SPC MD 1650

MD 1650 CONCERNING SEVERE POTENTIAL…WATCH POSSIBLE FOR SERN NEB…NERN KS…SWRN IA AND NWRN MO

MESOSCALE DISCUSSION 1650
NWS STORM PREDICTION CENTER NORMAN OK
0836 PM CDT SAT AUG 08 2015

AREAS AFFECTED...SERN NEB...NERN KS...SWRN IA AND NWRN MO

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 090136Z - 090330Z

PROBABILITY OF WATCH ISSUANCE...40 PERCENT

SUMMARY...THUNDERSTORMS ARE EXPECTED TO INCREASE IN COVERAGE THIS
EVENING INITIALLY OVER SERN NEB...BUT EVENTUALLY INTO SWRN IA AND
POSSIBLY NERN KS AND NWRN MO. ISOLATED STRONG TO DAMAGING WIND GUSTS
AND SOME HAIL WILL BE THE MAIN THREATS. TRENDS WILL CONTINUE TO BE
MONITORED...AND A WW ISSUANCE MIGHT BE NEEDED IF STORMS BEGIN TO
SHOW SIGNS OF BECOMING BETTER ORGANIZED.

DISCUSSION...THUNDERSTORMS HAVE INITIATED OVER SERN NEB WITH A FEW
SHOWERS ALSO INCREASING OVER SWRN IA. THIS ACTIVITY APPEARS TO BE
DEVELOPING IN RESPONSE TO ASCENT RESULTING FROM A STRENGTHENING SWLY
LLJ THAT IS INTERACTING WITH A NW-SE ORIENTED BAROCLINIC ZONE. RUC
ANALYSIS ALSO INDICATES A WEAK VORT MAX CRESTING UPPER RIDGE AND
MOVING EWD THROUGH CNTRL NEB. OBJECTIVE ANALYSIS AND 00Z RAOB DATA
SHOW THE ATMOSPHERE TO BE MODERATELY UNSTABLE IN THIS REGION.
HOWEVER BOTH THE 00Z OMAHA AND TOPEKA RAOBS SHOW CAPPING INVERSIONS
THAT ALSO INDICATE SFC-BASED CONVECTIVE INHIBITION WILL INCREASE
SUBSTANTIALLY WITH ONSET OF NOCTURNAL COOLING. STORMS THAT ARE NOW
DEVELOPING OVER SERN NEB ARE PROBABLY ELEVATED ABOVE THE INVERSION
WHICH LOWERS CONFIDENCE THAT THIS ACTIVITY WILL BE ABLE TO TAP INTO
THE HIGHER THETA-E AIR CLOSER TO THE SFC LAYER. NEVERTHELESS STORMS
MIGHT EVENTUALLY CONSOLIDATE INTO AN MCS WITH AN ATTENDANT COLD POOL
WHICH COULD INCREASE THE POTENTIAL FOR A DAMAGING WIND THREAT.

TOP VWP SHOWS FAIRLY LARGE 0-1 KM HODOGRAPHS IN ASSOCIATION WITH THE
STRENGTHENING LLJ. WHILE DEEP-LAYER VERTICAL WIND PROFILES WITH
35-40 KT 0-6 KM SHEAR SUGGESTS SOME SUPERCELL STRUCTURES WILL BE
POSSIBLE EARLY IN THE INITIATION ZONE...PRIMARY TREND SHOULD BE FORE
STORMS TO MERGE AND CONSOLIDATE. THIS ALONG WITH THE LIKELY SLIGHTLY
ELEVATED NATURE OF THE STORMS SUGGEST TORNADO THREAT SHOULD REMAIN
SOMEWHAT LIMITED...THROUGH A TORNADO OR TWO CANNOT BE RULED OUT.

..DIAL/THOMPSON.. 08/09/2015

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

ATTN...WFO...DMX...EAX...OAX...TOP...

LAT...LON   40089485 39719640 41079654 41699521 41049359 40449369
            40089485 

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from SPC Mesoscale Discussions http://1.usa.gov/1J3rqhK