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000
FXUS63 KLSX 170253
AFDLSX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ST LOUIS MO
953 PM CDT SUN JUN 16 2013

.UPDATE...
ISSUED AT 942 PM CDT SUN JUN 16 2013

THE PRESENCE OF A WEAK LARGE SCALE BOUNDARY EXTENDING FROM SOUTHWEST
IL THROUGH METRO ST LOUIS INTO SW MO AND A VERY UNSTABLE AIRMASS
ALLOWED FOR SCATTERED DIURNALLY DRIVEN PULSE THUNDERSTORMS TO FORM
LATE THIS AFTERNOON INTO EARLY THIS EVENING. THESE STORMS WERE
MAINLY S/SW OF ST LOUIS YET THERE CUMULATIVE OUTFLOWS HAVE ALLOWED
A CONTINUATION OF SCATTERED PULSE STORMS TO DEVELOP PROGRESSIVELY
FURTHER NORTH INSPITE OF DIMINISHING INSTABILITY. I SUSPECT THESE
STORMS WILL GRADUALLY DIMINISH IN COVERAGE OVER THE NEXT FEW
HOURS...BUT THE PRESENCE OF THE WEAK Q-STNRY BOUNDARY WILL
SUPPORT A CHANCE OF THUNDERSTORMS THROUGH THE OVERNIGHT HOURS.

AT THIS TIME IT APPEARS ANY MCS THREAT THROUGH THE OVERNIGHT HOURS
WILL REMAIN TO THE WEST OF THE CWA. AN MCS OVER WESTERN KS AND
ANOTHER MOVING SEWD OUT OF CENTRAL NEBRASKA SHOULD TRACK SEWD
THROUGH KS AND OK WITH POSSIBLY SOME NEW ACTIVITY SKIRTING WESTERN
MO.

GLASS

&&

.SHORT TERM...(TONIGHT THROUGH WEDNESDAY)
ISSUED AT 252 PM CDT SUN JUN 16 2013

EYES FOCUSED TO OUR WEST WHERE ONE OR MORE MCS WILL DEVELOP
TONIGHT AND TRACK SOUTHEAST TOWARD THE LOWER MISSOURI RIVER
VALLEY AND OZARKS REGION AFTER 06Z. SHORT TERM MODEL GUIDANCE IS
REALLY ALL OVER THE PLACE IN REGARDS TO PLACEMENT AND TRACK OF
THESE SYSTEMS. GENERALLY HAVE RAMPED UP POPS AFTER 06Z...THINKING
THAT THERE MAY BE SOME CONVECTION DEVELOPING ON THE WARM ADVECTION
WING AHEAD OF THE APPROACHING MCS. HAVE MAINTAINED LIKELY POPS
ACROSS THE SOUTHERN HALF OF THE CWA ON MONDAY AS WEAKENING
CONVECTIVE SYSTEM OR REMNANT CIRCULATION MOVES EAST ACROSS THE
CWA.

SURFACE HIGH PRESSURE WILL THEN BUILD SOUTH INTO THE REGION
ON TUESDAY AND WEDNESDAY WITH SLIGHTLY BELOW AVERAGE TEMPERATURES
A DRY CONDITIONS EXPECTED.

CVKING

.LONG TERM...(THURSDAY THROUGH NEXT SUNDAY)
ISSUED AT 252 PM CDT SUN JUN 16 2013

A TRANSITION FROM A RELATIVELY COOL NORTHWEST FLOW ALOFT TO A
MORE SUMMER LIKE UPPER LEVEL RIDGE BUILDING INTO THE MID SECTION
OF THE COUNTRY WILL TAKE PLACE. COULD SEE A COUPLE CHANCES OF
THUNDERSTORMS THURSDAY AND FRIDAY BEFORE THE RING OF FIRE LIFTS
NORTH OF THE CWA. OTHERWISE...AFTERNOON HIGH TEMPERATURES WILL
RISE INTO THE 90S BY NEXT WEEKEND.

CVKING

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 644 PM CDT SUN JUN 16 2013

WEAK FRONTAL BOUNDARY ACROSS FORECAST AREA TO REMAIN OVER REGION
THROUGH FORECAST PERIOD. LIGHT AND VARIABLE WINDS WITH PLENTY OF
LOW LEVEL MOISTURE...SO SOME PATCHY FOG/MVFR VSBYS POSSIBLE OVERNIGHT.
OTHERWISE...STILL HARD TO PIN DOWN PCPN CHANCES...TAFS TO REMAIN
DRY THROUGH FORECAST PERIOD...EXCEPT FOR KCOU. BELIEVE THEY WILL
BE ON EASTERN FRINGES OF MCS THAT DEVELOPS OVER KS TONIGHT...SO
KEPT VCTS MENTION IN TAF AFTER 15Z MONDAY.

SPECIFICS FOR KSTL...WEAK FRONTAL BOUNDARY ACROSS FORECAST AREA TO
REMAIN OVER REGION THROUGH FORECAST PERIOD. LIGHT AND VARIABLE
WINDS WITH PLENTY OF LOW LEVEL MOISTURE...SO SOME PATCHY FOG/MVFR
VSBYS POSSIBLE BETWEEN 09Z-13Z MONDAY. OTHERWISE...STILL HARD TO PIN
DOWN PCPN CHANCES...TAF TO REMAIN DRY THROUGH FORECAST PERIOD.

BYRD

&&

.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&

$$

WFO LSX