Alert archive / Colorado / Tornado Warnings in 2011
Tornado Warning 6, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this tornado warning at May 17, 2011, 6:59 PM MDT for Washington County, Colorado. It was in force for 31 min. 1 report 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 17, 2011, 6:59 PM MDT (00:59 UTC)
- Expired
- May 17, 2011, 7:30 PM MDT
- In force
- 31 min
- Issued by
- NWS Denver/Boulder, CO
- Area
- Storm-based polygon
County Washington County, CO
The radar
The Goodland radar (KGLD), 129 km from the middle of the area, began a volume at 00:59 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 |
|---|---|---|---|
| May 17, 7:05 PM MDT | HAIL 1 | 8 E Elba, CO | BREIF HEAVY RAIN...0.52 INCH IN 10 MINUTES |
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 00:00Z, 1.0 hours before the alert went out and 32 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.
- Mixed-layer CAPE
- 26 J/kg
- Mixed-layer CIN
- -104 J/kg
- Mixed-layer LCL
- 1293 m above ground
- 0-6 km bulk shear
- 41 kt
- 0-1 km storm-relative helicity
- 22 m²/s²
- 0-3 km storm-relative helicity
- 146 m²/s²
- Significant tornado parameter
- -0.0
- Supercell composite
- -1.5
The text
As transmitted, in the capitals the NWS used until 2016.
240
WFUS55 KBOU 180059
TORBOU
COC121-180130-
/O.NEW.KBOU.TO.W.0006.110518T0059Z-110518T0130Z/
BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DENVER CO
659 PM MDT TUE MAY 17 2011
THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A
* TORNADO WARNING FOR...
EAST CENTRAL WASHINGTON COUNTY IN NORTHEAST COLORADO
* UNTIL 730 PM MDT
* AT 700 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO 16 MILES SOUTH
OF OTIS...OR 18 MILES SOUTHEAST OF AKRON. THIS STORM WAS MOVING
NORTHEAST AT 25 MPH.
* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO OTIS.
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 3988 10295 3989 10316 4018 10306 4017 10279
4016 10279 4009 10279
TIME...MOT...LOC 0100Z 221DEG 20KT 3995 10302
$$1 follow-up statement
958
WWUS55 KBOU 180130
SVSBOU
SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
730 PM MDT TUE MAY 17 2011
COC121-180140-
/O.EXP.KBOU.TO.W.0006.000000T0000Z-110518T0130Z/
WASHINGTON CO-
730 PM MDT TUE MAY 17 2011
...THE TORNADO WARNING FOR EAST CENTRAL WASHINGTON COUNTY HAS
EXPIRED...
THE THUNDERSTORM THAT PROMPTED THE WARNING HAS WEAKENED AND IS NO
LONGER EXPECTED TO PRODUCE A TORNADO.
LAT...LON 3988 10295 3989 10316 4018 10306 4017 10279
4016 10279 4009 10279
TIME...MOT...LOC 0059Z 221DEG 20KT 3995 10302
$$The office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 17, 6:11 PM MDT | Tornado Warning | BOU | Washington | 34 min |
| May 17, 6:13 PM MDT | Tornado Warning | BOU | Washington | 15 min |
| May 17, 6:26 PM MDT | Tornado Warning | BOU | Washington | 34 min |
| May 17, 6:32 PM MDT | Severe Thunderstorm Warning | BOU | Logan, Washington | 43 min |
| May 18, 4:10 AM MDT | Flash Flood Watch | BOU | Boulder, Larimer | 16 hr |
| May 18, 4:43 AM MDT | Winter Storm Warning | BOU | Boulder, Grand, Jackson, Larimer | 24 hr |
| May 18, 4:43 AM MDT | Winter Weather Advisory | BOU | Boulder, Clear Creek, Douglas, Gilpin, Grand, Jackson and 4 more | 24 hr |
| May 18, 1:13 PM MDT | Tornado Warning | BOU | Adams, Broomfield | 31 min |
| May 18, 2:16 PM MDT | Areal Flood Advisory | BOU | Adams, Broomfield | 119 min |
| May 18, 2:29 PM MDT | Tornado Warning | BOU | Adams | 14 min |
| May 18, 2:38 PM MDT | Severe Thunderstorm Warning | BOU | Adams, Broomfield, Weld | 19 min |
| May 18, 5:47 PM MDT | Severe Thunderstorm Warning | BOU | Lincoln | 58 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.