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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KPBZ 270501 AAD
AFDPBZ

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PITTSBURGH PA
101 AM EDT SUN JUL 27 2014

.SYNOPSIS...
SHOWER AND THUNDERSTORM CHANCES...WITH THE RISK OF SEVERE WEATHER...WILL
INCREASE TODAY. COLDER WEATHER CAN BE EXPECTED FOR NEXT WEEK.

&&

.NEAR TERM /THROUGH TODAY/...
FOCUSED ON TWO SHORTWAVE FOR THE OVERNIGHT PERIOD. ONE OVER MY
AREA AND ONE TO THE WEST. SHORTWAVE OVER MY AREA WILL QUICKLY MOVE
SOUTHEASTWARD AND BY EARLY SUNDAY MORNING BE NEAR THE EAST COAST.
WESTERN WAVE WILL MOVE FROM SOUTHERN INDIANA TO SOUTHERN WEST
VIRGINIA OVERNIGHT. I AM A LITTLE SUSPECT ABOUT THE TRACK OF THE
WESTERN WAVE. CONVECTION CURRENTLY OVER THE AREA IS DIVING MORE
SOUTH THEN EAST. I WOULD THINK THAT THIS WILL DRIVE WESTERN WAVE A
BIT FURTHER SOUTH. THIS WOULD ALLOW FOR ACTIVITY TO DIE DOWN
OVERNIGHT HERE AND LESSEN THE THREAT FOR ADDITIONAL ACTIVITY TO
DEVELOP TOWARD DAWN FROM WESTERN WAVE.

LATEST MODEL DATA IS NOT AS IMPRESSIVE WITH THE SEVERE THREAT
TODAY AS PREVIOUS RUNS. A TRIGGER TO GET THINGS ROLLING IS LACKING
AS OVERNIGHT SHORTWAVES HAVE ROBBED THE ATMOSPHERE OF ENERGY. IT
NOW APPEARS THAT THE NEXT MAIN WAVE WILL NOT ARRIVE UNTIL LATE IN
THE DAY...JUST AHEAD OF THE MAIN TROUGH AND SURFACE BOUNDARY.
ATMOSPHERE NOT QUITE AS BUOYANT AS PORTRAYED IN PREVIOUS RUNS AND
SHEAR VALUES HAVE ALSO DECREASED. THE OTHER CONCERN WILL BE
SUNLIGHT...OR THE LACK THERE OFF. MODELS ARE SHOWING A LOT OF
RESIDUAL MOISTURE IN THE LOWER AND MID-LEVELS LINGERING OVER THE
REGION TODAY. WITH WHAT MODELS ARE DETAILING...IF SEVERE WEATHER
ERUPTS IT LIKELY WILL NOT BE UNTIL LATER IN THE DAY.

THIS IS A COMPLEX AND CONSTANTLY CHANGING SITUATION...DEPENDENT ON
MANY FACTORS.

&&

.SHORT TERM /TONIGHT THROUGH TUESDAY/...
SURFACE SYSTEM WILL QUICKLY EXIT TO THE EAST OVERNIGHT. UPPER
LEVEL SYSTEM WILL SWING IN BEHIND IT. STORM CHANCES WILL DIMINISH
OVERNIGHT...BUT SHOWERS WILL CONTINUE AS UPPER LEVEL SYSTEM MOVES
THROUGH.

MOISTURE WILL CONTINUE TO WRAP AROUND THE EXITING TROUGH ON
MONDAY...KEEPING IN THE RISK FOR SHOWERS. ATMOSPHERE IS NOT
SHOWING A GREAT DEAL OF INSTABILITY MONDAY AND WITH LOTS OF CLOUD
COVER...STORM THREAT SHOULD BE GREATLY REDUCED.

SHOWERS WILL END MONDAY NIGHT...AND MUCH COOLER AIR WILL DIVE
SOUTHWARD OVER THE UPPER OHIO VALLEY.

TUESDAY SHOULD SEE AN INCREASE IN SUNSHINE...BUT WITH BELOW NORMAL
TEMPS.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
HIGH PRESSURE UNDER UPPER LEVEL TROUGH WILL PROVIDE A COOL AND
COMFORTABLE MIDWEEK. ANOTHER WEAK COLD FRONT MAY BRING SHOWERS
THURSDAY. HIGH PRESSURE WILL RETURN FRIDAY. WARMER AIR AND THE
RISK FOR SHOWERS FOR THE BEGINNING OF THE WEEKEND.

&&

.AVIATION /05Z SUNDAY THROUGH THURSDAY/...
SEVERAL SHORTWAVES WILL CONTINUE THE CHANCE FOR SHOWERS AND
THUNDERSTORMS AND OCCASIONAL RESTRICTIONS THROUGH MUCH OF THE
TAF PERIOD. WENT WITH A GENERAL VCSH MENTION AND TRIED TO TEMPO
SHOWERS/STORMS AS NEEDED OVERNIGHT AS STORMS MOVING SOUTH FROM
LAKE ERIE AND THE MCS OVER IN/IL APPROACH. LOOKING AT DOWNSTREAM
OBS OVER WESTERN OHIO...MANY TAF SITES MAY EXPERIENCE MVFR CIGS
FOR A PERIOD OVERNIGHT. OPTED TO MENTION THIS ACROSS THE BOARD BUT
CONFIDENCE WAS NOT GREAT ENOUGH TO MAKE IT PREVAILING EVERYWHERE.

WHILE CONDITIONS MAY RETURN TO VFR EVERYWHERE TOMORROW
MORNING...ADDITIONAL STRONG TO SEVERE STORMS WILL BE POSSIBLE IN
THE AFTERNOON AS LOW PRESSURE APPROACHES. WILL MAINTAIN THE VCTS
MENTION FOR NOW CONSIDERING THE LOW CONFIDENCE IN EXACT TIMING BUT
EXPECT VSBY RESTRICTIONS WILL OCCUR AT ANY SITE THAT ENCOUNTERS A
T-STORM.

OUTLOOK.../SUNDAY NIGHT THROUGH THURSDAY/...
RSTRNS ARE LIKELY THRU MON AS A CDFNT CROSSES THE RGN.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$