Alert archive / Minnesota / Dense Fog Advisories in 2021

Dense Fog Advisory 13, NWS Twin Cities, MN

December 15, 202142 counties in Minnesota; 9 counties in Wisconsin

NWS Twin Cities, MN issued this dense fog advisory at Dec 15, 2021, 3:34 AM CST for 42 counties in Minnesota; 9 counties in Wisconsin. It was in force for 11 hr.

The area

The counties it named.

The facts

Issued
Dec 15, 2021, 3:34 AM CST (09:34 UTC)
Expired
Dec 15, 2021, 3:00 PM CST
In force
11 hr
Issued by
NWS Twin Cities, MN
All 51 counties

Anoka County, MN, Benton County, MN, Blue Earth County, MN, Brown County, MN, Carver County, MN, Chippewa County, MN, Chisago County, MN, Dakota County, MN, Douglas County, MN, Faribault County, MN, Freeborn County, MN, Goodhue County, MN, Hennepin County, MN, Isanti County, MN, Kanabec County, MN, Kandiyohi County, MN, Lac qui Parle County, MN, Le Sueur County, MN, Martin County, MN, McLeod County, MN, Meeker County, MN, Mille Lacs County, MN, Morrison County, MN, Nicollet County, MN, Pope County, MN, Ramsey County, MN, Redwood County, MN, Renville County, MN, Rice County, MN, Scott County, MN, Sherburne County, MN, Sibley County, MN, Stearns County, MN, Steele County, MN, Stevens County, MN, Swift County, MN, Todd County, MN, Waseca County, MN, Washington County, MN, Watonwan County, MN, Wright County, MN, Yellow Medicine County, MN, Barron County, WI, Chippewa County, WI, Dunn County, WI, Eau Claire County, WI, Pepin County, WI, Pierce County, WI, Polk County, WI, Rusk County, WI, Saint Croix County, WI

The radar

The Minneapolis radar (KMPX), 20 km from the middle of the area, began a volume at 09:38 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

Minneapolis, MN (KMPX), launched 00:00Z, 9.6 hours before the alert went out and 17 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, Minneapolis, MN at 00:00Z on 2021-12-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 00:00Z on 2021-12-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 337 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
803 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
337 m²/s²
0-3 km storm-relative helicity
309 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

394 
WWUS73 KMPX 150934
NPWMPX

URGENT - WEATHER MESSAGE
National Weather Service Twin Cities/Chanhassen MN
334 AM CST Wed Dec 15 2021

...POTENTIALLY HISTORIC HIGH WIND EVENT TONIGHT...

.A very powerful low pressure system will track through later today
and this evening. Damaging winds with gusts of 60 to 65 mph are 
likely across all of the Upper Mississippi River Valley tonight. 
In addition, a line of severe thunderstorms will develop along a 
very fast moving cold front early this evening. This line of 
thunderstorms could contain gusts in excess of 80 mph and some 
embedded tornadoes across southern and eastern Minnesota into 
western Wisconsin. 

MNZ051>053-061-WIZ014>016-151815-
/O.NEW.KMPX.FG.Y.0013.211215T1200Z-211215T1800Z/
/O.EXT.KMPX.HW.W.0001.211216T0300Z-211216T1200Z/
Sherburne-Isanti-Chisago-Anoka-Polk-Barron-Rusk-
Including the cities of Elk River, Cambridge, Center City, 
Blaine, Osceola, Rice Lake, and Ladysmith
334 AM CST Wed Dec 15 2021

...DENSE FOG ADVISORY IN EFFECT UNTIL NOON CST TODAY...
...HIGH WIND WARNING NOW IN EFFECT FROM 9 PM THIS EVENING TO 6 AM
CST THURSDAY...

* WHAT...For the High Wind Warning, southwest winds 30 to 40 mph 
  with gusts up to 60 mph expected. For the Dense Fog Advisory, 
  visibility one quarter mile or less in dense fog.

