Alert archive / California / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 1, NWS Eureka, CA

May 28, 2009Trinity County, California

NWS Eureka, CA issued this severe thunderstorm warning at May 28, 2009, 3:38 PM PDT for Trinity County, California. It was in force for 37 min. 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
May 28, 2009, 3:38 PM PDT (22:38 UTC)
Expired
May 28, 2009, 4:15 PM PDT
In force
37 min
Issued by
NWS Eureka, CA
Area
Storm-based polygon

County Trinity County, CA

The radar

The Eureka (Bunker Hill) radar (KBHX), 85 km from the middle of the area, began a volume at 22:38 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
May 28, 4:00 PM PDTHAIL 0.759 E Hyampom, CA3/4 INCH HAIL REPORTED AT YOUTH CAMP 9 MI EAST OF HAYFORK.

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 12:00Z, 10.6 hours before the alert went out and 193 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 2009-05-28Temperature 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 2009-05-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -19 square meters per square second.1939Sfc1 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
1770 m above ground
0-6 km bulk shear
12 kt
0-1 km storm-relative helicity
-19 m²/s²
0-3 km storm-relative helicity
90 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.

000 
WUUS56 KEKA 282238
SVREKA
CAC105-282315-
/O.NEW.KEKA.SV.W.0001.090528T2238Z-090528T2315Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE EUREKA CA
338 PM PDT THU MAY 28 2009

THE NATIONAL WEATHER SERVICE IN EUREKA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL TRINITY COUNTY IN NORTHWEST CALIFORNIA...

* UNTIL 415 PM PDT

* AT 337 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING NICKEL SIZE HAIL.  THIS
  STORM WAS LOCATED 8 MILES SOUTHWEST OF BIG BAR...OR 22 MILES WEST
  OF WEAVERVILLE...AND MOVING NORTH AT 10 MPH.

* THE SEVERE THUNDERSTORM WILL OTHERWISE REMAIN OVER MAINLY RURAL
  AREAS OF THE INDICATED COUNTY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...DESTRUCTIVE HAIL...AND DEADLY CLOUD
TO GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

&&

LAT...LON 4078 12338 4070 12314 4053 12327 4058 12341
TIME...MOT...LOC 2238Z 198DEG 7KT 4062 12332

$$

MAB/BK
2 follow-up statements
000 
WWUS56 KEKA 282259
SVSEKA

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE EUREKA CA
359 PM PDT THU MAY 28 2009

CAC105-282315-
/O.CON.KEKA.SV.W.0001.000000T0000Z-090528T2315Z/
TRINITY CA-
359 PM PDT THU MAY 28 2009

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 415 PM PDT
FOR CENTRAL TRINITY COUNTY...

AT 350 PM PDT...THE PUBLIC REPORTED DIME SIZE HAIL WITH THIS 
THUNDERSTORM.  THIS STORM WAS LOCATED 6 MILES SOUTHWEST OF BIG 
BAR...OR 20 MILES WEST OF WEAVERVILLE...MOVING NORTH AT 10 MPH.

THE SEVERE THUNDERSTORM WILL OTHERWISE REMAIN OVER MAINLY RURAL AREAS
OF THE INDICATED COUNTY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...DESTRUCTIVE HAIL...AND DEADLY CLOUD
TO GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

&&

LAT...LON 4078 12338 4070 12314 4053 12327 4058 12341
TIME...MOT...LOC 2258Z 198DEG 7KT 4066 12330

$$

MB/BK
000 
WWUS56 KEKA 282315
SVSEKA

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE EUREKA CA
415 PM PDT THU MAY 28 2009

CAC105-282322-
/O.CAN.KEKA.SV.W.0001.000000T0000Z-090528T2315Z/
TRINITY CA-
415 PM PDT THU MAY 28 2009

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL TRINITY COUNTY IS
CANCELLED...

AT 415 PM...DOPPLER RADAR INDICATED THE THUNDERSTORM 3 MILES EAST OF 
HYAMPOM WHICH PROMPTED THE WARNING HAD WEAKENED. HOWEVER HEAVY RAIN 
AND SMALL HAIL IS STILL POSSIBLE WITH THIS STORM.

LAT...LON 4078 12338 4070 12314 4053 12327 4058 12341
TIME...MOT...LOC 2312Z 198DEG 7KT 4068 12329

$$

BK/MB

The office that day

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

IssuedProductOfficeCountiesLasted
May 28, 4:30 PM PDTSevere Thunderstorm WarningEKATrinity30 min

Nearby

Severe Thunderstorm Warnings in California, 2009Every severe thunderstorm warning in 2009

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.