Alert archive / Minnesota / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 71, NWS Duluth, MN

July 17, 2017Cass County, Crow Wing County, Minnesota

NWS Duluth, MN issued this severe thunderstorm warning at Jul 17, 2017, 5:05 PM CDT for Cass County, Crow Wing County, Minnesota. It was in force for 40 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 17, 2017, 5:05 PM CDT (22:05 UTC)
Expired: Jul 17, 2017, 5:45 PM CDT
In force: 40 min
Issued by: NWS Duluth, MN
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Cass County, MN, Crow Wing County, MN

The radar

The Duluth radar (KDLH), 152 km from the middle of the area, began a volume at 22:08 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Jul 17, 3:21 PM CDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 10.1 hours before the alert went out and 213 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: 1041 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 140 m²/s²
0-3 km storm-relative helicity: 214 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 Duluth, MN wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 17, 3:35 PM CDT, 1 hour 30 minutes earlier.

Area forecast discussion, Jul 17, 3:35 PM CDT, 1 hour 30 minutes before

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<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.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

Hazardous weather outlook, Jul 17, 3:43 PM CDT, 1 hour 22 minutes before

Hazardous Weather Outlook
National Weather Service Duluth MN
343 PM CDT Mon Jul 17 2017

MNZ010>012-018>021-025-026-033>038-WIZ001>004-006>009-181245-
Koochiching-North St. Louis-Northern Cook/Northern Lake-
North Itasca-Central St. Louis-Southern Lake/North Shore-
Southern Cook/North Shore-North Cass-South Itasca-South Cass-
Crow Wing-Northern Aitkin-South Aitkin-Carlton/South St. Louis-
Pine-Douglas-Bayfield-Ashland-Iron-Burnett-Washburn-Sawyer-Price-
343 PM CDT Mon Jul 17 2017

This Hazardous Weather Outlook is for portions of northeast
Minnesota and northwest Wisconsin.

.DAY ONE...This afternoon and Tonight

Strong to severe thunderstorms are expected to develop across
north-central Minnesota later this afternoon and track eastward
into northeast Minnesota towards this evening. The strongest
storms will be capable of producing large hail and damaging winds,
with a small chance of a tornado. A Severe Thunderstorm Watch has
been issued for all of north-central and northeast Minnesota, as
well as portions of northwest Wisconsin for this afternoon and
evening.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

Another round of strong to severe thunderstorms are expected
Tuesday, mainly for east central Minnesota into northwest
Wisconsin.

Thunderstorms are possible from central Minnesota to northwest
Wisconsin Wednesday afternoon through Thursday morning.

Thunderstorms are possible across northeast Minnesota and
northwest Wisconsin Friday afternoon, and again Saturday
afternoon through Saturday night.

.SPOTTER INFORMATION STATEMENT...

Skywarn Spotters will be needed this afternoon into this evening
across much of north-central and northeast Minnesota and portions
of northwest Wisconsin. Please report hail of any size, damaging
winds, and heavy rainfall amounts.

LSZ121-140>148-181245-
Bayfield to Oak Point WI-Grand Portage to Grand Marais MN-
Grand Marais to Taconite Harbor MN-
Taconite Harbor to Silver Bay Harbor MN-
Silver Bay Harbor to Two Harbors MN-Two Harbors to Duluth MN-
Duluth MN to Port Wing WI-Port Wing to Sand Island WI-
Sand Island to Bayfield WI-Oak Point to Saxon Harbor WI-
343 PM CDT Mon Jul 17 2017

This Hazardous Weather Outlook is for portions of the Nearshore
waters of western Lake Superior.

.DAY ONE...This afternoon and Tonight

Strong to severe thunderstorms will be possible over the western
Lake Superior nearshore waters later this evening and overnight.
Some storms may cause damaging winds, large hail, cloud-to-water
lightning, and heavy downpours.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

Thunderstorms will be possible during the day Tuesday.

Another chance of thunderstorms will be possible Saturday
afternoon through Sunday morning.

JTS

More information may be obtained at the following web address:
http://www.weather.gov/duluth (all lower case)

In the hours before

Special weather statement, Jul 17, 12:10 PM CDT, 4 hours 55 minutes before

Special Weather Statement
National Weather Service Duluth MN
1210 PM CDT MON JUL 17 2017

MNZ018-171730-
North Itasca-
1210 PM CDT MON JUL 17 2017

...A STRONG THUNDERSTORM WILL AFFECT NORTHWESTERN ITASCA COUNTY...

At 1210 PM CDT, a strong thunderstorm was near Alvwood, or 36 miles
northeast of Bemidji, moving northeast at 40 mph.

Wind gusts up to 40 mph and dime-size hail can be expected with this
storm.

This storm will remain over mainly rural areas of northwestern North
Itasca County.

