Alert archive / California / Flash Flood Warnings in 2017

Flash Flood Warning 6, NWS San Diego, CA

February 17, 2017Orange County, Riverside County, San Bernardino County, California

NWS San Diego, CA issued this flash flood warning at Feb 17, 2017, 5:12 PM PST for Orange County, Riverside County, San Bernardino County, California. It was in force for 4 hr. 4 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Feb 17, 2017, 5:12 PM PST (01:12 UTC)
Expired
Feb 17, 2017, 9:00 PM PST
In force
4 hr
Issued by
NWS San Diego, CA
Area
Storm-based polygon
Flood severity
None

Counties Orange County, CA, Riverside County, CA, San Bernardino County, CA

The radar

The Santa Ana Mts radar (KSOX), 8 km from the middle of the area, began a volume at 01:14 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.

What was reported inside it

TimeReportWhereRemark
Feb 17, 5:20 PM PSTFLOOD5 E Wrightwood, CAROAD WASHED OUT AND A VEHICLE IS NOW STUCK. .
Feb 17, 5:55 PM PSTFLASH FLOOD7 Sw Mountain View Acre, CALARGE SINK HOLE ON CHATEAU RD/CEDAR ST, JEEP UNDERWATER IN SINKHOLE. .
Feb 17, 6:53 PM PSTFLASH FLOOD3 Se Garden Grove, CAMOBILE HOME COMPLEX FLOODING DUE TO OVERFLOWING OF THE WINTERSBURG CHANNEL.
Feb 17, 8:15 PM PSTFLASH FLOOD9 Ese Wrightwood, CAFIRE TRUCK FELL INTO SINKHOLE ON I-15 AND INTERCHANGE HWY 138, AFTER LANE #5 COLLAPSED DUE TO FLOODING. .

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

San Diego, CA (KNKX), launched 00:00Z, 1.2 hours before the alert went out and 128 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 00:00Z on 2017-02-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 14 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 00:00Z on 2017-02-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 307 square meters per square second.1939587897Sfc1 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
14 J/kg
Mixed-layer CIN
-2 J/kg
Mixed-layer LCL
1020 m above ground
0-6 km bulk shear
63 kt
0-1 km storm-relative helicity
307 m²/s²
0-3 km storm-relative helicity
383 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

638 
WGUS56 KSGX 180112
FFWSGX
CAC059-065-071-180500-
/O.NEW.KSGX.FF.W.0006.170218T0112Z-170218T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service San Diego CA
512 PM PST FRI FEB 17 2017

The National Weather Service in San Diego has issued a

* Flash Flood Warning for...
  Orange County in southwestern California...
  San Bernardino County in southern California...
  Riverside County in southern California...

* Until 900 PM PST

* At 506 PM PST, Doppler radar indicated heavy rain across the
  warned area with the heaviest rain moving onshore the Orange
  County coast which will move east and another area of enhanced
  heavier rain occurring along the coastal mountain slopes of the
  San Bernardino County mountains and through the Cajon Pass.
  Rainfall of 1 to 2 inches has already fallen along the coastal
  mountain slopes with a half to one inch across Orange County.
  Flash flooding will likely begin shortly. In addition, excessive
  rainfall will likely result in debris flows within and downstream
  of the 2016 Blue Cut Fire burn scar, including railways.
  The debris flow can consist of rock, mud, vegetation and other
  loose materials. Highway 138 is closed due to 1 to 2 feet of mud
  covering Lone Pine Road. Rainfall rates of around 1 inch per hour
  will occur in the heaviest bands of rain.

* Some locations that will likely experience flooding include...
  Anaheim, Santa Ana, Riverside, Irvine, San Bernardino, Fontana,
  Huntington Beach, Garden Grove, Ontario, Corona, Orange,
  Fullerton, Costa Mesa, Rialto and Mission Viejo, I-15 Through The
  Cajon Pass, and areas in and around the Blue Cut Fire burn scar.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to higher ground now. Act quickly to protect your life.

&&

LAT...LON 3385 11805 3390 11798 3395 11797 3395 11779
      3398 11780 3402 11777 3402 11773 3420 11767
      3422 11756 3437 11762 3452 11758 3438 11713
      3357 11730 3350 11742 3351 11751 3347 11751
      3345 11758 3340 11759 3354 11779 3374 11812

$$

Gregoria
1 follow-up statement
730 
WGUS76 KSGX 180234
FFSSGX

Flash Flood Statement
National Weather Service San Diego CA
634 PM PST FRI FEB 17 2017

CAC059-065-071-180500-
/O.CON.KSGX.FF.W.0006.000000T0000Z-170218T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Orange CA-San Bernardino CA-Riverside CA-
634 PM PST FRI FEB 17 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 900 PM PST FOR
ORANGE...SAN BERNARDINO AND RIVERSIDE COUNTIES...

At 627 PM PST, Doppler radar indicated heavy rain across the warned
area which will produce flash flooding. Most locations have received
an inch of rain with some locales to around 2 inches. Additional
rain amounts of a quarter to half an inch per hour will result in
flash flooding. In addition, excessive rainfall will likely result
in debris flows within and downstream of the 2016 Blue Cut Fire burn
scar, including railways. The debris flow can consist of rock, mud,
vegetation and other loose materials.

Some locations that will likely experience flooding include...
Anaheim, Santa Ana, Riverside, Irvine, San Bernardino, Fontana,
Huntington Beach, Garden Grove, Ontario, Corona, Orange, Fullerton,
Costa Mesa, Rialto, Mission Viejo, I-15 Through The Cajon Pass, and
areas in and around the Blue Cut Fire burn scar

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be especially cautious at night when it is harder to recognize the
dangers of flooding. Swift moving water is dangerous. Make the smart
choice. Turn around, don't drown.

&&

LAT...LON 3385 11805 3390 11798 3395 11797 3395 11779
      3398 11780 3402 11777 3402 11773 3420 11767
      3422 11756 3437 11762 3452 11758 3438 11713
      3357 11730 3350 11742 3351 11751 3347 11751
      3345 11758 3340 11759 3354 11779 3374 11812

$$

Gregoria

The office that day

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

IssuedProductOfficeCountiesLasted
Feb 17, 4:51 PM PSTSevere Thunderstorm WarningSGXOrange54 min
Feb 17, 5:11 PM PSTSpecial Marine WarningSGX94 min
Feb 17, 5:43 PM PSTSevere Thunderstorm WarningSGXSan Diego62 min
Feb 17, 5:48 PM PSTAreal Flood AdvisorySGXSan Diego5 hr
Feb 17, 5:48 PM PSTSevere Thunderstorm WarningSGXOrange57 min
Feb 17, 6:21 PM PSTFlash Flood WarningSGXSan Bernardino4 hr
Feb 17, 9:00 PM PSTSmall Craft AdvisorySGX49 hr
Feb 17, 10:15 PM PSTAreal Flood WarningSGXRiverside, San Bernardino9 hr
Feb 17, 10:50 PM PSTAreal Flood AdvisorySGXOrange, Riverside, San Diego7 hr

Nearby

Flash Flood Warnings in California, 2017Every flash flood warning in 2017

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.