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000
FXUS63 KLSX 151148
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
648 AM CDT SAT JUN 15 2013

.SHORT TERM...(THROUGH LATE THIS AFTERNOON)
ISSUED AT 358 AM CDT SAT JUN 15 2013

WEAKENING MCS WAS DROPPING SEWD THROUGH NERN AND CNTRL MO AND W
CNTRL IL EARLY THIS MRNG.  THIS MCS SHOULD CONTINUE TO WEAKEN AS IT
MOVES INTO E CNTRL MO AND SWRN IL THIS MRNG.  IT WILL LIKELY LAY OUT
AN OUTFLOW BOUNDARY ACROSS SERN MO AND SWRN IL WHICH MAY BE THE
FOCUS FOR ADDITIONAL CONVECTION THIS AFTN AS THE ATMOSPHERE
DESTABILIZES DUE TO DAYTIME HEATING.  MUCH OF THE MID TO HIGH LEVEL
CONVECTIVE DEBRIS CLOUDS SHOULD DISSIPATE LATER THIS MRNG ALLOWING
AT LEAST PARTIAL SUNSHINE THIS AFTN AND LEADING TO HIGH TEMPERATURES
SLIGHTLY WARMER THAN YESTERDAY AND SLIGHTLY ABOVE NORMAL.

GKS

.LONG TERM...(TONIGHT THROUGH FRIDAY)
ISSUED AT 358 AM CDT SAT JUN 15 2013

(TONIGHT - MONDAY)

ACTIVE WX PATTERN WITH PLENTY OF OPPORTUNITIES FOR RAIN WILL
DOMINATE THIS PERIOD.

FLAT UPPER LEVEL FLOW OVER THE CNTRL CONUS WILL PREVAIL THRU MONDAY
AS A SERIES OF SHORTWAVES OR UPPER LEVEL DISTURBANCES PUSH THRU.
THE OVERALL TREND FOR THE TRACK OF THESE DISTURBANCES WILL BE TO
GRADUALLY TRACK PROGRESSIVELY FURTHER S THRU OUR AREA.

THE FIRST OF THESE RAIN OPPORTUNITIES OF THIS PERIOD...FOR LATE
TODAY AND INTO TONIGHT...LOOKS TO INITIALLY DEVELOP OVER SRN IA AND
NRN MO WITH APPROACH OF SRN PLAINS SHORTWAVE ROUNDING THE BACKSIDE
OF COLLAPSING RIDGE AND IN AN ATMOSPHERE FINALLY RECOVERING FROM
THIS MORNING/S CONVECTION.  THE MAIN BODY WILL LIKELY AFFECT THE NRN
FA THIS EVENING BEFORE TURNING ITS GAZE SEWD FOR THE OVERNIGHT...
MAKING ANOTHER RUN ON THE I-70 CORRIDOR MUCH LIKE WE ARE DEALING
WITH NOW.  THE LEFTOVERS OF THIS EVENT ARE EXPECTED TO LINGER INTO
SUNDAY MORNING...WITH A GENERAL LACK OF TRIGGERS IN THE AFTERNOON
BUT PROBABLY WILL HAVE SOME LINGERING BOUNDARIES...ESPECIALLY FOR
AREAS S OF I-70...TO ALLOW NEW DEVELOPMENT WITH THE HEATING OF THE
DAY.

A NEW MCS IS EXPECTED TO FORM OVER THE CNTRL PLAINS SUNDAY NIGHT AND
THEN TRACK MAINLY EWD INTO THE CNTRL-SRN FA FOR MONDAY MORNING...
ALSO ALLOWING A CDFNT THRU AS WELL.

WITH ALL OF THESE RAIN CHCS...ANY HOT TEMPS WILL BE KEPT AT BAY.
SUNDAY WILL ONLY BE A DEG OR TWO ABOVE NORMAL ON MAXES...WITH A DEG
OR TWO BELOW AVERAGE ANTICIPATED FOR MONDAY WITH EARLY RAIN AND A
CDFNT LATER.  MOS TEMPS AGAIN OVERALL LOOK TOO WARM AND SCALED BACK.

(TUESDAY - WEDNESDAY)

A RELATIVELY DRY PERIOD WILL FOLLOW WITH SFC HI PRES DOMINATING
TUESDAY AND WEDNESDAY AND NW FLOW ALOFT.  MAX TEMPS BOTH DAYS WILL
REMAIN JUST BELOW AVERAGE.

(THURSDAY - FRIDAY)

THE RESURGENT UPPER LEVEL RIDGE WILL AGAIN MAKE AN ATTEMPT AT
BUILDING OVERHEAD BY THE END OF THE WEEK...ALONG WITH ABOVE AVERAGE
TEMPS.  A SFC WRMFNT WILL MOVE THRU LATE THURSDAY AND HAVE
MAINTAINED THE CHC POPS...WITH A WARM SECTOR SETUP FOR FRIDAY AND
DRY CONDITIONS ANTICIPATED.

TES

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 556 AM CDT SAT JUN 15 2013

SHOWERS AND STORMS FROM WEAKENING MCS SHOULD MOVE OUT OF THE ST
LOUIS METRO AREA BY 13-14Z SAT. MAY HAVE SCATTERED SHOWERS AND
STORMS REDEVELOPING THIS AFTN...BUT THE BEST CHANCE FOR MORE
CONVECTION WILL LIKELY OCCUR TGT WITH THE APPROACH OF AN UPPER
LEVEL DISTURBANCE. SHOULD HAVE SCATTERED DIURNAL CUMULUS CLOUDS
LATE THIS MRNG AND AFTN ALONG WITH HIGH LEVEL CLOUDS. SLY SFC
WINDS TODAY SHOULD GRADUALLY VEER AROUND TO A SWLY DIRECTION TGT.

SPECIFICS FOR KSTL...MOST OF THE SHOWER/THUNDERSTORM ACTIVITY
SHOULD SHIFT SE OF STL BY 13Z SAT. COULD NOT RULE OUT ISOLATED TO
SCATTERED SHOWERS AND STORMS THIS AFTN AND THIS EVNG...BUT THE
BEST COVERAGE OF CONVECTION SHOULD BE LATE TGT AS ANOTHER MCS MAY
DROP SEWD TOWARDS STL FROM NRN MO. OUTSIDE THE SHOWERS/STORMS
PREVAILING CONDITIONS SHOULD BE VFR WITH MAINLY MID-HIGH LEVEL
CLOUDS ALONG WITH SCATTERED DIURNAL CUMULUS CLOUDS LATE THIS MRNG
AND AFTN. SFC WINDS WILL BECOME S-SWLY LATER THIS MRNG...THEN
VEER AROUND TO A W-SWLY DIRECTION SUN MRNG AS A WEAK FRONT/SFC
TROUGH SHIFTS SE OF STL.

GKS

&&

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

$$

WFO LSX