Alert archive / Colorado / Tornado Warnings in 2013

Tornado Warning 39, NWS Denver/Boulder, CO

July 31, 2013Arapahoe County, Elbert County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at Jul 31, 2013, 8:18 PM MDT for Arapahoe County, Elbert County, Colorado. It was in force for 27 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
Jul 31, 2013, 8:18 PM MDT (02:18 UTC)
Expired
Jul 31, 2013, 8:45 PM MDT
In force
27 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon
Tornado
Radar indicated
Hail
0.75 in

Counties Arapahoe County, CO, Elbert County, CO

The radar

The Denver radar (KFTG), 46 km from the middle of the area, began a volume at 02:19 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
Jul 31, 8:27 PM MDTTSTM WND GST 702 Sw Deer Trail, CO
Jul 31, 8:35 PM MDTTSTM WND GST 702 Ne Deer Trail, COPOWER OUTAGES.
Jul 31, 8:40 PM MDTTSTM WND DMGDeer Trail, CONUMEROUS POWER POLES SNAPPED IN HALF IN DEER TRAIL VICINITY. WIDEPREAD POWER OUTAGES IN CENTRAL ARAPAHOE COUNTY.

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

The nearest sounding before it

Denver, CO (KDEN), launched 00:00Z, 2.3 hours before the alert went out and 77 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 00:00Z on 2013-08-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 00:00Z on 2013-08-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -23 square meters per square second.19395878Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3666 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
-23 m²/s²
0-3 km storm-relative helicity
6 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

751 
WFUS55 KBOU 010218
TORBOU
COC005-039-010245-
/O.NEW.KBOU.TO.W.0039.130801T0218Z-130801T0245Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DENVER CO
818 PM MDT WED JUL 31 2013

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

* TORNADO WARNING FOR...
  EASTERN ARAPAHOE COUNTY IN NORTHEAST COLORADO...
  NORTH CENTRAL ELBERT COUNTY IN EAST CENTRAL COLORADO...

* UNTIL 845 PM MDT
    
* AT 817 PM MDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A
  TORNADO WAS LOCATED NEAR DEER TRAIL...OR 33 MILES NORTHWEST OF
  LIMON...MOVING SOUTHEAST AT 20 MPH.

  HAZARD...TORNADO. 

  SOURCE...RADAR INDICATED ROTATION. 

  IMPACT...MOBILE HOMES WILL BE DAMAGED OR DESTROYED. DAMAGE TO 
           ROOFS...WINDOWS AND VEHICLES WILL OCCUR. FLYING DEBRIS 
           WILL BE DEADLY TO PEOPLE AND ANIMALS. TREE DAMAGE IS 
           LIKELY. 

* LOCATIONS IMPACTED INCLUDE...
  DEER TRAIL.

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 IN A MOBILE HOME...A
VEHICLE OR OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND
PROTECT YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 3958 10418 3974 10410 3969 10389 3945 10398
TIME...MOT...LOC 0217Z 296DEG 17KT 3965 10408 

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

RPK
3 follow-up statements
949 
WWUS55 KBOU 010226
SVSBOU

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
826 PM MDT WED JUL 31 2013

COC005-039-010245-
/O.CON.KBOU.TO.W.0039.000000T0000Z-130801T0245Z/
ARAPAHOE CO-ELBERT CO-
826 PM MDT WED JUL 31 2013

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 845 PM MDT FOR EASTERN
ARAPAHOE AND NORTH CENTRAL ELBERT COUNTIES...
    
AT 826 PM MDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO 
WAS NEAR DEER TRAIL...OR 30 MILES NORTHWEST OF LIMON...MOVING 
SOUTHEAST AT 25 MPH.

HAZARD...TORNADO AND QUARTER SIZE HAIL. 

SOURCE...RADAR INDICATED ROTATION. 

IMPACT...MOBILE HOMES WILL BE DAMAGED OR DESTROYED. DAMAGE TO 
         ROOFS...WINDOWS AND VEHICLES WILL OCCUR. FLYING DEBRIS WILL 
         BE DEADLY TO PEOPLE AND ANIMALS. TREE DAMAGE IS LIKELY. 

LOCATIONS IMPACTED INCLUDE...
DEER TRAIL.