* WHERE...In Wisconsin, Polk, Barron and Rusk Counties. In 
  Minnesota, Sherburne, Isanti, Chisago and Anoka Counties.

* WHEN...For the High Wind Warning, from 9 PM this evening to 6 
  AM CST Thursday. For the Dense Fog Advisory, until noon CST 
  today.

* IMPACTS...Damaging winds will blow down trees and power lines. 
  Widespread power outages are expected. Travel will be 
  difficult, especially for high profile vehicles. Hazardous 
  driving conditions due to low visibility.

* ADDITIONAL DETAILS...Widespread wind damage may also occur with
  a line of thunderstorms early this evening. Some wind gusts may
  exceed 80 mph.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

People should avoid being outside in forested areas and around
trees and branches. If possible, remain in the lower levels of
your home during the windstorm, and avoid windows. Use caution if
you must drive.

If driving, slow down, use your headlights, and leave plenty of
distance ahead of you.

&&

$$

MNZ044-045-049-050-151815-
/O.NEW.KMPX.FG.Y.0013.211215T1200Z-211215T1800Z/
/O.EXT.KMPX.HW.W.0001.211216T0300Z-211216T1200Z/
Mille Lacs-Kanabec-Stearns-Benton-
Including the cities of Princeton, Mora, St Cloud, 
and Sauk Rapids
334 AM CST Wed Dec 15 2021

...DENSE FOG ADVISORY IN EFFECT UNTIL NOON CST TODAY...
...HIGH WIND WARNING NOW IN EFFECT FROM 9 PM THIS EVENING TO 6 AM
CST THURSDAY...

* WHAT...For the High Wind Warning, west winds 30 to 40 mph with 
  gusts up to 60 mph expected. For the Dense Fog Advisory, 
  visibility one quarter mile or less in dense fog.

* WHERE...Mille Lacs, Kanabec, Stearns and Benton Counties.

* WHEN...For the High Wind Warning, from 9 PM this evening to 6 
  AM CST Thursday. For the Dense Fog Advisory, until noon CST 
  today.

* IMPACTS...Damaging winds will blow down trees and power lines.
  Widespread power outages are expected. Travel will be difficult,
  especially for high profile vehicles. Hazardous driving
  conditions due to low visibility.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

People should avoid being outside in forested areas and around
trees and branches. If possible, remain in the lower levels of
your home during the windstorm, and avoid windows. Use caution if
you must drive.

If driving, slow down, use your headlights, and leave plenty of
distance ahead of you.

&&

$$

MNZ042-043-151815-
/O.NEW.KMPX.FG.Y.0013.211215T1200Z-211215T2100Z/
/O.EXT.KMPX.HW.W.0001.211216T0300Z-211216T1200Z/
Todd-Morrison-
Including the cities of Long Prairie and Little Falls
334 AM CST Wed Dec 15 2021

...DENSE FOG ADVISORY IN EFFECT UNTIL 3 PM CST THIS AFTERNOON...
...HIGH WIND WARNING NOW IN EFFECT FROM 9 PM THIS EVENING TO 6 AM
CST THURSDAY...

* WHAT...For the High Wind Warning, west winds 30 to 40 mph with 
  gusts up to 60 mph expected. For the Dense Fog Advisory, 
  visibility one quarter mile or less in dense fog.

* WHERE...Todd and Morrison Counties.

* WHEN...For the High Wind Warning, from 9 PM this evening to 6 
  AM CST Thursday. For the Dense Fog Advisory, until 3 PM CST 
  this afternoon.

* IMPACTS...Damaging winds will blow down trees and power lines. 
  Widespread power outages are expected. Travel will be 
  difficult, especially for high profile vehicles. Hazardous 
  driving conditions due to low visibility.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

People should avoid being outside in forested areas and around
trees and branches. If possible, remain in the lower levels of
your home during the windstorm, and avoid windows. Use caution if
you must drive.

If driving, slow down, use your headlights, and leave plenty of
distance ahead of you.

