Alert archive / Michigan / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 49, NWS Detroit, MI

July 23, 1999Saint Clair County, Sanilac County, Michigan

NWS Detroit, MI issued this severe thunderstorm warning at Jul 23, 1999, 3:42 PM EDT for Saint Clair County, Sanilac County, Michigan. It was in force for 63 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 23, 1999, 3:42 PM EDT (19:42 UTC)
Expired
Jul 23, 1999, 4:45 PM EDT
In force
63 min
Issued by
NWS Detroit, MI
Area
Whole counties

Counties Saint Clair County, MI, Sanilac County, MI

The radar

The Detroit radar (KDTX), 86 km from the middle of the area, began a volume at 19:44 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

TimeReportWhereRemark
Jul 23, 4:00 PM EDTThunderstorm Wind 52Capac, MI
Jul 23, 4:40 PM EDTThunderstorm Wind 52Port Huron, MI
Jul 23, 4:50 PM EDTThunderstorm Wind 52Algonac, 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.

IssuedProductOfficeLasted
Jul 23, 12:30 PM EDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Detroit, MI (KDTX), launched 12:00Z, 7.7 hours before the alert went out and 82 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-pSkew-T log-p diagram, Detroit, MI at 12:00Z on 1999-07-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 28 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Detroit, MI at 12:00Z on 1999-07-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 73 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
28 J/kg
Mixed-layer CIN
-342 J/kg
Mixed-layer LCL
1152 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
73 m²/s²
0-3 km storm-relative helicity
41 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.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 23, 12:58 PM EDTSevere Thunderstorm WarningDTXMidland62 min
Jul 23, 2:21 PM EDTSevere Thunderstorm WarningDTXSaginaw59 min
Jul 23, 2:48 PM EDTSevere Thunderstorm WarningDTXShiawassee62 min
Jul 23, 2:54 PM EDTSevere Thunderstorm WarningDTXTuscola76 min
Jul 23, 2:57 PM EDTSevere Thunderstorm WarningDTXGenesee63 min
Jul 23, 3:12 PM EDTSevere Thunderstorm WarningDTXLivingston63 min
Jul 23, 3:17 PM EDTSevere Thunderstorm WarningDTXLapeer63 min
Jul 23, 3:37 PM EDTSevere Thunderstorm WarningDTXOakland63 min
Jul 23, 3:38 PM EDTSevere Thunderstorm WarningDTXWashtenaw52 min
Jul 23, 3:53 PM EDTSevere Thunderstorm WarningDTXMacomb77 min
Jul 23, 4:06 PM EDTSevere Thunderstorm WarningDTXWayne64 min
Jul 23, 4:41 PM EDTSevere Thunderstorm WarningDTXOakland19 min
Jul 23, 4:43 PM EDTSevere Thunderstorm WarningDTXSaint Clair47 min
Jul 23, 5:56 PM EDTSevere Thunderstorm WarningDTXLenawee64 min

Nearby

Severe Thunderstorm Warnings in Michigan, 1999Every severe thunderstorm warning in 1999

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.