Alert archive / Iowa / Frost Advisories in 2012

Frost Advisory 2, NWS Quad Cities, IA

April 20, 201216 counties in Iowa; 5 counties in Illinois

NWS Quad Cities, IA issued this frost advisory at Apr 20, 2012, 3:24 PM CDT for 16 counties in Iowa; 5 counties in Illinois. It took effect at Apr 21, 2012, 3:00 AM CDT. It was in force for 5 hr.

The area

The counties it named.

The facts

Issued
Apr 20, 2012, 3:24 PM CDT (20:24 UTC)
In effect from
Apr 21, 2012, 3:00 AM CDT
Expired
Apr 21, 2012, 8:00 AM CDT
In force
5 hr
Issued by
NWS Quad Cities, IA
All 21 counties

Benton County, IA, Buchanan County, IA, Cedar County, IA, Clinton County, IA, Delaware County, IA, Dubuque County, IA, Iowa County, IA, Jackson County, IA, Johnson County, IA, Jones County, IA, Keokuk County, IA, Linn County, IA, Louisa County, IA, Muscatine County, IA, Scott County, IA, Washington County, IA, Bureau County, IL, Henry County, IL, Mercer County, IL, Putnam County, IL, Rock Island County, IL

The radar

The Quad Cities radar (KDVN), 41 km from the middle of the area, began a volume at 20:29 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, 8.4 hours before the alert went out and 47 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 2012-04-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3 joules per kilogram.LCLEL10008507005003002001001 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 2012-04-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -43 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
3 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
455 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
-43 m²/s²
0-3 km storm-relative helicity
-6 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.

317 
WWUS73 KDVN 202024
NPWDVN

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
324 PM CDT FRI APR 20 2012

...FROST AND FREEZING TEMPERATURES ARE EXPECTED TONIGHT...

.CONDITIONS WILL BE FAVORABLE TONIGHT FOR TEMPERATURES AT OR BELOW
FREEZING OVER NORTHWEST ILLINOIS AND FOR AREAS OF FROST OVER PARTS
OF EAST CENTRAL IOWA AND WEST CENTRAL ILLINOIS. SKIES WILL CLEAR
BY EARLY THIS EVENING WITH WINDS BECOMING LIGHT AS HIGH PRESSURE
MOVES INTO THE REGION. THE CLEAR SKIES AND LIGHT WINDS WILL CREATE
FAVORABLE CONDITIONS FOR FREEZING OR NEAR FREEZING TEMPERATURES
AND AREAS OF FROST BY LATE TONIGHT.  

ILZ001-002-007-009-210630-
/O.NEW.KDVN.FZ.W.0005.120421T0800Z-120421T1300Z/
JO DAVIESS-STEPHENSON-CARROLL-WHITESIDE-
INCLUDING THE CITIES OF...GALENA...FREEPORT...MOUNT CARROLL...
STERLING...ROCK FALLS
324 PM CDT FRI APR 20 2012

...FREEZE WARNING IN EFFECT FROM 3 AM TO 8 AM CDT SATURDAY...

THE NATIONAL WEATHER SERVICE IN QUAD CITIES HAS ISSUED A FREEZE
WARNING...WHICH IS IN EFFECT FROM 3 AM TO 8 AM CDT SATURDAY. 

* TIMING...TEMPERATURES ARE EXPECTED TO DROP INTO THE LOWER 30S BY
  3 AM AND WILL REMAIN AT OR BELOW FREEZING FOR SEVERAL HOURS.

* IMPACTS...THE COLD TEMPERATURES WILL CAUSE DAMAGE TO SENSITIVE
  OUTDOOR PLANTS THE ARE NOT PROTECTED.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FREEZE WARNING MEANS SUB-FREEZING TEMPERATURES ARE IMMINENT OR
HIGHLY LIKELY.  THESE CONDITIONS WILL KILL CROPS AND OTHER
SENSITIVE VEGETATION. COVER SENSITIVE PLANTS OR BRING INDOORS FOR
PROTECTION.

