AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAKE CHARLES LA
1143 PM CDT TUE JUN 18 2013
.AVIATION...RAIN CHANCES DIMINISH DURING THE OVERNIGHT HOURS AS AN
UPPER LEVEL TROF AXIS MOVES THROUGH. NORTHWESTERLY FLOW ALOFT WILL
HELP WASH OUT AN OLD FRONTAL BOUNDARY. WHILE I WOULD NOT RULE OUT
A FEW SHOWERS DEVELOPING WEDNESDAY AFTERNOON, A BETTER CHANCE WOULD
BE WEDNESDAY EVENING AS ANOTHER SHORT WAVE MOVES INTO OUR WESTERN
TERMINALS SO WILL MENTION VCSH FOR ALL BUT THE ACADIANA TERMINALS
AT THAT TIME. CONTINUED VFR.
SWEENEY
&&
.PREV DISCUSSION... /ISSUED 1000 PM CDT TUE JUN 18 2013/
DISCUSSION...
LOCAL 88DS SHOW CONVECTION ASSOCIATED WITH ADVANCING SHORTWAVE
ENERGY ALOFT AND AN OUTFLOW FROM EARLIER STORMS IS STEADILY
DISSIPATING AS IT PUSHES EWD ACROSS THE AREA. AIRMASS ACROSS THE
FORECAST AREA SHOULD BE FAIRLY WELL WORKED OVER THANKS TO THIS
LATEST ROUND OF CONVECTION BUT WITH A JUICY AIRMASS LINGERING AND
THE SHORTWAVE SLOWLY CROSSING THE AREA OVERNIGHT...ONLY LOWERED
POPS A LITTLE FROM PREVIOUS FORECAST...PRIMARILY OVER THE WRN 1/2
OF THE AREA. OTHERWISE JUST MINOR TWEAKS TO INHERITED
GRIDS/FORECASTS BASED ON LATEST TRENDS.
UPDATE OUT SHORTLY.
25
PREV DISCUSSION... /ISSUED 642 PM CDT TUE JUN 18 2013/
AVIATION...A BAND OF SHOWERS AND THUNDERSTORMS MOVING OUT AHEAD
OF A STATIONARY FRONTAL BOUNDARY IS PUTTING OUT AN OUTFLOW
BOUNDARY THAT LOOKS TO BE AN HOUR OUT OF LCH. SINCE THIS BOUNDARY
IS MOVING SOUTHEAST AT 20 KNOTS, WILL INCLUDE A TEMPO FOR NW WINDS
GUSTING 20 TO 30 KNOTS WITH POSSIBLE TSTMS PRODUCING MVFR VIS AT
LCH FOR THE NEXT FEW HOURS. MVFR VIS IN WEAKENING TSTMS AROUND AEX
BUT POSSIBLE STRONGER STORMS AN HOUR OUT MOVING IN FROM THE SW
WITH IFR VIS. BPT COULD SEE WEAK MVFR TSTMS OVER THE NEXT COUPLE
OF HOURS AS THE BAND HANGS UP JUST TO THE NORTH WITH POSSIBLE NEW
DEVELOPMENT NEAR THE OUTFLOW BOUNDARY. THE ACADIANA AIRPORTS LOOK
TO BE SUITABLE ALTERNATES WITH VFR CONDITIONS.
SWEENEY
PREV DISCUSSION... /ISSUED 243 PM CDT TUE JUN 18 2013/
SYNOPSIS...
A STATIONARY FRONT EXTENDS THROUGH GREENWOOD MS THROUGH TYLER THIS
EVENING...WILL OSCILLATE NORTH AND SOUTH OVER THE NEXT FEW DAYS.
THE BERMUDA HIGH PRESSURE SYSTEM RIDGES WESTWARD THROUGH SOUTH
FLORIDA AND INTO THE GULF OF MEXICO.
FURTHER UP...A DOME OF HIGH PRESSURE ACROSS OLD MEXICO WILL DRIFT
NORTHEAST OVER THE NEXT FEW DAYS. THIS SEMI-PERMANENT ANTICYCLONE
WILL TAKE ON A POSITIVE TILT ON SATURDAY...WITH RIDGE AXIS EXTENDING
THROUGH WEST TEXAS TO ILLINOIS.
DISCUSSION...
A LIFTING MECHANISM IS SETTING UP ACROSS THE WESTERN UPPER GULF
COAST STATES. THE OUTER WESTERN PERIPHERY OF THE BERMUDA HIGH
PRESSURE SYSTEM IS STEERING CARIBBEAN AIR THROUGH THE NORTHWEST GULF
OF MEXICO. THE TRAVELING CARIBBEAN AIR ASCENDS UPON APPROACHING THE
STATIONARY FRONT (TROUGH OF LOWER PRESSURE).
FURTHER UP...THE GFS MODEL DEPICTS A VIGOROUS WESTERLY SHORTWAVE
TRAVELING INTO WESTERN LOUISIANA THIS EVENING...BEFORE EXITING INTO
MISSISSIPPI BY WEDNESDAY EVENING.
THE INGREDIENTS FOR SHOWERS AND THUNDERSTORMS WILL IS IN PLACE TONIGHT.
THE COMBINED LIFT WILL BE ADEQUATE. THE LIFT ATTENDING THE UPSLIDING
CARIBBEAN AIR WILL GET AN ADDITIONAL BOOST FROM THE TRAVELING
WESTERLY SHORTWAVE.
MOISTURE WILL BE ADEQUATE AS WELL WITH PRECIPITABLE WATER RUNNING
SLIGHTLY ABOVE 2 INCHES (ABOUT 2 STANDARD DEVIATIONS ABOVE THE
MID-JUNE BENCHMARK NORMALS).
INSTABILITY WILL BE ADEQUATE. THE K-INDEX WILL BE RUNNING IN THE MID TO
UPPER 30'S (CELSIUS DEGREES). THE POTENTIAL CONVECTIVE INSTABILITY
BE RUNNING AROUND 3000 J PER KG THIS EVENING.
ISOLATED SEVERE WEATHER IS POSSIBLE (MICROBURSTS). HOWEVER...THE PRIMARY
THREAT WILL BE LOCALIZED FLOODING RAIN.
21
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 74 89 75 91 75 / 60 50 10 30 10
KBPT 75 90 75 91 75 / 60 50 10 20 10
KAEX 71 88 71 91 72 / 60 50 10 30 10
KLFT 74 89 75 91 75 / 60 50 30 30 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...NONE.
&&
$$
