Alert archive / Missouri / Frost Advisories in 2012

Frost Advisory 2, NWS St. Louis, MO

September 22, 2012Adams County, Brown County, Pike County, Illinois; 4 counties in Missouri

NWS St. Louis, MO issued this frost advisory at Sep 22, 2012, 3:50 PM CDT for Adams County, Brown County, Pike County, Illinois; 4 counties in Missouri. It took effect at Sep 23, 2012, 4:00 AM CDT. It was in force for 4 hr.

The area

The counties it named.

The facts

Issued
Sep 22, 2012, 3:50 PM CDT (20:50 UTC)
In effect from
Sep 23, 2012, 4:00 AM CDT
Expired
Sep 23, 2012, 8:00 AM CDT
In force
4 hr
Issued by
NWS St. Louis, MO

Counties Adams County, IL, Brown County, IL, Pike County, IL, Knox County, MO, Lewis County, MO, Marion County, MO, Shelby County, MO

The radar

The St Louis radar (KLSX), 152 km from the middle of the area, began a volume at 20:49 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 12:00Z, 8.8 hours before the alert went out and 207 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 12:00Z on 2012-09-22Temperature 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 12:00Z on 2012-09-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -95 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
1551 m above ground
0-6 km bulk shear
99 kt
0-1 km storm-relative helicity
-95 m²/s²
0-3 km storm-relative helicity
25 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

765 
WWUS73 KLSX 222050
NPWLSX

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE ST LOUIS MO
350 PM CDT SAT SEP 22 2012

ILZ095>097-MOZ018-019-026-027-230900-
/O.NEW.KLSX.FR.Y.0002.120923T0900Z-120923T1300Z/
ADAMS IL-BROWN IL-PIKE IL-KNOX MO-LEWIS MO-SHELBY MO-MARION MO-
INCLUDING THE CITIES OF...QUINCY...HANNIBAL
350 PM CDT SAT SEP 22 2012

...FROST ADVISORY IN EFFECT FROM 4 AM TO 8 AM CDT SUNDAY...

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A FROST
ADVISORY...WHICH IS IN EFFECT FROM 4 AM TO 8 AM CDT SUNDAY. 

* TIMING...LATE TONIGHT AND EARLY TOMORROW MORNING.

* TEMPERATURES...MID TO UPPER 30S.

* IMPACTS...FROST MAY DAMAGE SENSITIVE VEGETATION IF IT IS LEFT
  UNPROTECTED.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FROST ADVISORY IS ISSUED WHEN FROST IS EXPECTED TO DEVELOP
DURING THE GROWING SEASON. THOSE WITH AGRICULTURAL INTERESTS IN
THE ADVISORY AREA SHOULD PROTECT TENDER VEGETATION. ALSO...POTTED
PLANTS NORMALLY LEFT OUTDOORS SHOULD BE COVERED OR BROUGHT INSIDE
AWAY FROM THE COLD.

&&

$$

KANOFSKY
2 follow-up statements
165 
WWUS73 KLSX 230857
NPWLSX

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE ST LOUIS MO
357 AM CDT SUN SEP 23 2012

ILZ095>097-MOZ018-019-026-027-231300-
/O.CON.KLSX.FR.Y.0002.120923T0900Z-120923T1300Z/
ADAMS IL-BROWN IL-PIKE IL-KNOX MO-LEWIS MO-SHELBY MO-MARION MO-
INCLUDING THE CITIES OF...QUINCY...HANNIBAL
357 AM CDT SUN SEP 23 2012

...FROST ADVISORY REMAINS IN EFFECT UNTIL 8 AM CDT THIS MORNING...

* TIMING...THROUGH 8AM. 

* TEMPERATURES...MID TO UPPER 30S THROUGH DAYBREAK...WITH A RAPID
  WARMUP AFTER 8AM.   

* IMPACTS...FROST MAY DAMAGE SENSITIVE VEGETATION IF IT IS LEFT 
  UNPROTECTED. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FROST ADVISORY IS ISSUED WHEN FROST IS EXPECTED TO DEVELOP
DURING THE GROWING SEASON. THOSE WITH AGRICULTURAL INTERESTS IN
THE ADVISORY AREA SHOULD PROTECT TENDER VEGETATION. ALSO...POTTED
PLANTS NORMALLY LEFT OUTDOORS SHOULD BE COVERED OR BROUGHT INSIDE
AWAY FROM THE COLD.

&&

$$

TRUETT
621 
WWUS73 KLSX 231253
NPWLSX

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE ST LOUIS MO
753 AM CDT SUN SEP 23 2012


ILZ095>097-MOZ018-019-026-027-231400-
/O.EXP.KLSX.FR.Y.0002.000000T0000Z-120923T1300Z/
ADAMS IL-BROWN IL-PIKE IL-KNOX MO-LEWIS MO-SHELBY MO-MARION MO-
INCLUDING THE CITIES OF...QUINCY...HANNIBAL
753 AM CDT SUN SEP 23 2012

...FROST ADVISORY WILL EXPIRE AT 8 AM CDT THIS MORNING...

TEMPERATURES HAVE BEGUN TO RISE UNDER SUNNY SKIES...SO ANY FROST THAT
FORMED OVERNIGHT WILL BEGIN TO DISSIPATE. THE ADVISORY HAS BEEN
ALLOWED TO EXPIRE.

$$

BYRD

Nearby

Frost Advisories in Missouri, 2012Frost Advisories in Illinois, 2012Every frost advisory in 2012

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.