&&

$$

MNZ082>085-091>093-151815-
/O.NEW.KMPX.FG.Y.0013.211215T0934Z-211215T1500Z/
/O.CON.KMPX.HW.W.0001.211216T0000Z-211216T1200Z/
Watonwan-Blue Earth-Waseca-Steele-Martin-Faribault-Freeborn-
Including the cities of St James, Mankato, Waseca, Owatonna, 
Fairmont, Blue Earth, and Albert Lea
334 AM CST Wed Dec 15 2021

...DENSE FOG ADVISORY IN EFFECT UNTIL 9 AM CST THIS MORNING...
...HIGH WIND WARNING REMAINS IN EFFECT FROM 6 PM THIS EVENING TO
6 AM CST THURSDAY...

* WHAT...For the High Wind Warning, southwest winds 30 to 40 mph 
  with gusts up to 65 mph expected. For the Dense Fog Advisory, 
  visibility less than one mile in dense fog.

* WHERE...Watonwan, Blue Earth, Waseca, Steele, Martin, 
  Faribault and Freeborn Counties.

* WHEN...For the High Wind Warning, from 6 PM this evening to 6 
  AM CST Thursday. For the Dense Fog Advisory, until 9 AM CST 
  this morning.

* IMPACTS...Damaging winds will blow down trees and power lines. 
  Widespread power outages are expected. Travel will be 
  difficult, especially for high profile vehicles. Hazardous 
  driving conditions due to low visibility.

* ADDITIONAL DETAILS...Widespread wind damage may also occur with
  a line of thunderstorms early this evening. Some wind gusts may
  exceed 80 mph.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

People should avoid being outside in forested areas and around
trees and branches. If possible, remain in the lower levels of
your home during the windstorm, and avoid windows. Use caution if
you must drive.

If driving, slow down, use your headlights, and leave plenty of
distance ahead of you.

&&

$$

MNZ058>060-062-063-065-066-068-WIZ023>028-151815-
/O.NEW.KMPX.FG.Y.0013.211215T1200Z-211215T1800Z/
/O.CON.KMPX.HW.W.0001.211216T0300Z-211216T1200Z/
Meeker-Wright-Hennepin-Ramsey-Washington-Renville-McLeod-Carver-
St. Croix-Pierce-Dunn-Pepin-Chippewa-Eau Claire-
Including the cities of Litchfield, Monticello, Minneapolis, 
St Paul, Stillwater, Olivia, Hutchinson, Chanhassen, Chaska, 
Victoria, Hudson, River Falls, Menomonie, Durand, Chippewa Falls,
and Eau Claire
334 AM CST Wed Dec 15 2021

...DENSE FOG ADVISORY IN EFFECT UNTIL NOON CST TODAY...
...HIGH WIND WARNING REMAINS IN EFFECT FROM 9 PM THIS EVENING TO
6 AM CST THURSDAY...

* WHAT...For the High Wind Warning, southwest winds 30 to 40 mph 
  with gusts up to 65 mph expected. For the Dense Fog Advisory, 
  visibility one quarter mile or less in dense fog.

* WHERE...Portions of west central Wisconsin and central and 
  east central Minnesota.

* WHEN...For the High Wind Warning, from 9 PM this evening to 6 
  AM CST Thursday. For the Dense Fog Advisory, until noon CST 
  today.

* IMPACTS...Damaging winds will blow down trees and power lines. 
  Widespread power outages are expected. Travel will be 
  difficult, especially for high profile vehicles. Hazardous 
  driving conditions due to low visibility.

* ADDITIONAL DETAILS...Widespread wind damage may also occur with
  a line of thunderstorms early this evening. Some wind gusts may
  exceed 80 mph.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

People should avoid being outside in forested areas and around
trees and branches. If possible, remain in the lower levels of
your home during the windstorm, and avoid windows. Use caution if
you must drive.

If driving, slow down, use your headlights, and leave plenty of
distance ahead of you.

