Alert archive / Illinois / Freeze Warnings in 2021

Freeze Warning 6, NWS Lincoln, IL

October 31, 2021Knox County, Marshall County, Stark County, Illinois

NWS Lincoln, IL issued this freeze warning at Oct 31, 2021, 8:14 PM CDT for Knox County, Marshall County, Stark County, Illinois. It took effect at Nov 1, 2021, 12:00 AM CDT. It was in force for 9 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Oct 31, 2021, 8:14 PM CDT (01:14 UTC)
In effect from
Nov 1, 2021, 12:00 AM CDT
Expired
Nov 1, 2021, 9:00 AM CDT
In force
9 hr
Issued by
NWS Lincoln, IL

Counties Knox County, IL, Marshall County, IL, Stark County, IL

The radar

The Quad Cities radar (KDVN), 94 km from the middle of the area, began a volume at 01:16 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

Davenport, (KDVN), launched 00:00Z, 1.2 hours before the alert went out and 90 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, Davenport, at 00:00Z on 2021-11-01Temperature 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, Davenport, at 00:00Z on 2021-11-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -47 square meters per square second.1939587897117Sfc1 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
1825 m above ground
0-6 km bulk shear
66 kt
0-1 km storm-relative helicity
-47 m²/s²
0-3 km storm-relative helicity
-20 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

594 
WWUS73 KILX 010114
NPWILX

URGENT - WEATHER MESSAGE
National Weather Service Lincoln IL
814 PM CDT Sun Oct 31 2021

ILZ027-028-030-011400-
/O.NEW.KILX.FZ.W.0006.211101T0500Z-211101T1400Z/
Knox-Stark-Marshall-
Including the cities of Galesburg, Toulon, and Lacon
814 PM CDT Sun Oct 31 2021

...FREEZE WARNING IN EFFECT FROM MIDNIGHT TONIGHT TO 9 AM CDT
MONDAY...

* WHAT...Sub-freezing temperatures as low as 30 expected.

* WHERE...Knox, Stark and Marshall Counties.

* WHEN...From midnight tonight to 9 AM CDT Monday.

* IMPACTS...Frost and freeze conditions will kill crops, other 
  sensitive vegetation and possibly damage unprotected outdoor 
  plumbing.

* ADDITIONAL DETAILS...Sub-freezing temperatures with lows as low
  as the upper 20s are possible several nights this week.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold. To prevent
freezing and possible bursting of outdoor water pipes they should
be wrapped, drained, or allowed to drip slowly. Those that have
in-ground sprinkler systems should drain them and cover above-
ground pipes to protect them from freezing.

&&

$$

Shimon
1 follow-up statement
591 
WWUS73 KILX 011355
NPWILX

URGENT - WEATHER MESSAGE
National Weather Service Lincoln IL
855 AM CDT Mon Nov 1 2021

ILZ027-028-030-011500-
/O.EXP.KILX.FZ.W.0006.000000T0000Z-211101T1400Z/
Knox-Stark-Marshall-
Including the cities of Galesburg, Toulon, and Lacon
855 AM CDT Mon Nov 1 2021

...FREEZE WARNING WILL EXPIRE AT 9 AM CDT THIS MORNING...

Temperatures have warmed into the mid-30s, therefore the freeze
warning has been allowed to expire. 

$$

Erwin

The office that day

Everything else NWS Lincoln, IL issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Nov 1, 2:41 PM CDTFreeze WarningILXCass, Champaign, DeWitt, Fulton, Knox, Logan and 15 more18 hr

Nearby

Freeze Warnings in Illinois, 2021Every freeze warning 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.