Alert archive / Michigan / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 59, NWS Detroit, MI

August 18, 2019Saint Clair County, Michigan

NWS Detroit, MI issued this severe thunderstorm warning at Aug 18, 2019, 2:03 PM EDT for Saint Clair County, Michigan. It was in force for 28 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
Aug 18, 2019, 2:03 PM EDT (18:03 UTC)
Expired
Aug 18, 2019, 2:31 PM EDT
In force
28 min
Issued by
NWS Detroit, MI
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

County Saint Clair County, MI

The radar

The Detroit radar (KDTX), 71 km from the middle of the area, began a volume at 18:05 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

Detroit, MI (KDTX), launched 12:00Z, 6.1 hours before the alert went out and 67 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 2019-08-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 453 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 2019-08-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 106 square meters per square second.19395878Sfc1 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
453 J/kg
Mixed-layer CIN
-45 J/kg
Mixed-layer LCL
727 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
106 m²/s²
0-3 km storm-relative helicity
101 m²/s²
Significant tornado parameter
0.1
Supercell composite
1.9

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 Detroit, MI wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 18, 1:44 PM EDT, 19 minutes earlier.

Area forecast discussion, Aug 18, 1:44 PM EDT, 19 minutes before
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Hazardous weather outlook, Aug 18, 1:00 PM EDT, 1 hour 3 minutes before
Hazardous Weather Outlook
National Weather Service Detroit/Pontiac MI
100 PM EDT Sun Aug 18 2019

MIZ047>049-053>055-060>063-068>070-075-076-082-083-190800-
Midland-Bay-Huron-Saginaw-Tuscola-Sanilac-Shiawassee-Genesee-Lapeer-
St. Clair-Livingston-Oakland-Macomb-Washtenaw-Wayne-Lenawee-Monroe-
100 PM EDT Sun Aug 18 2019

This hazardous weather outlook is for southeast Michigan.

.DAY ONE...Today and Tonight

Scattered to numerous thunderstorms are moving through southeast
Michigan this afternoon. Isolated severe thunderstorms are expected,
producing damaging winds at or above 60 mph and hail to around one
in diameter. A second line of thunderstorms is possible by early
evening (5-8 PM), and remains a low chance this activity may be
severe as well, but confidence is not high. All thunderstorms will
also produce brief yet intense rainfall rates as they move east at
40 mph.

.DAYS TWO THROUGH SEVEN...Monday through Saturday

There is a chance of thunderstorms on Wednesday as a cold front is
forecast to move across the region.

.SPOTTER INFORMATION STATEMENT...

Dispatchers...please notify your emergency managers immediately.
Spotter activation may be needed this afternoon.

LCZ460-LEZ444-LHZ361>363-421-422-441>443-462>464-190800-
Lake St Clair-
Michigan Waters of Lake Erie from Detroit River to North Cape MI-
Lake Huron from 5NM east of Mackinac Bridge to Presque Isle Lt
beyond 5 NM off shore-
Lake Huron from Presque Isle Light to Sturgeon Point MI beyond 5NM
off shore-
Lake Huron from Sturgeon Point to Alabaster MI beyond 5NM off shore-
Outer Saginaw Bay SW of Alabaster to Port Austin MI to Inner Saginaw
Bay-Inner Saginaw Bay SW of Point Au Gres to Bay Port MI-
Port Austin to Harbor Beach MI-Harbor Beach to Port Sanilac MI-
Port Sanilac to Port Huron MI-
Lake Huron from Port Austin to Harbor Beach beyond 5NM Off Shore-
Lake Huron from Harbor Beach to Port Sanilac beyond 5NM Off Shore-
Lake Huron from Port Sanilac to Port Huron beyond 5NM Off Shore-
100 PM EDT Sun Aug 18 2019

This hazardous weather outlook is for portions of Lake Erie, Lake
Huron and Lake St Clair.

.DAY ONE...Today and Tonight

Scattered to numerous thunderstorms are expected this afternoon and
early this evening. There is a slight risk of severe weather. The
strongest storms will be capable of wind gusts to 50 knots and hail
to one inch in diameter as they move to the east at 35 knots. All
thunderstorms will also produce brief yet intense rainfall rates.

.DAYS TWO THROUGH SEVEN...Monday through Saturday

There is a chance of thunderstorms on Wednesday as a cold front is
forecast to move across the region.

.SPOTTER INFORMATION STATEMENT...

Dispatchers...please notify your emergency managers immediately.
Spotter activation may be needed this afternoon.

You can obtain your latest National Weather Service forecasts online
at www.weather.gov/detroit.

Sf

In the hours before

Special weather statement, Aug 18, 12:37 PM EDT, 1 hour 26 minutes before
Special Weather Statement
National Weather Service Detroit/Pontiac MI
1237 PM EDT Sun Aug 18 2019

MIZ082-181730-
Lenawee MI-
1237 PM EDT Sun Aug 18 2019

...SPECIAL WEATHER STATEMENT...

At 1235 PM EDT, Doppler radar was tracking strong thunderstorms near
Clinton, or 7 miles south of Manchester, moving east at 40 mph.

One quarter inch hail and winds in excess of 30 mph will be possible
with these storms.

This strong thunderstorm will be near...
  Tecumseh around 1245 PM EDT.
  Milan around 105 PM EDT.
  Romulus and Flat Rock around 130 PM EDT.

Other locations impacted by this storm include Manitou Beach-Devils
Lake, Whittaker, Gibraltar, Ogden Center, Canandaigua, New Boston,
Ridgeway, Palmyra, Sand Creek and Medina.

