Alert archive / Minnesota / Frost Advisories in 2020

Frost Advisory 2, NWS Twin Cities, MN

September 10, 202011 counties in Minnesota; 9 counties in Wisconsin

NWS Twin Cities, MN issued this frost advisory at Sep 10, 2020, 2:44 PM CDT for 11 counties in Minnesota; 9 counties in Wisconsin. It took effect at Sep 10, 2020, 11:00 PM CDT. It was in force for 10 hr.

The area

The counties it named.

The facts

Issued
Sep 10, 2020, 2:44 PM CDT (19:44 UTC)
In effect from
Sep 10, 2020, 11:00 PM CDT
Expired
Sep 11, 2020, 9:00 AM CDT
In force
10 hr
Issued by
NWS Twin Cities, MN

Counties Anoka County, MN, Benton County, MN, Chisago County, MN, Isanti County, MN, Kanabec County, MN, Mille Lacs County, MN, Morrison County, MN, Sherburne County, MN, Stearns County, MN, Todd County, MN, Washington 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), 79 km from the middle of the area, began a volume at 19:46 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 12:00Z, 7.7 hours before the alert went out and 80 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 12:00Z on 2020-09-10Temperature 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 12:00Z on 2020-09-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -24 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
848 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
-24 m²/s²
0-3 km storm-relative helicity
54 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

777 
WWUS73 KMPX 101944
NPWMPX

URGENT - WEATHER MESSAGE
National Weather Service Twin Cities/Chanhassen MN
244 PM CDT Thu Sep 10 2020

MNZ042>045-049>053-061-063-WIZ014>016-023>028-110345-
/O.NEW.KMPX.FR.Y.0002.200911T0400Z-200911T1400Z/
Todd-Morrison-Mille Lacs-Kanabec-Stearns-Benton-Sherburne-Isanti-
Chisago-Anoka-Washington-Polk-Barron-Rusk-St. Croix-Pierce-Dunn-
Pepin-Chippewa-Eau Claire-
Including the cities of Long Prairie, Little Falls, Princeton, 
Mora, St Cloud, Sauk Rapids, Elk River, Cambridge, Center City, 
Blaine, Stillwater, Osceola, Rice Lake, Ladysmith, Hudson, 
River Falls, Menomonie, Durand, Chippewa Falls, and Eau Claire
244 PM CDT Thu Sep 10 2020

...FROST ADVISORY IN EFFECT FROM 11 PM THIS EVENING TO 9 AM CDT
FRIDAY...

* WHAT...Temperatures as low as 33 will result in frost 
  formation.

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

* WHEN...From 11 PM this evening to 9 AM CDT Friday.

* IMPACTS...Frost could kill sensitive outdoor vegetation if 
  left uncovered.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

&&

$$
3 follow-up statements
366 
WWUS73 KMPX 110229
NPWMPX

URGENT - WEATHER MESSAGE
National Weather Service Twin Cities/Chanhassen MN
929 PM CDT Thu Sep 10 2020

MNZ042>045-049>053-061-063-WIZ014>016-023>028-111030-
/O.CON.KMPX.FR.Y.0002.200911T0400Z-200911T1400Z/
Todd-Morrison-Mille Lacs-Kanabec-Stearns-Benton-Sherburne-Isanti-
Chisago-Anoka-Washington-Polk-Barron-Rusk-St. Croix-Pierce-Dunn-
Pepin-Chippewa-Eau Claire-
Including the cities of Long Prairie, Little Falls, Princeton, 
Mora, St Cloud, Sauk Rapids, Elk River, Cambridge, Center City, 
Blaine, Stillwater, Osceola, Rice Lake, Ladysmith, Hudson, 
River Falls, Menomonie, Durand, Chippewa Falls, and Eau Claire
929 PM CDT Thu Sep 10 2020

...FROST ADVISORY REMAINS IN EFFECT UNTIL 9 AM CDT FRIDAY...

* WHAT...Temperatures as low as 33 will result in frost 
  formation.

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

* WHEN...From 11 PM this evening to 9 AM CDT Friday.

* IMPACTS...Frost could kill sensitive outdoor vegetation if 
  left uncovered.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

&&

$$
592 
WWUS73 KMPX 110911
NPWMPX

URGENT - WEATHER MESSAGE
National Weather Service Twin Cities/Chanhassen MN
411 AM CDT Fri Sep 11 2020

MNZ042>045-049>053-061-063-WIZ014>016-023>028-111400-
/O.CON.KMPX.FR.Y.0002.000000T0000Z-200911T1400Z/
Todd-Morrison-Mille Lacs-Kanabec-Stearns-Benton-Sherburne-Isanti-
Chisago-Anoka-Washington-Polk-Barron-Rusk-St. Croix-Pierce-Dunn-
Pepin-Chippewa-Eau Claire-
Including the cities of Long Prairie, Little Falls, Princeton, 
Mora, St Cloud, Sauk Rapids, Elk River, Cambridge, Center City, 
Blaine, Stillwater, Osceola, Rice Lake, Ladysmith, Hudson, 
River Falls, Menomonie, Durand, Chippewa Falls, and Eau Claire
411 AM CDT Fri Sep 11 2020

...FROST ADVISORY REMAINS IN EFFECT UNTIL 9 AM CDT THIS MORNING...

* WHAT...Temperatures as low as 33 will result in frost 
  formation.

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

* WHEN...Until 9 AM CDT Friday.

* IMPACTS...Frost could kill sensitive outdoor vegetation if 
  left uncovered.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

&&

$$
853 
WWUS73 KMPX 111403
NPWMPX

URGENT - WEATHER MESSAGE
National Weather Service Twin Cities/Chanhassen MN
903 AM CDT Fri Sep 11 2020

MNZ042>045-049>053-061-063-WIZ014>016-023>028-111515-
/O.EXP.KMPX.FR.Y.0002.000000T0000Z-200911T1400Z/
Todd-Morrison-Mille Lacs-Kanabec-Stearns-Benton-Sherburne-Isanti-
Chisago-Anoka-Washington-Polk-Barron-Rusk-St. Croix-Pierce-Dunn-
Pepin-Chippewa-Eau Claire-
Including the cities of Long Prairie, Little Falls, Princeton, 
Mora, St Cloud, Sauk Rapids, Elk River, Cambridge, Center City, 
Blaine, Stillwater, Osceola, Rice Lake, Ladysmith, Hudson, 
River Falls, Menomonie, Durand, Chippewa Falls, and Eau Claire
903 AM CDT Fri Sep 11 2020

...FROST ADVISORY HAS EXPIRED...

Temperatures will continue to rise this morning thus no longer
allowing frost to be a hazard to sensitive outdoor vegetation.
Therefore, the frost advisory has been allowed to expire.

$$

Nearby

Frost Advisories in Minnesota, 2020Frost Advisories in Wisconsin, 2020Every frost advisory in 2020

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.