Alert archive / Utah / Mesoscale Discussions in 2018

Mesoscale Discussion 1333

August 21, 2018Mesa County, Colorado; 6 counties in Utah

The Storm Prediction Center issued this mesoscale discussion at Aug 21, 2018, 11:20 AM MDT for Mesa County, Colorado; 6 counties in Utah. It was in force for 115 min.

The area

The outline as issued.

The facts

Issued
Aug 21, 2018, 11:20 AM MDT (17:20 UTC)
Expired
Aug 21, 2018, 1:15 PM MDT
In force
115 min
Issued by
the Storm Prediction Center
Chance of a watch
20%

Counties Mesa County, CO, Emery County, UT, Garfield County, UT, Grand County, UT, Piute County, UT, Sevier County, UT, Wayne County, UT

The radar

The Cedar City radar (KICX), 180 km from the middle of the area, began a volume at 17:19 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, 5.3 hours before the alert went out and 240 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, Grand Junction, CO at 12:00Z on 2018-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 11 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Grand Junction, CO at 12:00Z on 2018-08-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 11 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
11 J/kg
Mixed-layer CIN
-403 J/kg
Mixed-layer LCL
2499 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
11 m²/s²
0-3 km storm-relative helicity
121 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 21, 2:57 PM MDTMesoscale DiscussionSPCBaca, Las Animas2 hr

Nearby

Mesoscale Discussions in Utah, 2018Mesoscale Discussions in Colorado, 2018Every mesoscale discussion 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.