000 FXUS63 KICT 281050 AFDICT AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WICHITA KS 550 AM CDT SAT JUL 28 2007 .UPDATE... .AVIATION... 12Z TAF SET: TODAY: WIDELY SCT TSRA MAY REDEVELOP OVER PRIMARILY CENTRAL KS LATE THIS AFTERNOON ALONG...AND NORTH...OF A NEARLY STATIONARY FRONT. SPARSE & SPORADIC NATURE OF THE CONVECTION DICTATES VCTS ASSIGNMENT TO KRSL & KSLN TERMINALS EFFECTIVE 20-21Z. VFR CATEGORIES TO PREVAIL AT ALL TERMINALS WITH SCT CUMULUS DEVELOPING 3,500 FEET BY 18Z. LATE TONIGHT: MCS DEVELOPMENT VERY POSSIBLE OVER KS/NEBRASKA BORDER WITH COMPLEX FORECAST TO MOVE SE OVER KRSL & KSLN TERMINALS 05Z ONWARD. HAVE MAINTAINED VCTS ASSIGNMENT TO BOTH TERMINALS UNTIL LOCATION AND BEHAVIOR OF MCS COMES INTO BETTER FOCUS. && .PREV DISCUSSION... /ISSUED 307 AM CDT SAT JUL 28 2007/ DISCUSSION... FORECAST CONCERNS ARE STORM CHANCES THIS AFTERNOON AND TONIGHT...AND CHANCES FOR THE REST OF THE WEEKEND. TODAY-TONIGHT: SURFACE BOUNDARY CONTINUES TO MAKE SLOW PROGRESS INTO SOUTH CENTRAL AND SOUTHEAST KS AS THIS TIME. PRESSURE FALLS SUGGEST THAT PORTION OF THE FRONT OVER ERN KS IS MAKING MORE PROGRESS THAN CEN KS SECTION. LACK OF ANY LIFT OVER THE TOP OF THE BOUNDARY HAS KEPT ANY CONVECTION FROM DEVELOPING EARLY TODAY. QUESTION LATER TODAY IS WHERE THIS FRONTAL BOUNDARY WILL END UP TODAY...WITH CONVERGENCE INCREASING ENOUGH FOR SCATTERED STORMS BY LATE THIS AFTERNOON. WARM MID LEVEL TEMPS WILL KEEP THINGS INITIALLY CAPPED ESPECIALLY WEST OF INTERSTATE 135. SO WILL GO WITH HIGHEST CHANCE POPS BASICALLY FROM CNU TO SLN. MLCAPE VALUES AROUND 2500 J/KG POOLING JUST TO THE SOUTH OF BOUNDARY SUGGESTS SOME STRONG STORMS...BUT A WEAK SHEARED ENVIRONMENT WILL KEEP STORMS FROM BECOMING SEVERE WITH SLOW MOVING STORMS POSSIBLY PRODUCING LOCALLY HEAVY RAINFALL. MOISTURE TRANSPORT AND FN-CONVERGENCE ALONG THE FRONTAL BOUNDARY INCREASES ACROSS NW KS INTO CENTRAL KS BY AROUND 06Z/SUN. THIS CONVERGENCE WILL PROBABLY LEAD TO A CONVECTIVE COMPLEX ORGANIZING ACROSS CEN KS...SO WILL KEEP A SOLID CHANCE TO LIKELY POP IN THIS AREA TONIGHT. WILL BUMP UP POPS TOWARDS SOUTH CENTRAL KS LATE TONIGHT AS FAVORABLE THICKNESS VALUES SUGGEST PROPAGATION WILL TAKE THIS COMPLEX SOUTH-SOUTHEAST. MODELS DO SHOW SOME DECENT 0-3KM BULK SHEAR VALUES WHICH SUGGESTS SOME DOWNBURST WIND POTENTIAL EARLY IN ITS LIFE CYCLE. SUNDAY-SUNDAY NIGHT COULD SEE SOME CONVECTION ON-GOING DURING THE START OF THIS TIME FRAME...AS CONVECTIVE COMPLEX IS EXPECTED TO MOVE INTO SOUTH CENTRAL KANSAS EARLY ON SUNDAY. NOT QUITE SURE HOW FAR SOUTH THIS CONVECTION WILL MAKE IT AS IT MOVES SOUTH INTO AN AREA OF WARMER MID LEVEL TEMPS. CORFIDI VECTORS ALSO SUGGEST THAT FORWARD PROPAGATION INTO OK WILL BE