Mesoscale Discussion 556

Issued

May 8, 2016, 1:18 PM CDT (18:18 UTC)

Expired

May 8, 2016, 3:15 PM CDT

In force

117 min

Issued by

the Storm Prediction Center

Chance of a watch

95%

The Altus AFB radar (KFDR), 116 km from the middle of the area, began a volume at 18:18 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.

• Severe Thunderstorm Watch 148May 8, 1:45 PM CDT
• Tornado Watch 149May 8, 3:05 PM CDT
• Tornado Watch 150May 8, 3:45 PM CDT

703 
ACUS11 KWNS 081819
SWOMCD
SPC MCD 081818 
OKZ000-TXZ000-KSZ000-082015-

MESOSCALE DISCUSSION 0556
NWS STORM PREDICTION CENTER NORMAN OK
0118 PM CDT SUN MAY 08 2016

AREAS AFFECTED...PORTIONS OF N TX AND WRN OK

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 

VALID 081818Z - 082015Z

PROBABILITY OF WATCH ISSUANCE...95 PERCENT

SUMMARY...STORMS ARE EXPECTED TO INITIATE ALONG THE DRYLINE ACROSS
SW OK BY 21Z. ADDITIONAL STORM WILL DEVELOP OVER NW OK AND MOVE INTO
S-CNTRL KS AS WELL. VERY LARGE HAIL...A FEW TORNADOES AND DAMAGING
WIND GUSTS WILL BE POSSIBLE AND A TORNADO WATCH WILL LIKELY BE
NEEDED IN THE NEXT 1-2 HOURS.

DISCUSSION...LOW LEVEL CUMULUS FIELD CONTINUES TO EXPEND FROM NEAR
THE RED RIVER THROUGH WESTERN OK THIS AFTERNOON. THE NATURE OF THE
CU SUGGESTS INHIBITION STILL EXISTS. BUT EXPECT INITIATION BY THE
20-21Z TIME FRAME ACROSS WESTERN N TX INTO SOUTHWEST OK WHERE
HEATING HAS BEEN STRONGEST AND TEMPS ARE IN THE LOW 80S AS OF 18Z.
SURFACE DEWPOINTS ARE HOVERING IN THE 62-66 DEG F RANGE ACROSS MUCH
OF THE MCD AREA EXCEPT PORTIONS OF FAR NW OK INTO S-CNTRL KS WHERE
UPPER 50S AND LOW 60S WERE NOTED...RESULTING IN MUCAPE RANGING FROM
1000-2000 J/KG. DEEP LAYER SHEAR PROFILES WILL FAVOR SUPERCELLS.
MIDLEVEL LAPSE RATES GREATER THAN 7.5 DEG C/KM PER OBJECTIVE
ANALYSIS WILL SUPPORT VERY LARGE HAIL /SOME BIGGER THAN 2 INCHES/.
SPEED SHEAR IN THE LOWEST 1-2 KM IS CURRENTLY UNIMPRESSIVE BUT
SHOULD IMPROVE IN THE 22-00Z TIME FRAME IN VICINITY OF THE BULGING
DRYLINE. AS SUCH...A FEW HOURS OF INCREASED TORNADO POTENTIAL WITH
ISOLATED DISCRETE CONVECTION WILL EXIST ACROSS SW OK.  

ADDITIONAL STORMS ARE EXPECTED TO DEVELOP LATER THIS AFTERNOON
ACROSS NW OK AND MOVE INTO S-CNTRL KS. THESE STORMS WILL EXIST IN A
SIMILAR BACKGROUND ENVIRONMENT AS THOSE FURTHER S OVER SW OK...BUT
QUALITY OF LOW LEVEL MOISTURE AND INSTABILITY DIMINISHES INTO
S-CNTRL KS WHERE ONGOING SHOWERS AND THUNDERSTORMS HAVE PERSISTED
MOST OF THE DAY. STORM COVERAGE AND INTENSITY IS A BIT MORE
UNCERTAIN IN THIS AREA...THOUGH A WATCH WILL LIKELY BE NEEDED LATER
THIS AFTERNOON AS WELL.

..LEITMAN/HART.. 05/08/2016

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

ATTN...WFO...ICT...FWD...OUN...DDC...SJT...LUB...AMA...

LAT...LON   37499805 37089770 36679751 36099747 35019741 33769741
            33439746 33149771 33109785 33049883 33229940 33509976
            33939994 35030003 36360009 36759992 37129970 37449924
            37599866 37499805

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

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.