Alert archive / Colorado / Tornado Warnings in 2011
Tornado Warning 5, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this tornado warning at May 17, 2011, 6:26 PM MDT for Washington County, Colorado. It was in force for 34 min. 2 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 17, 2011, 6:26 PM MDT (00:26 UTC)
- Expired
- May 17, 2011, 7:00 PM MDT
- In force
- 34 min
- Issued by
- NWS Denver/Boulder, CO
- Area
- Storm-based polygon
County Washington County, CO
The radar
The Denver radar (KFTG), 120 km from the middle of the area, began a volume at 00:29 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, 6:34 PM MDT | TORNADO | 5 Ne Anton, CO | ON THE GROUND FOR ABOUT 5 MINUTES |
| 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, 0.4 hours before the alert went out and 11 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.
741 WFUS55 KBOU 180026 TORBOU COC121-180100- /O.NEW.KBOU.TO.W.0005.110518T0026Z-110518T0100Z/ BULLETIN - EAS ACTIVATION REQUESTED TORNADO WARNING NATIONAL WEATHER SERVICE DENVER CO 626 PM MDT TUE MAY 17 2011 THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A * TORNADO WARNING FOR... CENTRAL WASHINGTON COUNTY IN NORTHEAST COLORADO * UNTIL 700 PM MDT * AT 618 PM MDT...TRAINED WEATHER SPOTTERS REPORTED A TORNADO 4 MILES SOUTH OF ANTON. THIS STORM WAS MOVING NORTH AT 20 MPH. * LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO ELBA. 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 4008 10327 4006 10293 3974 10306 3978 10325 TIME...MOT...LOC 0026Z 189DEG 18KT 3977 10316 $$
4 follow-up statements
510 WWUS55 KBOU 180031 SVSBOU SEVERE WEATHER STATEMENT NATIONAL WEATHER SERVICE DENVER CO 631 PM MDT TUE MAY 17 2011 COC121-180100- /O.CON.KBOU.TO.W.0005.000000T0000Z-110518T0100Z/ WASHINGTON CO- 631 PM MDT TUE MAY 17 2011 ...A TORNADO WARNING REMAINS IN EFFECT UNTIL 700 PM MDT FOR CENTRAL WASHINGTON COUNTY... AT 632 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A TORNADO. THIS STORM WAS LOCATED 9 MILES SOUTH OF ELBA...OR 26 MILES SOUTH OF AKRON. THIS STORM WAS MOVING NORTH AT 20 MPH. LOCATIONS REMAINING IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO ELBA. PRECAUTIONARY/PREPAREDNESS ACTIONS... TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT YOURSELF FROM FLYING DEBRIS. && LAT...LON 4008 10327 4006 10293 3974 10306 3978 10325 TIME...MOT...LOC 0032Z 189DEG 18KT 3980 10315 $$
334 WWUS55 KBOU 180044 SVSBOU SEVERE WEATHER STATEMENT NATIONAL WEATHER SERVICE DENVER CO 644 PM MDT TUE MAY 17 2011 COC121-180100- /O.CON.KBOU.TO.W.0005.000000T0000Z-110518T0100Z/ WASHINGTON CO- 644 PM MDT TUE MAY 17 2011 ...A TORNADO WARNING REMAINS IN EFFECT UNTIL 700 PM MDT FOR CENTRAL WASHINGTON COUNTY... AT 634 PM MDT...TRAINED WEATHER SPOTTERS REPORTED A TORNADO. RADAR CONTINUES TO INDICATE ROTATION WITH THIS STORM. THIS STORM WAS LOCATED 3 MILES SOUTHEAST OF ELBA...OR 22 MILES SOUTH OF AKRON. THIS STORM WAS MOVING NORTH AT 20 MPH. LOCATIONS REMAINING IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO ELBA. 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 4008 10327 4006 10293 3974 10306 3978 10325 TIME...MOT...LOC 0044Z 189DEG 18KT 3986 10314 $$
379 WWUS55 KBOU 180052 SVSBOU SEVERE WEATHER STATEMENT NATIONAL WEATHER SERVICE DENVER CO 652 PM MDT TUE MAY 17 2011 COC121-180100- /O.CON.KBOU.TO.W.0005.000000T0000Z-110518T0100Z/ WASHINGTON CO- 652 PM MDT TUE MAY 17 2011 ...A TORNADO WARNING REMAINS IN EFFECT UNTIL 700 PM MDT FOR CENTRAL WASHINGTON COUNTY... AT 652 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS STORM WAS LOCATED OVER CENTRAL WASHINGTON COUNTY...OR 22 MILES SOUTHEAST OF AKRON. THIS STORM WAS MOVING NORTHEAST AT 25 MPH. THE SEVERE THUNDERSTORM WILL REMAIN OVER MAINLY RURAL AREAS OF THE WARNED COUNTY. PRECAUTIONARY/PREPAREDNESS ACTIONS... TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT YOURSELF FROM FLYING DEBRIS. && LAT...LON 3980 10313 4003 10314 3998 10296 3974 10306 TIME...MOT...LOC 0052Z 227DEG 21KT 3989 10302 $$
016 WWUS55 KBOU 180101 SVSBOU SEVERE WEATHER STATEMENT NATIONAL WEATHER SERVICE DENVER CO 701 PM MDT TUE MAY 17 2011 COC121-180110- /O.EXP.KBOU.TO.W.0005.000000T0000Z-110518T0100Z/ WASHINGTON CO- 701 PM MDT TUE MAY 17 2011 ...THE TORNADO WARNING FOR CENTRAL WASHINGTON COUNTY HAS EXPIRED... A NEW TORNADO WARNING WARNING HAS BEEN ISSUED FOR EAST CENTRAL WASHINGTON COUNTY. LAT...LON 3980 10313 4003 10314 3998 10296 3974 10306 TIME...MOT...LOC 0052Z 227DEG 21KT 3989 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, 6:32 PM MDT | Severe Thunderstorm Warning | BOU | Logan, Washington | 43 min |
| May 17, 6:59 PM MDT | Tornado Warning | BOU | Washington | 31 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.