Alert archive / California / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 6, NWS Medford, OR

July 22, 2018Siskiyou County, California

NWS Medford, OR issued this severe thunderstorm warning at Jul 22, 2018, 7:31 PM PDT for Siskiyou County, California. It was in force for 29 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 22, 2018, 7:31 PM PDT (02:31 UTC)
Expired: Jul 22, 2018, 8:00 PM PDT
In force: 29 min
Issued by: NWS Medford, OR
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Siskiyou County, CA

The radar

The Medford radar (KMAX), 56 km from the middle of the area, began a volume at 02:34 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

Reno, NV (KREV), launched 00:00Z, 2.5 hours before the alert went out and 430 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: 845 J/kg
Mixed-layer CIN: -27 J/kg
Mixed-layer LCL: 2331 m above ground
0-6 km bulk shear: 19 kt
0-1 km storm-relative helicity: -9 m²/s²
0-3 km storm-relative helicity: 39 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 Medford, OR wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 22, 2:40 PM PDT, 4 hours 51 minutes earlier.

Area forecast discussion, Jul 22, 2:40 PM PDT, 4 hours 51 minutes before

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In the hours before

Special weather statement, Jul 22, 6:13 PM PDT, 1 hour 18 minutes before

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Special weather statement, Jul 22, 6:20 PM PDT, 1 hour 11 minutes before

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Special weather statement, Jul 22, 6:49 PM PDT, 42 minutes before

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Special weather statement, Jul 22, 6:54 PM PDT, 37 minutes before

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Special weather statement, Jul 22, 7:07 PM PDT, 24 minutes before

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Special weather statement, Jul 22, 7:14 PM PDT, 17 minutes before

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The office that day

Everything else NWS Medford, OR issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 22, 5:02 PM PDT	Special Weather Statement	MFR		28 min
Jul 22, 6:13 PM PDT	Special Weather Statement	MFR	Siskiyou	32 min
Jul 22, 6:20 PM PDT	Special Weather Statement	MFR	Modoc	25 min
Jul 22, 6:49 PM PDT	Special Weather Statement	MFR	Modoc	26 min
Jul 22, 6:54 PM PDT	Special Weather Statement	MFR	Siskiyou	36 min
Jul 22, 7:07 PM PDT	Special Weather Statement	MFR	Siskiyou	23 min
Jul 22, 7:14 PM PDT	Special Weather Statement	MFR	Siskiyou	31 min
Jul 22, 7:38 PM PDT	Special Weather Statement	MFR	Siskiyou	37 min
Jul 22, 7:50 PM PDT	Special Weather Statement	MFR	Modoc	10 min
Jul 22, 8:14 PM PDT	Special Weather Statement	MFR	Siskiyou	31 min
Jul 22, 8:19 PM PDT	Special Weather Statement	MFR	Modoc	26 min
Jul 22, 8:45 PM PDT	Special Weather Statement	MFR	Siskiyou	30 min
Jul 22, 9:25 PM PDT	Special Weather Statement	MFR	Siskiyou	35 min
Jul 22, 10:11 PM PDT	Special Weather Statement	MFR	Siskiyou	34 min
Jul 22, 10:45 PM PDT	Special Weather Statement	MFR	Siskiyou	30 min

Nearby

Severe Thunderstorm Warnings in California, 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.