Seek shelter inside a sturdy building and away from windows until
this storm passes.

LAT...LON 4768 9423 4775 9428 4785 9402 4774 9396
TIME...MOT...LOC 1710Z 243DEG 36KT 4774 9419

Mokry

Special weather statement, Jul 17, 1:49 PM CDT, 3 hours 16 minutes before

Special Weather Statement
National Weather Service Duluth MN
149 PM CDT MON JUL 17 2017

MNZ011-012-019-171900-
Northern Cook/Northern Lake-Central St. Louis-North St. Louis-
149 PM CDT MON JUL 17 2017

...A LINE OF STRONG THUNDERSTORMS WILL AFFECT CENTRAL ST. LOUIS AND
NORTHWESTERN LAKE COUNTIES...

At 149 PM CDT, a cluster thunderstorms were along a line extending
from 13 miles northwest of Alpine Lake, to 11 miles southeast of
Togo, and moving northeast at 50 mph.

Wind gusts up to 45 mph and occasional cloud to ground lightning can
be expected with these storms.

These storms will remain over mainly rural areas of northwestern
Northern Cook/Northern Lake...northern Central St. Louis and
southeastern North St. Louis Counties, including the following
locations: Ensign Lake, Shermans Corner, Side Lake, Ojibway Lake,
Perch Lake, Farm Lake, Soudan, Angora, Bear Head Lake and
Disappointment Lake.

Seek shelter inside a sturdy building and away from windows until
these storms pass.

If you are on or near any area lakes, get off the water and seek
shelter inside a sturdy building or a hard-topped vehicle. Remember,
lightning can strike 10 miles away from a thunderstorm. If you can
hear thunder, you are close enough to be struck by lightning.

LAT...LON 4812 9171 4812 9168 4811 9168 4811 9166
      4810 9164 4811 9156 4804 9157 4807 9150
      4805 9143 4808 9127 4803 9126 4797 9121
      4780 9187 4771 9237 4764 9306 4792 9272
      4813 9222 4820 9172
TIME...MOT...LOC 1847Z 247DEG 44KT 4827 9122 4768 9302

Mokry

Special weather statement, Jul 17, 2:08 PM CDT, 2 hours 57 minutes before

Special Weather Statement
National Weather Service Duluth MN
208 PM CDT MON JUL 17 2017

MNZ011-012-171945-
Northern Cook/Northern Lake-North St. Louis-
208 PM CDT MON JUL 17 2017

...AN AREA OF THUNDERSTORMS WILL AFFECT WEST CENTRAL COOK...EAST
CENTRAL ST. LOUIS AND NORTHERN LAKE COUNTIES...

At 208 PM CDT, an area of thunderstorms was over western Boundary
Waters Canoe Area Wilderness, or 17 miles northeast of Ely, moving
east at 65 mph.

Wind gusts up to 40 mph can be expected with these storms.

these storms will remain over mainly rural areas of northwestern
Northern Cook/Northern Lake and east central North St. Louis
Counties, including the following locations: Ensign Lake, Hudson
Lake, Kekekabic Lake, Bald Eagle Lake, Gabbro Lake, Alice Lake,
Thomas Lake, Knife Lake, Ojibway Lake and Farm Lake.

Seek shelter inside a sturdy building and away from windows until
these storms pass.

If you are on or near any area lakes in the Boundary Waters Canoe
Area, get off the water and seek shelter inside a sturdy building or
a hard-topped vehicle. Remember, lightning can strike 10 miles away
from a thunderstorm. If you can hear thunder, you are close enough
to be struck by lightning.

LAT...LON 4820 9179 4820 9173 4817 9172 4817 9170
      4811 9171 4812 9168 4810 9164 4811 9156
      4804 9157 4807 9150 4807 9145 4805 9143
      4808 9125 4818 9109 4798 9087 4775 9171
      4815 9201 4821 9181
TIME...MOT...LOC 1908Z 257DEG 59KT 4810 9159

Mokry

Special weather statement, Jul 17, 2:47 PM CDT, 2 hours 18 minutes before

Special Weather Statement
National Weather Service Duluth MN
247 PM CDT MON JUL 17 2017

MNZ012-172015-
Northern Cook/Northern Lake-
247 PM CDT MON JUL 17 2017

...AN AREA OF THUNDERSTORMS WILL AFFECT NORTHWESTERN COOK AND
NORTHEASTERN LAKE COUNTIES...

At 246 PM CDT, an area of thunderstorms was over southeastern
Boundary Waters Canoe Area Wilderness, or 19 miles southwest of
Saganaga Lake, moving east at 45 mph.

Wind gusts up to 40 mph and occasional cloud to ground lightning can
be expected with these storms.

These storms will be near...
  Little Saganaga Lake and Alpine Lake around 300 PM CDT.
  Sea Gull Lake around 310 PM CDT.
  Gunflint Lake around 315 PM CDT.

