Alert archive / Arkansas / Heat Advisories in 2021

Heat Advisory 9, NWS Little Rock, AR

August 21, 202123 counties in Arkansas

NWS Little Rock, AR issued this heat advisory at Aug 21, 2021, 3:11 AM CDT for 23 counties in Arkansas. It took effect at Aug 21, 2021, 12:00 PM CDT. It was in force for 7 hr.

The area

The counties it named.

The facts

Issued: Aug 21, 2021, 3:11 AM CDT (08:11 UTC)
In effect from: Aug 21, 2021, 12:00 PM CDT
Expired: Aug 21, 2021, 7:00 PM CDT
In force: 7 hr
Issued by: NWS Little Rock, AR

All 23 counties

Arkansas County, AR, Bradley County, AR, Calhoun County, AR, Clark County, AR, Cleveland County, AR, Conway County, AR, Dallas County, AR, Desha County, AR, Drew County, AR, Faulkner County, AR, Garland County, AR, Grant County, AR, Hot Spring County, AR, Jefferson County, AR, Lincoln County, AR, Lonoke County, AR, Monroe County, AR, Ouachita County, AR, Perry County, AR, Pike County, AR, Prairie County, AR, Pulaski County, AR, Saline County, AR

The radar

The Little Rock radar (KLZK), 60 km from the middle of the area, began a volume at 08:15 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

Little Rock, AR (KLZK), launched 00:00Z, 8.2 hours before the alert went out and 225 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1267 J/kg
Mixed-layer CIN: -15 J/kg
Mixed-layer LCL: 1206 m above ground
0-6 km bulk shear: 13 kt
0-1 km storm-relative helicity: 49 m²/s²
0-3 km storm-relative helicity: 104 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this heat advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Little Rock, AR wrote its last area forecast discussion before this heat advisory went out at Aug 21, 12:08 AM CDT, 3 hours 3 minutes earlier.

Area forecast discussion, Aug 21, 12:08 AM CDT, 3 hours 3 minutes before

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Hazardous weather outlook, Aug 20, 3:35 AM CDT, 23 hours 36 minutes before

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The office that day

Everything else NWS Little Rock, AR issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 21, 9:51 AM CDT	River Flood Warning	LZK	Jackson, Woodruff	7 days
Aug 21, 2:55 PM CDT	Heat Advisory	LZK	Arkansas, Bradley, Calhoun, Clark, Cleveland, Conway and 19 more	29 hr
Aug 21, 5:48 PM CDT	Special Weather Statement	LZK	Saline	27 min

Nearby

Heat Advisories in Arkansas, 2021 Every 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.