Alert archive / Colorado / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 21, NWS Grand Junction, CO

August 31, 2018Mesa County, Colorado

NWS Grand Junction, CO issued this severe thunderstorm warning at Aug 31, 2018, 7:25 PM MDT for Mesa County, Colorado. It was in force for 35 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: Aug 31, 2018, 7:25 PM MDT (01:25 UTC)
Expired: Aug 31, 2018, 8:00 PM MDT
In force: 35 min
Issued by: NWS Grand Junction, CO
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

County Mesa County, CO

The radar

The Grand Junction radar (KGJX), 26 km from the middle of the area, began a volume at 01:25 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 nearest sounding before it

Grand Junction, CO (KGJT), launched 00:00Z, 1.4 hours before the alert went out and 2 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: 437 J/kg
Mixed-layer CIN: -14 J/kg
Mixed-layer LCL: 3341 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 4 m²/s²
0-3 km storm-relative helicity: 10 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

The text

As transmitted.

303 
WUUS55 KGJT 010125
SVRGJT
COC077-010200-
/O.NEW.KGJT.SV.W.0021.180901T0125Z-180901T0200Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Grand Junction CO
725 PM MDT FRI AUG 31 2018

The National Weather Service in Grand Junction has issued a

* Severe Thunderstorm Warning for...
  Northwestern Mesa County in west central Colorado...

* Until 800 PM MDT.

* At 724 PM MDT, a severe thunderstorm was located over Grand
  Junction, moving northeast at 30 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Locations impacted include...
  Grand Junction, Palisade, Cameo, Fruitvale, Clifton, Orchard Mesa
  and Redlands.

This includes the following highways...
 Interstate 70 in Colorado between mile markers 24 and 47.
 U.S. Highway 50 in Colorado between mile markers 32 and 37.
 Colorado 141 between mile markers 159 and 162.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3898 10861 3907 10871 3932 10851 3925 10835
      3911 10827
TIME...MOT...LOC 0124Z 226DEG 25KT 3907 10860 

HAIL...<.75IN
WIND...60MPH
 
$$

Charnick

4 follow-up statements

871 
WWUS55 KGJT 010134
SVSGJT

Severe Weather Statement
National Weather Service Grand Junction CO
734 PM MDT FRI AUG 31 2018

COC077-010200-
/O.CON.KGJT.SV.W.0021.000000T0000Z-180901T0200Z/
Mesa CO-
734 PM MDT FRI AUG 31 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 800 PM MDT
FOR NORTH CENTRAL MESA COUNTY...

At 734 PM MDT, a severe thunderstorm was located over Grand Junction,
moving northeast at 30 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Grand Junction, Palisade, Clifton, Orchard Mesa, Cameo and Fruitvale.

This includes the following highways...
 Interstate 70 in Colorado between mile markers 28 and 47.
 U.S. Highway 50 in Colorado between mile markers 36 and 37.
 Colorado 141 between mile markers 159 and 162.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3901 10852 3907 10854 3911 10859 3913 10866
      3932 10851 3925 10835 3911 10827
TIME...MOT...LOC 0134Z 226DEG 25KT 3912 10853 

HAIL...<.75IN
WIND...60MPH
 
$$

Charnick

327 
WWUS55 KGJT 010143
SVSGJT

Severe Weather Statement
National Weather Service Grand Junction CO
743 PM MDT FRI AUG 31 2018

COC077-010200-
/O.CON.KGJT.SV.W.0021.000000T0000Z-180901T0200Z/
Mesa CO-
743 PM MDT FRI AUG 31 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 800 PM MDT
FOR NORTH CENTRAL MESA COUNTY...

At 742 PM MDT, a severe thunderstorm was located near Grand Junction,
moving northeast at 30 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Palisade, Clifton, Cameo and Fruitvale. 

This includes the following highways...
 Interstate 70 in Colorado between mile markers 36 and 47.
 Colorado 141 between mile markers 159 and 162.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3903 10846 3910 10847 3915 10851 3918 10855
      3928 10843 3925 10835 3911 10827
TIME...MOT...LOC 0142Z 226DEG 25KT 3916 10847 

HAIL...<.75IN
WIND...60MPH
 
$$

Charnick

127 
WWUS55 KGJT 010153
SVSGJT

Severe Weather Statement
National Weather Service Grand Junction CO
753 PM MDT FRI AUG 31 2018

COC077-010200-
/O.CON.KGJT.SV.W.0021.000000T0000Z-180901T0200Z/
Mesa CO-
753 PM MDT FRI AUG 31 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 800 PM MDT
FOR NORTHEASTERN MESA COUNTY...

At 752 PM MDT, a severe thunderstorm was located 7 miles north of
Palisade, or 11 miles northeast of Grand Junction, moving northeast
at 30 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Palisade and Cameo. 

This includes Interstate 70 in Colorado between mile markers 41 and
47.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3908 10835 3914 10838 3918 10841 3925 10835
      3911 10827
TIME...MOT...LOC 0152Z 226DEG 25KT 3921 10840 

HAIL...<.75IN
WIND...60MPH
 
$$

Charnick

396 
WWUS55 KGJT 010155
SVSGJT

Severe Weather Statement
National Weather Service Grand Junction CO
755 PM MDT FRI AUG 31 2018

COC077-010204-
/O.EXP.KGJT.SV.W.0021.000000T0000Z-180901T0200Z/
Mesa CO-
755 PM MDT FRI AUG 31 2018

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN MESA COUNTY WILL
EXPIRE AT 800 PM MDT...
    
The severe thunderstorm which prompted the warning has weakenedand 
moved out of the warned area. Therefore the warning will be allowed 
to expire.

LAT...LON 3908 10835 3914 10838 3918 10841 3925 10835
      3911 10827
TIME...MOT...LOC 0154Z 226DEG 25KT 3922 10839 

$$

Charnick

The office that day

Everything else NWS Grand Junction, CO issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 31, 7:16 PM MDT	Special Weather Statement	GJT	Mesa	44 min
Aug 31, 8:07 PM MDT	Special Weather Statement	GJT	Garfield	23 min
Sep 1, 11:23 AM MDT	Special Weather Statement	GJT	La Plata	52 min
Sep 1, 1:07 PM MDT	Special Weather Statement	GJT	Montezuma	38 min
Sep 1, 1:49 PM MDT	Special Weather Statement	GJT	La Plata	41 min
Sep 1, 1:52 PM MDT	Special Weather Statement	GJT	Montezuma	23 min

Nearby

Severe Thunderstorm Warnings in Colorado, 2018 Every severe thunderstorm warning 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.