Other locations impacted by these storms include Hudson Lake, Brule
Lake, Kekekabic Lake, Cherokee Lake, Alice Lake, Thomas Lake, Sawbill
Landing, Perent Lake, Isabella Lake, and Disappointment Lake.

Seek shelter inside a sturdy building and away from windows until
these storms pass.

If you are on or near one of the many area lakes, get off the water
immediately and seek shelter on shore inside a sturdy building or a
hard-topped vehicle. If possible, stay away from trees.

LAT...LON 4811 9077 4809 9075 4810 9071 4803 9049
      4767 9125 4783 9149 4807 9133 4808 9125
      4819 9105
TIME...MOT...LOC 1946Z 249DEG 40KT 4799 9118

Mokry

Special weather statement, Jul 17, 4:31 PM CDT, 34 minutes before

Special Weather Statement
National Weather Service Duluth MN
431 PM CDT MON JUL 17 2017

MNZ033-172200-
South Cass-
431 PM CDT MON JUL 17 2017

...AN AREA OF STRONG THUNDERSTORMS WILL AFFECT SOUTHWESTERN CASS
COUNTY...

At 431 PM CDT, an area of strong thunderstorms was 9 miles southeast
of Sebeka, or 37 miles northwest of Brainerd, moving east at 25 mph.

Wind gusts up to 45 mph, penny-size hail, heavy downpours, and
frequent cloud to ground lightning can be expected with these storms.

Locations impacted include...
Pine River, Pillager, Poplar, Leader, Gull Lake, Sylvan, Lake Shore,
East Gull Lake, Jenkins, Chickamaw Beach, Casino, and Esterdy.

Seek shelter inside a sturdy building and away from windows until
these storms pass.

These storms may intensify, please monitor local media outlets for
additional information and possible warnings from the National
Weather Service.

LAT...LON 4675 9478 4677 9434 4628 9434 4630 9436
      4630 9439 4633 9443 4633 9446 4630 9454
      4633 9460 4633 9462 4636 9467 4635 9468
      4635 9472 4638 9473 4638 9476 4639 9478
TIME...MOT...LOC 2131Z 270DEG 23KT 4657 9492

DAP

Special weather statement, Jul 17, 4:56 PM CDT, 9 minutes before

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<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.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

The office that day

Everything else NWS Duluth, MN issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 17, 11:54 AM CDT	Special Weather Statement	DLH	Itasca	21 min
Jul 17, 12:10 PM CDT	Special Weather Statement	DLH	Itasca	20 min
Jul 17, 1:49 PM CDT	Special Weather Statement	DLH	Saint Louis	11 min
Jul 17, 2:08 PM CDT	Special Weather Statement	DLH	Lake	37 min
Jul 17, 2:47 PM CDT	Special Weather Statement	DLH	Cook	28 min
Jul 17, 4:31 PM CDT	Special Weather Statement	DLH	Wadena	29 min
Jul 17, 4:44 PM CDT	Severe Thunderstorm Warning	DLH	Cass	31 min
Jul 17, 4:56 PM CDT	Special Weather Statement	DLH	Aitkin	34 min
Jul 17, 5:31 PM CDT	Special Weather Statement	DLH	Crow Wing	29 min
Jul 17, 5:34 PM CDT	Severe Thunderstorm Warning	DLH	Crow Wing	41 min
Jul 17, 5:43 PM CDT	Special Weather Statement	DLH	Aitkin	17 min
Jul 17, 5:56 PM CDT	Severe Thunderstorm Warning	DLH	Itasca	49 min
Jul 17, 5:58 PM CDT	Severe Thunderstorm Warning	DLH	Aitkin, Cass, Crow Wing	47 min
Jul 17, 6:01 PM CDT	Severe Thunderstorm Warning	DLH	Cass, Itasca	44 min
Jul 17, 6:09 PM CDT	Severe Thunderstorm Warning	DLH	Crow Wing	39 min
Jul 17, 6:10 PM CDT	Special Weather Statement	DLH	Itasca	20 min
Jul 17, 6:34 PM CDT	Special Weather Statement	DLH	Carlton	86 min
Jul 17, 6:38 PM CDT	Special Weather Statement	DLH	Saint Louis	37 min
Jul 17, 6:42 PM CDT	Special Weather Statement	DLH	Saint Louis	33 min
Jul 17, 6:43 PM CDT	Severe Thunderstorm Warning	DLH	Aitkin, Carlton, Pine, Saint Louis	62 min
Jul 17, 6:46 PM CDT	Special Weather Statement	DLH	Itasca	29 min
Jul 17, 6:53 PM CDT	Severe Thunderstorm Warning	DLH	Saint Louis	37 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 2017 Every severe thunderstorm warning in 2017

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.