Alert archive / Michigan / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 91, NWS Detroit, MI

July 21, 1998Macomb County, Michigan

NWS Detroit, MI issued this severe thunderstorm warning at Jul 21, 1998, 5:56 PM EDT for Macomb County, Michigan. It was in force for 64 min. 3 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued: Jul 21, 1998, 5:56 PM EDT (21:56 UTC)
Expired: Jul 21, 1998, 7:00 PM EDT
In force: 64 min
Issued by: NWS Detroit, MI
Area: Whole counties

County Macomb County, MI

The radar

The Detroit radar (KDTX), 46 km from the middle of the area, began a volume at 21:57 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.

What was reported inside it

Time	Report	Where
Jul 21, 6:13 PM EDT	Hail 0.75	Sterling Hgts, MI
Jul 21, 6:17 PM EDT	Thunderstorm Wind 70	Warren, MI
Jul 21, 6:28 PM EDT	Thunderstorm Wind 70	Mt Clemens, MI

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

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 21, 4:00 PM EDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Detroit, MI (KDTX), launched 12:00Z, 9.9 hours before the alert went out and 43 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: 27 J/kg
Mixed-layer CIN: -328 J/kg
Mixed-layer LCL: 2116 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 123 m²/s²
0-3 km storm-relative helicity: 130 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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.

In the hours before

Special weather statement, Jul 21, 12:13 PM EDT, 5 hours 43 minutes before

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Special weather statement, Jul 21, 12:13 PM EDT, 5 hours 43 minutes before

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Special weather statement, Jul 21, 3:56 PM EDT, 2 hours before

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Special weather statement, Jul 21, 3:56 PM EDT, 2 hours before

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<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
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The office that day

Everything else NWS Detroit, MI issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 21, 7:24 AM EDT	Tornado Warning	DTX	Washtenaw	66 min
Jul 21, 7:32 AM EDT	Severe Thunderstorm Warning	DTX	Lenawee	58 min
Jul 21, 8:12 AM EDT	Severe Thunderstorm Warning	DTX	Monroe	33 min
Jul 21, 5:23 PM EDT	Severe Thunderstorm Warning	DTX	Livingston	37 min
Jul 21, 5:33 PM EDT	Severe Thunderstorm Warning	DTX	Washtenaw	57 min
Jul 21, 5:38 PM EDT	Severe Thunderstorm Warning	DTX	Lenawee	57 min
Jul 21, 5:48 PM EDT	Severe Thunderstorm Warning	DTX	Oakland	42 min
Jul 21, 5:56 PM EDT	Severe Thunderstorm Warning	DTX	Monroe, Wayne	64 min
Jul 21, 6:39 PM EDT	Severe Thunderstorm Warning	DTX	Saint Clair	31 min

Nearby

Severe Thunderstorm Warnings in Michigan, 1998 Every severe thunderstorm warning in 1998

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.