000
FXUS63 KLSX 151628
AFDLSX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ST LOUIS MO
1128 AM CDT SAT JUN 15 2013

.UPDATE...
ISSUED AT 1127 AM CDT SAT JUN 15 2013

WARM FRONT CURRENTLY STRETCHING FROM A WEAK AREA OF LOW PRESSURE
NEAR OMAHA SOUTHWARD TO KANSAS CITY. FURTHER SOUTH...THE FRONT IS
OBSCURED BY OUTFLOW FROM A CLUSTER OF CONVECTION NEAR KSGF THAT IS
BEING FED BY A WEAK BUT EFFECTIVE LOW LEVEL FLOW. ANOTHER CLUSTER
OF THUNDERSTORMS NEAR THE 850MB WARM FRONT CONTINUES TO PERCULATE
ACROSS CENTRAL ILLINOIS. IN BETWEEN...BROKEN CEILINGS ARE ALLOWING
TEMPERATURES TO GRADUALLY RISE INTO THE LOWER 80S ACROSS THE CWA.

ANTICIPATE AT LEAST SCATTERED THUNDERSTORMS TO DEVELOP THIS
AFTERNOON AS WARM FRONT LIFTS EAST/NORTHEAST AND SHORTWAVE ACROSS
THE PLAINS EDGES TOWARD THE LOWER MISSOURI AND MISSISSIPPI RIVER
VALLEYS. BEST CAPE/SHEAR COMBO THIS AFTERNOON AND EARLY EVENING
WILL BE ACROSS THE NORTHWEST PORTION OF THE CWA...FROM
CENTRAL/NORTHEAST MISSOURI TO WEST CENTRAL ILLINOIS. LATEST
GUIDANCE FROM SPC CONTINUES TO HIGHLIGHT THIS CORRIDOR FOR THE
HIGHEST PROBABILITIES OF SEVERE HAIL...WIND AND TORNADOES.

CVKING

&&

.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 18Z TAFS THROUGH 18Z SUNDAY)
ISSUED AT 1127 AM CDT SAT JUN 15 2013

DEBRIS CLOUDS FROM ONGOING CONVECTION TO THE SOUTHWEST AND
NORTHEAST OF THE FORECAST AREA WILL COMBINE WITH DIURNAL CUMULUS
THIS AFTERNOON TO KEEP SKY BROKEN. THUNDERSTORMS ARE EXPECTED TO
DEVELOP ACROSS CENTRAL MISSOURI THIS AFTERNOON AND MOVE
EAST/NORTHEAST AS WARM FRONT LIFTS. A FEW OF THE STORMS COULD BE
SEVERE. BEST LIKELIHOOD OF THUNDERSTORMS WILL BE AT KCOU AND KUIN.
FUTHER SOUTHEAST AT ST. LOUIS METRO TAF SITES...CHANCES ARE LOWER.
THUNDERSTORMS MAY HOLD OFF UNTIL LATER TONIGHT FOR ST. LOUIS AREA
WHEN A WEAKENING FRONT/SURFACE TROF APPROACHES FROM THE NORTH.
SOUTHWEST WIND AT 10 KTS WILL CONTINUE TODAY AND
TONIGHT...BECOMING WEST-SOUTHWEST ON SUNDAY BEHIND THE BOUNDARY.

SPECIFICS FOR KSTL...PREVAILING CONDITIONS SHOULD BE VFR WITH
MAINLY MID-HIGH LEVEL CLOUDS AND SCATTERED DIURNAL CUMULUS CLOUDS.
SOUTHWEST SURFACE WINDS OF 10KT WILL VEER AROUND TO A WEST-SOUTHWEST
DIRECTION SUNDAY AS A WEAKENING FRONT/SFC TROUGH MOVES ACROSS THE
TERMINAL. THUNDERSTORM CHANCES ARE COMPLICATED...BUT FEEL THAT THE
PROB30 FOR LATE TONIGHT/EARLY SUNDAY MORNING IS WARRENTED GIVEN
AVAILABLE MODEL GUIDANCE.

CVKING

&&

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

$$

WFO LSX