&&

$$

MNZ067-069-070-073>078-151815-
/O.NEW.KMPX.FG.Y.0013.211215T0934Z-211215T1500Z/
/O.CON.KMPX.HW.W.0001.211216T0300Z-211216T1200Z/
Sibley-Scott-Dakota-Redwood-Brown-Nicollet-Le Sueur-Rice-Goodhue-
Including the cities of Gaylord, Shakopee, Hastings, 
Redwood Falls, New Ulm, St Peter, Le Sueur, Faribault, 
and Red Wing
334 AM CST Wed Dec 15 2021

...DENSE FOG ADVISORY IN EFFECT UNTIL 9 AM CST THIS MORNING...
...HIGH WIND WARNING REMAINS IN EFFECT FROM 9 PM THIS EVENING TO
6 AM CST THURSDAY...

* WHAT...For the High Wind Warning, west winds 30 to 40 mph with 
  gusts up to 65 mph expected. For the Dense Fog Advisory, 
  visibility one quarter to one half mile in dense fog.

* WHERE...Sibley, Scott, Dakota, Redwood, Brown, Nicollet, Le 
  Sueur, Rice and Goodhue Counties.

* WHEN...For the High Wind Warning, from 9 PM this evening to 6 
  AM CST Thursday. For the Dense Fog Advisory, until 9 AM CST 
  this morning.

* IMPACTS...Damaging winds will blow down trees and power lines. 
  Widespread power outages are expected. Travel will be 
  difficult, especially for high profile vehicles. Hazardous 
  driving conditions due to low visibility.

* ADDITIONAL DETAILS...Widespread wind damage may also occur with
  a line of thunderstorms early this evening. Some wind gusts may
  exceed 80 mph.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

People should avoid being outside in forested areas and around
trees and branches. If possible, remain in the lower levels of
your home during the windstorm, and avoid windows. Use caution if
you must drive.

If driving, slow down, use your headlights, and leave plenty of
distance ahead of you.

&&

$$

MNZ041-047-048-151815-
/O.NEW.KMPX.FG.Y.0013.211215T1200Z-211215T2100Z/
/O.CON.KMPX.HW.W.0001.211216T0300Z-211216T1200Z/
Douglas-Stevens-Pope-
Including the cities of Alexandria, Morris, and Glenwood
334 AM CST Wed Dec 15 2021

...DENSE FOG ADVISORY IN EFFECT UNTIL 3 PM CST THIS AFTERNOON...
...HIGH WIND WARNING REMAINS IN EFFECT FROM 9 PM THIS EVENING TO
6 AM CST THURSDAY...

* WHAT...For the High Wind Warning, northwest winds 30 to 40 mph 
  with gusts up to 60 mph expected. For the Dense Fog Advisory, 
  visibility one quarter mile or less in dense fog.

* WHERE...Douglas, Stevens and Pope Counties.

* WHEN...For the High Wind Warning, from 9 PM this evening to 6 
  AM CST Thursday. For the Dense Fog Advisory, until 3 PM CST 
  this afternoon.

* IMPACTS...Damaging winds will blow down trees and power lines.
  Widespread power outages are expected. Travel will be difficult,
  especially for high profile vehicles. Hazardous driving
  conditions due to low visibility.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

People should avoid being outside in forested areas and around
trees and branches. If possible, remain in the lower levels of
your home during the windstorm, and avoid windows. Use caution if
you must drive.

If driving, slow down, use your headlights, and leave plenty of
distance ahead of you.

&&

$$

MNZ054>057-064-151815-
/O.NEW.KMPX.FG.Y.0013.211215T1200Z-211215T1800Z/
/O.CON.KMPX.HW.W.0001.211216T0300Z-211216T1200Z/
Lac Qui Parle-Swift-Chippewa-Kandiyohi-Yellow Medicine-
Including the cities of Madison, Benson, Montevideo, Willmar, 
and Granite Falls
334 AM CST Wed Dec 15 2021

...DENSE FOG ADVISORY IN EFFECT UNTIL NOON CST TODAY...
...HIGH WIND WARNING REMAINS IN EFFECT FROM 9 PM THIS EVENING TO
6 AM CST THURSDAY...

