Alert archive / California / Flood Watches in 2017

Flood Watch 8, NWS Eureka, CA

November 19, 2017Del Norte County, Humboldt County, Trinity County, California

NWS Eureka, CA issued this flood watch at Nov 19, 2017, 2:22 PM PST for Del Norte County, Humboldt County, Trinity County, California. It took effect at Nov 19, 2017, 10:00 PM PST. It was in force for 21 hr.

The area

The counties it named.

The facts

Issued
Nov 19, 2017, 2:22 PM PST (22:22 UTC)
In effect from
Nov 19, 2017, 10:00 PM PST
Expired
Nov 20, 2017, 7:03 PM PST
In force
21 hr
Issued by
NWS Eureka, CA

Counties Del Norte County, CA, Humboldt County, CA, Trinity County, CA

The radar

The Eureka (Bunker Hill) radar (KBHX), 80 km from the middle of the area, began a volume at 22:22 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

Medford/Jackson, OR (KMFR), launched 12:00Z, 10.4 hours before the alert went out and 165 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 12:00Z on 2017-11-19Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Medford/Jackson, OR at 12:00Z on 2017-11-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 58 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
812 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
58 m²/s²
0-3 km storm-relative helicity
189 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

105 
WGUS66 KEKA 192222
FFAEKA

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Eureka CA
222 PM PST Sun Nov 19 2017

CAZ102-104>108-200630-
/O.NEW.KEKA.FA.A.0002.171120T0600Z-171121T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Del Norte Interior-Southwestern Humboldt-
Northern Humboldt Interior-Southern Humboldt Interior-
Northern Trinity-Southern Trinity-
222 PM PST Sun Nov 19 2017

...FLOOD WATCH IN EFFECT FROM 10 PM PST THIS EVENING THROUGH
MONDAY EVENING...

The National Weather Service in Eureka has issued a

* Flood Watch for a portion of northwest California, including 
  the following areas, Del Norte Interior, Northern Humboldt 
  Interior, Northern Trinity, Southern Humboldt Interior, 
  Southern Trinity, and Southwestern Humboldt. 

* From 10 PM PST this evening through Monday evening

* Heavy rain is forecast to occur during Monday with storm total
  rainfall possibly exceeding 5 inches across westward facing
  mountain slopes. The heavy rainfall may lead to urban and small
  stream flooding. In addition, mountain rock and mud slides will
  be possible, including areas around the Trinity County burn 
  scar near Helena.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flood Watch means there is a potential for flooding based on
current forecasts.

You should monitor later forecasts and be alert for possible
Flood Warnings. Those living in areas prone to flooding should be
prepared to take action should flooding develop.

&&

$$
5 follow-up statements
270 
WGUS66 KEKA 200601
FFAEKA

Flood Watch
National Weather Service Eureka CA
1001 PM PST Sun Nov 19 2017

CAZ102-104>108-201400-
/O.CON.KEKA.FA.A.0002.000000T0000Z-171121T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Del Norte Interior-Southwestern Humboldt-
Northern Humboldt Interior-Southern Humboldt Interior-
Northern Trinity-Southern Trinity-
1001 PM PST Sun Nov 19 2017

...FLOOD WATCH REMAINS IN EFFECT THROUGH MONDAY EVENING...

The Flood Watch continues for

* A portion of northwest California, including the following 
  areas, Del Norte Interior, Northern Humboldt Interior, 
  Northern Trinity, Southern Humboldt Interior, Southern 
  Trinity, and Southwestern Humboldt. 

* Through Monday evening

* Heavy rain is forecast to occur during Monday with storm total
  rainfall possibly exceeding 5 inches across westward facing
  mountain slopes. The heavy rainfall may lead to urban and small
  stream flooding. In addition, mountain rock and mud slides will
  be possible, including areas around the Trinity County burn scar
  near Helena. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flood Watch means there is a potential for flooding based on
current forecasts.

You should monitor later forecasts and be alert for possible
Flood Warnings. Those living in areas prone to flooding should be
prepared to take action should flooding develop.

&&

$$
724 
WGUS66 KEKA 201255
FFAEKA

Flood Watch
National Weather Service Eureka CA
455 AM PST Mon Nov 20 2017

CAZ102-104>106-202100-
/O.CON.KEKA.FA.A.0002.000000T0000Z-171121T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Del Norte Interior-Southwestern Humboldt-
Northern Humboldt Interior-Southern Humboldt Interior-
455 AM PST Mon Nov 20 2017

...FLOOD WATCH REMAINS IN EFFECT THROUGH THIS EVENING...

The Flood Watch continues for

* A portion of northwest California, including the following 
  areas, Del Norte Interior, Northern Humboldt Interior, 
  Southern Humboldt Interior, and Southwestern Humboldt. 

* Through this evening

* Heavy rain will continue today with storm total rainfall amounts
  exceeding 5 inches possible across westward facing mountain 
  slopes.

* The heavy rainfall may lead to urban and small stream flooding.
  In addition rock and mud slides will be possible in steep
  terrain.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flood Watch means there is a potential for flooding based on
current forecasts.

You should monitor later forecasts and be alert for possible
Flood Warnings. Those living in areas prone to flooding should be
prepared to take action should flooding develop.

&&

$$

CAZ107-108-202100-
/O.CON.KEKA.FA.A.0002.000000T0000Z-171121T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Northern Trinity-Southern Trinity-
455 AM PST Mon Nov 20 2017

...FLOOD WATCH REMAINS IN EFFECT THROUGH THIS EVENING...

The Flood Watch continues for

* A portion of northwest California, including the following 
  areas, Northern Trinity and Southern Trinity. 

