Alert archive / Arkansas / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 261, NWS Little Rock, AR

July 12, 2018Polk County, Arkansas

NWS Little Rock, AR issued this severe thunderstorm warning at Jul 12, 2018, 4:57 PM CDT for Polk County, Arkansas. It was in force for 36 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jul 12, 2018, 4:57 PM CDT (21:57 UTC)
Expired
Jul 12, 2018, 5:33 PM CDT
In force
36 min
Issued by
NWS Little Rock, AR
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Polk County, AR

The radar

The Western Arkansas radar (KSRX), 90 km from the middle of the area, began a volume at 21:56 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

Norman, OK (KOUN), launched 12:00Z, 10.0 hours before the alert went out and 301 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, Norman, OK at 12:00Z on 2018-07-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 942 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Norman, OK at 12:00Z on 2018-07-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 23 square meters per square second.1939Sfc1 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
942 J/kg
Mixed-layer CIN
-47 J/kg
Mixed-layer LCL
1482 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
23 m²/s²
0-3 km storm-relative helicity
0 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 11, 7:10 PM CDTSpecial Weather StatementLZKPike35 min
Jul 11, 7:18 PM CDTSevere Thunderstorm WarningLZKPike12 min
Jul 11, 7:29 PM CDTSpecial Weather StatementLZKYell46 min
Jul 12, 2:55 AM CDTHeat AdvisoryLZKArkansas, Conway, Faulkner, Garland, Grant, Hot Spring and 13 more17 hr
Jul 12, 3:06 PM CDTSpecial Weather StatementLZKGarland24 min
Jul 12, 3:12 PM CDTSpecial Weather StatementLZKSaline33 min
Jul 12, 3:25 PM CDTSevere Thunderstorm WarningLZKGarland, Hot Spring, Saline50 min
Jul 12, 3:32 PM CDTSpecial Weather StatementLZKSaline43 min
Jul 12, 3:37 PM CDTSpecial Weather StatementLZKMontgomery38 min
Jul 12, 3:40 PM CDTSevere Thunderstorm WarningLZKMontgomery35 min
Jul 12, 3:46 PM CDTSpecial Weather StatementLZKArkansas44 min
Jul 12, 3:51 PM CDTSevere Thunderstorm WarningLZKGarland, Hot Spring39 min
Jul 12, 4:10 PM CDTSpecial Weather StatementLZKHot Spring50 min
Jul 12, 4:38 PM CDTSpecial Weather StatementLZKClark52 min
Jul 12, 5:07 PM CDTSevere Thunderstorm WarningLZKPope, Yell23 min
Jul 12, 5:12 PM CDTSpecial Weather StatementLZKPike48 min
Jul 12, 5:32 PM CDTSpecial Weather StatementLZKScott28 min
Jul 12, 6:12 PM CDTSpecial Weather StatementLZKVan Buren48 min

Nearby

Severe Thunderstorm Warnings in Arkansas, 2018Every severe thunderstorm warning in 2018

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.