Alert archive / Wyoming / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 36, NWS Riverton, WY

July 5, 2020Johnson County, Wyoming

NWS Riverton, WY issued this severe thunderstorm warning at Jul 5, 2020, 5:39 PM MDT for Johnson County, Wyoming. It was in force for 51 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: Jul 5, 2020, 5:39 PM MDT (23:39 UTC)
Expired: Jul 5, 2020, 6:30 PM MDT
In force: 51 min
Issued by: NWS Riverton, WY
Area: Storm-based polygon
Hail: 1.25 in
Wind: 60.0 mph

County Johnson County, WY

The radar

The Riverton/Lander radar (KRIW), 187 km from the middle of the area, began a volume at 23:42 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Jul 5, 4:13 PM MDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Riverton, WY (KRIW), launched 12:00Z, 11.7 hours before the alert went out and 182 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: 14 J/kg
Mixed-layer CIN: -352 J/kg
Mixed-layer LCL: 2703 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 62 m²/s²
0-3 km storm-relative helicity: 136 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 Riverton, WY wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 5, 5:23 PM MDT, 16 minutes earlier.

Area forecast discussion, Jul 5, 5:23 PM MDT, 16 minutes before

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Hazardous weather outlook, Jul 5, 1:36 PM MDT, 4 hours 3 minutes before

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In the hours before

Special weather statement, Jul 5, 4:37 PM MDT, 1 hour 2 minutes before

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Special weather statement, Jul 5, 4:52 PM MDT, 47 minutes before

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Special weather statement, Jul 5, 4:52 PM MDT, 47 minutes before

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Special weather statement, Jul 5, 5:17 PM MDT, 22 minutes before

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Special weather statement, Jul 5, 5:34 PM MDT, 5 minutes before

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Special weather statement, Jul 5, 5:36 PM MDT, 3 minutes before

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      <p id="message2">
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        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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The office that day

Everything else NWS Riverton, WY issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 4, 6:10 PM MDT	Special Weather Statement	RIW	Johnson	50 min
Jul 5, 8:49 AM MDT	Fire Weather Watch	RIW	Fremont, Hot Springs, Johnson, Natrona, Washakie	28 hr
Jul 5, 1:28 PM MDT	Red Flag Warning	RIW	Fremont, Hot Springs, Johnson, Natrona, Washakie	3 days
Jul 5, 2:40 PM MDT	Special Weather Statement	RIW	Natrona	35 min
Jul 5, 3:18 PM MDT	Special Weather Statement	RIW	Natrona	27 min
Jul 5, 3:23 PM MDT	Special Weather Statement	RIW	Natrona	37 min
Jul 5, 3:25 PM MDT	Special Weather Statement	RIW	Natrona	35 min
Jul 5, 3:45 PM MDT	Severe Thunderstorm Warning	RIW	Johnson, Natrona	45 min
Jul 5, 3:55 PM MDT	Special Weather Statement	RIW	Natrona	35 min
Jul 5, 4:24 PM MDT	Special Weather Statement	RIW	Johnson	51 min
Jul 5, 4:33 PM MDT	Special Weather Statement	RIW	Natrona	12 min
Jul 5, 4:37 PM MDT	Special Weather Statement	RIW	Washakie	23 min
Jul 5, 4:52 PM MDT	Special Weather Statement	RIW	Johnson	23 min
Jul 5, 4:56 PM MDT	Severe Thunderstorm Warning	RIW	Johnson	49 min
Jul 5, 5:17 PM MDT	Special Weather Statement	RIW		28 min
Jul 5, 5:34 PM MDT	Special Weather Statement	RIW		26 min
Jul 5, 5:36 PM MDT	Special Weather Statement	RIW	Johnson	24 min
Jul 5, 5:56 PM MDT	Special Weather Statement	RIW		34 min

Nearby

Severe Thunderstorm Warnings in Wyoming, 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.