Alert archive / Missouri / Freeze Warnings in 2021

Freeze Warning 2, NWS St. Louis, MO

March 31, 202121 counties in Missouri; 11 counties in Illinois

NWS St. Louis, MO issued this freeze warning at Mar 31, 2021, 2:44 PM CDT for 21 counties in Missouri; 11 counties in Illinois. It took effect at Apr 2, 2021, 1:00 AM CDT. It was in force for 8 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
Mar 31, 2021, 2:44 PM CDT (19:44 UTC)
In effect from
Apr 2, 2021, 1:00 AM CDT
Expired
Apr 2, 2021, 9:00 AM CDT
In force
8 hr
Issued by
NWS St. Louis, MO
All 32 counties

Bond County, IL, Calhoun County, IL, Clinton County, IL, Fayette County, IL, Jersey County, IL, Madison County, IL, Marion County, IL, Monroe County, IL, Randolph County, IL, Saint Clair County, IL, Washington County, IL, Boone County, MO, Callaway County, MO, City of Saint Louis, MO, Cole County, MO, Crawford County, MO, Franklin County, MO, Gasconade County, MO, Iron County, MO, Jefferson County, MO, Lincoln County, MO, Madison County, MO, Moniteau County, MO, Montgomery County, MO, Osage County, MO, Reynolds County, MO, Saint Charles County, MO, Saint Francois County, MO, Saint Louis County, MO, Sainte Genevieve County, MO, Warren County, MO, Washington County, MO

The radar

The St Louis radar (KLSX), 27 km from the middle of the area, began a volume at 19:45 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

Lincoln, IL (KILX), launched 12:00Z, 7.7 hours before the alert went out and 258 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, Lincoln, IL at 12:00Z on 2021-03-31Temperature 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, Lincoln, IL at 12:00Z on 2021-03-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -266 square meters per square second.1939587897117136Sfc1 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
1759 m above ground
0-6 km bulk shear
104 kt
0-1 km storm-relative helicity
-266 m²/s²
0-3 km storm-relative helicity
-176 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

777 
WWUS73 KLSX 311944
NPWLSX

URGENT - WEATHER MESSAGE
National Weather Service Saint Louis MO
244 PM CDT Wed Mar 31 2021

ILZ064-065-069-070-074-079-098>102-MOZ041-047>052-059>065-072>075-
084-085-099-011000-
/O.NEW.KLSX.FZ.W.0002.210402T0600Z-210402T1400Z/
/O.CON.KLSX.FZ.W.0001.210401T0600Z-210401T1400Z/
Bond IL-Boone MO-Calhoun IL-Callaway MO-Clinton IL-Cole MO-
Crawford MO-Fayette IL-Franklin MO-Gasconade MO-Iron MO-
Jefferson MO-Jersey IL-Lincoln MO-Madison IL-Madison MO-Marion IL-
Moniteau MO-Monroe IL-Montgomery MO-Osage MO-Randolph IL-
Reynolds MO-Saint Charles MO-Saint Clair-Saint Francois MO-
Saint Louis City MO-Saint Louis MO-Sainte Genevieve MO-Warren MO-
Washington IL-Washington MO-
Including the cities of Alton, Belleville, Cahokia, Centralia, 
Chester, Columbia, Edwardsville, Farmington, Fulton, 
Jefferson City, Saint Charles, Saint Louis, Salem, Sparta, 
Sullivan, Union, Vandalia, and Washington
244 PM CDT Wed Mar 31 2021

...FREEZE WARNING REMAINS IN EFFECT FROM 1 AM TO 9 AM CDT
THURSDAY...
...FREEZE WARNING IN EFFECT FROM 1 AM TO 9 AM CDT FRIDAY...

* WHAT...For the first Freeze Warning, sub-freezing temperatures
  in the low to mid 20s expected. For the second Freeze Warning,
  sub- freezing temperatures in the 20s expected.

* WHERE...Portions of central, east central and southeast 
  Missouri and south central and southwest Illinois.

* WHEN...For the first Freeze Warning, from 1 AM to 9 AM CDT 
  Thursday. For the second Freeze Warning, from 1 AM to 9 AM CDT 
  Friday.

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


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.

