[MCD] SWOMCD

[Mesoscale Convective Discussions]

ACUS11 KWNS 231714
SWOMCD
SPC MCD 231712 
NEZ000-SDZ000-KSZ000-231845-

MESOSCALE DISCUSSION 0950
NWS STORM PREDICTION CENTER NORMAN OK
1212 PM CDT TUE MAY 23 2006

AREAS AFFECTED...PARTS OF CENTRAL AND ERN SD INTO CENTRAL AND ERN
NEB

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 231712Z - 231845Z

THUNDERSTORMS ARE FORECAST TO DEVELOP BY 19-20Z ACROSS CENTRAL
PORTIONS OF SD AND NEB.  WW WILL LIKELY BE REQUIRED IN THE NEXT 1 TO
2 HOURS.

LATEST SURFACE ANALYSIS SHOWS LOW TO MID 60S DEWPOINTS IN A N-S AXIS
ACROSS THE ERN HALVES OF SD AND NEB...AHEAD OF WEAK
TROUGH/CONVERGENCE ZONE WITHIN DESTABILIZING WARM SECTOR.

STRONG HEATING WILL CONTINUE ACROSS THIS REGION AS MID-LEVEL DRY
SLOT CONTINUES SPREADING NEWD -- AHEAD OF CIRCULATION CENTER ALOFT
NOW OVER NERN WY/W CENTRAL SD. THOUGH AIRMASS REMAINS CAPPED
ATTM...CONTINUED HEATING AND PERSISTENT LARGE-SCALE UVV WILL COMBINE
TO WEAKEN CAP...LIKELY RESULTING IN THUNDERSTORM DEVELOPMENT BY
MID-AFTERNOON.

ALONG WITH INCREASING INSTABILITY...WIND FIELD IS BECOMING MORE
FAVORABLE WITH TIME AS STRONGER SWLY FLOW ALOFT SPREADS EWD ATOP
LOW-LEVEL SLYS -- RESULTING IN VEERING/SHEARED PROFILES SUPPORTIVE
OF SEVERE/SUPERCELL STORMS.  THUS...EXPECT DEVELOPING UPDRAFTS TO
RAPIDLY INTENSIFY/ACQUIRE ROTATION.  THOUGH LOW-LEVEL SHEAR WILL BE
SUPPORTIVE OF TORNADOES...RELATIVELY DEEP MIXED LAYER SHOULD LIMIT
OVERALL TORNADO POTENTIAL.  LARGE HAIL SHOULD INITIALLY BE THE
PRIMARY SEVERE THREAT...AS CELLULAR CONVECTION IS ANTICIPATED THIS
AFTERNOON.  WITH A MORE LINEAR CONVECTIVE MODE FORECAST TO EVOLVE
WITH TIME...THREAT FOR DAMAGING WINDS SHOULD ALSO INCREASE.

..GOSS.. 05/23/2006

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

ATTN...WFO...FSD...OAX...TOP...ABR...GID...LBF...UNR...

45259924 45059837 43979709 42629676 40729695 39999759
39929939 41549948 43179980 45360096