Alert archive / California / Flash Flood Warnings in 2017

Flash Flood Warning 7, NWS San Diego, CA

February 17, 2017San Bernardino County, California

NWS San Diego, CA issued this flash flood warning at Feb 17, 2017, 6:21 PM PST for San Bernardino County, California. It was in force for 4 hr. 1 report 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, 6:21 PM PST (02:21 UTC)
Expired: Feb 17, 2017, 10:15 PM PST
In force: 4 hr
Issued by: NWS San Diego, CA
Area: Storm-based polygon
Flood severity: None

County San Bernardino County, CA

The radar

The Edwards AFB radar (KEYX), 76 km from the middle of the area, began a volume at 02:21 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

Time	Report	Where	Remark
Feb 17, 8:15 PM PST	FLASH FLOOD	9 Ese Wrightwood, CA	FIRE 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, 2.4 hours before the alert went out and 188 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: 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.

010 
WGUS56 KSGX 180221
FFWSGX
CAC071-180615-
/O.NEW.KSGX.FF.W.0007.170218T0221Z-170218T0615Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in San Diego has issued a

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

* Until 1015 PM PST

* At 615 PM PST, Doppler radar indicated rain across the warned area
  which will produce flash flooding. A half to one inch of rain has
  fallen. Additional moderate rain is expected. Skywarn spotters
  reported a swift water rescue occurring in Victorville already.
  Additional rainfall there and across the high deserts to the
  mountain slopes and the Cajon Pass, including in and around the
  Blue Cut Fire burn scar, will produce flash flooding. Debris flows
  will occur 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...
  Victorville, Hesperia, Apple Valley, Hwy 2 Between Phelan And
  Wrightwood, I-15 Between Victorville And Barstow, I-15 Through The
  Cajon Pass, Lucerne Valley, Lake Arrowhead, Adelanto, Running
  Springs, Hwy 18 Between San Bernardino And Crestline, Crestline,
  Hwy 138 Between I-15 And Hwy 2 and Silverwood Lake Rec Area.

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 3475 11667 3434 11688 3419 11710 3424 11755
      3436 11765 3482 11767

$$

Gregoria

1 follow-up statement

573 
WGUS76 KSGX 180358
FFSSGX

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

CAC071-180615-
/O.CON.KSGX.FF.W.0007.000000T0000Z-170218T0615Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Bernardino CA-
758 PM PST FRI FEB 17 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1015 PM PST FOR
SAN BERNARDINO COUNTY...

At 749 PM PST, Doppler radar indicated rain across the warned area
and an area of heavier rain moving north through the Cajon Pass.
Rates to around a third of an inch per hour will occur. This heavier
rain will only exacerbate ongoing flash flooding. 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...
Victorville, Hesperia, Apple Valley, Wrightwood, Hwy 2 Between Phelan
And Wrightwood, I-15 Between Victorville And Barstow, I-15 Through
The Cajon Pass, Lucerne Valley, Adelanto, Hwy 18 Between San
Bernardino And Crestline, Hwy 138 Between I-15 And Hwy 2 and
Silverwood Lake Rec Area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

&&

LAT...LON 3475 11667 3434 11688 3419 11710 3424 11755
      3436 11765 3482 11767

$$

Gregoria

The office that day

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

Issued	Product	Office	Counties	Lasted
Feb 17, 4:51 PM PST	Severe Thunderstorm Warning	SGX	Orange	54 min
Feb 17, 5:11 PM PST	Special Marine Warning	SGX		94 min
Feb 17, 5:12 PM PST	Flash Flood Warning	SGX	Orange, Riverside, San Bernardino	4 hr
Feb 17, 5:43 PM PST	Severe Thunderstorm Warning	SGX	San Diego	62 min
Feb 17, 5:48 PM PST	Areal Flood Advisory	SGX	San Diego	5 hr
Feb 17, 5:48 PM PST	Severe Thunderstorm Warning	SGX	Orange	57 min
Feb 17, 9:00 PM PST	Small Craft Advisory	SGX		49 hr
Feb 17, 10:15 PM PST	Areal Flood Warning	SGX	Riverside, San Bernardino	9 hr
Feb 17, 10:50 PM PST	Areal Flood Advisory	SGX	Orange, Riverside, San Diego	7 hr

Nearby

Flash Flood Warnings in California, 2017 Every 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.