Alert archive / South Dakota / Frost Advisories in 2021

Frost Advisory 4, NWS Sioux Falls, SD

May 9, 202111 counties in South Dakota

NWS Sioux Falls, SD issued this frost advisory at May 9, 2021, 3:22 PM CDT for 11 counties in South Dakota. It took effect at May 10, 2021, 4:00 AM CDT. It was in force for 4 hr.

The area

The counties it named.

The facts

Issued
May 9, 2021, 3:22 PM CDT (20:22 UTC)
In effect from
May 10, 2021, 4:00 AM CDT
Expired
May 10, 2021, 8:00 AM CDT
In force
4 hr
Issued by
NWS Sioux Falls, SD

Counties Aurora County, SD, Beadle County, SD, Brookings County, SD, Brule County, SD, Davison County, SD, Douglas County, SD, Hanson County, SD, Jerauld County, SD, Kingsbury County, SD, Miner County, SD, Sanborn County, SD

The radar

The Sioux Falls radar (KFSD), 115 km from the middle of the area, began a volume at 20:25 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

Aberdeen, SD (KABR), launched 12:00Z, 8.4 hours before the alert went out and 109 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, Aberdeen, SD at 12:00Z on 2021-05-09Temperature 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, Aberdeen, SD at 12:00Z on 2021-05-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 87 square meters per square second.193958Sfc1 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
1677 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
87 m²/s²
0-3 km storm-relative helicity
110 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

382 
WWUS73 KFSD 092022
NPWFSD

URGENT - WEATHER MESSAGE
National Weather Service Sioux Falls SD
322 PM CDT Sun May 9 2021

SDZ038-039-052-053-100430-
/O.NEW.KFSD.FR.Y.0004.210510T0900Z-210510T1300Z/
Beadle-Kingsbury-Jerauld-Sanborn-
322 PM CDT Sun May 9 2021

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

* WHAT...Temperatures as low as 33 to 35 will result in frost 
  formation.

* WHERE...Beadle, Kingsbury, Jerauld and Sanborn Counties.

* WHEN...From 4 AM to 8 AM CDT Monday.

* 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/siouxfalls
3 follow-up statements
496 
WWUS73 KFSD 100141
NPWFSD

URGENT - WEATHER MESSAGE
National Weather Service Sioux Falls SD
841 PM CDT Sun May 9 2021

SDZ040-054-057>060-064-100945-
/O.EXA.KFSD.FR.Y.0004.210510T0900Z-210510T1300Z/
Brookings-Miner-Brule-Aurora-Davison-Hanson-Douglas-
841 PM CDT Sun May 9 2021

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

* WHAT...Temperatures as low as 33 will result in frost 
  formation.

* WHERE...Brookings, Miner, Brule, Aurora, Davison, Hanson and 
  Douglas Counties.

* WHEN...From 4 AM to 8 AM CDT Monday.

* IMPACTS...Frost could kill sensitive outdoor vegetation if 
  left uncovered.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

&&

$$

SDZ038-039-052-053-100945-
/O.CON.KFSD.FR.Y.0004.210510T0900Z-210510T1300Z/
Beadle-Kingsbury-Jerauld-Sanborn-
841 PM CDT Sun May 9 2021

...FROST ADVISORY REMAINS IN EFFECT FROM 4 AM TO 8 AM CDT
MONDAY...

* WHAT...Temperatures as low as 32 will result in frost 
  formation.

* WHERE...Jerauld, Sanborn, Beadle and Kingsbury Counties.

* WHEN...From 4 AM to 8 AM CDT Monday.

* 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/siouxfalls
919 
WWUS73 KFSD 100503
NPWFSD

URGENT - WEATHER MESSAGE
National Weather Service Sioux Falls SD
1203 AM CDT Mon May 10 2021

SDZ038>040-052>054-057>060-064-101300-
/O.CON.KFSD.FR.Y.0004.210510T0900Z-210510T1300Z/
Beadle-Kingsbury-Brookings-Jerauld-Sanborn-Miner-Brule-Aurora-
Davison-Hanson-Douglas-
1203 AM CDT Mon May 10 2021

...FROST ADVISORY REMAINS IN EFFECT FROM 4 AM TO 8 AM CDT
MONDAY...

* WHAT...Temperatures as low as 33 will result in frost 
  formation.

* WHERE...Portions of central, east central, south central and 
  southeast South Dakota.

* WHEN...From 4 AM to 8 AM CDT Monday.

* IMPACTS...Frost could kill sensitive outdoor vegetation if 
  left uncovered.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps to protect tender plants from the cold.

&&

$$

For more information from the National Weather Service visit
https://weather.gov/siouxfalls
719 
WWUS73 KFSD 101307
NPWFSD

URGENT - WEATHER MESSAGE
National Weather Service Sioux Falls SD
807 AM CDT Mon May 10 2021

SDZ038>040-052>054-057>060-064-101415-
/O.EXP.KFSD.FR.Y.0004.000000T0000Z-210510T1300Z/
Beadle-Kingsbury-Brookings-Jerauld-Sanborn-Miner-Brule-Aurora-
Davison-Hanson-Douglas-
807 AM CDT Mon May 10 2021

...FROST ADVISORY HAS EXPIRED...

Temperatures have climbed into the lower 40s, and the threat for
widespread frost has ended.

$$

For more information from the National Weather Service visit
https://weather.gov/siouxfalls

Nearby

Frost Advisories in South Dakota, 2021Every frost advisory 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.