Alert archive / Colorado / Tornado Warnings in 2018

Tornado Warning 6, NWS Denver/Boulder, CO

May 27, 2018Morgan County, Weld County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at May 27, 2018, 4:58 PM MDT for Morgan County, Weld County, Colorado. It was in force for 18 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 27, 2018, 4:58 PM MDT (22:58 UTC)
Expired
May 27, 2018, 5:16 PM MDT
In force
18 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon
Tornado
Radar indicated
Hail
1.25 in

Counties Morgan County, CO, Weld County, CO

The radar

The Denver radar (KFTG), 111 km from the middle of the area, began a volume at 23:00 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 27, 1:13 PM MDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Denver, CO (KDEN), launched 12:00Z, 11.0 hours before the alert went out and 85 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 2018-05-27Temperature 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 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 2018-05-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 20 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
4365 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
20 m²/s²
0-3 km storm-relative helicity
105 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

470 
WFUS55 KBOU 272258
TORBOU
COC087-123-272330-
/O.NEW.KBOU.TO.W.0006.180527T2258Z-180527T2330Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Denver CO
458 PM MDT SUN MAY 27 2018

The National Weather Service in Denver Colorado has issued a

* Tornado Warning for...
  East central Weld County in northeastern Colorado...
  Northeastern Morgan County in northeastern Colorado...

* Until 530 PM MDT.
    
* At 457 PM MDT, a severe thunderstorm capable of producing a tornado
  was located near Antelope Springs, or 15 miles north of Fort
  Morgan, moving north at 25 mph.

  HAZARD...Tornado and half dollar 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...
  Stoneham, New Raymer and Antelope Springs. 

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 outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4058 10358 4053 10358 4052 10357 4039 10355
      4040 10393 4047 10395 4072 10389 4072 10360
TIME...MOT...LOC 2257Z 185DEG 23KT 4048 10376 

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

$$

RPK
1 follow-up statement
085 
WWUS55 KBOU 272316
SVSBOU

Severe Weather Statement
National Weather Service Denver CO
516 PM MDT SUN MAY 27 2018

COC087-123-272326-
/O.CAN.KBOU.TO.W.0006.000000T0000Z-180527T2330Z/
Weld CO-Morgan CO-
516 PM MDT SUN MAY 27 2018

...THE TORNADO WARNING FOR EAST CENTRAL WELD AND NORTHEASTERN MORGAN
COUNTIES IS CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning has been cancelled.  However small hail and
gusty winds are still possible with this thunderstorm.

A Severe Thunderstorm Watch remains in effect until 800 PM MDT for
northeastern Colorado.

LAT...LON 4058 10358 4053 10358 4052 10357 4039 10355
      4040 10393 4047 10395 4072 10389 4072 10360
TIME...MOT...LOC 2315Z 185DEG 23KT 4060 10375 

$$

RPK

The office that day

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

IssuedProductOfficeCountiesLasted
May 27, 12:27 PM MDTSpecial Weather StatementBOULarimer33 min
May 27, 1:45 PM MDTTornado WarningBOUAdams, Weld30 min
May 27, 2:14 PM MDTSevere Thunderstorm WarningBOUWeld31 min
May 27, 2:23 PM MDTSevere Thunderstorm WarningBOUPhillips50 min
May 27, 2:44 PM MDTSevere Thunderstorm WarningBOUMorgan, Weld31 min
May 27, 2:47 PM MDTSevere Thunderstorm WarningBOULincoln31 min
May 27, 3:06 PM MDTTornado WarningBOUMorgan, Weld24 min
May 27, 3:36 PM MDTSpecial Weather StatementBOULincoln24 min
May 27, 4:20 PM MDTSevere Thunderstorm WarningBOUWashington40 min
May 27, 4:28 PM MDTTornado WarningBOUMorgan17 min
May 27, 4:37 PM MDTTornado WarningBOUMorgan23 min
May 27, 5:21 PM MDTSpecial Weather StatementBOULogan39 min
May 27, 5:38 PM MDTSevere Thunderstorm WarningBOULogan52 min

Nearby

Tornado Warnings in Colorado, 2018Every tornado warning in 2018Tornadoes in 2018

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.