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 IN A MOBILE HOME...A
VEHICLE OR OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND
PROTECT YOURSELF FROM FLYING DEBRIS.

HEAVY RAINFALL MAY HIDE THIS TORNADO. DO NOT WAIT TO SEE OR HEAR THE
TORNADO. TAKE COVER NOW.

&&

LAT...LON 3958 10418 3974 10410 3969 10389 3945 10398
TIME...MOT...LOC 0226Z 295DEG 20KT 3962 10401 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

RPK
548 
WWUS55 KBOU 010234
SVSBOU

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
834 PM MDT WED JUL 31 2013

COC005-039-010245-
/O.CON.KBOU.TO.W.0039.000000T0000Z-130801T0245Z/
ARAPAHOE CO-ELBERT CO-
834 PM MDT WED JUL 31 2013

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 845 PM MDT FOR EASTERN
ARAPAHOE AND NORTH CENTRAL ELBERT COUNTIES...
    
AT 833 PM MDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO
WAS LOCATED 5 MILES SOUTHEAST OF DEER TRAIL...OR 25 MILES NORTHWEST
OF LIMON...MOVING SOUTHEAST AT 25 MPH.

HAZARD...TORNADO AND QUARTER SIZE HAIL. 

SOURCE...RADAR INDICATED ROTATION. 

IMPACT...MOBILE HOMES WILL BE DAMAGED OR DESTROYED. DAMAGE TO 
         ROOFS...WINDOWS AND VEHICLES WILL OCCUR. FLYING DEBRIS WILL 
         BE DEADLY TO PEOPLE AND ANIMALS. TREE DAMAGE IS LIKELY. 

LOCATIONS IMPACTED INCLUDE...
DEER TRAIL.

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 IN A MOBILE HOME...A
VEHICLE OR OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND
PROTECT YOURSELF FROM FLYING DEBRIS.

HEAVY RAINFALL MAY HIDE THIS TORNADO. DO NOT WAIT TO SEE OR HEAR THE
TORNADO. TAKE COVER NOW.

&&

LAT...LON 3958 10418 3974 10410 3969 10389 3945 10398
TIME...MOT...LOC 0233Z 308DEG 20KT 3957 10396 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

RPK
768 
WWUS55 KBOU 010243
SVSBOU

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
843 PM MDT WED JUL 31 2013

COC005-039-010252-
/O.EXP.KBOU.TO.W.0039.000000T0000Z-130801T0245Z/
ARAPAHOE CO-ELBERT CO-
843 PM MDT WED JUL 31 2013

...THE TORNADO WARNING FOR EASTERN ARAPAHOE AND NORTH CENTRAL ELBERT
COUNTIES WILL EXPIRE AT 845 PM MDT...
        
THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE AREA.
THEREFORE THE WARNING WILL BE ALLOWED TO EXPIRE.

LAT...LON 3958 10418 3974 10410 3969 10389 3945 10398
TIME...MOT...LOC 0238Z 296DEG 17KT 3957 10396 

$$

RPK

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 31, 7:00 PM MDTSpecial Weather StatementBOUAdams30 min
Jul 31, 7:11 PM MDTSevere Thunderstorm WarningBOUAdams34 min
Jul 31, 7:42 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe33 min
Jul 31, 8:07 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe23 min
Jul 31, 8:42 PM MDTSevere Thunderstorm WarningBOUArapahoe, Elbert33 min
Jul 31, 9:32 PM MDTSpecial Weather StatementBOULincoln28 min
Jul 31, 9:34 PM MDTSpecial Weather StatementBOUWashington26 min
Jul 31, 9:44 PM MDTSevere Thunderstorm WarningBOUWashington31 min
Aug 1, 3:40 PM MDTSevere Thunderstorm WarningBOUAdams, Weld50 min
Aug 1, 3:45 PM MDTSevere Thunderstorm WarningBOULincoln30 min
Aug 1, 4:02 PM MDTAreal Flood AdvisoryBOUElbert118 min
Aug 1, 4:11 PM MDTAreal Flood AdvisoryBOULincoln2 hr
Aug 1, 5:23 PM MDTSevere Thunderstorm WarningBOULogan, Weld52 min

Nearby

Tornado Warnings in Colorado, 2013Every tornado warning in 2013Tornadoes in 2013

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.