Mesoscale Discussion 0315

MESOSCALE DISCUSSION 0315
NWS STORM PREDICTION CENTER NORMAN OK
1103 AM CST SUN MAR 02 2008

AREAS AFFECTED...NWRN OK INTO S CNTRL/E CNTRL KS
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 021703Z - 021930Z

AN INCREASING RISK FOR AT LEAST ISOLATED SEVERE STORMS SEEMS
PROBABLE DURING THE 18-21Z TIME FRAME. TRENDS ARE BEING MONITORED
FOR THE POSSIBILITY OF A WW.

LATEST RUC GUIDANCE INDICATES THE LEADING EDGE OF WEAK MID-LEVEL
COOLING IS ALREADY SPREADING THROUGH WESTERN KANSAS AND OKLAHOMA.
THIS IS IN ASSOCIATION WITH AN INCREASINGLY SHEARED MID-LEVEL
IMPULSE THAT HAS EMERGED FROM THE SOUTHWESTERN STATES...AND
REFLECTED BY ONGOING DEEPENING CONVECTIVE DEVELOPMENT. THE BULK OF
CONVECTIVE ACTIVITY IS LIKELY STILL BASED ABOVE A CAPPING ELEVATED
MIXED LAYER ACROSS WESTERN OKLAHOMA...AND ABOVE AN INVERSION
ASSOCIATED WITH A SOUTHWARD SURGING COLD FRONT ACROSS WESTERN
KANSAS. BUT...STORMS NOW FORMING IN CLOSER PROXIMITY TO THE
FRONT...NEAR/SOUTH OF DODGE CITY...ARE PROBABLY ROOTED IN OR NEAR
THE BOUNDARY LAYER.

AS MID-LEVEL FORCING CONTINUES TO SHIFT EASTWARD THROUGH 18-20Z
...INCREASING/INTENSIFYING BOUNDARY LAYER BASED THUNDERSTORM
ACTIVITY APPEARS MOST PROBABLE ACROSS AREAS NEAR/WEST THROUGH NORTH
OF WICHITA. THIS IS ON THE NOSE OF BETTER LOW-LEVEL MOISTURE
RETURN...CHARACTERIZED BY MID/UPPER 50S SURFACE DEW POINTS...WHERE
MIXED LAYER CAPE IS ALREADY ON THE ORDER OF 500 J/KG. GIVEN FURTHER
DESTABILIZATION WITH ADDITIONAL SURFACE HEATING...IN THE PRESENCE OF
STRONG DEEP LAYER SHEAR...SUPERCELLS ARE POSSIBLE...WITH THE RISK
FOR LARGE HAIL/LOCALLY DAMAGING WIND GUSTS...PERHAPS AN ISOLATED
TORNADO.

EVEN IN THE WAKE OF THE LEAD MID-LEVEL IMPULSE...ADDITIONAL SEVERE
STORM DEVELOPMENT APPEARS POSSIBLE AS EARLY AS 20-21Z ACROSS PARTS
OF NORTHWEST OKLAHOMA. A SHARPENING DRY LINE/SURFACE COLD FRONT
INTERSECTION WILL PROVIDE A FOCUS...BENEATH DIFLUENT UPPER FLOW
DOWNSTREAM OF MAIN POLAR TROUGH NOW DIGGING INTO THE FOUR CORNERS
STATES.

..KERR.. 03/02/2008