Alert archive / Oklahoma / Mesoscale Discussions in 2025

Mesoscale Discussion 862

May 18, 2025Ellis County, Harper County, Woodward County, Oklahoma

The Storm Prediction Center issued this mesoscale discussion at May 18, 2025, 5:11 PM CDT for Ellis County, Harper County, Woodward County, Oklahoma. It was in force for 94 min.

The area

The outline as issued.

The facts

Issued: May 18, 2025, 5:11 PM CDT (22:11 UTC)
Expired: May 18, 2025, 6:45 PM CDT
In force: 94 min
Issued by: the Storm Prediction Center
Concerning: Tornado watch 287

Counties Ellis County, OK, Harper County, OK, Woodward County, OK

The radar

The Vance AFB radar (KVNX), 142 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

Dodge City, (KDDC), launched 12:00Z, 10.2 hours before the alert went out and 157 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: 723 J/kg
Mixed-layer CIN: -377 J/kg
Mixed-layer LCL: 1181 m above ground
0-6 km bulk shear: 47 kt
0-1 km storm-relative helicity: 206 m²/s²
0-3 km storm-relative helicity: 225 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.4

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
May 17, 7:40 PM CDT	Mesoscale Discussion	SPC	Atoka, Beckham, Blaine, Bryan, Caddo, Canadian and 33 more	2 hr
May 17, 7:49 PM CDT	Severe Thunderstorm Watch	SPC	McCurtain	6 hr
May 17, 9:53 PM CDT	Mesoscale Discussion	SPC	Choctaw, Latimer, LeFlore, McCurtain, Pushmataha	2 hr
May 17, 9:54 PM CDT	Severe Thunderstorm Watch	SPC	Adair, Blaine, Caddo, Canadian, Cherokee, Cleveland and 31 more	8 hr
May 17, 11:30 PM CDT	Mesoscale Discussion	SPC	Blaine, Caddo, Canadian, Cleveland, Creek, Garvin and 16 more	2 hr
May 18, 3:15 AM CDT	Mesoscale Discussion	SPC	Adair, Cherokee, Haskell, Latimer, LeFlore, McIntosh and 7 more	60 min
May 18, 4:23 AM CDT	Mesoscale Discussion	SPC	Adair, Cherokee, Haskell, Latimer, LeFlore, Sequoyah	67 min
May 18, 11:40 AM CDT	Mesoscale Discussion	SPC	Adair, Cherokee, Delaware, Mayes, Muskogee, Sequoyah and 1 more	2 hr
May 18, 3:21 PM CDT	Mesoscale Discussion	SPC	Alfalfa, Beaver, Beckham, Blaine, Caddo, Canadian and 15 more	114 min
May 18, 3:38 PM CDT	Tornado Watch	SPC	Alfalfa, Beaver, Beckham, Blaine, Caddo, Canadian and 26 more	8 hr

Nearby

Mesoscale Discussions in Oklahoma, 2025 Every mesoscale discussion in 2025

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.