Alert archive / Michigan / Frost Advisories in 2021

Frost Advisory 10, NWS Grand Rapids, MI

October 23, 202111 counties in Michigan

NWS Grand Rapids, MI issued this frost advisory at Oct 23, 2021, 1:17 PM EDT for 11 counties in Michigan. It took effect at Oct 24, 2021, 1:00 AM EDT. It was in force for 8 hr.

The area

The counties it named.

The facts

Issued
Oct 23, 2021, 1:17 PM EDT (17:17 UTC)
In effect from
Oct 24, 2021, 1:00 AM EDT
Expired
Oct 24, 2021, 9:00 AM EDT
In force
8 hr
Issued by
NWS Grand Rapids, MI

Counties Barry County, MI, Calhoun County, MI, Clinton County, MI, Eaton County, MI, Gratiot County, MI, Ingham County, MI, Ionia County, MI, Jackson County, MI, Kalamazoo County, MI, Kent County, MI, Montcalm County, MI

The radar

The Grand Rapids radar (KGRR), 52 km from the middle of the area, began a volume at 17:21 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, 5.3 hours before the alert went out and 124 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 2021-10-23Temperature 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, Detroit, MI at 12:00Z on 2021-10-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 69 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
679 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
69 m²/s²
0-3 km storm-relative helicity
144 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

791 
WWUS73 KGRR 231717
NPWGRR

URGENT - WEATHER MESSAGE
National Weather Service Grand Rapids MI
117 PM EDT Sat Oct 23 2021

MIZ051-052-057>059-065>067-072>074-240130-
/O.NEW.KGRR.FR.Y.0010.211024T0500Z-211024T1300Z/
Montcalm-Gratiot-Kent-Ionia-Clinton-Barry-Eaton-Ingham-Kalamazoo-
Calhoun-Jackson-
Including the cities of Greenville, Alma, Grand Rapids, Ionia, 
St. Johns, Hastings, Charlotte, Lansing, Kalamazoo, Battle Creek,
and Jackson
117 PM EDT Sat Oct 23 2021

...FROST ADVISORY IN EFFECT FROM 1 AM TO 9 AM EDT SUNDAY...

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

* WHERE...Portions of central, south central and southwest 
  Michigan.

* WHEN...From 1 AM to 9 AM EDT Sunday.

* IMPACTS...Temperatures near freezing could harm plants and 
  other sensitive outdoor vegetation if left uncovered.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

&&

$$

For more information from the National Weather Service visit
https://weather.gov/grr
4 follow-up statements
169 
WWUS73 KGRR 231937
NPWGRR

URGENT - WEATHER MESSAGE
National Weather Service Grand Rapids MI
337 PM EDT Sat Oct 23 2021

MIZ051-052-057>059-065>067-072>074-240345-
/O.CON.KGRR.FR.Y.0010.211024T0500Z-211024T1300Z/
Montcalm-Gratiot-Kent-Ionia-Clinton-Barry-Eaton-Ingham-Kalamazoo-
Calhoun-Jackson-
Including the cities of Greenville, Alma, Grand Rapids, Ionia, 
St. Johns, Hastings, Charlotte, Lansing, Kalamazoo, Battle Creek,
and Jackson
337 PM EDT Sat Oct 23 2021

...FROST ADVISORY REMAINS IN EFFECT FROM 1 AM TO 9 AM EDT
SUNDAY...

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

* WHERE...Portions of central, south central and southwest 
  Michigan.

* WHEN...From 1 AM to 9 AM EDT Sunday.

* IMPACTS...Temperatures near freezing could harm plants and 
  other sensitive outdoor vegetation if left uncovered.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

&&

$$

For more information from the National Weather Service visit
https://weather.gov/grr
654 
WWUS73 KGRR 240040
NPWGRR

URGENT - WEATHER MESSAGE
National Weather Service Grand Rapids MI
840 PM EDT Sat Oct 23 2021

MIZ051-052-057>059-065>067-072>074-240845-
/O.CON.KGRR.FR.Y.0010.211024T0500Z-211024T1300Z/
Montcalm-Gratiot-Kent-Ionia-Clinton-Barry-Eaton-Ingham-Kalamazoo-
Calhoun-Jackson-
Including the cities of Greenville, Alma, Grand Rapids, Ionia, 
St. Johns, Hastings, Charlotte, Lansing, Kalamazoo, Battle Creek,
and Jackson
840 PM EDT Sat Oct 23 2021

...FROST ADVISORY REMAINS IN EFFECT FROM 1 AM TO 9 AM EDT
SUNDAY...

* WHAT...Temperatures as low as 32 will result in frost 
  formation.

* WHERE...Portions of central, south central and southwest 
  Michigan.

* WHEN...From 1 AM to 9 AM EDT Sunday.

* IMPACTS...Temperatures near freezing could harm plants and 
  other sensitive outdoor vegetation if left uncovered.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

&&

$$

For more information from the National Weather Service visit
https://weather.gov/grr
176 
WWUS73 KGRR 240728
NPWGRR

URGENT - WEATHER MESSAGE
National Weather Service Grand Rapids MI
328 AM EDT Sun Oct 24 2021

MIZ051-052-057>059-065>067-072>074-241300-
/O.CON.KGRR.FR.Y.0010.000000T0000Z-211024T1300Z/
Montcalm-Gratiot-Kent-Ionia-Clinton-Barry-Eaton-Ingham-Kalamazoo-
Calhoun-Jackson-
Including the cities of Greenville, Alma, Grand Rapids, Ionia, 
St. Johns, Hastings, Charlotte, Lansing, Kalamazoo, Battle Creek,
and Jackson
328 AM EDT Sun Oct 24 2021

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

* WHAT...Temperatures as low as 32 will result in frost 
  formation.

* WHERE...Portions of central, south central and southwest 
  Michigan.

* WHEN...From 1 AM to 9 AM EDT Sunday.

* IMPACTS...Temperatures near freezing could harm plants and 
  other sensitive outdoor vegetation if left uncovered.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

&&

$$

For more information from the National Weather Service visit
https://weather.gov/grr
786 
WWUS73 KGRR 241302
NPWGRR

URGENT - WEATHER MESSAGE
National Weather Service Grand Rapids MI
902 AM EDT Sun Oct 24 2021

MIZ051-052-057>059-065>067-072>074-241415-
/O.EXP.KGRR.FR.Y.0010.000000T0000Z-211024T1300Z/
Montcalm-Gratiot-Kent-Ionia-Clinton-Barry-Eaton-Ingham-Kalamazoo-
Calhoun-Jackson-
Including the cities of Greenville, Alma, Grand Rapids, Ionia, 
St. Johns, Hastings, Charlotte, Lansing, Kalamazoo, Battle Creek,
and Jackson
902 AM EDT Sun Oct 24 2021

...FROST ADVISORY HAS EXPIRED...

Temperatures around freezing will quickly warm up over the next
hour as the fog burns off and morning sunshine takes over. Clouds
and rain tonight will keep temperatures much warmer, and no
additional frost is expected.

$$

For more information from the National Weather Service visit
https://weather.gov/grr

The office that day

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

IssuedProductOfficeCountiesLasted
Oct 23, 1:14 PM EDTGale WarningGRR55 hr

Nearby

Frost Advisories in Michigan, 2021Every frost 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.