&&

$$

IAZ040>042-051>054-063>068-076>078-ILZ015>018-024-210630-
/O.NEW.KDVN.FR.Y.0002.120421T0800Z-120421T1300Z/
BUCHANAN-DELAWARE-DUBUQUE-BENTON-LINN-JONES-JACKSON-IOWA-JOHNSON-
CEDAR-CLINTON-MUSCATINE-SCOTT-KEOKUK-WASHINGTON-LOUISA-
ROCK ISLAND-HENRY IL-BUREAU-PUTNAM-MERCER-
INCLUDING THE CITIES OF...INDEPENDENCE...MANCHESTER...DUBUQUE...
VINTON...CEDAR RAPIDS...ANAMOSA...MAQUOKETA...MARENGO...
IOWA CITY...TIPTON...CLINTON...MUSCATINE...BETTENDORF...
DAVENPORT...SIGOURNEY...WASHINGTON...WAPELLO...MOLINE...
ROCK ISLAND...KEWANEE...PRINCETON...HENNEPIN...ALEDO
324 PM CDT FRI APR 20 2012

...FROST ADVISORY IN EFFECT FROM 3 AM TO 8 AM CDT SATURDAY...

THE NATIONAL WEATHER SERVICE IN QUAD CITIES HAS ISSUED A FROST
ADVISORY...WHICH IS IN EFFECT FROM 3 AM TO 8 AM CDT SATURDAY. 

* TIMING...TEMPERATURES WILL FALL INTO THE MIDDLE 30S LATE
  TONIGHT. THE COLD TEMPERATURES...MOSTLY CLEAR SKIES AND LIGHT
  WINDS WILL CREATE FAVORABLE CONDITIONS FOR FROST FORMATION

* IMPACTS...THE FROST WILL CAUSE DAMAGE TO SENSITIVE OUTDOOR
  PLANTS THAT ARE NOT PROTECTED. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FROST ADVISORY MEANS THAT FROST IS LIKELY.  COVER OR MOVE
SENSITIVE PLANTS INDOORS.

&&

$$
3 follow-up statements
976 
WWUS73 KDVN 210213
NPWDVN

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
913 PM CDT FRI APR 20 2012

...FROST AND FREEZING TEMPERATURES ARE EXPECTED TONIGHT...

.CONDITIONS WILL BE FAVORABLE TONIGHT FOR TEMPERATURES AT OR
BELOW FREEZING OVER NORTHWEST ILLINOIS AND FOR AREAS OF FROST
OVER PARTS OF EAST CENTRAL IOWA AND WEST CENTRAL ILLINOIS. SKIES
WILL CONTINUE TO CLEAR THIS EVENING WITH WINDS BECOMING LIGHT AS
HIGH PRESSURE MOVES INTO THE REGION. THE CLEAR SKIES AND LIGHT
WINDS WILL CREATE FAVORABLE CONDITIONS FOR FREEZING OR NEAR
FREEZING TEMPERATURES AND AREAS OF FROST BY LATE TONIGHT.

ILZ001-002-007-009-211215-
/O.CON.KDVN.FZ.W.0005.120421T0800Z-120421T1300Z/
JO DAVIESS-STEPHENSON-CARROLL-WHITESIDE-
INCLUDING THE CITIES OF...GALENA...FREEPORT...MOUNT CARROLL...
STERLING...ROCK FALLS
913 PM CDT FRI APR 20 2012

...FREEZE WARNING REMAINS IN EFFECT FROM 3 AM TO 8 AM CDT
SATURDAY...

* TIMING...TEMPERATURES ARE EXPECTED TO DROP INTO THE LOWER 30S 
  BY 3 AM AND WILL REMAIN AT OR BELOW FREEZING FOR SEVERAL 
  HOURS. 

