Alert archive / Colorado / Tornado Warnings in 2011

Tornado Warning 12, NWS Denver/Boulder, CO

May 30, 2011Adams County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at May 30, 2011, 2:49 PM MDT for Adams County, Colorado. It was in force for 26 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
May 30, 2011, 2:49 PM MDT (20:49 UTC)
Expired
May 30, 2011, 3:15 PM MDT
In force
26 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon

County Adams County, CO

The radar

The Denver radar (KFTG), 17 km from the middle of the area, began a volume at 20:51 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

Denver, CO (KDNR), launched 12:00Z, 8.8 hours before the alert went out and 96 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 12:00Z on 2011-05-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 19 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 12:00Z on 2011-05-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 64 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
19 J/kg
Mixed-layer CIN
-134 J/kg
Mixed-layer LCL
1603 m above ground
0-6 km bulk shear
75 kt
0-1 km storm-relative helicity
64 m²/s²
0-3 km storm-relative helicity
104 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.

844 
WFUS55 KBOU 302049
TORBOU
COC001-302115-
/O.NEW.KBOU.TO.W.0012.110530T2049Z-110530T2115Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DENVER CO
249 PM MDT MON MAY 30 2011

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

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

* UNTIL 315 PM MDT

* AT 249 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO 2 MILES NORTH OF
  BENNETT...OR 29 MILES EAST OF DENVER. THIS STORM WAS MOVING
  NORTHEAST AT 15 MPH.

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

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 3991 10428 3975 10430 3974 10446 3991 10446
TIME...MOT...LOC 2049Z 228DEG 26KT 3980 10439

$$
2 follow-up statements
299 
WWUS55 KBOU 302055
SVSBOU

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
255 PM MDT MON MAY 30 2011

COC001-302115-
/O.CON.KBOU.TO.W.0012.000000T0000Z-110530T2115Z/
ADAMS CO-
255 PM MDT MON MAY 30 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 315 PM MDT FOR CENTRAL
ADAMS COUNTY...

AT 256 PM MDT...THE PUBLIC REPORTED A FUNNEL CLOUD.  THIS STORM WAS
LOCATED 5 MILES NORTHEAST OF BENNETT...OR 32 MILES EAST OF DENVER.
THIS STORM WAS MOVING NORTHEAST AT 15 MPH.

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

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 3991 10428 3975 10430 3974 10446 3991 10446
TIME...MOT...LOC 2056Z 228DEG 26KT 3983 10434

$$
199 
WWUS55 KBOU 302111
SVSBOU

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
311 PM MDT MON MAY 30 2011

COC001-302121-
/O.EXP.KBOU.TO.W.0012.000000T0000Z-110530T2115Z/
ADAMS CO-
311 PM MDT MON MAY 30 2011

...THE TORNADO WARNING FOR CENTRAL ADAMS COUNTY WILL EXPIRE AT 315 PM
MDT...

THE THUNDERSTORM THAT PROMPTED THE WARNING HAS WEAKENED AND IS NO
LONGER EXPECTED TO PRODUCE SEVERE WEATHER.

LAT...LON 3991 10428 3975 10430 3974 10446 3991 10446
TIME...MOT...LOC 2111Z 228DEG 26KT 3990 10423

$$

The office that day

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

IssuedProductOfficeCountiesLasted
May 29, 9:42 PM MDTAreal Flood AdvisoryBOUGrand4 days
May 30, 1:12 PM MDTSevere Thunderstorm WarningBOUWeld20 min
May 30, 2:02 PM MDTSevere Thunderstorm WarningBOUWeld28 min
May 30, 2:20 PM MDTTornado WarningBOUWeld25 min
May 30, 2:24 PM MDTTornado WarningBOUWeld36 min
May 30, 2:32 PM MDTSevere Thunderstorm WarningBOUAdams28 min
May 30, 3:00 PM MDTTornado WarningBOUAdams, Morgan, Weld30 min
May 30, 3:34 PM MDTSpecial Weather StatementBOUMorgan41 min
May 30, 3:35 PM MDTSpecial Weather StatementBOULogan40 min
May 30, 3:53 PM MDTTornado WarningBOUWashington22 min
May 30, 3:59 PM MDTSpecial Weather StatementBOULogan46 min
May 30, 4:32 PM MDTSpecial Weather StatementBOUPhillips, Sedgwick28 min
May 30, 5:00 PM MDTSpecial Weather StatementBOUPhillips, Sedgwick30 min
May 30, 5:04 PM MDTSevere Thunderstorm WarningBOUSedgwick22 min

Nearby

Tornado Warnings in Colorado, 2011Every tornado warning in 2011Tornadoes in 2011

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.