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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBUF 171142
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
742 AM EDT MON JUN 17 2013

.SYNOPSIS...
A WAVE OF LOW PRESSURE ASSOCIATED WITH AN UPPER LEVEL TROUGH WILL
BRING A WEAK COLD FRONT ACROSS THE REGION TODAY. THIS FRONT WILL
KICK OFF SHOWERS AND THUNDERSTORMS FROM THIS AFTERNOON INTO TONIGHT
AS IT SAGS SOUTH. ON TUESDAY A LARGE AREA OF HIGH PRESSURE WILL THEN
MOVE INTO THE GREAT LAKES AND REMAIN NEARLY STATIONARY OVER THE
REGION THROUGH THE REST OF THE WEEK. THIS PATTERN WILL GENERATE SOME
AND SEASONAL TEMPERATURES.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
BROAD UPPER LEVEL TROUGHINESS IS FOUND ACROSS EASTERN CANADA
SOUTHWARD TO THE GREAT LAKES AND NORTHEAST REGION THIS MORNING.
SURFACE ANALYSIS SHOWS LOW PRESSURE CENTERED OVER SOUTH CENTRAL
QUEBEC WITH A SLOW MOVING COLD FRONT ORIENTED FROM THIS LOW WESTWARD
JUST NORTH OF THE LOWER AND CENTRAL GREAT LAKES. AREA RADARS ARE
SHOWING SOME SCATTERED SHOWERS NORTH OF LAKE ONTARIO  WHICH HAVE
BEEN TRIGGERED BY THE FRONT. THROUGH TODAY AND TONIGHT MODELS SHOW
THIS FRONT WILL SLOWLY CONTINUE TO PRESS SOUTHWARD TOWARD LAKE
ONTARIO AND NEW YORK STATE. FORCING AHEAD OF AND ALONG THE FRONT
COUPLED WITH DECENT MOISTURE /DEWPOINTS IN THE UPPER 50S TO LOW 60S/
AND INCREASING INSTABILITY GOING INTO THE AFTERNOON WILL KICK OFF
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS FURTHER SOUTH ACROSS
THE LAKE THEN INTO WESTERN AND CENTRAL NEW YORK. ALL SHORT TERM
GUIDANCE SHOWS THIS SCENARIO SO HAVE INCLUDED HIGH CHANCES FOR
CONVECTION MAINLY FROM LATE AFTERNOON INTO THIS EVENING.

MOSTLY SUNNY SKIES THIS MORNING ACROSS THE FORECAST AREA BUT MORE
BROKEN CLOUD COVER IS FOUND TO THE NORTH NEAR THE FRONTAL ZONE. MUCH
OF THIS MORNING WILL ALLOW FOR GOOD SURFACE HEATING WITH HIGH TEMPERATURES
REACHING THE MID TO UPPER 70S TO AROUND 80. NAM AND GFS SURFACE
CAPES ARE FORECAST TO REACH BETWEEN 1000 AND 1500 J/KG BY MID
AFTERNOON WHICH WOULD SUPPORT SOME STRONGER CORES WITHIN STORMS THAT
DEVELOP. HAIL AND GUSTY WINDS WILL BE THE MAIN THREAT.
UNIDIRECTIONAL FLOW ALOFT FROM MODEL BUFKIT PROFILES SHOULD PREVENT
ANY STORMS FROM ROTATING BUT MAY ALLOW FOR LINER CELL SEGMENTS TO
FORM. ADDITIONAL FORCING MAY BE FOUND AGAIN LATER OVERNIGHT AS A
SHORTWAVE IN THE UPPER FLOW MAY HELP FORM A SURFACE WAVE ALONG THE
FRONT. WITH THE FRONT NOT PUSHING THROUGH TILL TUESDAY EXPECT
ANOTHER NIGHT OF MILD TEMPS.
-- End Changed Discussion --

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
A COOL FRONT WILL CONTINUE TO SAG SOUTH ACROSS THE FORECAST AREA
DURING THE DAY ON TUESDAY. MODEL GUIDANCE HAS CONTINUED THE TREND OF
SLOWING THE PROGRESSION OF THE FRONT FROM RUN TO RUN AND THEREFORE
WILL KEEP A CHANCE OF SHOWERS IN ACROSS THE AREA A FEW HOURS LONGER
THAN THE PREVIOUS FORECAST. OTHERWISE LOOK FOR SHOWERS TO END FROM
NORTH TO SOUTH DURING THE DAY ON THURSDAY AS COOLER AND DRIER AIR
ADVECTS INTO THE REGION FROM CANADA. TUESDAY/S HIGHS WILL REFLECT
THIS COOLER AIRMASS WITH HIGHS TOPPING OUT IN THE UPPER 60S TO
AROUND 70.