* IMPACTS...THE COLD TEMPERATURES WILL CAUSE DAMAGE TO SENSITIVE 
  OUTDOOR PLANTS THE ARE NOT PROTECTED. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FREEZE WARNING MEANS SUB-FREEZING TEMPERATURES ARE IMMINENT OR
HIGHLY LIKELY.  THESE CONDITIONS WILL KILL CROPS AND OTHER
SENSITIVE VEGETATION. COVER SENSITIVE PLANTS OR BRING INDOORS FOR
PROTECTION.

&&

$$

IAZ040>042-051>054-063>068-076>078-ILZ015>018-024-211215-
/O.CON.KDVN.FR.Y.0002.120421T0800Z-120421T1300Z/
BUCHANAN-DELAWARE-DUBUQUE-BENTON-LINN-JONES-JACKSON-IOWA-JOHNSON-
CEDAR-CLINTON-MUSCATINE-SCOTT-KEOKUK-WASHINGTON-LOUISA-
ROCK ISLAND-HENRY IL-BUREAU-PUTNAM-MERCER-
INCLUDING THE CITIES OF...INDEPENDENCE...MANCHESTER...DUBUQUE...
VINTON...CEDAR RAPIDS...ANAMOSA...MAQUOKETA...MARENGO...
IOWA CITY...TIPTON...CLINTON...MUSCATINE...BETTENDORF...
DAVENPORT...SIGOURNEY...WASHINGTON...WAPELLO...MOLINE...
ROCK ISLAND...KEWANEE...PRINCETON...HENNEPIN...ALEDO
913 PM CDT FRI APR 20 2012

...FROST ADVISORY REMAINS IN EFFECT FROM 3 AM TO 8 AM CDT
SATURDAY...

* TIMING...TEMPERATURES WILL FALL INTO THE MIDDLE 30S LATE 
  TONIGHT. THE COLD TEMPERATURES...MOSTLY CLEAR SKIES AND LIGHT 
  WINDS WILL CREATE FAVORABLE CONDITIONS FOR FROST FORMATION 

* IMPACTS...THE FROST WILL CAUSE DAMAGE TO SENSITIVE OUTDOOR 
  PLANTS THAT ARE NOT PROTECTED. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FROST ADVISORY MEANS THAT FROST IS LIKELY.  COVER OR MOVE
SENSITIVE PLANTS INDOORS.

&&

$$
989 
WWUS73 KDVN 210839
NPWDVN

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
339 AM CDT SAT APR 21 2012

...FROST AND FREEZING TEMPERATURES ARE EXPECTED TONIGHT...

.LIGHT WINDS AND INITIALLY CLEAR SKIES HAVE ALLOWED TEMPERATURES
TO DROP INTO THE 30S. FROST IS STILL POSSIBLE PRIOR TO SUNRISE
ALONG WITH TEMPERATURES RIGHT AROUND FREEZING IN SOME LOCATIONS.

ILZ001-002-007-009-211300-
/O.CON.KDVN.FZ.W.0005.000000T0000Z-120421T1300Z/
JO DAVIESS-STEPHENSON-CARROLL-WHITESIDE-
INCLUDING THE CITIES OF...GALENA...FREEPORT...MOUNT CARROLL...
STERLING...ROCK FALLS
339 AM CDT SAT APR 21 2012

...FREEZE WARNING REMAINS IN EFFECT UNTIL 8 AM CDT THIS MORNING...

* TIMING...TEMPERATURES NEAR FREEZING THROUGH SUNRISE.

* IMPACTS...THE COLD TEMPERATURES WILL CAUSE DAMAGE TO SENSITIVE 
  OUTDOOR PLANTS THE ARE NOT PROTECTED. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FREEZE WARNING MEANS SUB-FREEZING TEMPERATURES ARE IMMINENT OR
HIGHLY LIKELY.  THESE CONDITIONS WILL KILL CROPS AND OTHER
SENSITIVE VEGETATION. COVER SENSITIVE PLANTS OR BRING INDOORS FOR
PROTECTION.

