Alert archive / Idaho / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 35, NWS Boise, ID

May 31, 2018Twin Falls County, Idaho

NWS Boise, ID issued this severe thunderstorm warning at May 31, 2018, 12:49 PM MDT for Twin Falls County, Idaho. It was in force for 41 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: May 31, 2018, 12:49 PM MDT (18:49 UTC)
Expired: May 31, 2018, 1:30 PM MDT
In force: 41 min
Issued by: NWS Boise, ID
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Twin Falls County, ID

The radar

The Boise radar (KCBX), 180 km from the middle of the area, began a volume at 18:49 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

Elko, NV (KLKN), launched 12:00Z, 6.8 hours before the alert went out and 170 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: 16 J/kg
Mixed-layer CIN: -37 J/kg
Mixed-layer LCL: 1320 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 32 m²/s²
0-3 km storm-relative helicity: 61 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 Boise, ID wrote its last area forecast discussion before this severe thunderstorm warning went out at May 31, 9:18 AM MDT, 3 hours 31 minutes earlier.

Area forecast discussion, May 31, 9:18 AM MDT, 3 hours 31 minutes before

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In the hours before

Special weather statement, May 31, 12:27 PM MDT, 22 minutes before

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The office that day

Everything else NWS Boise, ID issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 30, 6:00 PM MDT	Severe Thunderstorm Warning	BOI	Jerome, Twin Falls	30 min
May 30, 6:32 PM MDT	Special Weather Statement	BOI	Jerome	28 min
May 30, 6:59 PM MDT	Special Weather Statement	BOI	Canyon	31 min
May 30, 7:28 PM MDT	Special Weather Statement	BOI	Ada	32 min
May 30, 8:01 PM MDT	Special Weather Statement	BOI	Boise	29 min
May 31, 12:27 PM MDT	Special Weather Statement	BOI	Gooding, Jerome, Twin Falls	63 min
May 31, 1:27 PM MDT	Severe Thunderstorm Warning	BOI	Jerome, Twin Falls	38 min
May 31, 1:33 PM MDT	Severe Thunderstorm Warning	BOI	Owyhee, Twin Falls	27 min
May 31, 1:58 PM MDT	Special Weather Statement	BOI	Twin Falls	32 min
May 31, 2:32 PM MDT	Special Weather Statement	BOI	Twin Falls	28 min

Nearby

Severe Thunderstorm Warnings in Idaho, 2018 Every severe thunderstorm warning in 2018

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.