LAT...LON 4207 8436 4208 8377 4238 8288 4229 8309
      4224 8313 4208 8314 4207 8377 4172 8377
      4171 8436
TIME...MOT...LOC 1635Z 254DEG 36KT 4205 8407

AA
Special weather statement, Aug 18, 1:16 PM EDT, 47 minutes before
Special Weather Statement
National Weather Service Detroit/Pontiac MI
116 PM EDT Sun Aug 18 2019

MIZ083-181815-
Monroe MI-
116 PM EDT Sun Aug 18 2019

...SIGNIFICANT WEATHER ADVISORY FOR MONROE COUNTY UNTIL 215 PM EDT...

At 114 PM EDT, Doppler radar was tracking a cluster of strong
thunderstorms over Ida, or near Dundee, moving east at 40 mph.

Half inch hail and winds in excess of 40 mph will be possible with
this storm.

Other locations impacted by this storm include Newport, Cone, Estral
Beach, Toledo Beach, Erie, South Rockwood, Woodland Beach, Stony
Point, Bolles Harbor and Samaria.

LAT...LON 4208 8377 4209 8329 4203 8319 4208 8319
      4209 8313 4204 8315 4201 8313 4190 8325
      4190 8330 4187 8338 4176 8343 4178 8346
      4175 8346 4175 8343 4174 8343 4172 8376
TIME...MOT...LOC 1714Z 255DEG 38KT 4195 8357

AA
Special weather statement, Aug 18, 1:16 PM EDT, 47 minutes before
Special Weather Statement
National Weather Service Detroit/Pontiac MI
116 PM EDT Sun Aug 18 2019

MIZ069-070-181800-
Macomb MI-Oakland MI-
116 PM EDT Sun Aug 18 2019

...SPECIAL WEATHER STATEMENT...

At 116 PM EDT, Doppler radar was tracking a rapidly developing
thunderstorm near Troy, moving east at 35 mph.

Pea size hail and winds in excess of 30 mph will be possible with
this storm.

This strong thunderstorm will be near...
  Warren and Rochester around 125 PM EDT.
  Sterling Heights and Clinton around 135 PM EDT.
  Mount Clemens and Macomb Township around 140 PM EDT.
  New Baltimore around 155 PM EDT.

Other locations impacted by this storm include Rochester Hills,
Shelby Township, Clawson, Ray Center, Fraser, Utica, Washington,
Bloomfield Hills, New Haven and Stoney Creek Metro Park.

People attending Jimmy John's Field should prepare to seek safe
shelter.

LAT...LON 4252 8273 4254 8276 4254 8281 4252 8282
      4253 8330 4264 8332 4289 8274 4273 8273
      4270 8272 4252 8270
TIME...MOT...LOC 1716Z 256DEG 31KT 4261 8319

Mann
Special weather statement, Aug 18, 1:18 PM EDT, 45 minutes before
Special Weather Statement
National Weather Service Detroit/Pontiac MI
118 PM EDT Sun Aug 18 2019

MIZ061-062-181800-
Genesee MI-Lapeer MI-
118 PM EDT Sun Aug 18 2019

...SPECIAL WEATHER STATEMENT...

At 117 PM EDT, Doppler radar was tracking a strong thunderstorm over
Lapeer, moving northeast at 45 mph.

Pea size hail and winds in excess of 30 mph will be possible with
this storm.

This strong thunderstorm will be near...
  Imlay City and Lum around 135 PM EDT.
  North Branch around 140 PM EDT.
  Brown City around 145 PM EDT.

Other locations impacted by this storm include Goodland Township,
Burnside, Kings Mill, Attica, Elba and Thornville.

People attending Lapeer Days Festival should prepare to seek safe
shelter.

LAT...LON 4291 8346 4319 8358 4329 8306 4328 8300
      4297 8299
TIME...MOT...LOC 1717Z 239DEG 38KT 4304 8336

Mann
Local storm report, Aug 18, 1:49 PM EDT, 14 minutes before
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Special weather statement, Aug 18, 2:00 PM EDT, 3 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
Aug 18, 3:39 AM EDTSmall Craft AdvisoryDTX19 hr
Aug 18, 12:37 PM EDTSpecial Weather StatementDTXLenawee53 min
Aug 18, 12:54 PM EDTSpecial Marine WarningDTX81 min
Aug 18, 12:55 PM EDTSevere Thunderstorm WarningDTXMonroe, Washtenaw, Wayne54 min
Aug 18, 1:04 PM EDTSpecial Marine WarningDTX86 min
Aug 18, 1:16 PM EDTSpecial Weather StatementDTXMacomb44 min
Aug 18, 1:18 PM EDTSpecial Weather StatementDTXLapeer42 min
Aug 18, 1:47 PM EDTSpecial Marine WarningDTX58 min
Aug 18, 1:49 PM EDTSevere Thunderstorm WarningDTXLapeer, Sanilac56 min
Aug 18, 2:00 PM EDTSpecial Weather StatementDTXMacomb60 min
Aug 18, 2:07 PM EDTSpecial Marine WarningDTX83 min
Aug 18, 2:16 PM EDTSpecial Marine WarningDTX29 min
Aug 18, 7:03 PM EDTSpecial Weather StatementDTXMacomb, Oakland, Saint Clair57 min
Aug 18, 7:06 PM EDTSpecial Weather StatementDTXLivingston, Washtenaw54 min
Aug 18, 7:12 PM EDTSevere Thunderstorm WarningDTXLivingston, Washtenaw63 min
Aug 18, 7:44 PM EDTSevere Thunderstorm WarningDTXOakland47 min
Aug 18, 7:52 PM EDTSpecial Weather StatementDTXLenawee53 min

Nearby

Severe Thunderstorm Warnings in Michigan, 2019Every 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; radar from the NEXRAD Level II archive.