Alert archive / California / Flood Watches in 2021

Flood Watch 2, NWS Eureka, CA

January 29, 20214 counties in California

NWS Eureka, CA issued this flood watch at Jan 29, 2021, 4:52 PM PST for 4 counties in California. It took effect at Jan 30, 2021, 10:00 PM PST. It was in force for 6 hr.

The area

The counties it named.

The facts

Issued
Jan 29, 2021, 4:52 PM PST (00:52 UTC)
In effect from
Jan 30, 2021, 10:00 PM PST
Expired
Jan 31, 2021, 4:28 AM PST
In force
6 hr
Issued by
NWS Eureka, CA
Flood severity
None

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

The radar

The Eureka (Bunker Hill) radar (KBHX), 60 km from the middle of the area, began a volume at 00:51 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 00:00Z, 0.9 hours before the alert went out and 204 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 2021-01-30Temperature 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 00:00Z on 2021-01-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 95 square meters per square second.1939587897117Sfc1 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
953 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
95 m²/s²
0-3 km storm-relative helicity
154 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

402 
WGUS66 KEKA 300052
FFAEKA

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Eureka CA
452 PM PST Fri Jan 29 2021

.A warm and moist air mass will spread across northwest California 
Saturday night through Monday night. A long duration of heavy rain 
will be possible as a result.

CAZ101>106-108>113-300900-
/O.NEW.KEKA.FA.A.0002.210131T0600Z-210202T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Coastal Del Norte-Del Norte Interior-Northern Humboldt Coast-
Southwestern Humboldt-Northern Humboldt Interior-Southern Humboldt
Interior-Southern Trinity-Mendocino Coast-Northwestern Mendocino
Interior-Northeastern Mendocino Interior-Southwestern Mendocino
Interior-Southeastern Mendocino Interior-
452 PM PST Fri Jan 29 2021

...FLOOD WATCH IN EFFECT FROM SATURDAY EVENING THROUGH LATE MONDAY 
NIGHT...

The National Weather Service in Eureka has issued a

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

* From Saturday evening through late Monday night

* Three to five inches of rain is expected Saturday night through 
  Monday night across most coastal and valley locations, with higher 
  amounts from six to nine inches possible across southwest facing 
  mountains and ridges. Heavy rain combined with saturated soil and 
  melting snow across the mountains will contribute toward possible 
  flooding.

* Low lying areas, creeks, streams, culverts, and portions of urban 
  areas may experience flooding due to heavy rainfall.

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.

&&

$$

JMG
6 follow-up statements
361 
WGUS66 KEKA 300558
FFAEKA

Flood Watch
National Weather Service Eureka CA
958 PM PST Fri Jan 29 2021

.A warm and moist air mass will spread across northwest California 
Saturday night through Monday night. A long duration of heavy rain 
will be possible as a result.

CAZ101>106-108>113-301400-
/O.CON.KEKA.FA.A.0002.210131T0600Z-210202T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Coastal Del Norte-Del Norte Interior-Northern Humboldt Coast-
Southwestern Humboldt-Northern Humboldt Interior-Southern Humboldt
Interior-Southern Trinity-Mendocino Coast-Northwestern Mendocino
Interior-Northeastern Mendocino Interior-Southwestern Mendocino
Interior-Southeastern Mendocino Interior-
958 PM PST Fri Jan 29 2021

...FLOOD WATCH REMAINS IN EFFECT FROM SATURDAY EVENING THROUGH LATE 
MONDAY NIGHT...

The Flood Watch continues for

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

* From Saturday evening through late Monday night

* Three to five inches of rain is expected Saturday night through 
  Monday night across coastal and valley locations, with higher 
  amounts from six to nine inches possible across southwest facing 
  mountains and ridges. Heavy rain combined with saturated soil and 
  melting snow across the mountains will contribute toward possible 
  flooding.

* Low lying areas, creeks, streams, culverts, and portions of urban 
  areas may experience flooding due to heavy rainfall.

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.

&&

$$

JMG
391 
WGUS66 KEKA 300703
FFAEKA

Flood Watch
National Weather Service Eureka CA
1103 PM PST Fri Jan 29 2021

.A warm and moist air mass will spread across northwest California 
Saturday night through Monday night. A long duration of heavy rain 
will be possible as a result.

