Alert archive / Iowa / Frost Advisories in 2021
Frost Advisory 4, NWS Des Moines, IA
NWS Des Moines, IA issued this frost advisory at May 11, 2021, 2:32 PM CDT for 11 counties in Iowa. It took effect at May 12, 2021, 2:00 AM CDT. It was in force for 5 hr.
The area
The counties it named.
The facts
- Issued
- May 11, 2021, 2:32 PM CDT (19:32 UTC)
- In effect from
- May 12, 2021, 2:00 AM CDT
- Expired
- May 12, 2021, 7:00 AM CDT
- In force
- 5 hr
- Issued by
- NWS Des Moines, IA
Counties Black Hawk County, IA, Bremer County, IA, Butler County, IA, Cerro Gordo County, IA, Franklin County, IA, Grundy County, IA, Hardin County, IA, Marshall County, IA, Poweshiek County, IA, Tama County, IA, Worth County, IA
The radar
The Des Moines radar (KDMX), 114 km from the middle of the area, began a volume at 19:34 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, 7.5 hours before the alert went out and 218 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.
- Mixed-layer CAPE
- 15 J/kg
- Mixed-layer CIN
- -35 J/kg
- Mixed-layer LCL
- 1155 m above ground
- 0-6 km bulk shear
- 53 kt
- 0-1 km storm-relative helicity
- -29 m²/s²
- 0-3 km storm-relative helicity
- 47 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
826 WWUS73 KDMX 111932 NPWDMX URGENT - WEATHER MESSAGE National Weather Service Des Moines IA 232 PM CDT Tue May 11 2021 IAZ007-017-026>028-037>039-049-050-062-120345- /O.NEW.KDMX.FR.Y.0004.210512T0700Z-210512T1200Z/ Worth-Cerro Gordo-Franklin-Butler-Bremer-Hardin-Grundy-Black Hawk- Marshall-Tama-Poweshiek- Including the cities of Northwood, Manly, Mason City, Clear Lake, Hampton, Parkersburg, Clarksville, Shell Rock, Greene, Aplington, Allison, Dumont, Waverly, Iowa Falls, Eldora, Ackley, Grundy Center, Reinbeck, Conrad, Dike, Wellsburg, Waterloo, Cedar Falls, Marshalltown, Tama, Toledo, Traer, Dysart, Gladbrook, and Grinnell 232 PM CDT Tue May 11 2021 ...FROST ADVISORY IN EFFECT FROM 2 AM TO 7 AM CDT WEDNESDAY... * WHAT...Temperatures as low as 34 will result in frost formation. * WHERE...Much of the east to northeast half of Iowa. * WHEN...From 2 AM to 7 AM CDT Wednesday. * IMPACTS...Frost could kill sensitive outdoor vegetation if left uncovered. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. && $$ For more information from the National Weather Service visit https://weather.gov/desmoines
2 follow-up statements
657 WWUS73 KDMX 120152 NPWDMX URGENT - WEATHER MESSAGE National Weather Service Des Moines IA 852 PM CDT Tue May 11 2021 IAZ007-017-026>028-037>039-049-050-062-121000- /O.CON.KDMX.FR.Y.0004.210512T0700Z-210512T1200Z/ Worth-Cerro Gordo-Franklin-Butler-Bremer-Hardin-Grundy-Black Hawk- Marshall-Tama-Poweshiek- Including the cities of Northwood, Manly, Mason City, Clear Lake, Hampton, Parkersburg, Clarksville, Shell Rock, Greene, Aplington, Allison, Dumont, Waverly, Iowa Falls, Eldora, Ackley, Grundy Center, Reinbeck, Conrad, Dike, Wellsburg, Waterloo, Cedar Falls, Marshalltown, Tama, Toledo, Traer, Dysart, Gladbrook, and Grinnell 852 PM CDT Tue May 11 2021 ...FROST ADVISORY REMAINS IN EFFECT FROM 2 AM TO 7 AM CDT WEDNESDAY... * WHAT...Temperatures as low as 34 will result in frost formation. * WHERE...Much of the east to northeast half of Iowa. * WHEN...From 2 AM to 7 AM CDT Wednesday. * IMPACTS...Frost could kill sensitive outdoor vegetation if left uncovered. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. && $$ Krull For more information from the National Weather Service visit https://weather.gov/desmoines
806 WWUS73 KDMX 121159 NPWDMX URGENT - WEATHER MESSAGE National Weather Service Des Moines IA 659 AM CDT Wed May 12 2021 IAZ007-017-026>028-037>039-049-050-062-121300- /O.EXP.KDMX.FR.Y.0004.000000T0000Z-210512T1200Z/ Worth-Cerro Gordo-Franklin-Butler-Bremer-Hardin-Grundy-Black Hawk- Marshall-Tama-Poweshiek- Including the cities of Northwood, Manly, Mason City, Clear Lake, Hampton, Parkersburg, Clarksville, Shell Rock, Greene, Aplington, Allison, Dumont, Waverly, Iowa Falls, Eldora, Ackley, Grundy Center, Reinbeck, Conrad, Dike, Wellsburg, Waterloo, Cedar Falls, Marshalltown, Tama, Toledo, Traer, Dysart, Gladbrook, and Grinnell 659 AM CDT Wed May 12 2021 ...FROST ADVISORY WILL EXPIRE AT 7 AM CDT THIS MORNING... Temperatures will warm over the next hour ending the threat for frost. $$ For more information from the National Weather Service visit https://weather.gov/desmoines
Nearby
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.