Alert archive / Utah / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 4, NWS Grand Junction, CO

May 24, 2009Grand County, Utah

NWS Grand Junction, CO issued this severe thunderstorm warning at May 24, 2009, 4:08 PM MDT for Grand County, Utah. It was in force for 29 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: May 24, 2009, 4:08 PM MDT (22:08 UTC)
Expired: May 24, 2009, 4:37 PM MDT
In force: 29 min
Issued by: NWS Grand Junction, CO
Area: Storm-based polygon

County Grand County, UT

The radar

The Grand Junction radar (KGJX), 118 km from the middle of the area, began a volume at 22:11 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 12:00Z, 10.1 hours before the alert went out and 94 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: 143 J/kg
Mixed-layer CIN: -21 J/kg
Mixed-layer LCL: 888 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 95 m²/s²
0-3 km storm-relative helicity: 114 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.4

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Grand Junction, CO wrote its last area forecast discussion before this severe thunderstorm warning went out at May 24, 2:14 PM MDT, 1 hour 54 minutes earlier.

Area forecast discussion, May 24, 2:14 PM MDT, 1 hour 54 minutes before

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Hazardous weather outlook, May 24, 6:02 AM MDT, 10 hours 6 minutes before

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In the hours before

Local storm report, May 24, 1:51 PM MDT, 2 hours 17 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
May 23, 11:32 PM MDT	Areal Flood Advisory	GJT	Garfield, Gunnison, Mesa, Pitkin	3 hr
May 24, 1:04 AM MDT	Areal Flood Advisory	GJT	Mesa	3 hr
May 24, 2:01 AM MDT	Flash Flood Watch	GJT	Delta, Dolores, Garfield, Gunnison, La Plata, Mesa and 5 more	20 hr
May 24, 5:51 AM MDT	Areal Flood Advisory	GJT	Mesa	3 hr

Nearby

Severe Thunderstorm Warnings in Utah, 2009 Every severe thunderstorm warning in 2009

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.