* Through this evening

* Moderate to heavy rain will continue today with storm total 
  rainfall amounts exceeding 3 inches possible on westward facing 
  mountain slopes.
 
* There is an increased potential for flooding along with rock or
  land slides in and below burn scars. Hourly rainfall rates 
  could exceed a half inch per hour at times during the upcoming 
  storm. Severely burned areas are of particular concern.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flood Watch means there is a potential for flooding based on
current forecasts.

You should monitor later forecasts and be alert for possible
Flood Warnings. Those living in areas prone to flooding should be
prepared to take action should flooding develop.

&&

$$
496 
WGUS66 KEKA 201535
FFAEKA

Flood Watch
National Weather Service Eureka CA
735 AM PST Mon Nov 20 2017

CAZ102-104>106-202345-
/O.CON.KEKA.FA.A.0002.000000T0000Z-171121T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Del Norte Interior-Southwestern Humboldt-
Northern Humboldt Interior-Southern Humboldt Interior-
735 AM PST Mon Nov 20 2017

...FLOOD WATCH REMAINS IN EFFECT THROUGH THIS EVENING...

The Flood Watch continues for

* A portion of northwest California, including the following 
  areas, Del Norte Interior, Northern Humboldt Interior, 
  Southern Humboldt Interior, and Southwestern Humboldt. 

* Through this evening

* Heavy rain will continue today, with storm total rainfall 
  amounts exceeding 5 inches across westward facing mountain 
  slopes. 

* The heavy rainfall may lead to urban and small stream 
  flooding. In addition rock and mud slides will be possible in 
  steep terrain. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flood Watch means there is a potential for flooding based on
current forecasts.

You should monitor later forecasts and be alert for possible
Flood Warnings. Those living in areas prone to flooding should be
prepared to take action should flooding develop.

&&

$$

CAZ107-108-202345-
/O.CON.KEKA.FA.A.0002.000000T0000Z-171121T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Northern Trinity-Southern Trinity-
735 AM PST Mon Nov 20 2017

...FLOOD WATCH REMAINS IN EFFECT THROUGH THIS EVENING...

The Flood Watch continues for

* A portion of northwest California, including the following 
  areas, Northern Trinity and Southern Trinity. 

* Through this evening

* Moderate to heavy rain will continue today with storm total
  rainfall amounts exceeding 3 inches over westward facing 
  mountain slopes. 

* There is an increased potential for flooding along with rock 
  or land slides in and below burn scars. Hourly rainfall rates 
  could exceed a half inch per hour at times during the upcoming 
  storm. Severely burned areas are of particular concern. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flood Watch means there is a potential for flooding based on
current forecasts.

You should monitor later forecasts and be alert for possible
Flood Warnings. Those living in areas prone to flooding should be
prepared to take action should flooding develop.

&&

$$
622 
WGUS66 KEKA 202217
FFAEKA

Flood Watch
National Weather Service Eureka CA
217 PM PST Mon Nov 20 2017

CAZ102-104>106-210600-
/O.CON.KEKA.FA.A.0002.000000T0000Z-171121T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Del Norte Interior-Southwestern Humboldt-
Northern Humboldt Interior-Southern Humboldt Interior-
217 PM PST Mon Nov 20 2017

...FLOOD WATCH REMAINS IN EFFECT UNTIL 10 PM PST THIS EVENING...

The Flood Watch continues for

* A portion of northwest California, including the following 
  areas, Del Norte Interior, Northern Humboldt Interior, 
  Southern Humboldt Interior, and Southwestern Humboldt. 

* Until 10 PM PST this evening

* Heavy rain will continue this evening, with an additional 1 to 
  3 inches of rain expected across westward facing mountain 
  slopes. 

* The heavy rainfall may lead to urban and small stream 
  flooding. In addition rock and mud slides will be possible in 
  steep terrain. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flood Watch means there is a potential for flooding based on
current forecasts.

You should monitor later forecasts and be alert for possible
Flood Warnings. Those living in areas prone to flooding should be
prepared to take action should flooding develop.

&&

$$

CAZ107-108-210600-
/O.CON.KEKA.FA.A.0002.000000T0000Z-171121T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Northern Trinity-Southern Trinity-
217 PM PST Mon Nov 20 2017

...FLOOD WATCH REMAINS IN EFFECT UNTIL 10 PM PST THIS EVENING...

The Flood Watch continues for

* A portion of northwest California, including the following 
  areas, Northern Trinity and Southern Trinity. 

* Until 10 PM PST this evening

* Moderate to heavy rain will continue this evening, with an
  additional 1 to 2 inches of rain expected across westward 
  facing mountain slopes.

* There is an increased potential for small stream flooding along
  with rock or mud slides in and below burn scars.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flood Watch means there is a potential for flooding based on
current forecasts.

You should monitor later forecasts and be alert for possible
Flood Warnings. Those living in areas prone to flooding should be
prepared to take action should flooding develop.

&&

$$
226 
WGUS66 KEKA 210303
FFAEKA

Flood Watch
National Weather Service Eureka CA
703 PM PST Mon Nov 20 2017

CAZ102-104>108-210415-
/O.CAN.KEKA.FA.A.0002.000000T0000Z-171121T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Del Norte Interior-Southwestern Humboldt-
Northern Humboldt Interior-Southern Humboldt Interior-
Northern Trinity-Southern Trinity-
703 PM PST Mon Nov 20 2017

...FLOOD WATCH IS CANCELLED...

The Flood Watch for portions of northwest California has been 
cancelled. Areas of light rain will continue to fall through
the evening hours but will diminish greatly by midnight.  

$$

Nearby

Flood Watches in California, 2017Every flood watch 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.