Alert archive / Washington / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 46, NWS Spokane, WA

July 20, 2012Douglas County, Okanogan County, Washington

NWS Spokane, WA issued this severe thunderstorm warning at Jul 20, 2012, 3:27 PM PDT for Douglas County, Okanogan County, Washington. It was in force for 34 min. 4 reports 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: Jul 20, 2012, 3:27 PM PDT (22:27 UTC)
Expired: Jul 20, 2012, 4:01 PM PDT
In force: 34 min
Issued by: NWS Spokane, WA
Area: Storm-based polygon

Counties Douglas County, WA, Okanogan County, WA

The radar

The Spokane radar (KOTX), 122 km from the middle of the area, began a volume at 22:29 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

Time	Report	Where	Remark
Jul 20, 3:30 PM PDT	TSTM WND DMG	5 Ese Disautel, WA	ONE LARGE TREE AND SOME SMALLER TREES BLOWN DOWN ONTO HIGHWAY 155. ALSO SOME MUD AND DEBRIS WASHED ONTO THE ROAD.
Jul 20, 3:30 PM PDT	TSTM WND DMG	Nespelem, WA	NESPELEM SCHOOL HAD TREES 10 TO 12 INCHES FALL AND DAMAGE TO A DUMPSTER DUE TO HIGH WINDS.
Jul 20, 3:40 PM PDT	TSTM WND DMG	Nespelem, WA	POST OFFICE BUILDING SUSTAINED ROOF DAMAGE. RAIN ENTERED OFFICE LOBBY AND RESULTED IN MINOR WATER DAMAGE. DIME SIZE ALSO REPORTED WITH STORM.
Jul 20, 3:57 PM PDT	TSTM WND GST 54	2 S Nespelem, WA	NESPELEM RAWS

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Jul 20, 11:38 AM PDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Spokane, WA (KOTX), launched 12:00Z, 10.5 hours before the alert went out and 207 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 2619 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: -1 m²/s²
0-3 km storm-relative helicity: 66 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.

990 
WUUS56 KOTX 202227
SVROTX
WAC017-047-202330-
/O.NEW.KOTX.SV.W.0046.120720T2227Z-120720T2330Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SPOKANE WA
327 PM PDT FRI JUL 20 2012

THE NATIONAL WEATHER SERVICE IN SPOKANE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHEASTERN DOUGLAS COUNTY IN NORTH CENTRAL WASHINGTON...
  SOUTHEASTERN OKANOGAN COUNTY IN NORTH CENTRAL WASHINGTON...

* UNTIL 430 PM PDT

* AT 325 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS
  STORM WAS LOCATED 7 MILES NORTHWEST OF ELMER CITY...OR 32 MILES
  SOUTHEAST OF OMAK...AND MOVING NORTH AT 35 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  NESPELEM AND DISAUTEL

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS STORM WILL ALSO PRODUCE EXTREMELY HEAVY RAINFALL. IF DRIVING
THROUGH THE STORM REDUCE YOUR SPEED TO LOWER THE RISK OF
HYDROPLANING. ALSO BE PREPARED FOR PONDING OF WATER IN LOW LYING
AREAS.

&&

LAT...LON 4855 11901 4797 11891 4796 11898 4796 11910
      4795 11911 4794 11923 4856 11938
TIME...MOT...LOC 2226Z 166DEG 29KT 4808 11907

$$

RFOX.RFOX

1 follow-up statement

139 
WWUS56 KOTX 202301
SVSOTX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SPOKANE WA
401 PM PDT FRI JUL 20 2012

WAC017-047-202311-
/O.CAN.KOTX.SV.W.0046.000000T0000Z-120720T2330Z/
OKANOGAN WA-DOUGLAS WA-
401 PM PDT FRI JUL 20 2012

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN DOUGLAS AND
SOUTHEASTERN OKANOGAN COUNTIES IS CANCELLED...

DOPPLER RADAR INDICATED THE STORM WAS NO LONGER SEVERE AND THE
WARNING WAS ALLOWED TO EXPIRE. EXPECT HEAVY RAIN...WIND GUSTS TO 30 MPH
AND OCCASIONAL LIGHTNING WITH THIS STORM. 

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 800 PM PDT FRIDAY
EVENING FOR CENTRAL IDAHO AND NORTHEASTERN WASHINGTON.

LAT...LON 4855 11901 4797 11891 4796 11898 4796 11910
      4795 11911 4794 11923 4856 11938
TIME...MOT...LOC 2301Z 166DEG 29KT 4835 11917

$$

RFOX.RFOX

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 20, 12:26 AM PDT	Special Weather Statement	OTX	Okanogan	49 min
Jul 20, 1:09 AM PDT	Special Weather Statement	OTX	Okanogan	51 min
Jul 20, 1:10 AM PDT	Areal Flood Advisory	OTX	Okanogan	4 hr
Jul 20, 11:34 AM PDT	Special Weather Statement	OTX		56 min
Jul 20, 12:17 PM PDT	Flash Flood Warning	OTX	Asotin	28 min
Jul 20, 12:19 PM PDT	Special Weather Statement	OTX	Asotin	41 min
Jul 20, 12:39 PM PDT	Severe Thunderstorm Warning	OTX	Asotin	51 min
Jul 20, 12:59 PM PDT	Severe Thunderstorm Warning	OTX	Grant	46 min
Jul 20, 1:04 PM PDT	Areal Flood Advisory	OTX	Asotin	4 hr
Jul 20, 1:15 PM PDT	Flash Flood Warning	OTX	Grant	60 min
Jul 20, 1:15 PM PDT	Severe Thunderstorm Warning	OTX	Grant	60 min
Jul 20, 1:46 PM PDT	Severe Thunderstorm Warning	OTX	Douglas, Grant	44 min
Jul 20, 2:08 PM PDT	Areal Flood Advisory	OTX	Grant	3 hr
Jul 20, 2:22 PM PDT	Flash Flood Warning	OTX	Okanogan	83 min
Jul 20, 2:29 PM PDT	Severe Thunderstorm Warning	OTX	Garfield, Whitman	46 min
Jul 20, 2:33 PM PDT	Special Weather Statement	OTX	Okanogan	57 min
Jul 20, 2:34 PM PDT	Flash Flood Warning	OTX	Okanogan	86 min
Jul 20, 2:47 PM PDT	Severe Thunderstorm Warning	OTX	Okanogan	58 min
Jul 20, 3:17 PM PDT	Severe Thunderstorm Warning	OTX	Ferry, Grant, Lincoln, Okanogan, Spokane, Stevens	43 min
Jul 20, 3:18 PM PDT	Areal Flood Advisory	OTX	Whitman	117 min
Jul 20, 3:20 PM PDT	Severe Thunderstorm Warning	OTX	Lincoln, Spokane, Whitman	40 min
Jul 20, 3:35 PM PDT	Areal Flood Warning	OTX	Pend Oreille	4 hr
Jul 20, 3:37 PM PDT	Severe Thunderstorm Warning	OTX	Pend Oreille	53 min
Jul 20, 3:47 PM PDT	Flash Flood Warning	OTX	Ferry, Okanogan	88 min
Jul 20, 4:22 PM PDT	Special Weather Statement	OTX	Ferry	38 min
Jul 20, 4:30 PM PDT	Severe Thunderstorm Warning	OTX	Ferry, Okanogan	30 min

Nearby

Severe Thunderstorm Warnings in Washington, 2012 Every severe thunderstorm warning in 2012

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.