* WHAT...For the High Wind Warning, west winds 30 to 40 mph with 
  gusts up to 60 mph expected. For the Dense Fog Advisory, 
  visibility one quarter mile or less in dense fog.

* WHERE...Lac Qui Parle, Swift, Chippewa, Kandiyohi and Yellow 
  Medicine Counties.

* WHEN...For the High Wind Warning, from 9 PM this evening to 6 
  AM CST Thursday. For the Dense Fog Advisory, until noon CST 
  today.

* IMPACTS...Damaging winds will blow down trees and power lines. 
  Widespread power outages are expected. Travel will be 
  difficult, especially for high profile vehicles. Hazardous 
  driving conditions due to low visibility.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

People should avoid being outside in forested areas and around
trees and branches. If possible, remain in the lower levels of
your home during the windstorm, and avoid windows. Use caution if
you must drive.

If driving, slow down, use your headlights, and leave plenty of
distance ahead of you.

&&

$$

Borghoff
1 follow-up statement
349 
WWUS73 KMPX 152125
NPWMPX

URGENT - WEATHER MESSAGE
National Weather Service Twin Cities/Chanhassen MN
325 PM CST Wed Dec 15 2021

MNZ041>043-047-048-161200-
/O.EXP.KMPX.FG.Y.0013.000000T0000Z-211215T2100Z/
/O.EXT.KMPX.HW.W.0001.211216T0000Z-211216T1200Z/
Douglas-Todd-Morrison-Stevens-Pope-
Including the cities of Alexandria, Long Prairie, Little Falls, 
Morris, and Glenwood
325 PM CST Wed Dec 15 2021

...DAMAGING WIND EVENT TONIGHT...

.A near-record strong low pressure system for December will impact
the region this evening through tonight. Damaging winds with 
gusts of 60 to 65 mph are likely across all of the Upper 
Mississippi River Valley tonight. In addition, a line of severe 
thunderstorms will develop along a very fast moving cold front 
early this evening. This line of thunderstorms could contain of 70
to 80 mph, as well as some embedded tornadoes across southern and
eastern Minnesota into western Wisconsin. 

...HIGH WIND WARNING NOW IN EFFECT UNTIL 6 AM CST THURSDAY...
...DENSE FOG ADVISORY HAS EXPIRED...

* WHAT...Northwest winds 25 to 35 mph with gusts up to 60 mph 
  expected.

* WHERE...Douglas, Stevens and Pope Counties.

* WHEN...Until 6 AM CST Thursday.

* IMPACTS...Damaging winds will blow down trees and power lines. 
  Widespread power outages are expected. Travel will be 
  difficult, especially for high profile vehicles.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

People should avoid being outside in forested areas and around
trees and branches. If possible, remain in the lower levels of
your home during the windstorm, and avoid windows. Use caution if
you must drive.

&&

$$

MNZ044-045-049>070-073>078-WIZ014>016-023>028-161200-
/O.EXT.KMPX.HW.W.0001.211216T0000Z-211216T1200Z/
Mille Lacs-Kanabec-Stearns-Benton-Sherburne-Isanti-Chisago-
Lac Qui Parle-Swift-Chippewa-Kandiyohi-Meeker-Wright-Hennepin-
Anoka-Ramsey-Washington-Yellow Medicine-Renville-McLeod-Sibley-
Carver-Scott-Dakota-Redwood-Brown-Nicollet-Le Sueur-Rice-Goodhue-
Polk-Barron-Rusk-St. Croix-Pierce-Dunn-Pepin-Eau Claire-
Including the cities of Princeton, Mora, St Cloud, Sauk Rapids, 
Elk River, Cambridge, Center City, Madison, Benson, Montevideo, 
Willmar, Litchfield, Monticello, Minneapolis, Blaine, St Paul, 
Stillwater, Granite Falls, Olivia, Hutchinson, Gaylord, 
Chanhassen, Chaska, Victoria, Shakopee, Hastings, Redwood Falls, 
New Ulm, St Peter, Le Sueur, Faribault, Red Wing, Osceola, 
Rice Lake, Ladysmith, Hudson, River Falls, Menomonie, Durand, 
Chippewa Falls, and Eau Claire
325 PM CST Wed Dec 15 2021

