Alert archive / Colorado / Tornado Warnings in 2015

Tornado Warning 56, NWS Denver/Boulder, CO

August 17, 2015Douglas County, Elbert County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at Aug 17, 2015, 3:17 PM MDT for Douglas County, Elbert County, Colorado. It was in force for 28 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
Aug 17, 2015, 3:17 PM MDT (21:17 UTC)
Expired
Aug 17, 2015, 3:45 PM MDT
In force
28 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon
Tornado
Radar indicated
Hail
1.5 in

Counties Douglas County, CO, Elbert County, CO

The radar

The Denver radar (KFTG), 66 km from the middle of the area, began a volume at 21:20 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
Aug 17, 3:17 PM MDTTORNADO5 Sw Kiowa, COWEAK TORNADO ON GROUND FOR 5 MINUTES IN OPEN FIELD. NO DAMAGE REPORTED.

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

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 17, 2:32 PM MDTTornado WatchSPC7 hr

The nearest sounding before it

Denver, CO (KDEN), launched 12:00Z, 9.3 hours before the alert went out and 137 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 2015-08-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 318 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 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 2015-08-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -36 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
318 J/kg
Mixed-layer CIN
-267 J/kg
Mixed-layer LCL
1605 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
-36 m²/s²
0-3 km storm-relative helicity
5 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.

774 
WFUS55 KBOU 172117
TORBOU
COC035-039-172145-
/O.NEW.KBOU.TO.W.0056.150817T2117Z-150817T2145Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DENVER CO
317 PM MDT MON AUG 17 2015

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

* TORNADO WARNING FOR...
  WEST CENTRAL ELBERT COUNTY IN EAST CENTRAL COLORADO...
  SOUTHEASTERN DOUGLAS COUNTY IN NORTHEASTERN COLORADO...

* UNTIL 345 PM MDT
    
* AT 316 PM MDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A
  TORNADO WAS LOCATED 5 MILES NORTHWEST OF ELBERT...OR 31 MILES NORTH
  OF COLORADO SPRINGS...MOVING EAST AT 20 MPH.

  HAZARD...TORNADO AND PING PONG BALL SIZE HAIL. 

  SOURCE...RADAR INDICATED ROTATION. 

  IMPACT...FLYING DEBRIS WILL BE DANGEROUS TO THOSE CAUGHT WITHOUT 
           SHELTER. MOBILE HOMES WILL BE DAMAGED OR DESTROYED. 
           DAMAGE TO ROOFS...WINDOWS AND VEHICLES WILL OCCUR.  TREE 
           DAMAGE IS LIKELY. 

* LOCATIONS IMPACTED INCLUDE...
  ELBERT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! MOVE TO A BASEMENT OR AN INTERIOR ROOM ON THE LOWEST
FLOOR OF A STURDY BUILDING. AVOID WINDOWS. IF YOU ARE IN A MOBILE
HOME...A VEHICLE OR OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL
SHELTER AND PROTECT YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 3913 10479 3935 10466 3921 10424 3913 10433
TIME...MOT...LOC 2116Z 287DEG 18KT 3926 10463 

TORNADO...RADAR INDICATED
HAIL...1.50IN

$$

COOPER

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 16, 7:04 PM MDTAreal Flood AdvisoryBOUElbert116 min
Aug 16, 8:18 PM MDTAreal Flood AdvisoryBOULincoln3 hr
Aug 16, 8:23 PM MDTSpecial Weather StatementBOULincoln37 min
Aug 17, 2:32 PM MDTSevere Thunderstorm WarningBOUClear Creek, Jefferson16 min
Aug 17, 3:07 PM MDTSevere Thunderstorm WarningBOUDouglas, Jefferson38 min
Aug 17, 3:18 PM MDTTornado WarningBOUDouglas, Jefferson27 min
Aug 17, 3:34 PM MDTSevere Thunderstorm WarningBOUDouglas, Elbert26 min
Aug 17, 3:43 PM MDTSevere Thunderstorm WarningBOUMorgan, Weld47 min
Aug 17, 3:43 PM MDTTornado Warning Tornado observedBOUDouglas32 min
Aug 17, 3:47 PM MDTSevere Thunderstorm WarningBOUArapahoe, Elbert, Lincoln, Washington43 min
Aug 17, 3:51 PM MDTSevere Thunderstorm WarningBOUElbert39 min
Aug 17, 3:56 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe, Elbert49 min
Aug 17, 4:05 PM MDTSevere Thunderstorm WarningBOUElbert40 min
Aug 17, 4:21 PM MDTSevere Thunderstorm WarningBOUWashington24 min
Aug 17, 4:28 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe, Elbert, Lincoln, Logan, Morgan and 1 more47 min
Aug 17, 4:33 PM MDTFlash Flood WarningBOUElbert, Lincoln3 hr
Aug 17, 4:38 PM MDTTornado WarningBOULincoln37 min
Aug 17, 5:07 PM MDTSevere Thunderstorm WarningBOUElbert, Lincoln, Morgan, Washington38 min
Aug 17, 5:42 PM MDTSevere Thunderstorm WarningBOULincoln48 min

Nearby

Tornado Warnings in Colorado, 2015Every tornado warning in 2015Tornadoes in 2015

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.