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000
FXUS63 KLSX 180755
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
255 AM CDT TUE JUN 18 2013

.SHORT TERM...(THROUGH LATE THIS AFTERNOON)
ISSUED AT 255 AM CDT TUE JUN 18 2013

EARLY THIS MORNING...UPPER LEVEL RIDGE EXISTS OVER THE ERN ROCKIES
WITH A TROF OVER THE ERN CONUS...GIVING OUR AREA NW FLOW.  A
DECENTLY STRONG SHORTWAVE TROF IS DROPPING SE THRU ERN SD AND SWRN
MN AND KICKING OFF TSRA...WHILE SHORTWAVE THAT DUMPED A BUNCH OF
RAIN OVER PARTS OF OUR AREA ON MONDAY HAS SINCE EXITED AND IS OVER
THE LOWER OH VALLEY.  AT THE SFC...CALM WINDS ABOUND WITH VERY WEAK
PRES GRADIENT ACROSS OUR REGION TYPICAL OF SUMMERTIME.  A WEAK
BACKDOOR CDFNT FROM ERN IA THRU NRN IL TO CNTRL INDIANA IS MOVING
VERY SLOWLY SWWD.  PATCHY DENSE FOG HAS FORMED IN AREAS THAT HAVE
CLEARED OUT AND RECEIVED RAINFALL ON MONDAY.  TEMPS HAVE SLIPPED
INTO THE 60S.

A 25 VORT MAX ASSOCIATED WITH THE SHORTWAVE OVER SWRN MN IS EXPECTED
TO CONTINUE TO DROP SEWD AND TRACK THRU THE QUAD CITIES AREA EARLY
THIS AFTERNOON AND THEN INTO E-CNTRL IL BY EARLY EVENING...AND WILL
VERY CLOSELY MIRROR THE BACKDOOR SFC CDFNT AS IT DROPS INTO THAT
SAME REGION THIS AFTERNOON AND EFFECTIVELY EDGE OUR NERN FA AND
PROVIDES A FOCUS FOR TSRA DEVELOPMENT.  THE AIR IT WILL BE
INTERSECTING WILL BE VERY WEAKLY CAPPED...SUFFICIENTLY MOIST WITH
PWATS AROUND 1.25 INCHES...AND ADEQUATELY UNSTABLE WITH SBCAPES IN
THE 1000-2000 J/KG RANGE.  DEEP LAYER SHEAR OF 35-40KTS WILL PROMOTE
ORGANIZED DEVELOPMENT WITH A RELATIVELY BRIEF WINDOW IN THE MID-LATE
AFTN FOR STRONG-SEVERE POTENTIAL FOR WIND AND HAIL.  HAVE EDGED POPS
INTO CHANCE CATEGORY TOWARDS CNTRL IL AND KEPT MENTIONABLE POPS TO
THE NE EDGES OF THE STL METRO AREA AND MS RIVER...WITH THE BULK OF
THE TSRA ACTIVITY EXPECTED TO BE JUST TO THE NE.

H850 TEMPS BETWEEN 14-16C SHOULD GIVE US MAX TEMPS IN THE BALLPARK
THAT MOS IS GIVING US FOR MOST SITES...ALTHOUGH MOS LOOKS A BIT TOO
COOL AT KUIN AND ADJUSTED UP A COUPLE DEGS.

TES

.LONG TERM...(TUESDAY THROUGH NEXT MONDAY)
ISSUED AT 238 PM CDT MON JUN 17 2013

TUESDAY AND WEDNESDAY...

