Alert archive / Oklahoma / Mesoscale Discussions in 2016

Mesoscale Discussion 573

May 9, 201610 counties in Arkansas; 18 counties in Oklahoma; 5 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 9, 2016, 5:49 PM CDT for 10 counties in Arkansas; 18 counties in Oklahoma; 5 counties in Texas. It was in force for 56 min.

The area

The outline as issued.

The facts

Issued
May 9, 2016, 5:49 PM CDT (22:49 UTC)
Expired
May 9, 2016, 6:45 PM CDT
In force
56 min
Issued by
the Storm Prediction Center
All 33 counties

Crawford County, AR, Hempstead County, AR, Howard County, AR, Little River County, AR, Montgomery County, AR, Pike County, AR, Polk County, AR, Scott County, AR, Sebastian County, AR, Sevier County, AR, Atoka County, OK, Bryan County, OK, Choctaw County, OK, Coal County, OK, Haskell County, OK, Hughes County, OK, Johnston County, OK, Latimer County, OK, LeFlore County, OK, McCurtain County, OK, McIntosh County, OK, Muskogee County, OK, Okfuskee County, OK, Pittsburg County, OK, Pontotoc County, OK, Pushmataha County, OK, Seminole County, OK, Sequoyah County, OK, Bowie County, TX, Delta County, TX, Fannin County, TX, Lamar County, TX, Red River County, TX

The radar

The Western Arkansas radar (KSRX), 144 km from the middle of the area, began a volume at 22:49 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Norman, OK (KOUN), launched 12:00Z, 10.8 hours before the alert went out and 188 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 2016-05-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 686 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 2016-05-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 66 square meters per square second.1939587897117Sfc1 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
686 J/kg
Mixed-layer CIN
-97 J/kg
Mixed-layer LCL
620 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
66 m²/s²
0-3 km storm-relative helicity
336 m²/s²
Significant tornado parameter
0.5
Supercell composite
6.0

Open this sounding in Storm Lab

The text

As transmitted.

474 
ACUS11 KWNS 092249
SWOMCD
SPC MCD 092249 
ARZ000-TXZ000-OKZ000-092345-

MESOSCALE DISCUSSION 0573
NWS STORM PREDICTION CENTER NORMAN OK
0549 PM CDT MON MAY 09 2016

AREAS AFFECTED...SOUTH-CENTRAL/SOUTHEAST OK AND FAR NORTH TX TO AR

CONCERNING...TORNADO WATCH 155...

VALID 092249Z - 092345Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 155 CONTINUES.

SUMMARY...ASIDE FROM LARGE HAIL...A TORNADO RISK WILL CONTINUE
PARTICULARLY OVER THE NEXT 1-2 HOURS /POTENTIALLY THROUGH AT LEAST
00-01Z/ ACROSS CENTRAL/SOUTH-CENTRAL OK INTO SOUTHEAST OK AND
POSSIBLY EAST-CENTRAL OK. TORNADO WATCH 155 CONTINUES UNTIL 02Z/9PM
CDT.

DISCUSSION...FOUR DISTINCT SUPERCELLS ARE ONGOING ACROSS
SOUTH-CENTRAL/CENTRAL OK ROUGHLY 35-40 MILES EAST OF I-35 AS OF 530
PM CDT...WITH THE MOST PROMINENT SUPERCELL WITH A HISTORY OF A
TORNADO AND HIGHER-END VELOCITY SIGNATURE CURRENTLY SHOWING A
WEAKENING TREND ACROSS PONTOTOC COUNTY OK. AFTER INITIATING NEAR THE
DRYLINE...THESE STORMS ARE LIKELY THRIVING IN A
BAROCLINICITY/VORTICITY-RICH ENVIRONMENT AIDED BY EARLY-DAY
PRECIPITATION/RESIDUAL CLOUD COVER. ENVIRONMENT 0-1 KM SRH IS LIKELY
IN EXCESS OF 250 M2/S2 PARTICULARLY ACROSS SOUTH-CENTRAL/SOUTHEAST
OK AS SUBSTANTIATED BY KTLX WSR-88D VWP DATA AND CONTEMPORARY
MODIFICATIONS TO THE 18Z OBSERVED NORMAN SOUNDING. ACCORDINGLY...THE
TORNADO THREAT SHOULD CONTINUE PARTICULARLY FROM SOUTH-CENTRAL INTO
SOUTHEAST OK. THIS CORRIDOR IS OBSERVATIONALLY CONSISTENT WITH
REGIONALLY MAXIMIZED PRESSURE FALLS...A CONTINUED TENDENCY FOR A
BACKING OF LOW-LEVEL WINDS....AND WARMER AIR ACROSS FAR SOUTHEAST OK
AND ADJACENT ARKLATEX /SOMEWHAT COOLER TEMPERATURES AND THICKER
CLOUD COVER HAS PERSISTED ACROSS PARTS OF EAST-CENTRAL AND NORTHEAST
OK/.

..GUYER.. 05/09/2016

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...LZK...SHV...TSA...FWD...OUN...

LAT...LON   34679677 35559689 35729410 34749348 33479370 33359620
            33449664 34679677

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 9, 1:39 PM CDTMesoscale DiscussionSPCHoward, Little River, Montgomery, Polk, Scott, Sebastian and 1 more66 min
May 9, 2:36 PM CDTTornado WatchSPCCrawford, Hempstead, Howard, Little River, Miller, Montgomery and 5 more7 hr
May 9, 6:38 PM CDTMesoscale DiscussionSPCBaxter, Clay, Cleburne, Conway, Craighead, Fulton and 13 more97 min
May 8, 7:01 PM CDTMesoscale DiscussionSPCAlfalfa, Blaine, Caddo, Canadian, Comanche, Cotton and 16 more89 min
May 9, 2:39 AM CDTMesoscale DiscussionSPCCarter, Comanche, Cotton, Jefferson, Johnston, Love and 4 more3 hr
May 9, 1:46 PM CDTMesoscale DiscussionSPCAdair, Alfalfa, Canadian, Cherokee, Craig, Creek and 22 more59 min
May 9, 2:07 PM CDTSevere Thunderstorm WatchSPCAdair, Alfalfa, Blaine, Canadian, Cherokee, Cleveland and 31 more10 hr
May 9, 5:29 PM CDTMesoscale DiscussionSPCAdair, Alfalfa, Blaine, Caddo, Canadian, Cherokee and 35 more61 min
May 8, 8:01 PM CDTMesoscale DiscussionSPCBrown, Callahan, Coke, Coleman, Concho, Cooke and 29 more89 min
May 9, 5:13 PM CDTMesoscale DiscussionSPCAnderson, Angelina, Camp, Cass, Cherokee, Ellis and 25 more92 min

Nearby

Mesoscale Discussions in Oklahoma, 2016Mesoscale Discussions in Arkansas, 2016Mesoscale Discussions in Texas, 2016Every mesoscale discussion in 2016

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.