000
FXUS62 KCAE 202359
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
759 PM EDT MON MAY 20 2013

.SYNOPSIS...
PERSISTENT UPPER LEVEL TROUGH WILL REMAIN OVER THE REGION THROUGH
TUESDAY CONTINUING THE CHANCE OF SHOWERS AND THUNDERSTORMS. A
STRONGER UPPER LEVEL TROUGH WILL CROSS THE CENTRAL US DURING THE
MIDDLE OF THE WEEK AND INTO THE EASTERN US ON FRIDAY RESULTING IN
ADDITIONAL CHANCES OF SHOWERS AND THUNDERSTORMS. DRIER WEATHER IS
EXPECTED BY NEXT WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
FOCUS FOR SHOWERS AND THUNDERSTORMS SHIFTING INTO THE LOW COUNTRY
ALONG AXIS OF STRONGER INSTABILITY/WEAK SURFACE TROUGH. DOWNWARD
VERTICAL MOTION ACROSS WESTERN MIDLANDS/CSRA AS UPPER TROUGH MOVES
FURTHER EAST...SO CUT POPS WAY BACK ACROSS THE WESTERN MIDLANDS/CSRA.
CHANCE EAST EARLY THIS EVENING.

FOG IS ALSO EXPECTED TO DEVELOP TOWARD DAYBREAK AS PLENTY OF
MOISTURE WILL BE TRAPPED UNDER THE DEVELOPING INVERSION AND WINDS
WILL BE LIGHT. WITH THE CLOUDS OVER THE AREA OVERNIGHT LOW
TEMPERATURES WILL GENERALLY BE IN THE MIDDLE 60S.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
THE CURRENT WEAK UPPER LEVEL TROUGH THAT HAS PERSISTED ACROSS THE
REGION IS EXPECTED TO REMAIN ACROSS THE SOUTHEAST INTO THURSDAY.
THEN A STRONGER/DEEPER TROUGH WILL PUSH IN FROM THE WEST THURSDAY
AND THURSDAY NIGHT. UNTIL THE MAIN TROUGH PASSES...EXPECT TYPICAL
AFTERNOON SHOWERS AND THUNDERSTORMS TO DEVELOP AND LAST INTO THE
EVENING HOURS BEFORE DISSIPATING. RAIN CHANCES WILL BE MOSTLY
DEPENDENT UPON THE STRENGTH AND MOVEMENT OF THE SEA-BREEZE...ALONG
WITH THE POSITION OF THE UPPER TROUGH. FOR NOW HAVE GENERALLY GOING
WITH CHANCE POPS ACROSS THE FORECAST AREA DURING THE
AFTERNOON/EVENING HOURS. AS FOR TEMPS...WITH A LITTLE MORE
SUNSHINE...EXPECTING HIGHS TO REACH THE MID 80S. OVERNIGHT LOWS IN
THE 60S.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
THE MAIN UPPER TROUGH WILL BE SWINGING EAST OF THE REGION BY
FRIDAY...WHILE AT THE SURFACE...DRIER HIGH PRESSURE WILL BEGIN
BUILDING BACK INTO THE REGION FROM THE NORTH. UPPER FLOW WILL BE
OUT OF THE NORTHWEST. SURFACE FLOW ALSO OUT OF THE NORTH.  THIS
LEADS TO A DRY WEATHER PATTERN AS WE MOVE THROUGH THE WEEKEND.
HIGHS STILL GENERALLY IN THE MID 80S. LOWS WILL BE SLIGHTLY COOLER
WITH READINGS IN THE UPPER 50S TO LOWER 60S.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
ATMOSPHERE IS A LITTLE DRIER TODAY THAN YESTERDAY AND AFTERNOON
CONVECTION HAS SHIFTED SOUTHEAST OF THE TERMINALS. SKIES WILL BE
PARTLY TO MOSTLY CLOUDY THIS EVENING AS CONVECTIVE DEBRIS CLOUDS
REMAIN OVER THE AREA BUT SHOULD THIN LATER TONIGHT. LOW LEVEL JET
IS NOT AS STRONG TONIGHT AND LOW LEVEL MOISTURE REMAINS PLENTIFUL
SO FOG FIGURES TO BE A MORE FAVORED THREAT. LIGHT TO CALM WINDS
OVERNIGHT WILL ALLOW SOME RADIATIONAL COOLING AND EXPECT SOME FOG
TO DEVELOP AFTER 07Z-09Z. WILL INCLUDE SOME IFR VSBYS AT AGS/OGB
AND POSSIBLE THEY COULD OCCUR AT CAE 09Z-12Z. CONFIDENCE IS A
LITTLE HIGHER TONIGHT THAN PREVIOUS NIGHTS BUT GUIDANCE HAS NOT
BEEN GREAT AS OF LATE. ANY FOG SHOULD BURN OFF BY 14Z WITH VFR
CONDITIONS EXPECTED FOR THE REMAINDER OF THE PERIOD. WINDS WILL
PICK UP OUT OF THE SOUTH TO SOUTHEAST AROUND 5-7 KNOTS.

EXTENDED AVIATION OUTLOOK...SCATTERED SHOWERS AND
THUNDERSTORMS...MAINLY AFTERNOON AND EVENING...POSSIBLE THROUGH
FRIDAY. LATE NIGHT/EARLY MORNING FOG/STRATUS ALSO POSSIBLE.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

$$