Alert archive / Arkansas / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 406, NWS Tulsa, OK

August 18, 1998Benton County, Arkansas

NWS Tulsa, OK issued this severe thunderstorm warning at Aug 18, 1998, 4:56 PM CDT for Benton County, Arkansas. It was in force for 34 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties.

The facts

Issued: Aug 18, 1998, 4:56 PM CDT (21:56 UTC)
Expired: Aug 18, 1998, 5:30 PM CDT
In force: 34 min
Issued by: NWS Tulsa, OK
Area: Whole counties; the outline is the Mesonet’s reconstruction

County Benton County, AR

The radar

The Springfield radar (KSGF), 117 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

Springfield, MO (KSGF), launched 12:00Z, 9.9 hours before the alert went out and 69 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: 1016 J/kg
Mixed-layer CIN: -221 J/kg
Mixed-layer LCL: 1469 m above ground
0-6 km bulk shear: 13 kt
0-1 km storm-relative helicity: 115 m²/s²
0-3 km storm-relative helicity: 142 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

357 
WUUS54 KTSA 182158 RRA
SVRTUL
ARC007-182230-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TULSA OK
456 PM CDT TUE AUG 18 1998

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR
     EASTERN BENTON COUNTY IN ARKANSAS

* UNTIL 530 PM CDT

* AT 456 PM CDT RADAR DETECTED A SEVERE THUNDERSTORM 2 MILES SOUTH OF
  SEDALIA...MOVING WEST AT 15 MILES PER HOUR.

* SOME LOCATIONS AFFECTED INCLUDE...  AVOCA...LARUE...WAR EAGLE...
  SEDALIA...LOOKOUT...LOWELL AND ROGERS

HAIL TO THE SIZE OF DIMES AND WIND GUSTS TO 60 MPH CAN BE EXPECTED IN
THE WARNED AREA.

LAT...LON 3635 9387 3642 9413 3621 9420 3621 9401
          3624 9387

What forecasters said that day

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

NWS Tulsa, OK wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 18, 3:50 PM CDT, 1 hour 6 minutes earlier.

Area forecast discussion, Aug 18, 3:50 PM CDT, 1 hour 6 minutes before

EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
350 PM CDT TUE AUG 18 1998

PATTERN LOOKING FAIRLY SIMILAR THROUGH THE SHORT RANGE FORECAST.
SYSTEMS WILL MOVE ALONG IN THE EASTERLY FLOW GENERALLY TO THE SOUTH
OF THE FORECAST AREA. THUS BELIEVE THAT MOST IF NOT ALL PRECIPITATION
WILL BE DIURNAL IN SOUTHERN AND EASTERN ZONES. WILL CONTINUE TO
MENTION ISOLATED AFTERNOON AND EVENING THUNDERSTORMS IN THESE AREAS.
ELSEWHERE IT SHOULD REMAIN DRY. LOW LEVEL FLOW GRADUALLY BECOMES MORE
EASTERLY. MAXIMUM TEMPERATURES LOOK NEARLY AS WARM ON WEDNESDAY
COMPARED TO TODAY BUT THEN DROPPED THEM JUST A LITTLE BIT BY
THURSDAY.

MEDIUM RANGE MODELS SHOW THE UPPER RIDGE ONCE AGAIN RETROGRADING INTO
THE ROCKIES DURING THE WEEKEND. THIS WILL RESULT IN WEAK NORTHWEST
FLOW DEVELOPING ACROSS EASTERN OKLAHOMA AND NORTHWEST ARKANSAS.
BELIEVE THE MEDIUM RANGE FORECAST MODEL IS OVERDONE WITH A SHORTWAVE
COMING ACROSS THE PLAINS AND SO FOR NOW WILL KEEP THE STATUS QUO WITH
A DRY FORECAST IN THE EXTENDED PERIODS.

TUL   76  97  75  95 /   0   0   0   0
FSM   71  97  70  94 /  10  10  10  10
MLC   74  98  73  95 /   0   0   0   0
BVO   72  99  71  96 /   0   0   0   0
FYV   69  94  68  92 /  10  10  10  10
IDB   70  98  69  95 /  10  10  10  10
BYV   67  94  66  91 /  10  10  10  10
MIO   72  94  71  93 /   0   0   0  10
MKO   72  97  71  95 /   0   0   0  10
F10   74  98  73  95 /   0   0
0   0
HHW   73  99  72  96 /  10  10  10  10

.TUL...
OK...NONE.
AR...NONE.

The office that day

Everything else NWS Tulsa, OK issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 18, 4:47 PM CDT	Severe Thunderstorm Warning	TSA	Washington	43 min
Aug 18, 5:53 PM CDT	Severe Thunderstorm Warning	TSA	Benton	52 min
Aug 18, 6:00 PM CDT	Flash Flood Warning	TSA	Benton	90 min

Nearby

Severe Thunderstorm Warnings in Arkansas, 1998 Every severe thunderstorm warning in 1998

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.