REINFORCING COLD FRONT FROM THE GREAT LAKES...IN CONJUNCTION WITH A
SHORTWAVE DIVING SOUTHEAST FROM THE UPPER MIDWEST TOWARD THE OHIO
RIVER VALLEY WILL PROBABLY INITIATE SOME CONVECTION TUESDAY
AFTERNOON ACROSS ILLINOIS. BEST CHANCES MAY REMAIN EAST OF THE
CWA...BUT CANT RULE OUT SOME ISOLATED STORMS...SO HAVE MAINTAINED
LOW CHANCE POPS. UPSTREAM OBSERVATIONS IN IOWA THIS AFTERNOON
SUGGEST HIGHS IN THE MIDDLE 80S FOR TUESDAY.

DRY WEATHER AND SLIGHTLY COOLER TEMPERATURES EXPECTED TUESDAY NIGHT
THROUGH WEDNESDAY NIGHT AS SURFACE RIDGE OF HIGH PRESSURE MOVES
SOUTHEAST ACROSS THE REGION.

THURSDAY...

UPPER LEVEL RIDGE BUILDS ACROSS THE PLAINS WEDNESDAY NIGHT AND
THURSDAY....BUT A SHORTWAVE IS PROGGED BY MODEL GUIDANCE TO RIDE UP
AND OVER THE RIDGE TOWARD THE CWA. AT THE SAME TIME...A SURFACE WARM
FRONT SHOULD BE ADVANCING NORTHEAST. HAVE MAINTAINED CHANCE POPS AS
MCS COULD MOVE INTO THE CWA THURSDAY MORNING...AND/OR ADDITIONAL
STORMS COULD FIRE THURSDAY AFTERNOON. TEMPERATURES WILL BE DEPENDENT
ON PRECIPITATION AND CLOUD COVER...BUT POTENTIAL CERTAINLY THERE FOR
HIGHS TO BOUNCE BACK TO NORMAL ON THURSDAY.

FRIDAY THROUGH MONDAY...

TEMPERATURES TO WARM ABOVE NORMAL DURING THE PERIOD AS THE UPPER
LEVEL RIDGE BUILDS ACROSS THE CWA. HAVE MAINTAINED THE DRY EXTENDED
FORECAST AS THIS PATTERN WOULD SUGGEST ONLY SLIGHT CHANCES OF
THUNDERSTORMS MOVING INTO THE NORTHERN CWA.

CVKING

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 1135 PM CDT MON JUN 17 2013

RAIN HAS ENDED...AND VFR CLOUD COVER WILL CONTINUE TO THIN
OVERNIGHT. GIVEN HEAVY RAINFALL EARLIER MONDAY AT
KSUS...KSTL...AND KCPS...AND CALM WINDS...SOME FOG MIGHT FORM
AFTER THE CLOUDS CLEAR. GENERALLY WENT WITH MVFR VSBYS...WITH IFR
AT KSUS AND KCPS. OTHERWISE VFR CONDITIONS EXPECTED ON TUESDAY AS
ANOTHER DISTURBANCE TRACKS WELL TO THE NORTHEAST OF ALL TAF SITES.
NORTH WINDS WILL INCREASE TOMORROW AS SURFACE HIGH PRESSURE BEGINS
TO BUILD INTO THE AREA.

SPECIFICS FOR KSTL...VFR CONDITIONS EXPECTED THROUGH THIS TAF
PERIOD. SOME LIGHT FOG IS POSSIBLE BEFORE SUNRISE DUE TO CALM
WINDS...CLEARING SKIES AND HEAVY RAINS EARLIER ON MONDAY. NORTH
WINDS WILL INCREASE A BIT ON TUESDAY AS HIGH PRESSURE STARTS TO
BUILD IN.

BROWNING

&&

.PRELIMINARY POINT TEMPS/POPS...
SAINT LOUIS     86  62  84  65 /  10  20   5  10
QUINCY          82  58  81  64 /  20  10  10  20
COLUMBIA        85  62  84  66 /   5  10  10  20
JEFFERSON CITY  85  62  85  66 /   5  10  10  20
SALEM           85  61  82  64 /  20  30   5   5
FARMINGTON      86  61  83  62 /   5  10  10  10

&&

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

$$

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