Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 79, NWS Norman, OK

April 19, 2020Harper County, Oklahoma

NWS Norman, OK issued this severe thunderstorm warning at Apr 19, 2020, 4:44 PM CDT for Harper County, Oklahoma. It was in force for 31 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: Apr 19, 2020, 4:44 PM CDT (21:44 UTC)
Expired: Apr 19, 2020, 5:15 PM CDT
In force: 31 min
Issued by: NWS Norman, OK
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Harper County, OK

The radar

The Dodge City radar (KDDC), 111 km from the middle of the area, began a volume at 21:43 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, 9.7 hours before the alert went out and 111 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: -183 J/kg
Mixed-layer LCL: 1082 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: -62 m²/s²
0-3 km storm-relative helicity: 1 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.0

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 Norman, OK wrote its last area forecast discussion before this severe thunderstorm warning went out at Apr 19, 2:28 PM CDT, 2 hours 16 minutes earlier.

Area forecast discussion, Apr 19, 2:28 PM CDT, 2 hours 16 minutes before

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Hazardous weather outlook, Apr 19, 3:22 PM CDT, 1 hour 22 minutes before

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In the hours before

Special weather statement, Apr 19, 4:15 PM CDT, 29 minutes before

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Special weather statement, Apr 19, 4:43 PM CDT, 1 minute before

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The office that day

Everything else NWS Norman, OK issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 19, 4:15 PM CDT	Special Weather Statement	OUN	Harper	30 min
Apr 19, 4:43 PM CDT	Special Weather Statement	OUN	Harper	32 min
Apr 19, 5:26 PM CDT	Special Weather Statement	OUN	Harper	49 min
Apr 19, 5:53 PM CDT	Severe Thunderstorm Warning	OUN	Ellis, Woodward	52 min
Apr 19, 6:37 PM CDT	Special Weather Statement	OUN	Woods	23 min
Apr 19, 6:47 PM CDT	Special Weather Statement	OUN	Dewey	28 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 2020 Every severe thunderstorm warning in 2020

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.