Alert archive / California / Flash Flood Warnings in 2015

Flash Flood Warning 2, NWS Medford, OR

July 20, 2015Siskiyou County, California

NWS Medford, OR issued this flash flood warning at Jul 20, 2015, 8:09 PM PDT for Siskiyou County, California. It was in force for 3 hr. 2 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
Jul 20, 2015, 8:09 PM PDT (03:09 UTC)
Expired
Jul 20, 2015, 11:00 PM PDT
In force
3 hr
Issued by
NWS Medford, OR
Area
Storm-based polygon
Flood severity
None

County Siskiyou County, CA

The radar

The Medford radar (KMAX), 49 km from the middle of the area, began a volume at 03:09 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
Jul 20, 8:24 PM PDTHEAVY RAIN 1.54 W Grenada, CARAIN FELL IN <90 MINUTES. STANDING WATER. RAINING HEAVILY.
Jul 20, 8:55 PM PDTFLASH FLOOD1 Sw Grenada, CAYREKA DISPATCH REPORTED FLOODING OF HOMES IN GRENADA AND EVACUATIONS OCCURRING AT SHEPARD OF GOD ASSISTED LIVING CENTER IN GRENADA DUE TO WATER ENTERING THE BUILDING.

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

The nearest sounding before it

Medford/Jackson, OR (KMFR), launched 00:00Z, 3.2 hours before the alert went out and 82 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, Medford/Jackson, OR at 00:00Z on 2015-07-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 13 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, Medford/Jackson, OR at 00:00Z on 2015-07-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -16 square meters per square second.193958Sfc1 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
13 J/kg
Mixed-layer CIN
-129 J/kg
Mixed-layer LCL
3153 m above ground
0-6 km bulk shear
5 kt
0-1 km storm-relative helicity
-16 m²/s²
0-3 km storm-relative helicity
23 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

806 
WGUS56 KMFR 210309
FFWMFR
CAC093-210600-
/O.NEW.KMFR.FF.W.0002.150721T0309Z-150721T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MEDFORD OR
809 PM PDT MON JUL 20 2015

THE NATIONAL WEATHER SERVICE IN MEDFORD HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CENTRAL SISKIYOU COUNTY IN NORTHERN CALIFORNIA...

* UNTIL 1100 PM PDT
    
* AT 807 PM PDT...DOPPLER RADAR INDICATED A THUNDERSTORM PRODUCING 
  VERY HEAVY RAIN ACROSS THE WARNED AREA. RADAR ESTIMATES MORE THAN 
  THREE INCHES OF RAIN HAVE ALREADY FALLEN. FLASH FLOODING IS 
  OCCURRING NOW OR EXPECTED TO BEGIN SHORTLY. TRAVELERS ALONG 
  INTERSTATE 5 MAY ENCOUNTER FLOODED ROADWAYS.

* SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  GRENADA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOVE TO HIGHER GROUND NOW. ACT QUICKLY TO PROTECT YOUR LIFE.

STAY AWAY OR BE SWEPT AWAY. RIVER BANKS AND CULVERTS CAN BECOME
UNSTABLE AND UNSAFE. TURN AROUND DON'T DROWN.

&&

LAT...LON 4170 12247 4159 12249 4163 12262 4170 12260

$$

MAS
4 follow-up statements
911 
WGUS76 KMFR 210354
FFSMFR

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MEDFORD OR
854 PM PDT MON JUL 20 2015

CAC093-210600-
/O.CON.KMFR.FF.W.0002.000000T0000Z-150721T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SISKIYOU CA-
854 PM PDT MON JUL 20 2015

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1100 PM PDT FOR
CENTRAL SISKIYOU COUNTY...

AT 850 PM PDT...DOPPLER RADAR INDICATED THUNDERSTORMS THAT WERE 
PRODUCING HEAVY RAIN ACROSS THE WARNED AREA ARE WEAKENING. HOWEVER, 
RADAR ESTIMATES OF OVER THREE INCHES OF RAIN HAVE ALREADY FALLEN. 
FLASH FLOODING IS EXPECTED TO PERSIST AND TRAVELERS ALONG INTERSTATE 
5 MAY ENCOUNTER FLOODED ROADWAYS. LAW ENFORCEMENT REPORTS PORTIONS 
OF OLD HIGHWAY 99 ARE BLOCKED BY FLOODING AND DEBRIS NEAR GRENADA AT 
THE INTERCHANGE WITH INTERSTATE 5. 

SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
GRENADA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOVE TO HIGHER GROUND NOW. ACT QUICKLY TO PROTECT YOUR LIFE.

TURN AROUND...DONT DROWN WHEN ENCOUNTERING FLOODED ROADS. MOST FLOOD
DEATHS OCCUR IN VEHICLES.

&&

LAT...LON 4170 12247 4159 12249 4163 12262 4170 12260

$$

MAS
593 
WGUS76 KMFR 210401
FFSMFR

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MEDFORD OR
901 PM PDT MON JUL 20 2015

CAC093-210600-
/O.CON.KMFR.FF.W.0002.000000T0000Z-150721T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SISKIYOU CA-
901 PM PDT MON JUL 20 2015

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1100 PM PDT FOR
CENTRAL SISKIYOU COUNTY...

