 PM PDT SAT JUL 7 2018

The National Weather Service in San Diego has issued a

* Flash Flood Warning for...
  Riverside County in southern California...
  North central San Diego County in southwestern California...

* Until 500 PM PDT

* At 206 PM PDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Flash flooding will likely begin
  shortly.

* Some locations that will likely experience flooding include...
  Aguanga, Hwy 79 Between Warner Springs And Oak Grove, Palomar
  Mountain State Park, Palomar Mountain, S7 - East Grade Rd, Hwy 79
  Between Oak Grove And Aguanga, Pauma Indian Reservation, Oak Grove,
  La Jolla Indian Reservation and Pauma Valley.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3351 11685 3332 11669 3326 11676 3335 11699
      3348 11701

$$

JJT
2 follow-up statements
331 
WGUS76 KSGX 072150
FFSSGX

Flash Flood Statement
National Weather Service San Diego CA
250 PM PDT SAT JUL 7 2018

CAC065-073-080000-
/O.CON.KSGX.FF.W.0004.000000T0000Z-180708T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Riverside CA-San Diego CA-
250 PM PDT SAT JUL 7 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 500 PM PDT FOR
RIVERSIDE AND NORTH CENTRAL SAN DIEGO COUNTIES...

At 247 PM PDT, Doppler radar indicated thunderstorms have diminished 
for the time being, however additional storms are expected over the 
next few hours. The threat for flash flooding will continue for the 
area through 500 PM.

Some locations that will experience likely flooding include...
Aguanga, Hwy 79 Between Warner Springs And Oak Grove, Palomar
Mountain State Park, Palomar Mountain, S7 - East Grade Rd, Hwy 79
Between Oak Grove And Aguanga, Pauma Indian Reservation, Oak Grove,
La Jolla Indian Reservation and Pauma Valley.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.

&&

LAT...LON 3351 11685 3332 11669 3326 11676 3335 11699
      3348 11701

$$

JJT
394 
WGUS76 KSGX 072351
FFSSGX

Flash Flood Statement
National Weather Service San Diego CA
451 PM PDT SAT JUL 7 2018

CAC065-073-080000-
/O.EXP.KSGX.FF.W.0004.000000T0000Z-180708T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Riverside CA-San Diego CA-
451 PM PDT SAT JUL 7 2018

...THE FLASH FLOOD WARNING FOR RIVERSIDE AND NORTH CENTRAL SAN DIEGO
COUNTIES WILL EXPIRE AT 500 PM PDT...

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

LAT...LON 3351 11685 3332 11669 3326 11676 3335 11699
      3348 11701

$$

JJT

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 7, 12:43 PM PDTFlash Flood WarningSGXSan Bernardino3 hr
Jul 7, 12:56 PM PDTFlash Flood WarningSGXSan Bernardino3 hr

Nearby

Flash Flood Warnings in California, 2018Every flash flood warning in 2018

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.