Alert archive / Colorado / Tornado Warnings in 2014

Tornado Warning 16, NWS Denver/Boulder, CO

May 20, 2014Arapahoe County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at May 20, 2014, 4:00 PM MDT for Arapahoe County, Colorado. It was in force for 30 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 20, 2014, 4:00 PM MDT (22:00 UTC)
Expired: May 20, 2014, 4:30 PM MDT
In force: 30 min
Issued by: NWS Denver/Boulder, CO
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 1.25 in

County Arapahoe County, CO

The radar

The Denver radar (KFTG), 20 km from the middle of the area, began a volume at 22:01 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 watch it was issued in

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

Issued	Product	Office	Lasted
May 20, 2:31 PM MDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Denver, CO (KDEN), launched 12:00Z, 10.0 hours before the alert went out and 126 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: 1 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1142 m above ground
0-6 km bulk shear: 53 kt
0-1 km storm-relative helicity: 12 m²/s²
0-3 km storm-relative helicity: 59 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.

892 
WFUS55 KBOU 202200
TORBOU
COC005-202230-
/O.NEW.KBOU.TO.W.0016.140520T2200Z-140520T2230Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DENVER CO
400 PM MDT TUE MAY 20 2014

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

* TORNADO WARNING FOR...
  WESTERN ARAPAHOE COUNTY IN NORTHEAST COLORADO...

* UNTIL 430 PM MDT

* AT 357 PM MDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A
  TORNADO WAS LOCATED OVER SOUTHWESTERN AURORA...OR 13 MILES EAST OF 
  DENVER...MOVING EAST AT 20 MPH. THIS THUNDERSTORM HAS A HISTORY OF 
  PRODUCING LARGE HAIL AS IT MOVED OVER SOUTHERN DENVER. SPOTTERS 
  WATCHING THIS STORM HAVE BEEN REPORTING A PERSISTENT WALL CLOUD 
  AND INTERMITTENT SHORT-LIVED FUNNEL CLOUDS. THIS TORNADO WARNING 
  REPLACES THE SEVERE THUNDERSTORM WARNING THAT WAS IN EFFECT UNTIL 
  4 PM MDT. 

  HAZARD...TORNADO AND HALF DOLLAR SIZE HAIL. 

  SOURCE...WEATHER SPOTTERS REPORTED FUNNEL CLOUD. 

  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...
  AURORA...NORTHEASTERN CENTENNIAL...ARAPAHOE PARK AND BUCKLEY AFB. 

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.

MOTORISTS SHOULD NOT TAKE SHELTER UNDER HIGHWAY OVERPASSES. IF YOU
CANNOT SAFELY DRIVE AWAY FROM THE TORNADO...AS A LAST RESORT...EITHER
PARK YOUR VEHICLE AND STAY PUT...OR ABANDON YOUR VEHICLE AND LIE DOWN
IN A LOW LYING AREA AND PROTECT YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 3958 10483 3973 10486 3974 10443 3957 10441
TIME...MOT...LOC 2157Z 273DEG 18KT 3968 10472 

TORNADO...RADAR INDICATED
HAIL...1.25IN

$$

DANKERS

1 follow-up statement

681 
WWUS55 KBOU 202230
SVSBOU

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
430 PM MDT TUE MAY 20 2014

COC005-202239-
/O.EXP.KBOU.TO.W.0016.000000T0000Z-140520T2230Z/
ARAPAHOE CO-
430 PM MDT TUE MAY 20 2014

...THE TORNADO WARNING FOR WESTERN ARAPAHOE COUNTY WILL EXPIRE AT 430
PM MDT...
                
THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER APPEARS CAPABLE OF PRODUCING A TORNADO.
THEREFORE THE WARNING WILL BE ALLOWED TO EXPIRE.  HOWEVER SMALL
HAIL....GUSTY WINDS AND HEAVY RAIN ARE STILL POSSIBLE WITH THIS
THUNDERSTORM.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM MDT
TUESDAY EVENING FOR NORTHEAST COLORADO.

LAT...LON 3958 10483 3973 10486 3974 10443 3957 10441
TIME...MOT...LOC 2229Z 273DEG 18KT 3968 10472 

$$

DANKERS

The office that day

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

Issued	Product	Office	Counties	Lasted
May 19, 8:28 PM MDT	Severe Thunderstorm Warning	BOU	Sedgwick	32 min
May 20, 4:33 AM MDT	Special Weather Statement	BOU	Logan	42 min
May 20, 2:33 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Denver, Jefferson	42 min
May 20, 3:15 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe, Denver, Jefferson	45 min
May 20, 4:56 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe	49 min
May 20, 5:36 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe, Elbert, Lincoln, Washington	39 min

Nearby

Tornado Warnings in Colorado, 2014 Every tornado warning in 2014 Tornadoes in 2014

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.