Alert archive / Colorado / Tornado Warnings in 2011

Tornado Warning 10, NWS Denver/Boulder, CO

May 30, 2011Weld County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at May 30, 2011, 2:20 PM MDT for Weld County, Colorado. It was in force for 25 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, 2:20 PM MDT (20:20 UTC)
Expired: May 30, 2011, 2:45 PM MDT
In force: 25 min
Issued by: NWS Denver/Boulder, CO
Area: Storm-based polygon

County Weld County, CO

The radar

The Denver radar (KFTG), 68 km from the middle of the area, began a volume at 20:23 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, 8.3 hours before the alert went out and 114 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: 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.

375 
WFUS55 KBOU 302020
TORBOU
COC123-302045-
/O.NEW.KBOU.TO.W.0010.110530T2020Z-110530T2045Z/

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

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

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

* UNTIL 245 PM MDT

* AT 220 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO NEAR HARDIN...OR
  17 MILES EAST OF GREELEY. THIS STORM WAS MOVING NORTHEAST AT 15
  MPH.

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

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 4050 10438 4044 10423 4022 10440 4028 10455
TIME...MOT...LOC 2020Z 211DEG 25KT 4034 10442

$$

2 follow-up statements

647 
WWUS55 KBOU 302026
SVSBOU

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

COC123-302045-
/O.CON.KBOU.TO.W.0010.000000T0000Z-110530T2045Z/
WELD CO-
226 PM MDT MON MAY 30 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 245 PM MDT FOR CENTRAL
WELD COUNTY...

AT 226 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS STORM WAS
LOCATED 4 MILES NORTHEAST OF HARDIN...OR 20 MILES EAST OF GREELEY.
THIS STORM WAS MOVING NORTHEAST AT 15 MPH.

THE SEVERE THUNDERSTORM WILL REMAIN OVER MAINLY RURAL AREAS OF THE
WARNED COUNTY.

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 4050 10438 4044 10423 4022 10440 4028 10455
TIME...MOT...LOC 2026Z 211DEG 25KT 4041 10435

$$

381 
WWUS55 KBOU 302042
SVSBOU

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

COC123-302052-
/O.EXP.KBOU.TO.W.0010.000000T0000Z-110530T2045Z/
WELD CO-
242 PM MDT MON MAY 30 2011

...THE TORNADO WARNING FOR CENTRAL WELD COUNTY WILL EXPIRE AT 245 PM
MDT...

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

LAT...LON 4050 10438 4044 10423 4022 10440 4028 10455
TIME...MOT...LOC 2042Z 211DEG 25KT 4051 10427

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
May 29, 9:42 PM MDT	Areal Flood Advisory	BOU	Grand	4 days
May 30, 1:12 PM MDT	Severe Thunderstorm Warning	BOU	Weld	20 min
May 30, 2:02 PM MDT	Severe Thunderstorm Warning	BOU	Weld	28 min
May 30, 2:24 PM MDT	Tornado Warning	BOU	Weld	36 min
May 30, 2:32 PM MDT	Severe Thunderstorm Warning	BOU	Adams	28 min
May 30, 2:49 PM MDT	Tornado Warning	BOU	Adams	26 min
May 30, 3:00 PM MDT	Tornado Warning	BOU	Adams, Morgan, Weld	30 min
May 30, 3:34 PM MDT	Special Weather Statement	BOU	Morgan	41 min
May 30, 3:35 PM MDT	Special Weather Statement	BOU	Logan	40 min
May 30, 3:53 PM MDT	Tornado Warning	BOU	Washington	22 min
May 30, 3:59 PM MDT	Special Weather Statement	BOU	Logan	46 min
May 30, 4:32 PM MDT	Special Weather Statement	BOU	Phillips, Sedgwick	28 min
May 30, 5:00 PM MDT	Special Weather Statement	BOU	Phillips, Sedgwick	30 min
May 30, 5:04 PM MDT	Severe Thunderstorm Warning	BOU	Sedgwick	22 min

Nearby

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