LIMITED. SO CONVECTION COULD COME TO SOUTH CENTRAL KS TO DIE. OUTFLOW BOUNDARIES LEFT OVER FROM THIS CONVECTION AND REMNANTS OF THE FRONTAL BOUNDARY DRAPED FROM GENERALLY PPF-ICT-HYS WILL LEAD TO SOME MORE TSRA REDEVELOPING WITH THE DIURNAL HEATING OF THE DAY. SO WILL KEEP A CHANCE POP AROUND FOR THIS. MOISTURE TRANSPORT AND FN-CONVERGENCE COULD ALSO LEAD TO ANOTHER CONVECTIVE COMPLEX DEVELOPING JUST TO THE WEST OF THE FORECAST AREA. MODELS DIFFER ON WHERE THIS CONVECTION WILL DEVELOP...WITH GFS FURTHER EAST NEAR CENTRAL KS WHILE NAM IS FURTHER WEST. SO WILL ONLY GO WITH A SLIGHT CHANCE FOR NOW...BUT COULD SEE THIS POP GO HIGHER IF GFS REMAINS CONSISTENT. MON-TUE: MODELS CONTINUE SUGGEST THAT WEAK BOUNDARY COULD REMAIN STATIONARY FOR MON WITH STORM CHANCES AGAIN ON MON AS EASTERLY UPSLOPE FLOW LEADS TO ENHANCED CONVERGENCE. CONFIDENCE IN HOW THIS WILL PLAY OUT IS RATHER LOW...SO WILL KEEP POPS IN THE CHANCE CATEGORY FOR NOW THROUGH MON NIGHT. WILL LEAVE TUE DRY FOR NOW...BUT LATEST GFS SUGGESTS THAT BOUNDARY REMNANTS WILL REMAIN AROUND FOR TUE AS WELL. WED-FRI: MEDIUM RANGE MODELS SUGGEST THAT UPPER RIDGE WILL CONTINUE TO BREAK DOWN FOR THE END OF THE WEEK...WITH MORE OF A ZONAL FLOW PATTERN. THIS SUGGESTS A MORE ACTIVE WEATHER PATTERN FOR KS. OPERATIONAL GFS SUGGESTS THAT ANOTHER WEAK UPPER LOW COULD PARK ITSELF ACROSS KS FOR THIS TIME FRAME...BUT THIS IS THE FIRST MODEL RUN TO SHOW THIS...SO WILL KEEP THIS DRY FOR NOW BUT WOULD NOT BE SURPRISED TO SEE POPS ENTERED INTO THE FORECAST LATER. AVIATION... 06Z TAFS...NEARLY STATIONARY BOUNDARY OVER CENTRAL KANSAS MAY SLOWLY DRIFT SOUTHWARD...ALBEIT NOT MUCH BEFORE SATURDAY MORNING. CONVECTION SHOULD REMAIN NORTH AND EAST OF KRSL AND KSLN THROUGH THE NIGHT...HOWEVER WITH THE BOUNDARY NEARBY CONFIDENCE IS LOW ON TIMING THAT THUNDERSTORMS WILL AFFECT THESE SITES (AS WELL AS KHUT...KICT...AND KCNU). IF SKIES CLEAR OUT AT KRSL TONIGHT...THERE COULD BE SOME MVFR VISIBILITIES IN THE AREA DUE TO FOG. BOUNDARY IS EXPECTED TO EVENTUALLY MAKE IT SOUTH OF THE KANSAS BORDER BY LATE SATURDAY OR EARLY SUNDAY. UPDATED AVIATION DISCUSSION WITH 12Z TAF ISSUANCE. SCHRECK && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 91 71 89 68 / 30 30 40 30 HUTCHINSON 90 70 88 68 / 30 40 40 30 NEWTON 90 70 88 68 / 30 40 40 20 ELDORADO 90 70 87 68 / 30 30 40 20 WINFIELD-KWLD 91 71 90 68 / 20 30 40 30 RUSSELL 88 68 89 67 / 30 50 40 30 GREAT BEND 90 68 88 68 / 30 40 40 30 SALINA 88 69 88 67 / 30 50 40 20 MCPHERSON 89 69 88 68 / 30 40 40 20 COFFEYVILLE 90 71 89 68 / 30 20 40 20 CHANUTE 89 70 89 68 / 30 30 40 20 IOLA 89 70 89 68 / 30 30 30 20 PARSONS-KPPF 90 71 89 68 / 30 30 40 20 && .ICT WATCHES/WARNINGS/ADVISORIES... NONE. && $$