&&

$$

Byrd
5 follow-up statements
766 
WWUS73 KLSX 010849
NPWLSX

URGENT - WEATHER MESSAGE
National Weather Service Saint Louis MO
349 AM CDT Thu Apr 1 2021

ILZ064-065-069-070-074-079-098>102-MOZ041-047>052-059>065-072>075-
084-085-099-012200-
/O.CON.KLSX.FZ.W.0001.000000T0000Z-210401T1400Z/
/O.CON.KLSX.FZ.W.0002.210402T0600Z-210402T1400Z/
Bond IL-Boone MO-Calhoun IL-Callaway MO-Clinton IL-Cole MO-
Crawford MO-Fayette IL-Franklin MO-Gasconade MO-Iron MO-
Jefferson MO-Jersey IL-Lincoln MO-Madison IL-Madison MO-Marion IL-
Moniteau MO-Monroe IL-Montgomery MO-Osage MO-Randolph IL-
Reynolds MO-Saint Charles MO-Saint Clair-Saint Francois MO-
Saint Louis City MO-Saint Louis MO-Sainte Genevieve MO-Warren MO-
Washington IL-Washington MO-
Including the cities of Alton, Belleville, Cahokia, Centralia, 
Chester, Columbia, Edwardsville, Farmington, Fulton, 
Jefferson City, Saint Charles, Saint Louis, Salem, Sparta, 
Sullivan, Union, Vandalia, and Washington
349 AM CDT Thu Apr 1 2021

...FREEZE WARNING REMAINS IN EFFECT UNTIL 9 AM CDT THIS MORNING...
...FREEZE WARNING REMAINS IN EFFECT FROM 1 AM LATE TONIGHT TO 9 
AM CDT FRIDAY MORNING...

* WHAT...Sub-freezing temperatures in the 20s expected.

* WHERE...Portions of central, east central and southeast Missouri
  and southwest Illinois.

* WHEN...For the first Freeze Warning, until 9 AM CDT this morning.
  For the second Freeze Warning, from 1 AM to 9 AM CDT Friday.

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

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.

&&

$$

GKS
348 
WWUS73 KLSX 011403
NPWLSX

URGENT - WEATHER MESSAGE
National Weather Service Saint Louis MO
Issued by National Weather Service Lincoln IL
903 AM CDT Thu Apr 1 2021

ILZ064-065-069-070-074-079-098>102-MOZ041-047>052-059>065-072>075-
084-085-099-012300-
/O.EXP.KLSX.FZ.W.0001.000000T0000Z-210401T1400Z/
/O.CON.KLSX.FZ.W.0002.210402T0600Z-210402T1400Z/
Bond-Boone-Calhoun-Callaway-Clinton-Cole-Crawford-Fayette-
Franklin-Gasconade-Iron-Jefferson-Jersey-Lincoln-Madison-Marion-
Moniteau-Monroe-Montgomery-Osage-Randolph-Reynolds-St. Charles-
St. Clair-St. Francois-St. Louis-St. Louis City-Ste. Genevieve-
Warren-Washington-
Including the cities of Alton, Arnold, Belleville, Breese, 
California, Chester, Chesterfield, Columbia, East St. Louis, 
Edwardsville, Ellington, Farmington, Fredericktown, Fulton, 
Greenville, Hardin, Hermann, Ironton, Jefferson City, 
Jerseyville, Linn, Montgomery City, Nashville, Pacific, Potosi, 
Salem, St. Charles, St. Louis, St. Peters, Ste. Genevieve, 
Steelville, Troy, Vandalia, and Warrenton
903 AM CDT Thu Apr 1 2021

...FREEZE WARNING REMAINS IN EFFECT FROM 1 AM TO 9 AM CDT
FRIDAY...
...FREEZE WARNING FOR THIS MORNING HAS EXPIRED...

* WHAT...Sub-freezing temperatures in the 20s expected.

* WHERE...Portions of central, east central and southeast 
  Missouri and southwest Illinois.

* WHEN...From 1 AM to 9 AM CDT Friday.

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

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.

&&

$$

Geelhart
902 
WWUS73 KLSX 012002
NPWLSX

URGENT - WEATHER MESSAGE
National Weather Service Saint Louis MO
Issued by National Weather Service Lincoln IL
302 PM CDT Thu Apr 1 2021

ILZ064-065-069-070-074-079-098>102-MOZ041-047>052-059>065-072>075-
084-085-099-020900-
/O.CON.KLSX.FZ.W.0002.210402T0600Z-210402T1400Z/
Bond-Boone-Calhoun-Callaway-Clinton-Cole-Crawford-Fayette-
Franklin-Gasconade-Iron-Jefferson-Jersey-Lincoln-Madison-Marion-
Moniteau-Monroe-Montgomery-Osage-Randolph-Reynolds-St. Charles-
St. Clair-St. Francois-St. Louis-St. Louis City-Ste. Genevieve-
Warren-Washington-
Including the cities of Alton, Arnold, Belleville, Breese, 
California, Chester, Chesterfield, Columbia, East St. Louis, 
Edwardsville, Ellington, Farmington, Fredericktown, Fulton, 
Greenville, Hardin, Hermann, Ironton, Jefferson City, 
Jerseyville, Linn, Montgomery City, Nashville, Pacific, Potosi, 
Salem, St. Charles, St. Louis, St. Peters, Ste. Genevieve, 
Steelville, Troy, Vandalia, and Warrenton
302 PM CDT Thu Apr 1 2021

...FREEZE WARNING REMAINS IN EFFECT FROM 1 AM TO 9 AM CDT
FRIDAY...

