Alert archive / Colorado / Tornado Warnings in 2013

Tornado Warning 7, NWS Denver/Boulder, CO

April 8, 2013Washington County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at Apr 8, 2013, 8:52 PM MDT for Washington County, Colorado. It was in force for 23 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
Apr 8, 2013, 8:52 PM MDT (02:52 UTC)
Expired
Apr 8, 2013, 9:15 PM MDT
In force
23 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon

County Washington County, CO

The radar

The Denver radar (KFTG), 118 km from the middle of the area, began a volume at 02:54 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 watch it was issued in

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

IssuedProductOfficeLasted
Apr 8, 2:16 PM MDTSevere Thunderstorm WatchSPC9 hr

The nearest sounding before it

Denver, CO (KDNR), launched 00:00Z, 2.9 hours before the alert went out and 40 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, Denver, CO at 00:00Z on 2013-04-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 105 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Denver, CO at 00:00Z on 2013-04-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 81 square meters per square second.1939587897Sfc1 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
105 J/kg
Mixed-layer CIN
-87 J/kg
Mixed-layer LCL
2884 m above ground
0-6 km bulk shear
56 kt
0-1 km storm-relative helicity
81 m²/s²
0-3 km storm-relative helicity
258 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

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

070 
WFUS55 KBOU 090252
TORBOU
COC121-090315-
/O.NEW.KBOU.TO.W.0007.130409T0252Z-130409T0315Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DENVER CO
852 PM MDT MON APR 8 2013

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

* TORNADO WARNING FOR...
  CENTRAL WASHINGTON COUNTY IN NORTHEAST COLORADO

* UNTIL 915 PM MDT

* AT 851 PM MDT...LOCAL LAW ENFORCEMENT OFFICIALS REPORTED A TORNADO
  6 MILES WEST OF AKRON. THIS STORM WAS MOVING NORTHEAST AT 25 MPH.
  ANOTHER STORM WITH A POSSIBLE TORNADO WAS LOCATED 8 MILES EAST OF
  WOODROW. DOWNED POWER LINES AND WIND GUSTS TO 65 MPH WERE REPORTED
  WITH THIS STORM.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO AKRON.

PEOPLE IN AKRON SHOULD TAKE COVER IN A STURDY BUILDING NOW!  

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR
OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 4038 10326 4031 10302 3994 10343 4012 10347
TIME...MOT...LOC 0251Z 213DEG 24KT 4016 10332

$$
1 follow-up statement
662 
WWUS55 KBOU 090306
SVSBOU

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
906 PM MDT MON APR 8 2013

COC121-090315-
/O.CON.KBOU.TO.W.0007.000000T0000Z-130409T0315Z/
WASHINGTON CO-
906 PM MDT MON APR 8 2013

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 915 PM MDT FOR NORTH
CENTRAL WASHINGTON COUNTY...

AT 905 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS STORM WAS
LOCATED 3 MILES EAST OF FREMONT BUTTE...OR 7 MILES NORTH OF AKRON. 
THIS STORM WAS MOVING NORTHEAST AT 30 MPH. ANOTHER SEVERE STORM
WAS LOCATED 5 MILES SOUTHWEST OF AKRON.

LOCATIONS REMAINING IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
AKRON.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR
OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 4006 10330 4018 10339 4038 10326 4032 10306
TIME...MOT...LOC 0305Z 210DEG 27KT 4026 10325

$$

The office that day

Everything else NWS Denver/Boulder, CO issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 8, 6:31 PM MDTSpecial Weather StatementBOUWashington44 min
Apr 8, 7:03 PM MDTSevere Thunderstorm WarningBOUMorgan, Washington27 min
Apr 8, 7:17 PM MDTTornado WarningBOUPhillips28 min
Apr 8, 7:24 PM MDTTornado WarningBOUWashington36 min
Apr 8, 7:34 PM MDTTornado WarningBOUMorgan, Washington26 min
Apr 8, 7:46 PM MDTSevere Thunderstorm WarningBOUPhillips29 min
Apr 8, 7:59 PM MDTTornado WarningBOUMorgan, Washington46 min
Apr 8, 8:06 PM MDTTornado WarningBOUWashington24 min
Apr 8, 8:20 PM MDTSevere Thunderstorm WarningBOUPhillips, Sedgwick40 min
Apr 8, 8:33 PM MDTTornado WarningBOUWashington27 min
Apr 8, 9:00 PM MDTTornado WarningBOULogan, Phillips30 min
Apr 8, 9:17 PM MDTTornado WarningBOUWashington28 min
Apr 8, 9:31 PM MDTTornado WarningBOUPhillips29 min
Apr 8, 9:45 PM MDTTornado WarningBOUWashington30 min
Apr 8, 10:01 PM MDTSevere Thunderstorm WarningBOUSedgwick29 min

Nearby

Tornado Warnings in Colorado, 2013Every tornado warning in 2013Tornadoes in 2013

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.