Alert archive / Colorado / Tornado Warnings in 2010

Tornado Warning 21, NWS Denver/Boulder, CO

May 18, 2010Weld County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at May 18, 2010, 5:46 PM MDT for Weld County, Colorado. It was in force for 44 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 18, 2010, 5:46 PM MDT (23:46 UTC)
Expired
May 18, 2010, 6:30 PM MDT
In force
44 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon

County Weld County, CO

The radar

The Cheyenne radar (KCYS), 36 km from the middle of the area, began a volume at 23:47 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.

IssuedProductOfficeLasted
May 18, 12:41 PM MDTTornado WatchSPC10 hr

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 11.8 hours before the alert went out and 162 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 2010-05-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 482 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 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 2010-05-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 62 square meters per square second.193958Sfc1 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
482 J/kg
Mixed-layer CIN
-196 J/kg
Mixed-layer LCL
1137 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
62 m²/s²
0-3 km storm-relative helicity
51 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.

063 
WFUS55 KBOU 182346
TORBOU
COC123-190030-
/O.NEW.KBOU.TO.W.0021.100518T2346Z-100519T0030Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DENVER CO
546 PM MDT TUE MAY 18 2010

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

* TORNADO WARNING FOR...
  NORTH CENTRAL WELD COUNTY IN NORTHEAST COLORADO

* UNTIL 630 PM MDT

* AT 546 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO 7 MILES
  NORTHEAST OF NUNN...OR 25 MILES NORTH OF GREELEY. THIS STORM WAS
  MOVING NORTHEAST AT 15 MPH.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO ROCKPORT...
  NUNN AND CARR.

THIS TORNADO WARNING REPLACES THE TORNADO WARNING THAT WAS IN EFFECT 
FOR NORTHWEST WELD COUNTY UNTIL 545 PM MDT. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOTORISTS SHOULD NOT TAKE SHELTER UNDER HIGHWAY OVERPASSES. AS A LAST
RESORT...EITHER PARK YOUR VEHICLE AND STAY PUT...OR ABANDON YOUR
VEHICLE AND LIE DOWN IN A LOW LYING AREA.

&&

LAT...LON 4099 10444 4064 10451 4065 10489 4100 10489
TIME...MOT...LOC 2346Z 225DEG 13KT 4078 10468

$$
2 follow-up statements
294 
WWUS55 KBOU 190009
SVSBOU

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
609 PM MDT TUE MAY 18 2010

COC123-190030-
/O.CON.KBOU.TO.W.0021.000000T0000Z-100519T0030Z/
WELD CO-
609 PM MDT TUE MAY 18 2010

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 630 PM MDT FOR NORTH
CENTRAL WELD COUNTY...

AT 607 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A 
THUNDERSTORM CAPABLE OF PRODUCING A TORNADO LOCATED 9 MILES 
SOUTHEAST OF ROCKPORT...OR 30 MILES NORTH OF GREELEY. THIS STORM WAS 
MOVING NORTHEAST AT 15 MPH.

TRAINED WEATHER SPOTTERS HAVE REPORTED FUNNEL CLOUDS WITH THESE 
THUNDERSTORMS. LARGE HAIL AND HEAVY RAINS WILL ALSO BE POSSIBLE AS 
THE STORM MOVES OVER NORTHWEST WELD COUNTY.

LOCATIONS REMAINING IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
ROCKPORT...NUNN AND CARR.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOTORISTS SHOULD NOT TAKE SHELTER UNDER HIGHWAY OVERPASSES. AS A LAST
RESORT...EITHER PARK YOUR VEHICLE AND STAY PUT...OR ABANDON YOUR
VEHICLE AND LIE DOWN IN A LOW LYING AREA.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 900 PM MDT TUESDAY EVENING
FOR NORTHEASTERN COLORADO.

&&

LAT...LON 4099 10444 4064 10451 4065 10489 4100 10489
TIME...MOT...LOC 0007Z 215DEG 15KT 4086 10462

$$
436 
WWUS55 KBOU 190026
SVSBOU

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
626 PM MDT TUE MAY 18 2010

COC123-190034-
/O.EXP.KBOU.TO.W.0021.000000T0000Z-100519T0030Z/
WELD CO-
626 PM MDT TUE MAY 18 2010

...THE TORNADO WARNING FOR NORTH CENTRAL WELD COUNTY WILL EXPIRE AT
630 PM MDT...

THE THUNDERSTORM THAT PROMPTED THE WARNING HAS WEAKENED AND IS NO 
LONGER EXPECTED TO PRODUCE SEVERE WEATHER. SCATTERED THUNDERSTORMS 
OVER THE NORTHWEST WELD COUNTY WILL CONTINUE THROUGH 700 PM MDT WITH 
THE POTENTIAL TO PRODUCE PERIODS OF HEAVY RAIN AND SMALL HAIL. 

A TORNADO WATCH REMAINS IN EFFECT UNTIL 900 PM MDT TUESDAY EVENING
FOR NORTHEASTERN COLORADO.

LAT...LON 4099 10444 4064 10451 4065 10489 4100 10489
TIME...MOT...LOC 0024Z 225DEG 18KT 4092 10454

$$

The office that day

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

IssuedProductOfficeCountiesLasted
May 18, 3:36 PM MDTTornado WarningBOUWeld24 min
May 18, 3:51 PM MDTTornado WarningBOULogan, Weld39 min
May 18, 4:03 PM MDTSevere Thunderstorm WarningBOUAdams, Denver, Weld42 min
May 18, 5:18 PM MDTTornado WarningBOUWeld27 min
May 18, 5:28 PM MDTTornado WarningBOUWeld36 min

Nearby

Tornado Warnings in Colorado, 2010Every tornado warning in 2010Tornadoes in 2010

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.