Alert archive / Colorado / Tornado Warnings in 2011

Tornado Warning 13, NWS Denver/Boulder, CO

May 30, 2011Adams County, Morgan County, Weld County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at May 30, 2011, 3:00 PM MDT for Adams County, Morgan County, Weld County, Colorado. It was in force for 30 min. 3 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
May 30, 2011, 3:00 PM MDT (21:00 UTC)
Expired
May 30, 2011, 3:30 PM MDT
In force
30 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon

Counties Adams County, CO, Morgan County, CO, Weld County, CO

The radar

The Denver radar (KFTG), 51 km from the middle of the area, began a volume at 21:00 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 30, 3:15 PM MDTHAIL 0.7512 Se Roggen, CO
May 30, 3:18 PM MDTHAIL 0.7515 Se Roggen, CO
May 30, 3:22 PM MDTHAIL 0.7518 Se Roggen, CO

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

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 9.0 hours before the alert went out and 76 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°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.

213 
WFUS55 KBOU 302100
TORBOU
COC001-087-123-302130-
/O.NEW.KBOU.TO.W.0013.110530T2100Z-110530T2130Z/

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

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTHWESTERN MORGAN COUNTY IN NORTHEAST COLORADO
  NORTH CENTRAL ADAMS COUNTY IN NORTHEAST COLORADO
  SOUTH CENTRAL WELD COUNTY IN NORTHEAST COLORADO

* UNTIL 330 PM MDT

* AT 300 PM MDT...TRAINED WEATHER SPOTTERS REPORTED A TORNADO 9 MILES
  SOUTHWEST OF HOYT...OR 31 MILES SOUTHWEST OF FORT MORGAN. THIS
  STORM WAS MOVING NORTHEAST AT 20 MPH.

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

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 4020 10395 3997 10387 3992 10429 4009 10433
TIME...MOT...LOC 2100Z 231DEG 22KT 3998 10419

$$
3 follow-up statements
510 
WWUS55 KBOU 302104
SVSBOU

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

COC001-087-123-302130-
/O.CON.KBOU.TO.W.0013.000000T0000Z-110530T2130Z/
MORGAN CO-ADAMS CO-WELD CO-
304 PM MDT MON MAY 30 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 330 PM MDT FOR EXTREME
SOUTH CENTRAL WELD...NORTH CENTRAL ADAMS AND SOUTHWESTERN MORGAN
COUNTIES...

AT 304 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
TORNADO.  THIS STORM WAS LOCATED 8 MILES SOUTHWEST OF HOYT...OR 30
MILES SOUTHWEST OF FORT MORGAN. THIS STORM WAS MOVING NORTHEAST AT 20
MPH.

LOCATIONS REMAINING IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
HOYT AND ADENA.

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 4020 10395 3997 10387 3992 10429 4009 10433
TIME...MOT...LOC 2104Z 231DEG 22KT 3999 10417

$$
317 
WWUS55 KBOU 302112
SVSBOU

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

COC001-087-123-302130-
/O.CON.KBOU.TO.W.0013.000000T0000Z-110530T2130Z/
MORGAN CO-ADAMS CO-WELD CO-
312 PM MDT MON MAY 30 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 330 PM MDT FOR EXTREME
SOUTH CENTRAL WELD...NORTH CENTRAL ADAMS AND SOUTHWESTERN MORGAN
COUNTIES...

AT 312 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS STORM WAS
LOCATED 7 MILES WEST OF HOYT...OR 26 MILES SOUTHWEST OF FORT MORGAN.
THIS STORM WAS MOVING NORTHEAST AT 20 MPH.

LOCATIONS REMAINING IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
HOYT AND ADENA.

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 4020 10395 3997 10387 3992 10429 4009 10433
TIME...MOT...LOC 2112Z 201DEG 20KT 4005 10419

$$
969 
WWUS55 KBOU 302131
SVSBOU

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

COC001-087-123-302140-
/O.EXP.KBOU.TO.W.0013.000000T0000Z-110530T2130Z/
MORGAN CO-ADAMS CO-WELD CO-
331 PM MDT MON MAY 30 2011

...THE TORNADO WARNING FOR EXTREME SOUTH CENTRAL WELD...NORTH CENTRAL
ADAMS AND SOUTHWESTERN MORGAN COUNTIES HAS EXPIRED...

THE THUNDERSTORM THAT PROMPTED THE WARNING HAS WEAKENED...HOWEVER 
RESIDENTS OVER SOUTHWESTERN MORGAN COUNTY SHOULD BE PREPARED FOR 
WIND GUSTS TO 50 MPH...HAIL TO PENNY SIZE AND HEAVY RAIN UP TO ONE 
HALF INCH IN 30 MINUTES.

LAT...LON 4020 10395 3997 10387 3992 10429 4009 10433
TIME...MOT...LOC 2130Z 201DEG 20KT 4014 10414

$$

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, 2:49 PM MDTTornado WarningBOUAdams26 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.