...HIGH WIND WARNING NOW IN EFFECT UNTIL 6 AM CST THURSDAY...

* WHAT...For the High Wind Warning, west winds 30 to 40 mph with 
  gusts up to 60 mph expected. For the Dense Fog Advisory, 
  visibility one quarter mile or less in dense fog.

* WHERE...Mille Lacs, Kanabec, Stearns and Benton Counties.

* WHEN...Until 6 AM CST Thursday.

* IMPACTS...Damaging winds will blow down trees and power lines. 
  Widespread power outages are expected. Travel will be 
  difficult, especially for high profile vehicles. Hazardous 
  driving conditions due to low visibility.

* ADDITIONAL DETAILS...Widespread wind damage may also occur with
  a line of thunderstorms early this evening. Wind gusts up to
  70-80 mph are possible.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

People should avoid being outside in forested areas and around
trees and branches. If possible, remain in the lower levels of
your home during the windstorm, and avoid windows. Use caution if
you must drive.

If driving, slow down, use your headlights, and leave plenty of
distance ahead of you.

&&

$$

MNZ082>085-091>093-161200-
/O.CON.KMPX.HW.W.0001.211216T0000Z-211216T1200Z/
Watonwan-Blue Earth-Waseca-Steele-Martin-Faribault-Freeborn-
Including the cities of St James, Mankato, Waseca, Owatonna, 
Fairmont, Blue Earth, and Albert Lea
325 PM CST Wed Dec 15 2021

...HIGH WIND WARNING REMAINS IN EFFECT UNTIL 6 AM CST THURSDAY...

* WHAT...For the High Wind Warning, southwest winds 30 to 40 mph 
  with gusts up to 65 mph expected. For the Dense Fog Advisory, 
  visibility less than one mile in dense fog.

* WHERE...Watonwan, Blue Earth, Waseca, Steele, Martin, 
  Faribault and Freeborn Counties.

* WHEN...For the High Wind Warning, from 6 PM this evening to 6 
  AM CST Thursday. For the Dense Fog Advisory, until 9 AM CST 
  this morning.

* IMPACTS...Damaging winds will blow down trees and power lines. 
  Widespread power outages are expected. Travel will be 
  difficult, especially for high profile vehicles. Hazardous 
  driving conditions due to low visibility.

* ADDITIONAL DETAILS...Widespread wind damage may also occur with
  a line of thunderstorms early this evening. Wind gusts up to
  70-80 mph are possible.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

People should avoid being outside in forested areas and around
trees and branches. If possible, remain in the lower levels of
your home during the windstorm, and avoid windows. Use caution if
you must drive.

If driving, slow down, use your headlights, and leave plenty of
distance ahead of you.

&&

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Dec 15, 3:28 AM CSTWinter Weather AdvisoryMPXBenton, Chippewa, Douglas, Kanabec, Kandiyohi, Lac qui Parle and 11 more31 hr
Dec 15, 3:38 PM CSTWinter Storm WarningMPXDouglas, Pope, Stevens, Todd18 hr
Dec 15, 5:25 PM CSTSevere Thunderstorm Warning Considerable damage threatMPXBlue Earth, Faribault, Martin, Watonwan35 min

Nearby

Dense Fog Advisories in Minnesota, 2021Dense Fog Advisories in Wisconsin, 2021Every dense fog advisory in 2021

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.