Alert archive / Wyoming / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 55, NWS Riverton, WY

June 29, 2023Natrona County, Wyoming

NWS Riverton, WY issued this severe thunderstorm warning at Jun 29, 2023, 1:03 PM MDT for Natrona County, Wyoming. It was in force for 42 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: Jun 29, 2023, 1:03 PM MDT (19:03 UTC)
Expired: Jun 29, 2023, 1:45 PM MDT
In force: 42 min
Issued by: NWS Riverton, WY
Area: Storm-based polygon
Tornado: Possible
Hail: 1.5 in
Wind: 60.0 mph

County Natrona County, WY

The radar

The Riverton/Lander radar (KRIW), 137 km from the middle of the area, began a volume at 19:06 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

Riverton, WY (KRIW), launched 12:00Z, 7.1 hours before the alert went out and 131 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: 51 J/kg
Mixed-layer CIN: -125 J/kg
Mixed-layer LCL: 1483 m above ground
0-6 km bulk shear: 8 kt
0-1 km storm-relative helicity: -33 m²/s²
0-3 km storm-relative helicity: 89 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 Jun 28, 4:20 PM MDT, 20 hours 43 minutes earlier.

Area forecast discussion, Jun 28, 4:20 PM MDT, 20 hours 43 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 28, 7:58 PM MDT	Special Weather Statement	RIW		32 min
Jun 28, 8:30 PM MDT	Special Weather Statement	RIW	Johnson	30 min
Jun 29, 12:57 PM MDT	Special Weather Statement	RIW		33 min
Jun 29, 1:32 PM MDT	Special Weather Statement	RIW	Johnson	43 min
Jun 29, 1:42 PM MDT	Severe Thunderstorm Warning	RIW	Johnson	34 min
Jun 29, 1:42 PM MDT	Severe Thunderstorm Warning	RIW	Natrona	48 min
Jun 29, 1:46 PM MDT	Special Weather Statement	RIW	Natrona	44 min
Jun 29, 2:18 PM MDT	Special Weather Statement	RIW	Johnson	27 min
Jun 29, 2:27 PM MDT	Special Weather Statement	RIW	Natrona	33 min
Jun 29, 2:44 PM MDT	Special Weather Statement	RIW		16 min
Jun 29, 2:52 PM MDT	Areal Flood Advisory	RIW	Natrona	6 hr
Jun 29, 3:41 PM MDT	Special Weather Statement	RIW	Natrona	34 min
Jun 29, 3:42 PM MDT	Special Weather Statement	RIW	Natrona	33 min
Jun 29, 3:44 PM MDT	Special Weather Statement	RIW	Natrona	31 min
Jun 29, 3:47 PM MDT	Severe Thunderstorm Warning	RIW	Natrona	28 min
Jun 29, 4:07 PM MDT	Severe Thunderstorm Warning	RIW	Natrona	23 min
Jun 29, 4:13 PM MDT	Special Weather Statement	RIW	Natrona	17 min
Jun 29, 4:19 PM MDT	Special Weather Statement	RIW	Natrona	26 min
Jun 29, 4:23 PM MDT	Special Weather Statement	RIW		37 min
Jun 29, 4:36 PM MDT	Special Weather Statement	RIW		24 min
Jun 29, 4:37 PM MDT	Areal Flood Advisory	RIW	Natrona	4 hr
Jun 29, 5:03 PM MDT	Special Weather Statement	RIW		27 min
Jun 29, 5:06 PM MDT	Special Weather Statement	RIW		24 min
Jun 29, 5:13 PM MDT	Special Weather Statement	RIW	Natrona	17 min
Jun 29, 5:31 PM MDT	Special Weather Statement	RIW		44 min
Jun 29, 5:53 PM MDT	Areal Flood Advisory	RIW	Fremont	4 hr
Jun 29, 5:58 PM MDT	Special Weather Statement	RIW		32 min

Nearby

Severe Thunderstorm Warnings in Wyoming, 2023 Every severe thunderstorm warning in 2023

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.