Alert archive / Iowa / Heat Advisories in 2021

Heat Advisory 3, NWS Sioux Falls, SD

June 17, 20214 counties in Iowa; Dakota County, Nebraska

NWS Sioux Falls, SD issued this heat advisory at Jun 17, 2021, 3:00 AM CDT for 4 counties in Iowa; Dakota County, Nebraska. It took effect at Jun 17, 2021, 1:00 PM CDT. It was in force for 6 hr.

The area

The counties it named.

The facts

Issued
Jun 17, 2021, 3:00 AM CDT (08:00 UTC)
In effect from
Jun 17, 2021, 1:00 PM CDT
Expired
Jun 17, 2021, 7:22 PM CDT
In force
6 hr
Issued by
NWS Sioux Falls, SD

Counties Buena Vista County, IA, Cherokee County, IA, Ida County, IA, Woodbury County, IA, Dakota County, NE

The radar

The Sioux Falls radar (KFSD), 141 km from the middle of the area, began a volume at 08:04 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

Omaha, NE (KOAX), launched 00:00Z, 8.0 hours before the alert went out and 143 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, Omaha, NE at 00:00Z on 2021-06-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2997 joules per kilogram.LCLLFCEL10008507005003002001001 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, Omaha, NE at 00:00Z on 2021-06-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 120 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
2997 J/kg
Mixed-layer CIN
-144 J/kg
Mixed-layer LCL
1946 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
120 m²/s²
0-3 km storm-relative helicity
435 m²/s²
Significant tornado parameter
0.1
Supercell composite
27.9

Open this sounding in Storm Lab

The text

As transmitted.

361 
WWUS73 KFSD 170800
NPWFSD

URGENT - WEATHER MESSAGE
National Weather Service Sioux Falls SD
300 AM CDT Thu Jun 17 2021

IAZ021-022-031-032-NEZ014-171600-
/O.NEW.KFSD.HT.Y.0003.210617T1800Z-210618T0100Z/
Cherokee-Buena Vista-Woodbury-Ida-Dakota-
300 AM CDT Thu Jun 17 2021

...HEAT ADVISORY IN EFFECT FROM 1 PM THIS AFTERNOON TO 8 PM CDT
THIS EVENING...

* WHAT...Heat index values up to 106 expected.

* WHERE...In Nebraska, Dakota County. In Iowa, Cherokee, Buena 
  Vista, Woodbury and Ida Counties.

* WHEN...From 1 PM this afternoon to 8 PM CDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

For more information from the National Weather Service visit
https://weather.gov/siouxfalls
2 follow-up statements
690 
WWUS73 KFSD 171955
NPWFSD

URGENT - WEATHER MESSAGE
National Weather Service Sioux Falls SD
255 PM CDT Thu Jun 17 2021

IAZ021-022-031-032-NEZ014-180100-
/O.CON.KFSD.HT.Y.0003.000000T0000Z-210618T0100Z/
Cherokee-Buena Vista-Woodbury-Ida-Dakota-
255 PM CDT Thu Jun 17 2021

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 8 PM CDT THIS EVENING...

* WHAT...Heat index values up to 106 expected.

* WHERE...In Nebraska, Dakota County. In Iowa, Cherokee, Buena 
  Vista, Woodbury and Ida Counties.

* WHEN...From 1 PM this afternoon to 8 PM CDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

For more information from the National Weather Service visit
https://weather.gov/siouxfalls
625 
WWUS73 KFSD 180022
NPWFSD

URGENT - WEATHER MESSAGE
National Weather Service Sioux Falls SD
722 PM CDT Thu Jun 17 2021

IAZ021-022-031-032-NEZ014-180130-
/O.CAN.KFSD.HT.Y.0003.000000T0000Z-210618T0100Z/
Cherokee-Buena Vista-Woodbury-Ida-Dakota-
722 PM CDT Thu Jun 17 2021

...HEAT ADVISORY IS CANCELLED...

Heat indices have dropped below the advisory threshold, thus 
allowing for the advisory to be cancelled early. Temperatures will
continue to slowly fall through the evening hours.

$$

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

The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 16, 8:38 PM CDTSevere Thunderstorm WarningFSDBuena Vista, Cherokee, Clay, O'Brien37 min
Jun 16, 9:00 PM CDTSevere Thunderstorm WarningFSDBuena Vista, Cherokee, Ida45 min
Jun 16, 9:47 PM CDTSevere Thunderstorm WarningFSDIda28 min
Jun 16, 10:04 PM CDTSevere Thunderstorm WarningFSDIda9 min

Nearby

Heat Advisories in Iowa, 2021Heat Advisories in Nebraska, 2021Every heat 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.