AT 858 PM PDT...DOPPLER RADAR INDICATES THE THUNDERSTORMS THAT WERE 
PRODUCING HEAVY RAIN ACROSS THE WARNED AREA CONTINUE TO WEAKEN. 
HOWEVER, RADAR ESTIMATES OF OVER THREE INCHES OF RAIN HAVE ALREADY 
FALLEN. FLASH FLOODING IS EXPECTED TO PERSIST AND TRAVELERS ALONG 
INTERSTATE 5 MAY ENCOUNTER FLOODED ROADWAYS. LAW ENFORCEMENT REPORTS 
PORTIONS OF OLD HIGHWAY 99 ARE BLOCKED BY FLOODING AND DEBRIS NEAR 
GRENADA AT THE INTERCHANGE WITH INTERSTATE 5. FLOODING IS ALSO 
OCCURRING AND EVACUATIONS ARE UNDERWAY AT SHEPHERD OF GOD ASSISTED 
LIVING IN GRENADA. 

SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
GRENADA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOVE TO HIGHER GROUND NOW. ACT QUICKLY TO PROTECT YOUR LIFE.

TURN AROUND...DONT DROWN WHEN ENCOUNTERING FLOODED ROADS. MOST FLOOD
DEATHS OCCUR IN VEHICLES.

&&

LAT...LON 4170 12247 4159 12249 4163 12262 4170 12260

$$

MAS
723 
WGUS76 KMFR 210432
FFSMFR

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MEDFORD OR
932 PM PDT MON JUL 20 2015

CAC093-210600-
/O.CON.KMFR.FF.W.0002.000000T0000Z-150721T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SISKIYOU CA-
932 PM PDT MON JUL 20 2015

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1100 PM PDT FOR
CENTRAL SISKIYOU COUNTY...

AT 929 PM PDT...DOPPLER RADAR INDICATED THE THUNDERSTORMS THAT 
PRODUCED THE HEAVY RAIN ACROSS THE AREA HAVE WEAKENED AND MOVED 
AWAY. RADAR ESTIMATES OF OVER THREE INCHES OF RAIN FELL IN A SHORT 
PERIOD OF TIME EARLIER THIS EVENING CAUSING FLASH FLOODING IN AND 
AROUND GRENADA. WHILE THE HEAVY RAINFALL IS OVER, RESIDUAL FLOODING 
MAY CONTINUE FOR THE NEXT HOUR OR SO. DEBRIS MAY STILL COVER SOME 
ROADWAYS. MOTORISTS SHOULD USE EXTRA CAUTION. 
 
SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...GRENADA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TURN AROUND...DONT DROWN WHEN ENCOUNTERING FLOODED ROADS. MOST FLOOD
DEATHS OCCUR IN VEHICLES.

&&

LAT...LON 4170 12247 4159 12249 4163 12262 4170 12260

$$

MAS
059 
WGUS76 KMFR 210500
FFSMFR

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MEDFORD OR
1000 PM PDT MON JUL 20 2015

CAC093-210510-
/O.CAN.KMFR.FF.W.0002.000000T0000Z-150721T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SISKIYOU CA-
1000 PM PDT MON JUL 20 2015

...THE FLASH FLOOD WARNING FOR CENTRAL SISKIYOU COUNTY IS
CANCELLED...

FLOOD WATERS HAVE RECEDED...AND ARE NO LONGER EXPECTED TO POSE A
THREAT TO LIFE OR PROPERTY. PLEASE CONTINUE TO HEED ANY ROAD
CLOSURES.

LAT...LON 4170 12247 4159 12249 4163 12262 4170 12260

$$

MAS

The office that day

Everything else NWS Medford, OR issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 20, 7:11 PM PDTRed Flag WarningMFRSiskiyou3 hr
Jul 20, 7:15 PM PDTSpecial Weather StatementMFRSiskiyou30 min
Jul 20, 7:29 PM PDTSevere Thunderstorm WarningMFRSiskiyou31 min
Jul 20, 7:56 PM PDTAreal Flood AdvisoryMFRSiskiyou3 hr
Jul 20, 8:29 PM PDTSpecial Weather StatementMFRSiskiyou31 min
Jul 21, 4:07 AM PDTRed Flag WarningMFRModoc, Siskiyou21 hr
Jul 21, 1:09 PM PDTSpecial Weather StatementMFRModoc36 min
Jul 21, 1:55 PM PDTSpecial Weather StatementMFRModoc35 min
Jul 21, 2:08 PM PDTSevere Thunderstorm WarningMFRModoc22 min
Jul 21, 2:33 PM PDTSpecial Weather StatementMFRModoc27 min
Jul 21, 2:44 PM PDTSpecial Weather StatementMFRModoc31 min
Jul 21, 4:37 PM PDTSpecial Weather StatementMFRSiskiyou23 min

Nearby

Flash Flood Warnings in California, 2015Every flash flood warning in 2015

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.