Alert archive / Oklahoma / Mesoscale Discussions in 2015

Mesoscale Discussion 174

April 1, 2015Polk County, Scott County, Arkansas; 8 counties in Oklahoma

The Storm Prediction Center issued this mesoscale discussion at Apr 1, 2015, 1:16 AM CDT for Polk County, Scott County, Arkansas; 8 counties in Oklahoma. It was in force for 89 min.

The area

The outline as issued.

The facts

Issued: Apr 1, 2015, 1:16 AM CDT (06:16 UTC)
Expired: Apr 1, 2015, 2:45 AM CDT
In force: 89 min
Issued by: the Storm Prediction Center

Counties Polk County, AR, Scott County, AR, Coal County, OK, Haskell County, OK, Hughes County, OK, Latimer County, OK, LeFlore County, OK, McIntosh County, OK, Okfuskee County, OK, Pittsburg County, OK

The radar

The Western Arkansas radar (KSRX), 104 km from the middle of the area, began a volume at 06:17 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

Norman, OK (KOUN), launched 00:00Z, 6.3 hours before the alert went out and 185 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: 1642 J/kg
Mixed-layer CIN: -15 J/kg
Mixed-layer LCL: 1964 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 5 m²/s²
0-3 km storm-relative helicity: 79 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 3.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Mar 31, 8:14 PM CDT	Mesoscale Discussion	SPC	Crawford, Franklin, Sebastian	91 min
Mar 31, 8:50 PM CDT	Mesoscale Discussion	SPC	Clay, Cleburne, Craighead, Crittenden, Cross, Faulkner and 10 more	85 min
Mar 31, 11:43 PM CDT	Mesoscale Discussion	SPC	Crittenden, Cross, Poinsett	92 min
Apr 1, 12:39 PM CDT	Mesoscale Discussion	SPC	Baxter, Benton, Boone, Carroll, Crawford, Franklin and 8 more	3 hr
Apr 1, 5:14 PM CDT	Mesoscale Discussion	SPC	Arkansas, Baxter, Boone, Carroll, Clark, Clay and 54 more	91 min
Mar 31, 9:24 PM CDT	Mesoscale Discussion	SPC	Atoka, Beckham, Caddo, Canadian, Carter, Choctaw and 29 more	66 min
Mar 31, 9:40 PM CDT	Severe Thunderstorm Watch	SPC	Blaine, Caddo, Canadian, Carter, Cleveland, Coal and 31 more	6 hr
Apr 1, 3:57 PM CDT	Mesoscale Discussion	SPC	Beaver, Beckham, Ellis, Harper, Roger Mills	93 min

Nearby

Mesoscale Discussions in Oklahoma, 2015 Mesoscale Discussions in Arkansas, 2015 Every mesoscale discussion in 2015

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.