Alert archive / Arkansas / Mesoscale Discussions in 2017

Mesoscale Discussion 584

April 28, 20175 counties in Arkansas

The Storm Prediction Center issued this mesoscale discussion at Apr 28, 2017, 10:49 PM CDT for 5 counties in Arkansas. It was in force for 56 min.

The area

The outline as issued.

The facts

Issued: Apr 28, 2017, 10:49 PM CDT (03:49 UTC)
Expired: Apr 28, 2017, 11:45 PM CDT
In force: 56 min
Issued by: the Storm Prediction Center

Counties Johnson County, AR, Logan County, AR, Pope County, AR, Searcy County, AR, Van Buren County, AR

The radar

The Western Arkansas radar (KSRX), 106 km from the middle of the area, began a volume at 03:53 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

Springfield, MO (KSGF), launched 00:00Z, 3.8 hours before the alert went out and 158 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: 65 J/kg
Mixed-layer CIN: -331 J/kg
Mixed-layer LCL: 506 m above ground
0-6 km bulk shear: 74 kt
0-1 km storm-relative helicity: 55 m²/s²
0-3 km storm-relative helicity: 72 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.

Issued	Product	Office	Counties	Lasted
Apr 28, 10:01 PM CDT	Severe Thunderstorm Watch	SPC	Baxter, Benton, Boone, Carroll, Crawford, Franklin and 8 more	9 hr
Apr 28, 11:55 PM CDT	Mesoscale Discussion	SPC	Baxter, Benton, Boone, Carroll, Clay, Crawford and 12 more	95 min
Apr 29, 3:39 AM CDT	Mesoscale Discussion	SPC	Benton, Boone, Carroll, Madison, Washington	96 min
Apr 29, 1:11 PM CDT	Mesoscale Discussion	SPC	Benton, Conway, Crawford, Franklin, Garland, Hot Spring and 15 more	2 hr
Apr 29, 5:36 PM CDT	Severe Thunderstorm Watch	SPC	Baxter, Boone, Carroll, Crawford, Franklin, Fulton and 9 more	4 hr
Apr 29, 6:21 PM CDT	Mesoscale Discussion	SPC	Arkansas, Bradley, Calhoun, Chicot, Cleveland, Craighead and 20 more	54 min

Nearby

Mesoscale Discussions in Arkansas, 2017 Every mesoscale discussion in 2017

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.