Alert archive / Iowa / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 144, NWS Quad Cities, IA

September 18, 2019Benton County, Buchanan County, Linn County, Iowa

NWS Quad Cities, IA issued this severe thunderstorm warning at Sep 18, 2019, 2:40 PM CDT for Benton County, Buchanan County, Linn County, Iowa. It was in force for 50 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: Sep 18, 2019, 2:40 PM CDT (19:40 UTC)
Expired: Sep 18, 2019, 3:30 PM CDT
In force: 50 min
Issued by: NWS Quad Cities, IA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Benton County, IA, Buchanan County, IA, Linn County, IA

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 7.7 hours before the alert went out and 128 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1018 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: 69 m²/s²
0-3 km storm-relative helicity: 59 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 Quad Cities, IA wrote its last area forecast discussion before this severe thunderstorm warning went out at Sep 18, 12:37 PM CDT, 2 hours 3 minutes earlier.

Area forecast discussion, Sep 18, 12:37 PM CDT, 2 hours 3 minutes before

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Hazardous weather outlook, Sep 18, 4:29 AM CDT, 10 hours 11 minutes before

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In the hours before

Special weather statement, Sep 18, 2:19 PM CDT, 21 minutes before

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The office that day

Everything else NWS Quad Cities, IA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Sep 18, 2:19 PM CDT	Special Weather Statement	DVN	Benton	41 min
Sep 18, 3:27 PM CDT	Special Weather Statement	DVN	Linn	48 min
Sep 18, 4:12 PM CDT	Special Weather Statement	DVN	Johnson, Jones	48 min
Sep 18, 4:57 PM CDT	Special Weather Statement	DVN	Cedar, Muscatine	63 min
Sep 18, 5:30 PM CDT	Special Weather Statement	DVN	Keokuk	30 min
Sep 18, 6:12 PM CDT	Special Weather Statement	DVN	Jefferson	33 min
Sep 18, 6:45 PM CDT	Special Weather Statement	DVN	Keokuk	30 min
Sep 18, 5:32 PM CDT	Special Weather Statement	DVN	Clark	28 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2019 Every severe thunderstorm warning in 2019

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.