Alert archive / Washington / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 21, NWS Spokane, WA

July 28, 2009Ferry County, Lincoln County, Stevens County, Washington

NWS Spokane, WA issued this severe thunderstorm warning at Jul 28, 2009, 5:08 PM PDT for Ferry County, Lincoln County, Stevens County, Washington. It was in force for 52 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 28, 2009, 5:08 PM PDT (00:08 UTC)
Expired
Jul 28, 2009, 6:00 PM PDT
In force
52 min
Issued by
NWS Spokane, WA
Area
Storm-based polygon

Counties Ferry County, WA, Lincoln County, WA, Stevens County, WA

The radar

The Spokane radar (KOTX), 55 km from the middle of the area, began a volume at 00:11 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

Spokane, WA (KOTX), launched 00:00Z, 0.1 hours before the alert went out and 142 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, Spokane, WA at 00:00Z on 2009-07-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 215 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, Spokane, WA at 00:00Z on 2009-07-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 18 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
215 J/kg
Mixed-layer CIN
-55 J/kg
Mixed-layer LCL
2530 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
18 m²/s²
0-3 km storm-relative helicity
77 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.4

Open this sounding in Storm Lab

The text

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

000 
WUUS56 KOTX 290008
SVROTX
WAC019-043-065-290100-
/O.NEW.KOTX.SV.W.0021.090729T0008Z-090729T0100Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SPOKANE WA
508 PM PDT TUE JUL 28 2009

THE NATIONAL WEATHER SERVICE IN SPOKANE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTH CENTRAL LINCOLN COUNTY IN EAST CENTRAL WASHINGTON...
  SOUTH CENTRAL FERRY COUNTY IN NORTHEAST WASHINGTON...
  SOUTHWESTERN STEVENS COUNTY IN NORTHEAST WASHINGTON...

* UNTIL 600 PM PDT

* AT 503 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED AN
  AREA OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER SIZE
  HAIL.  THESE STORMS WERE LOCATED NORTH OF MILES AND EAST OF
  KELLER AND WERE MOVING SOUTH AT 20 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO MILES
  AND LINCOLN

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF
YOUR HOME OR BUSINESS. THIS STORM HAS THE POTENTIAL TO CAUSE SERIOUS
INJURY AND SIGNIFICANT DAMAGE TO PROPERTY.

&&

LAT...LON 4776 11806 4770 11841 4812 11860 4818 11825
TIME...MOT...LOC 0007Z 343DEG 16KT 4806 11833 4804 11843

$$

RP
2 follow-up statements
000 
WWUS56 KOTX 290028
SVSOTX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SPOKANE WA
528 PM PDT TUE JUL 28 2009

WAC019-043-065-290100-
/O.CON.KOTX.SV.W.0021.000000T0000Z-090729T0100Z/
FERRY WA-STEVENS WA-LINCOLN WA-
528 PM PDT TUE JUL 28 2009

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 600 PM PDT
FOR NORTH CENTRAL LINCOLN...SOUTHWESTERN STEVENS AND SOUTH CENTRAL
FERRY COUNTIES...

AT 527 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE
HAIL.  THIS STORM WAS LOCATED 11 MILES NORTH OF MILES...OR 46 MILES
SOUTHEAST OF REPUBLIC...MOVING SOUTHEAST AT 20 MPH.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
LINCOLN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DOPPLER RADAR HAS INDICATED SOME WEAK ROTATION WITHIN THIS STORM.
WHILE NOT IMMEDIATELY LIKELY...A TORNADO MAY STILL DEVELOP. IF A
TORNADO IS SPOTTED...ACT QUICKLY AND MOVE TO A PLACE OF SAFETY IN A
STURDY STRUCTURE...SUCH AS A BASEMENT OR SMALL INTERIOR ROOM.

&&

LAT...LON 4776 11806 4770 11841 4812 11860 4818 11825
TIME...MOT...LOC 0028Z 334DEG 17KT 4806 11826

$$

RP
000 
WWUS56 KOTX 290052
SVSOTX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SPOKANE WA
552 PM PDT TUE JUL 28 2009

WAC019-043-065-290101-
/O.EXP.KOTX.SV.W.0021.000000T0000Z-090729T0100Z/
FERRY WA-STEVENS WA-LINCOLN WA-
552 PM PDT TUE JUL 28 2009

...THE SEVERE THUNDERSTORM WARNING FOR NORTH CENTRAL LINCOLN...
SOUTHWESTERN STEVENS AND SOUTH CENTRAL FERRY COUNTIES WILL EXPIRE AT
600 PM PDT...

THE STORM HAS MOVED EAST INTO SOUTHERN STEVENS COUNTY AND HAS 
WEAKEND IN INTENSITY AND...ALTHOUGH IT IS STILL PRODUCING 
HAIL THE SIZE OF PENNIES...IT IS NOT LONGER CONSIDERED SEVERE AND
THE WARNING HAS BEEN ALLOWED TO EXPIRE AND THE STORM IS NOW BEING
HIGHLIGHTED WITH A SIGNIFICANT WEATHER ADVISORY.



LAT...LON 4776 11806 4770 11841 4812 11860 4818 11825
TIME...MOT...LOC 0051Z 334DEG 17KT 4796 11819

$$

RP

The office that day

Everything else NWS Spokane, WA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 28, 5:49 PM PDTSpecial Weather StatementOTXLincoln41 min
Jul 28, 6:35 PM PDTFlash Flood WarningOTXChelan55 min
Jul 28, 7:29 PM PDTSevere Thunderstorm WarningOTXStevens46 min
Jul 28, 8:13 PM PDTSevere Thunderstorm WarningOTXFerry, Stevens47 min

Nearby

Severe Thunderstorm Warnings in Washington, 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.