HIGH PRESSURE BUILDING ACROSS THE LOWER GREAT LAKES IN THE WAKE OF
THE COOL FRONT WILL DOMINATE WESTERN AND NROTH CENTRAL NEW YORK
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. EXPECT FAIR SKIES AND
TEMPERATURES THAT WILL RUN SLIGHTLY BELOW NORMAL WITH HIGHS AROUND
70 ON WEDNESDAY WITH LOWS RANGING FROM THE MID 40S TO THE LOWER 50S
TUESDAY AND WEDNESDAY NIGHTS.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
DURING THE FIRST COUPLE DAYS OF THE EXTENDED PERIOD...LINGERING
BROAD/RELATIVELY FLAT TROUGHING ALOFT WILL GIVE WAY TO A MORE ZONAL
FLOW ACROSS OUR REGION...WHILE SURFACE HIGH PRESSURE SLOWLY DRIFTS
FROM THE SPINE OF THE APPALACHIANS TO A POSITION OFF THE EAST COAST
BY FRIDAY. THIS WILL RESULT IN CONTINUED MAINLY DRY WEATHER THROUGH
THE END OF THE WORK WEEK...THOUGH A COUPLE WEAK FEATURES DROPPING
THROUGH THE BACKSIDE OF THE DEPARTING TROUGH COULD TOUCH OFF AN
ISOLATED SHOWER OR TWO ACROSS THE SAINT LAWRENCE VALLEY/NORTH
COUNTRY BOTH THURSDAY AND FRIDAY.

AS WE GET INTO NEXT WEEKEND...INCREASING RETURN FLOW ON THE BACKSIDE
OF THE RIDGE SHOULD PUMP SOMEWHAT MORE HUMID AIR BACK INTO OUR
REGION...AND THIS COUPLED WITH DAYTIME HEATING AND THE APPROACH OF
THE NEXT FRONTAL SYSTEM SHOULD EVENTUALLY RESULT IN A MORE GENERAL
CHANCE OF SOME SCATTERED CONVECTION BY SATURDAY NIGHT AND SUNDAY.
ACCORDINGLY...HAVE INDICATED POPS CLIMBING BACK TO LOW CHANCE LEVELS
DURING THIS TIME FRAME.

WITH RESPECT TO TEMPERATURES...THE ABOVE EVOLUTION IN THE PATTERN
WILL ALSO RESULT IN READINGS MODERATING BACK TO NEAR NORMAL LEVELS
BY THURSDAY...THEN TO AT LEAST A BIT ABOVE NORMAL FOR THE REMAINDER
OF THE PERIOD. MORE SPECIFICALLY...DAYTIME HIGHS IN THE 70S ON
THURSDAY SHOULD WARM BACK TO AT LEAST THE LOWER 80S FOR THE
WEEKEND...WITH SOME READINGS IN THE MID 80S POSSIBLE DEPENDING ON
BOTH THE EVENTUAL TEMPERATURES ALOFT AND THE AREAL COVERAGE OF ANY
CONVECTION/ASSOCIATED CLOUD COVER. AS MENTIONED ABOVE...HUMIDITY
LEVELS SHOULD ALSO BE ON THE RISE...WITH COMFORTABLE DEWPOINTS OF
AROUND 50 ON THURSDAY CLIMBING BACK TO MODERATELY HUMID LEVELS IN
THE LOWER 60S BY SUNDAY.

&&

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
-- Changed Discussion --
THERE WAS SOME MVFR LEVEL FOG/BR FOUND AT SOME OF THE TAF SITES THIS
MORNING BUT HAS MAINLY YIELDED TO VFR NOW UNDER MAINLY SUNNY SKIES.
VFR WILL REMAIN THE DOMINATE FIGHT CONDITION FOR THE MAJORITY OF
TODAY. THE MAIN FOCUS WILL BE ON SHOWERS AND THUNDERSTORMS WHICH ARE
EXPECTED TO DEVELOP THIS AFTERNOON AND EVENING AHEAD OF A COLD FRONT
DROPPING SOUTH FROM CANADA...SHOWERS MAY MOVE INTO KART BY MID
MORNING. VCTS AND CB REMAIN IN THE TAF AT THIS TIME. THERE STILL
REMAINS SOME UNCERTAINTY TO BE CONFIDENT ABOUT THE TIMING OF TSRA
GROUPS IN THE TAF SO WILL CONTINUE WITH VCTS FOR NOW.

OUTLOOK...
MONDAY NIGHT AND TUESDAY...MAINLY VFR WITH A CHANCE OF SHOWERS AND
THUNDERSTORMS.
WEDNESDAY THROUGH FRIDAY...VFR.
-- End Changed Discussion --

&&

.MARINE...
UNSETTLED CONDITIONS EXPECTED TO DEVELOP THIS AFTERNOON THROUGH
TONIGHT AS SHOWERS AND THUNDERSTORMS DEVELOP AHEAD OF A COLD FRONT
EXPECTED TO DROP SOUTH FROM CANADA OVER THE NEXT 24 HOURS. BY
WEDNESDAY HIGH PRESSURE WILL BUILD BACK ACROSS THE LOWER LAKES WITH
TRANQUIL CONDITIONS.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...SMITH
NEAR TERM...SMITH
SHORT TERM...WOOD
LONG TERM...JJR
AVIATION...SMITH
MARINE...SMITH