* WHAT...Sub-freezing temperatures, ranging from the lower 20s
  over south central Illinois, to the mid 20s elsewhere. 

* WHERE...Portions of central, east central and southeast
  Missouri, and south central and southwest Illinois.

* WHEN...From 1 AM to 9 AM CDT Friday.

* IMPACTS...Frost and freeze conditions may kill early blooming
  plants and other sensitive vegetation if not covered. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Freeze Warning means sub-freezing temperatures are imminent or
highly likely. Cover any sensitive vegetation.

&&

$$

Geelhart
215 
WWUS73 KLSX 020847
NPWLSX

URGENT - WEATHER MESSAGE
National Weather Service Saint Louis MO
347 AM CDT Fri Apr 2 2021

ILZ064-065-069-070-074-079-098>102-MOZ041-047>052-059>065-072>075-
084-085-099-021400-
/O.CON.KLSX.FZ.W.0002.000000T0000Z-210402T1400Z/
Bond IL-Boone MO-Calhoun IL-Callaway MO-Clinton IL-Cole MO-
Crawford MO-Fayette IL-Franklin MO-Gasconade MO-Iron MO-
Jefferson MO-Jersey IL-Lincoln MO-Madison IL-Madison MO-Marion IL-
Moniteau MO-Monroe IL-Montgomery MO-Osage MO-Randolph IL-
Reynolds MO-Saint Charles MO-Saint Clair-Saint Francois MO-
Saint Louis City MO-Saint Louis MO-Sainte Genevieve MO-Warren MO-
Washington IL-Washington MO-
Including the cities of Alton, Belleville, Cahokia, Centralia, 
Chester, Columbia, Edwardsville, Farmington, Fulton, 
Jefferson City, Saint Charles, Saint Louis, Salem, Sparta, 
Sullivan, Union, Vandalia, and Washington
347 AM CDT Fri Apr 2 2021

...FREEZE WARNING REMAINS IN EFFECT UNTIL 9 AM CDT THIS MORNING...

* WHAT...Sub-freezing temperatures in the 20s.

* WHERE...Portions of central, east central and southeast
  Missouri, and southwest Illinois.

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

* IMPACTS...Frost and freeze conditions may kill early blooming 
  plants and other sensitive vegetation if not covered.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Freeze Warning means sub-freezing temperatures are imminent or
highly likely. Cover any sensitive vegetation.

&&

$$

GKS
608 
WWUS73 KLSX 021359
NPWLSX

URGENT - WEATHER MESSAGE
National Weather Service Saint Louis MO
859 AM CDT Fri Apr 2 2021

ILZ064-065-069-070-074-079-098>102-MOZ041-047>052-059>065-072>075-
084-085-099-021500-
/O.EXP.KLSX.FZ.W.0002.000000T0000Z-210402T1400Z/
Bond IL-Boone MO-Calhoun IL-Callaway MO-Clinton IL-Cole MO-
Crawford MO-Fayette IL-Franklin MO-Gasconade MO-Iron MO-
Jefferson MO-Jersey IL-Lincoln MO-Madison IL-Madison MO-Marion IL-
Moniteau MO-Monroe IL-Montgomery MO-Osage MO-Randolph IL-
Reynolds MO-Saint Charles MO-Saint Clair-Saint Francois MO-
Saint Louis City MO-Saint Louis MO-Sainte Genevieve MO-Warren MO-
Washington IL-Washington MO-
Including the cities of Alton, Belleville, Cahokia, Centralia, 
Chester, Columbia, Edwardsville, Farmington, Fulton, 
Jefferson City, Saint Charles, Saint Louis, Salem, Sparta, 
Sullivan, Union, Vandalia, and Washington
859 AM CDT Fri Apr 2 2021

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

Temperatures have risen above freezing in most areas, allowing 
the freeze warning to expire.

$$

BRC

The office that day

Everything else NWS St. Louis, MO issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 31, 4:31 AM CDTRed Flag WarningLSXAudrain, Boone, Callaway, Cole, Crawford, Franklin and 16 more14 hr

Nearby

Freeze Warnings in Missouri, 2021Freeze 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.