&&

$$

IAZ040>042-051>054-063>068-076>078-ILZ015>018-024-211300-
/O.CON.KDVN.FR.Y.0002.000000T0000Z-120421T1300Z/
BUCHANAN-DELAWARE-DUBUQUE-BENTON-LINN-JONES-JACKSON-IOWA-JOHNSON-
CEDAR-CLINTON-MUSCATINE-SCOTT-KEOKUK-WASHINGTON-LOUISA-
ROCK ISLAND-HENRY IL-BUREAU-PUTNAM-MERCER-
INCLUDING THE CITIES OF...INDEPENDENCE...MANCHESTER...DUBUQUE...
VINTON...CEDAR RAPIDS...ANAMOSA...MAQUOKETA...MARENGO...
IOWA CITY...TIPTON...CLINTON...MUSCATINE...BETTENDORF...
DAVENPORT...SIGOURNEY...WASHINGTON...WAPELLO...MOLINE...
ROCK ISLAND...KEWANEE...PRINCETON...HENNEPIN...ALEDO
339 AM CDT SAT APR 21 2012

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

* TIMING...TEMPERATURES IN THE MID 30S WITH LIGHT WINDS WILL
  CREATE FAVORABLE CONDITIONS FOR FROST THROUGH SUNRISE.

* IMPACTS...THE FROST WILL CAUSE DAMAGE TO SENSITIVE OUTDOOR 
  PLANTS THAT ARE NOT PROTECTED. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FROST ADVISORY MEANS THAT FROST IS LIKELY.  COVER OR MOVE
SENSITIVE PLANTS INDOORS.

&&

$$
620 
WWUS73 KDVN 211302
NPWDVN

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
802 AM CDT SAT APR 21 2012


ILZ001-002-007-009-211415-
/O.EXP.KDVN.FZ.W.0005.000000T0000Z-120421T1300Z/
JO DAVIESS-STEPHENSON-CARROLL-WHITESIDE-
INCLUDING THE CITIES OF...GALENA...FREEPORT...MOUNT CARROLL...
STERLING...ROCK FALLS
802 AM CDT SAT APR 21 2012

...FREEZE WARNING HAS EXPIRED...

TEMPERATURES HAVE CLIMBED ABOVE FREEZING. THUS THE FREEZE WARNING
HAS EXPIRED.


$$

IAZ040>042-051>054-063>068-076>078-ILZ015>018-024-211415-
/O.EXP.KDVN.FR.Y.0002.000000T0000Z-120421T1300Z/
BUCHANAN-DELAWARE-DUBUQUE-BENTON-LINN-JONES-JACKSON-IOWA-JOHNSON-
CEDAR-CLINTON-MUSCATINE-SCOTT-KEOKUK-WASHINGTON-LOUISA-
ROCK ISLAND-HENRY IL-BUREAU-PUTNAM-MERCER-
INCLUDING THE CITIES OF...INDEPENDENCE...MANCHESTER...DUBUQUE...
VINTON...CEDAR RAPIDS...ANAMOSA...MAQUOKETA...MARENGO...
IOWA CITY...TIPTON...CLINTON...MUSCATINE...BETTENDORF...
DAVENPORT...SIGOURNEY...WASHINGTON...WAPELLO...MOLINE...
ROCK ISLAND...KEWANEE...PRINCETON...HENNEPIN...ALEDO
802 AM CDT SAT APR 21 2012

...FROST ADVISORY HAS EXPIRED...

TEMPERATURES HAVE CLIMBED INTO THE MID AND UPPER 30S. THUS THE
FROST ADVISORY HAS EXPIRED.


$$

The office that day

Everything else NWS Quad Cities, IA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 20, 3:24 PM CDTFreeze WarningDVNCarroll, Jo Daviess, Stephenson, Whiteside17 hr

Nearby

Frost Advisories in Iowa, 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.