Alert archive / California / Flood Watches in 2017

Flood Watch 5, NWS Eureka, CA

February 15, 2017Humboldt County, Mendocino County, California

NWS Eureka, CA issued this flood watch at Feb 15, 2017, 2:32 PM PST for Humboldt County, Mendocino County, California. It took effect at Feb 15, 2017, 7:00 PM PST. It was in force for 14 hr.

The area

The counties it named.

The facts

Issued
Feb 15, 2017, 2:32 PM PST (22:32 UTC)
In effect from
Feb 15, 2017, 7:00 PM PST
Expired
Feb 16, 2017, 9:06 AM PST
In force
14 hr
Issued by
NWS Eureka, CA
Flood severity
None

Counties Humboldt County, CA, Mendocino County, CA

The radar

The Eureka (Bunker Hill) radar (KBHX), 71 km from the middle of the area, began a volume at 22:32 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, 10.5 hours before the alert went out and 266 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 2017-02-15Temperature 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 2017-02-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 127 square meters per square second.19395878Sfc1 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
2205 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
127 m²/s²
0-3 km storm-relative helicity
413 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

896 
WGUS66 KEKA 152232
FFAEKA

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Eureka CA
232 PM PST Wed Feb 15 2017

A period of heavy rain is forecast to occur tonight as a frontal 
boundary moves east across the region.

CAZ104-106-109>113-160645-
/O.NEW.KEKA.FA.A.0005.170216T0300Z-170216T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Southwestern Humboldt-Southern Humboldt Interior-Mendocino Coast-
Northwestern Mendocino Interior-Northeastern Mendocino Interior-
Southwestern Mendocino Interior-Southeastern Mendocino Interior-
232 PM PST Wed Feb 15 2017

...FLOOD WATCH IN EFFECT FROM 7 PM PST THIS EVENING THROUGH
THURSDAY MORNING...

The National Weather Service in Eureka has issued a

* Flood Watch for a portion of northwest California, including 
  the following areas, Mendocino Coast, Northeastern Mendocino 
  Interior, Northwestern Mendocino Interior, Southeastern 
  Mendocino Interior, Southern Humboldt Interior, Southwestern 
  Humboldt, and Southwestern Mendocino Interior. 

* From 7 PM PST this evening through Thursday morning

* Rainfall amounts from 2 to 4 inches are forecast to occur during
  Wednesday night. Highest amounts are expected along southwest 
  facing mountain slopes.

* Primary impacts will be localized ponding of water on low lying
  roadways with poor drainage...as well as rising water level for
  area streams. Flooding near the coast will be enhanced during
  high tide. In addition...heavy rain combined with gusty winds
  will increase the potential for rock and mud slides on mountain
  roads.

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.

&&

$$
2 follow-up statements
712 
WGUS66 KEKA 160652
FFAEKA

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Eureka CA
1052 PM PST Wed Feb 15 2017

A period of heavy rain is forecast to occur tonight as a frontal
boundary moves east across the region.

CAZ104-106-109>113-161800-
/O.EXT.KEKA.FA.A.0005.000000T0000Z-170216T1800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Southwestern Humboldt-Southern Humboldt Interior-Mendocino Coast-
Northwestern Mendocino Interior-Northeastern Mendocino Interior-
Southwestern Mendocino Interior-Southeastern Mendocino Interior-
1052 PM PST Wed Feb 15 2017

...GENERAL FLOOD WATCH NOW IN EFFECT UNTIL 10 AM PST THURSDAY...

The Flood Watch is now in effect for

* A portion of northwest California, including the following 
  areas, Mendocino Coast, Northeastern Mendocino Interior, 
  Northwestern Mendocino Interior, Southeastern Mendocino 
  Interior, Southern Humboldt Interior, Southwestern Humboldt, 
  and Southwestern Mendocino Interior. 

* Until 10 AM PST Thursday

* Rainfall amounts from 2 to 4 inches are forecast to occur
  OVERNIGHT. Highest amounts are expected along southwest facing 
  mountain slopes. 

* Primary impacts will be localized ponding of water on low 
  lying roadways with poor drainage...as well as rising water 
  level for area streams. Flooding near the coast will be 
  enhanced during high tide. In addition...heavy rain combined 
  with gusty winds will increase the potential for rock and mud 
  slides on mountain roads. 

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.

&&

$$
444 
WGUS66 KEKA 161706
FFAEKA

Flood Watch
National Weather Service Eureka CA
906 AM PST Thu Feb 16 2017

CAZ104-106-109>113-161815-
/O.CAN.KEKA.FA.A.0005.000000T0000Z-170216T1800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Southwestern Humboldt-Southern Humboldt Interior-Mendocino Coast-
Northwestern Mendocino Interior-Northeastern Mendocino Interior-
Southwestern Mendocino Interior-Southeastern Mendocino Interior-
906 AM PST Thu Feb 16 2017

...FLOOD WATCH IS CANCELLED...

The Flood Watch for a portion of northwest California has been
cancelled. Heavy rain has moved east away from the region and the
threat for flooding in low lying areas and small streams has come
to an end.

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Feb 15, 2:52 AM PSTWind AdvisoryEKADel Norte, Humboldt25 hr
Feb 15, 3:16 AM PSTGale WarningEKA24 hr

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.