CAZ101>106-108>113-301515-
/O.CON.KEKA.FA.A.0002.210131T0600Z-210202T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Coastal Del Norte-Del Norte Interior-Northern Humboldt Coast-
Southwestern Humboldt-Northern Humboldt Interior-Southern Humboldt
Interior-Southern Trinity-Mendocino Coast-Northwestern Mendocino
Interior-Northeastern Mendocino Interior-Southwestern Mendocino
Interior-Southeastern Mendocino Interior-
1103 PM PST Fri Jan 29 2021

...FLOOD WATCH REMAINS IN EFFECT FROM SATURDAY EVENING THROUGH LATE 
MONDAY NIGHT...

The Flood Watch continues for

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

* From Saturday evening through late Monday night

* Three to five inches of rain is expected Saturday night through 
  Monday night across coastal and valley locations, with higher 
  amounts from six to nine inches possible across southwest facing 
  mountains and ridges. Heavy rain combined with saturated soil and 
  melting snow across the mountains will contribute toward possible 
  flooding.

* Low lying areas, creeks, streams, culverts, and portions of urban 
  areas may experience flooding due to heavy rainfall.

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.

&&

$$

JMG
039 
WGUS66 KEKA 301341
FFAEKA

Flood Watch
National Weather Service Eureka CA
541 AM PST Sat Jan 30 2021

.A warm and moist air mass will spread across northwest California 
Saturday night through Monday night. A long duration of heavy rain 
will be possible as a result.

CAZ101>106-108>113-302145-
/O.CON.KEKA.FA.A.0002.210131T0600Z-210202T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Coastal Del Norte-Del Norte Interior-Northern Humboldt Coast-
Southwestern Humboldt-Northern Humboldt Interior-Southern Humboldt
Interior-Southern Trinity-Mendocino Coast-Northwestern Mendocino
Interior-Northeastern Mendocino Interior-Southwestern Mendocino
Interior-Southeastern Mendocino Interior-
541 AM PST Sat Jan 30 2021

...FLOOD WATCH REMAINS IN EFFECT FROM THIS EVENING THROUGH LATE 
MONDAY NIGHT...

The Flood Watch continues for

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

* From this evening through late Monday night

* Three to five inches of rain is expected Saturday night through 
  Monday night across coastal and valley locations, with higher 
  amounts from six to nine inches possible across southwest facing 
  mountains and ridges. Heavy rain combined with saturated soil and 
  melting snow across the mountains will contribute toward possible 
  flooding.

* Low lying areas, creeks, streams, culverts, and portions of urban 
  areas may experience flooding due to heavy rainfall.

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.

&&

$$

JJW
399 
WGUS66 KEKA 302211
FFAEKA

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Eureka CA
211 PM PST Sat Jan 30 2021

.An atmospheric river will focus near the northwest California
coast much of Sunday and Monday, before shifting eastward across
our area with a cold front late Monday or Monday night. Periods of
moderate to heavy rainfall will result, on top of areas where
soils have been saturated from recent rains, and heavy snowpack is
present. The focus of the heavier rain has shifted a bit farther
north and west though, lowering the threat for much of Mendocino
County. 


CAZ112-113-302315-
/O.CAN.KEKA.FA.A.0002.210131T0600Z-210202T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Southwestern Mendocino Interior-Southeastern Mendocino Interior-
211 PM PST Sat Jan 30 2021

...FLOOD WATCH IS CANCELLED...

The Flood Watch for a portion of northwest California has been
cancelled. While 1 to 2 inches of rainfall is still expected
Sunday and Monday, lower rainfall rates will mitigate the threat
of minor flooding concerns. 

$$

CAZ101>106-108>111-310615-
/O.EXT.KEKA.FA.A.0002.210131T1200Z-210202T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Coastal Del Norte-Del Norte Interior-Northern Humboldt Coast-
Southwestern Humboldt-Northern Humboldt Interior-
Southern Humboldt Interior-Southern Trinity-Mendocino Coast-
Northwestern Mendocino Interior-Northeastern Mendocino Interior-
211 PM PST Sat Jan 30 2021

...FLOOD WATCH NOW IN EFFECT FROM LATE TONIGHT THROUGH LATE
MONDAY NIGHT...

