Alert archive / Kansas / Frost Advisories in 2021

Frost Advisory 6, NWS Topeka, KS

October 21, 20216 counties in Kansas

NWS Topeka, KS issued this frost advisory at Oct 21, 2021, 3:11 AM CDT for 6 counties in Kansas. It took effect at Oct 22, 2021, 3:00 AM CDT. It was in force for 6 hr.

The area

The counties it named.

The facts

Issued
Oct 21, 2021, 3:11 AM CDT (08:11 UTC)
In effect from
Oct 22, 2021, 3:00 AM CDT
Expired
Oct 22, 2021, 9:00 AM CDT
In force
6 hr
Issued by
NWS Topeka, KS

Counties Brown County, KS, Cloud County, KS, Marshall County, KS, Nemaha County, KS, Republic County, KS, Washington County, KS

The radar

The Topeka radar (KTWX), 95 km from the middle of the area, began a volume at 08:15 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

Topeka, KS (KTOP), launched 00:00Z, 8.2 hours before the alert went out and 126 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, Topeka, KS at 00:00Z on 2021-10-21Temperature 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, Topeka, KS at 00:00Z on 2021-10-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -69 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
1694 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
-69 m²/s²
0-3 km storm-relative helicity
33 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

015 
WWUS73 KTOP 210811
NPWTOP

URGENT - WEATHER MESSAGE
National Weather Service Topeka KS
311 AM CDT Thu Oct 21 2021

KSZ008>012-020-220000-
/O.NEW.KTOP.FR.Y.0006.211022T0800Z-211022T1400Z/
Republic-Washington-Marshall-Nemaha-Brown-Cloud-
Including the cities of Belleville, Washington, Hanover, Clifton,
Linn, Greenleaf, Marysville, Blue Rapids, Frankfort, Sabetha, 
Seneca, Hiawatha, Horton, and Concordia
311 AM CDT Thu Oct 21 2021

...FROST ADVISORY IN EFFECT FROM 3 AM TO 9 AM CDT FRIDAY...

* WHAT...Temperatures as low as 34 degrees will result in frost 
  formation.

* WHERE...Republic, Washington, Marshall, Nemaha, Brown and 
  Cloud Counties.

* WHEN...From 3 AM 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
107 
WWUS73 KTOP 211941
NPWTOP

URGENT - WEATHER MESSAGE
National Weather Service Topeka KS
241 PM CDT Thu Oct 21 2021

KSZ008>012-020-220930-
/O.CON.KTOP.FR.Y.0006.211022T0800Z-211022T1400Z/
Republic-Washington-Marshall-Nemaha-Brown-Cloud-
Including the cities of Belleville, Washington, Hanover, Clifton,
Linn, Greenleaf, Marysville, Blue Rapids, Frankfort, Sabetha, 
Seneca, Hiawatha, Horton, and Concordia
241 PM CDT Thu Oct 21 2021

...FROST ADVISORY REMAINS IN EFFECT FROM 3 AM TO 9 AM CDT
FRIDAY...

* WHAT...Temperatures falling into the middle 30s will combine
  with light winds and clear skies to allow frost to form. 

* WHERE...Republic, Washington, Marshall, Nemaha, Brown and 
  Cloud Counties.

* WHEN...From 3 AM 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.

&&

$$
281 
WWUS73 KTOP 220900
NPWTOP

URGENT - WEATHER MESSAGE
National Weather Service Topeka KS
400 AM CDT Fri Oct 22 2021

KSZ008>012-020-221400-
/O.CON.KTOP.FR.Y.0006.000000T0000Z-211022T1400Z/
Republic-Washington-Marshall-Nemaha-Brown-Cloud-
Including the cities of Belleville, Washington, Hanover, Clifton,
Linn, Greenleaf, Marysville, Blue Rapids, Frankfort, Sabetha, 
Seneca, Hiawatha, Horton, and Concordia
400 AM CDT Fri Oct 22 2021

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

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

* WHERE...Nemaha, Marshall, Brown, Republic, Washington and 
  Cloud Counties.

* WHEN...Until 9 AM CDT this morning.

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

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

&&

$$
304 
WWUS73 KTOP 221345
NPWTOP

URGENT - WEATHER MESSAGE
National Weather Service Topeka KS
845 AM CDT Fri Oct 22 2021

KSZ008>012-020-221445-
/O.EXP.KTOP.FR.Y.0006.000000T0000Z-211022T1400Z/
Republic-Washington-Marshall-Nemaha-Brown-Cloud-
Including the cities of Belleville, Washington, Hanover, Clifton,
Linn, Greenleaf, Marysville, Blue Rapids, Frankfort, Sabetha, 
Seneca, Hiawatha, Horton, and Concordia
845 AM CDT Fri Oct 22 2021

...FROST ADVISORY WILL EXPIRE AT 9 AM CDT THIS MORNING...

Full sunshine and warming temperatures will bring an end to this 
morning's frost. 

$$

Nearby

Frost Advisories in Kansas, 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.