AP-LE--BUF-NY Lake Erie Area Forecast Discussion, LE

000

FXUS61 KBUF 151334

AFDBUF

AREA FORECAST DISCUSSION

NATIONAL WEATHER SERVICE BUFFALO NY

934 AM EDT WED JUL 15 2015

.SYNOPSIS...

HIGH PRESSURE WILL BUILD ACROSS THE REGION TODAY BRINGING

CLEARING SKIES TO THE AREA. THE HIGH WILL MOVE TO NORTHERN NEW

ENGLAND BY FRIDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...

NORTHERLY FLOW CAUSING UPSLOPE CLOUDINESS THIS MORNING ACROSS

MUCH OF THE REGION. CLOUDS WILL CLEAR FROM NORTH TO SOUTH LATER

THIS MORNING. CLOUDS MAY LINGER INTO THE AFTERNOON ACROSS THE

SOUTHERN TIER AND FINGER LAKES REGIONS AS UPSLOPE FLOW MAINTAINS

WEAK LIFT. CLOUDS WILL THIN ALL AREAS THROUGH THE AFTERNOON AS A

STRONG PUSH OF DRIER AIR MOVES SOUTH OUT OF ONTARIO AND QUEBEC.

LOW LEVEL COLD ADVECTION WILL BRING A COOLER AND MUCH LESS HUMID

AIRMASS INTO THE REGION.

HIGH PRESSURE WILL OVERSPREAD THE REGION TONIGHT WITH LOWER

DEWPOINTS. OVERNIGHT LOW TEMPERATURES WILL BE IN THE LOWER TO MIDDLE

50S...EVEN UPPER 40S ACROSS THE SOUTHERN TIER. EXPECT VALLEY FOG TO

FORM ACROSS THE SOUTHERN TIER AS WELL.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...

HIGH PRESSURE OVERHEAD ON THURSDAY WILL PROVIDE NEARLY FULL SUNSHINE

WITH JUST A FEW DIURNAL CUMULUS DURING THE AFTERNOON INLAND FROM THE

LAKES. A RELATIVELY COOL AIRMASS WILL STILL BE IN PLACE BY MID

SUMMER STANDARDS. EXPECT HIGHS IN THE MID 70S ACROSS LOWER

ELEVATIONS AND LOWER 70S ON THE HILLS. NORTHEAST WINDS WILL KEEP THE

SOUTH SHORE OF LAKE ONTARIO COOLER AS WELL.

HIGH PRESSURE WILL DRIFT EAST ACROSS NEW ENGLAND THURSDAY NIGHT.

EXPECT GOOD RADIATIONAL COOLING CONDITIONS FOR THE FIRST HALF OF THE

NIGHT WITH CLEAR SKIES AND LIGHT WINDS IN THE COOL/DRY AIRMASS. THIS

WILL ALLOW LOWS TO DROP INTO THE UPPER 50S ON THE LAKE PLAINS WITH

SOME LOWER 50S IN THE COOLER SOUTHERN TIER VALLEYS AND EAST OF LAKE

ONTARIO. AFTER MIDNIGHT INCREASING WARM ADVECTION IN THE UPPER

LEVELS AHEAD OF THE NEXT SYSTEM WILL BRING AN INCREASE IN MID/HIGH

CLOUDS FROM WEST TO EAST.

ON FRIDAY A SURFACE LOW WILL MOVE ACROSS THE CENTRAL GREAT LAKES...

WITH A DOWNSTREAM WARM FRONT MOVING EAST ACROSS OUR REGION. MODEL

GUIDANCE HAS TRENDED A LITTLE FASTER WITH THIS SYSTEM OVER THE PAST

24 HOURS...WITH THE ECMWF STILL THE MOST AGGRESSIVE IN BRINGING RAIN

CHANCES INTO THE AREA ON FRIDAY. FORCING WILL BE WEAK WITH A LOW

AMPLITUDE MID LEVEL SHORTWAVE AND BROAD WARM ADVECTION PROVIDING

MODEST LARGE SCALE ASCENT. MOISTURE WILL RAPIDLY RETURN ON FRIDAY

WITH DAYTIME HEATING ALLOWING SOME WEAK INSTABILITY TO DEVELOP. THIS

MAY ALLOW A FEW SCATTERED SHOWERS AND ISOLATED STORMS DURING THE

AFTERNOON AND EVENING...ESPECIALLY ALONG LAKE BREEZE BOUNDARIES

WHICH WILL PROVIDE AN ADDED BOOST OF FORCING. TEMPERATURES WILL

REBOUND WITH HIGHS IN THE LOW TO MID 80S ACROSS LOWER ELEVATIONS AND

AROUND 80 ON THE HILLS AND EAST OF LAKE ONTARIO.