The Flood Watch is now in effect for

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

* From late tonight through late Monday night

* 2 to 4 inches of rain is expected from tonight through Monday
  night across coastal and valley locations. Locally over 5 inches
  around coastal Del Norte and southwest Humboldt. 5 to 9 inches
  expected across southwest facing mountains and ridges. Heavy 
  rain combined with saturated soil and melting snow across the 
  mountains will contribute toward possible flooding. 

* Low lying areas, creeks, streams, culverts, and portions of 
  urban areas may experience flooding due to heavy rainfall. 

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.

&&

$$
578 
WGUS66 KEKA 310521
FFAEKA

Flood Watch
National Weather Service Eureka CA
921 PM PST Sat Jan 30 2021

.An atmospheric river will focus near the northwest California
coast much of Sunday and Monday, before shifting eastward across
our area with a cold front late Monday or Monday night. Periods of
moderate to heavy rainfall will result, on top of areas where
soils have been saturated from recent rains, and heavy snowpack is
present. The focus of the heavier rain has shifted a bit farther
north and west though, lowering the threat for much of Mendocino
County.

CAZ101>106-108>111-311415-
/O.CON.KEKA.FA.A.0002.210131T0600Z-210202T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Coastal Del Norte-Del Norte Interior-Northern Humboldt Coast-
Southwestern Humboldt-Northern Humboldt Interior-Southern Humboldt
Interior-Southern Trinity-Mendocino Coast-Northwestern Mendocino
Interior-Northeastern Mendocino Interior-
921 PM PST Sat Jan 30 2021

...FLOOD WATCH REMAINS IN EFFECT THROUGH LATE MONDAY NIGHT...

The Flood Watch continues for

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

* Through late Monday night

* 2 To 4 inches of rain is expected from tonight through Monday 
  night across coastal and valley locations. 5 to 7 inches
  expected across southwest facing mountains and ridges. Heavy 
  rain combined with saturated soil and melting snow across the 
  mountains will contribute toward possible flooding.

* Low lying areas, creeks, streams, culverts, and portions of urban 
  areas may experience flooding due to heavy rainfall.

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.

&&

$$

CB
713 
WGUS66 KEKA 311228
FFAEKA

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Eureka CA
428 AM PST Sun Jan 31 2021



.An atmospheric river will focus near the northwest California
coast much of Sunday and Monday, before shifting eastward across
our area with a cold front late Monday or Monday night. Periods of
moderate to heavy rainfall will result, on top of areas where
soils have been saturated from recent rains, and heavy snowpack is
present. The focus of the heavier rain has shifted a bit farther
north and west though, lowering the threat for much of Mendocino
County.

CAZ101>106-108>111-312030-
/O.CAN.KEKA.FA.A.0002.000000T0000Z-210202T1200Z/
/O.NEW.KEKA.FA.A.0003.210131T1800Z-210202T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Coastal Del Norte-Del Norte Interior-Northern Humboldt Coast-
Southwestern Humboldt-Northern Humboldt Interior-
Southern Humboldt Interior-Southern Trinity-Mendocino Coast-
Northwestern Mendocino Interior-Northeastern Mendocino Interior-
428 AM PST Sun Jan 31 2021

...FLOOD WATCH IN EFFECT FROM 10 AM PST THIS MORNING THROUGH LATE
MONDAY NIGHT...

The National Weather Service in Eureka has issued a

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

* From 10 AM PST this morning through late Monday night

*  2 to 4 inches of rain is expected from today through Monday 
   night across coastal and valley locations. 5 to 7 inches 
   expected across southwest facing mountains and ridges. Heavy 
   rain combined with saturated soil and melting snow across the 
   mountains will contribute toward possible flooding. 


* Low lying areas, creeks, streams, culverts, and portions of
  urban areas may experience flooding due to heavy rainfall.  

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.

&&
 


$$
JJW

The office that day

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

IssuedProductOfficeCountiesLasted
Jan 29, 6:09 PM PSTWind AdvisoryEKADel Norte, Humboldt, Lake, Mendocino, Trinity70 hr
Jan 30, 5:32 AM PSTWinter Storm WarningEKA66 hr

Nearby

Flood Watches in California, 2021Every flood watch in 2021

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.