Alert archive / South Dakota / Frost Advisories in 2021

Frost Advisory 2, NWS Sioux Falls, SD

May 5, 202122 counties in South Dakota; 7 counties in Minnesota; Lyon County, Iowa

NWS Sioux Falls, SD issued this frost advisory at May 5, 2021, 2:24 PM CDT for 22 counties in South Dakota; 7 counties in Minnesota; Lyon County, Iowa. It took effect at May 6, 2021, 3:00 AM CDT. It was in force for 5 hr.

The area

The counties it named.

The facts

Issued
May 5, 2021, 2:24 PM CDT (19:24 UTC)
In effect from
May 6, 2021, 3:00 AM CDT
Expired
May 6, 2021, 8:00 AM CDT
In force
5 hr
Issued by
NWS Sioux Falls, SD
All 30 counties

Lyon County, IA, Cottonwood County, MN, Lincoln County, MN, Lyon County, MN, Murray County, MN, Nobles County, MN, Pipestone County, MN, Rock County, MN, Aurora County, SD, Beadle County, SD, Bon Homme County, SD, Brookings County, SD, Brule County, SD, Charles Mix County, SD, Davison County, SD, Douglas County, SD, Gregory County, SD, Hanson County, SD, Hutchinson County, SD, Jerauld County, SD, Kingsbury County, SD, Lake County, SD, Lincoln County, SD, McCook County, SD, Miner County, SD, Minnehaha County, SD, Moody County, SD, Sanborn County, SD, Turner County, SD, Yankton County, SD

The radar

The Sioux Falls radar (KFSD), 50 km from the middle of the area, began a volume at 19:26 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, 7.4 hours before the alert went out and 154 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 2021-05-05Temperature 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 2021-05-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 158 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
1958 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
158 m²/s²
0-3 km storm-relative helicity
195 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

643 
WWUS73 KFSD 051924
NPWFSD

URGENT - WEATHER MESSAGE
National Weather Service Sioux Falls SD
224 PM CDT Wed May 5 2021

IAZ001-MNZ071-072-080-081-089-097-098-SDZ038>040-050-052>069-
060330-
/O.NEW.KFSD.FR.Y.0002.210506T0800Z-210506T1300Z/
Lyon-Lincoln-Murray-Cottonwood-Nobles-Pipestone-Rock-Beadle-
Kingsbury-Brookings-Gregory-Jerauld-Sanborn-Miner-Lake-Moody-
Brule-Aurora-Davison-Hanson-McCook-Minnehaha-Charles Mix-Douglas-
Hutchinson-Turner-Bon Homme-Yankton-
224 PM CDT Wed May 5 2021

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

* WHAT...Temperatures in the mid to lower 30s will result in 
  frost formation.

* WHERE...Portions of central, east central, south central and 
  southeast South Dakota, northwest Iowa and southwest 
  Minnesota. This includes the Tribal Lands of the Yankton Sioux 
  Tribal Nation and the Flandreau Santee Sioux Tribal Nation.

* WHEN...From 3 AM to 8 AM CDT Thursday.

* 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
2 follow-up statements
316 
WWUS73 KFSD 060251
NPWFSD

URGENT - WEATHER MESSAGE
National Weather Service Sioux Falls SD
951 PM CDT Wed May 5 2021

IAZ001-MNZ071-072-080-081-089-097-098-SDZ038>040-050-052>069-
061300-
/O.CON.KFSD.FR.Y.0002.210506T0800Z-210506T1300Z/
Lyon-Lincoln-Murray-Cottonwood-Nobles-Pipestone-Rock-Beadle-
Kingsbury-Brookings-Gregory-Jerauld-Sanborn-Miner-Lake-Moody-
Brule-Aurora-Davison-Hanson-McCook-Minnehaha-Charles Mix-Douglas-
Hutchinson-Turner-Bon Homme-Yankton-
951 PM CDT Wed May 5 2021

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

* WHAT...Temperatures in the lower to mid 30s will result in 
  frost formation.

* WHERE...Portions of central, east central, south central and 
  southeast South Dakota, northwest Iowa and southwest 
  Minnesota. This includes the Tribal Lands of the Yankton Sioux 
  Tribal Nation and the Flandreau Santee Sioux Tribal Nation.

* WHEN...From 3 AM to 8 AM CDT Thursday.

* 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
921 
WWUS73 KFSD 061259
NPWFSD

URGENT - WEATHER MESSAGE
National Weather Service Sioux Falls SD
759 AM CDT Thu May 6 2021

IAZ001-MNZ071-072-080-081-089-097-098-SDZ038>040-050-052>069-
061400-
/O.EXP.KFSD.FR.Y.0002.000000T0000Z-210506T1300Z/
Lyon-Lincoln-Murray-Cottonwood-Nobles-Pipestone-Rock-Beadle-
Kingsbury-Brookings-Gregory-Jerauld-Sanborn-Miner-Lake-Moody-
Brule-Aurora-Davison-Hanson-McCook-Minnehaha-Charles Mix-Douglas-
Hutchinson-Turner-Bon Homme-Yankton-
759 AM CDT Thu May 6 2021

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

Temperatures will continue to warm through the morning hours,
therefore the Frost Advisory will be allowed to expire as
scheduled.

$$

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

Nearby

Frost Advisories in South Dakota, 2021Frost Advisories in Minnesota, 2021Frost Advisories in Iowa, 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.