FRIDAY NIGHT THE SURFACE LOW IS FORECAST TO MOVE ACROSS SOUTHERN

ONTARIO JUST NORTH OF LAKE ONTARIO WITH A MID LEVEL TROUGH TAKING A

SIMILAR TRACK. THE DPVA REGIME AHEAD OF THE MID LEVEL TROUGH AND

CONVERGENCE JUST SOUTH OF THE SURFACE LOW TRACK WILL PROVIDE A

LITTLE BETTER LARGE SCALE ASCENT...WITH ENOUGH INSTABILITY LINGERING

THROUGH THE NIGHT TO SUPPORT SCATTERED SHOWERS AND STORMS.

TEMPERATURES WILL STAY VERY MILD WITH LOWS IN THE UPPER 60S TO LOWER

70S ON THE LAKE PLAINS ALONG WITH HIGHER HUMIDITY.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...

THE LONG TERM WILL BECOME FAIRLY ACTIVE WITH A CHANCE OF SHOWERS AND

STORMS JUST ABOUT EVERY DAY...ALTHOUGH THERE WILL BE PLENTY OF RAIN

FREE TIME AS WELL. MOST OF THE CONVECTION WILL BE TIED TO THE

DIURNAL CYCLE AND ALSO SUBTLE SHORTWAVES MOVING ALONG THE

US/CANADIAN BORDER.

ON SATURDAY THE FIRST OF THESE WAVES WILL BE EXITING OFF THE NEW

ENGLAND COAST. LINGERING MOISTURE AND INSTABILITY MAY STILL PRODUCE

A FEW WIDELY SCATTERED SHOWERS AND STORMS ACROSS THE LOWER LAKES.

THIS SHOULD END SATURDAY NIGHT WITH THE LOSS OF DAYTIME HEATING AND

A BRIEF PERIOD OF SOMEWHAT DRIER MID LEVEL AIR. ON SUNDAY LATEST 00Z

GFS AND ECMWF RUNS SHOW LITTLE IN THE WAY OF SYNOPTIC SCALE

FORCING...ALTHOUGH DIURNAL INSTABILITY AND ANY LOCAL BOUNDARIES MAY

STILL ALLOW A FEW ISOLATED STORMS TO DEVELOP.

MONDAY AND MONDAY NIGHT BOTH THE GFS AND ECMWF BRING A MORE NOTABLE

MID LEVEL TROUGH THROUGH THE GREAT LAKES REGION. THIS SHOULD PROVIDE

ENOUGH FORCING TO BRING MORE ORGANIZED SHOWERS AND STORMS. SOME OF

THESE MAY LINGER INTO TUESDAY AS THE SYSTEM MOVES SLOWLY EAST

TOWARDS NEW ENGLAND.

TEMPERATURES WILL BECOME VERY WARM OVER THE WEEKEND AND EARLY NEXT

WEEK. EXPECT HIGHS TO REACH AT LEAST THE MID 80S AT LOWER ELEVATIONS

INLAND FROM THE LAKES...WITH UPPER 80S TO AROUND 90 POSSIBLE BY

SUNDAY AND MONDAY AS 850MB TEMPS CREEP UPWARD TOWARDS +20C. IT WILL

ALSO BECOME VERY HUMID WITH SURFACE DEWPOINTS APPROACHING 70F

SATURDAY THROUGH MONDAY.

&&

.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...

NORTHERLY FLOW CAUSING UPSLOPE CLOUDINESS THIS MORNING ACROSS

MUCH OF THE REGION. MVFR CEILINGS WILL PREVAIL AT MOST LOCATIONS

ALTHOUGH IFR TO LIFR CONDITIONS WILL BE FOUND ACROSS THE HIGHER

TERRAIN OF THE SOUTHERN TIER.

DRIER AIR WILL ADVECT ACROSS THE REGION WITH A SHARP CLEARING LINE

FROM NORTH TO SOUTH. BY LATE MORNING TO EARLY AFTERNOON THERE SHOULD

BE AN IMPROVEMENT BACK TO VFR CIGS...WITH CLEARING FOR ALL SITES.

OUTLOOK...

THURSDAY THROUGH SUNDAY...VFR THROUGH THE PERIOD. CHANCE

FOR SHOWERS AND THUNDERSTORMS WITH BRIEF FLIGHT REDUCTIONS FRIDAY

NIGHT THROUGH SATURDAY.

&&

.MARINE...

NORTHERLY WINDS WILL BOOST WAVE HEIGHTS TO SMALL CRAFT ADVISORY

LEVELS TODAY BEFORE DIMINISHING LATER TONIGHT. THURSDAY AND FRIDAY

WILL BE TRANQUIL UNDER HIGH PRESSURE.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...

NY...NONE.

MARINE...SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR LEZ040-

041.

SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON

FOR LOZ030-042>045.

&&

$$

SYNOPSIS...FRANKLIN/WCH

NEAR TERM...FRANKLIN/WCH

SHORT TERM...HITCHCOCK

LONG TERM...HITCHCOCK

AVIATION...FRANKLIN/WCH

MARINE...FRANKLIN/WCH

Delivered by Weather Underground Inc. Wed Jul 15 2015 9:35AM EDT