Flash Flood Watch 1, NWS Buffalo, NY

189 
WGUS61 KBUF 122212
FFABUF

FLOOD WATCH
NATIONAL WEATHER SERVICE BUFFALO NY
612 PM EDT FRI JUN 12 2015

NYZ003>008-013-014-021-122315-
/O.CAN.KBUF.FF.A.0001.000000T0000Z-150613T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MONROE-WAYNE-NORTHERN CAYUGA-OSWEGO-JEFFERSON-LEWIS-LIVINGSTON-
ONTARIO-ALLEGANY-
INCLUDING THE CITIES OF...ROCHESTER...NEWARK...FAIR HAVEN...
OSWEGO...WATERTOWN...LOWVILLE...GENESEO...CANANDAIGUA...
WELLSVILLE
612 PM EDT FRI JUN 12 2015

...FLASH FLOOD WATCH IS CANCELLED...

THE FLASH FLOOD WATCH FOR PORTIONS OF CENTRAL AND WESTERN NEW
YORK HAS BEEN CANCELLED. THE HEAVIEST RAINS HAVE EXITED THE
AREA...AND WITH NO MORE SIGNIFICANT RAINFALL EXPECTED...THE FLOOD
THREAT NO LONGER EXISTS.

$$

WOOD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
751 AM EDT FRI JUN 12 2015

.SYNOPSIS...
A WARM FRONT WILL LIFT ACROSS NEW YORK EARLY TODAY...BRINGING A
RETURN TO WARMER AND MORE HUMID CONDITIONS. A ROUND OF STRONG TO
POTENTIALLY SEVERE THUNDERSTORMS AND HEAVY RAINFALL IS POSSIBLE
THIS AFTERNOON AND TONIGHT AS LOW PRESSURE CROSSES THE EASTERN
GREAT LAKES. HIGH PRESSURE WILL BRING MAINLY DRY AND SUNNY WEATHER
FOR THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
'SNEAKY' WARM FRONTAL CONVECTION AIDED BY A WEAK IMPULSE RIDING
THROUGH THE EASTERN GREAT LAKES PUSHING ACROSS THE BUFFALO TO
ROCHESTER CORRIDOR EARLY THIS MORNING. THIS ACTIVITY WILL LIFT
NORTHEAST THIS MORNING MAINLY IMPACTING SOUTHERN ONTARIO...
ALTHOUGH SOME OF THIS ACTIVITY COULD LINGER ACROSS LAKE ONTARIO
AND THE NORTH COUNTRY.

A WARM AND MORE HUMID AIRMASS WILL BE IN PLACE TODAY WITH
TEMPERATURES RISING INTO THE 80S AS A POOL OF WARM SECTOR +18C AIR
AT 850 MB MOVES OVERHEAD. THIS WARM AIR CAP SHOULD HELP KEEP MUCH OF
THE REGION RAIN FREE MUCH OF THE DAY...AFTER THE EARLY MORNING
CONVECTION...WITH INCREASING CHANCES OF SHOWERS AND THUNDERSTORMS
DEVELOPING ALONG LAKE BREEZE BOUNDARIES DURING THE AFTERNOON AHEAD
OF THE LARGER SCALE SYNOPTIC FORCING FROM THE APPROACHING SURFACE
LOW. PRECIPITABLE WATER VALUES RISING TOWARD 1.8 INCHES WILL BRING A
THREAT FOR SOME HEAVY DOWNPOURS WITH A MORE CONCERNING THREAT FOR
SEVERE THUNDERSTORMS COMING TOWARD THE EVENING HOURS AS THE SURFACE
LOW GETS A BIT CLOSER.

TONIGHT...INSTABILITY AXIS WILL RESIDE ACROSS THE REGION. MOIST WARM
SECTOR ENVIRONMENT WILL SUPPORT MIXED LAYER CAPE VALUES OF 1000-1500
J/KG EARLY ON. SURFACE LOW WILL RIPPLE ALONG THE BAROCLINIC ZONE
SUPPORTING LOCALLY ENHANCED 0-1 KM STORM RELATIVE HELICITY VALUES OF
200 M2/S2 OR SO IN THE PRESENCE OF 40 KNOTS 0-6 KM DEEP LAYER BULK
SHEAR AND A LOWER LCL ENVIRONMENT. POTENTIAL FOR SUPERCELLS CAPABLE
OF GENERATING TORNADOES WILL EXIST...IN ADDITION TO DAMAGING WIND
AND HAIL. A STRONG MID-LEVEL FLOW OF 50 KTS ACROSS THE INITIATING
BOUNDARY WILL FAVOR SOME POTENTIAL FOR REAR INFLOW JETS/CONVECTIVE
AUGMENTATION OF ENVIRONMENTAL WINDS SUCH THAT AN EVOLUTION TOWARD
BOWING SEGMENTS SEEMS A REASONABLE SCENARIO AS WELL.

THE FRONT LOOKS TO ORIENT PARALLEL TO THE DEEP LAYER MEAN FLOW A
BIT LATER IN THE NIGHT...POTENTIALLY SETTING UP A FEW/SEVERAL
HOURS OF POTENTIAL TRAINING WHICH COULD BRING THE RISK OF LOCALLY
HEAVY RAINFALL AND AN ENHANCED FLOOD RISK. THIS MAY BECOME A
GREATER CONCERN FOR AREAS WHICH HAVE SEEN HEAVIER RAINS IN RECENT
DAYS ACROSS PORTIONS OF THE GENESEE VALLEY AND FINGER LAKES
INCLUDING THE ROCHESTER AREA. CONVECTIVE TRENDS WILL NEED TO BE
MONITORED CLOSELY.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
AS HIGH PRESSURE MOVES ACROSS SOUTHERN ONTARIO...EXPECT THE FRONTAL
BOUNDARY TO STALL JUST SOUTH OF THE NY/PA STATE LINE ON SATURDAY.
THIS SHOULD RESULT IN MOSTLY DRY WEATHER...WITH A SMALL CHANCE FOR
SHOWERS TO LINGER ACROSS FAR SOUTHERN PORTIONS OF THE CWA. HIGHS ON
SATURDAY SHOULD BE IN THE MID TO UPPER 70S.

THIS WEAK BOUNDARY SHOULD GRADUALLY LIFT NORTH TOWARD THE REGION
LATE SATURDAY NIGHT AND SUNDAY IN RESPONSE TO A STRENGTHENING UPPER
LEVEL RIDGE ACROSS OUR REGION. THIS MAY RESULT IN A SHOWER OR
THUNDERSTORM...BUT AREAL COVERAGE SHOULD BE SPARSE WITH THE MAJORITY
OF THE REGION EXPECTED TO REMAIN DRY ON SUNDAY. MAY SEE MOST
DEVELOPMENT ALONG LAKE ERIE BREEZE SOUTH OF METRO BUFFALO. THIS
PATTERN WILL ALSO BRING WARMER AIR INTO THE REGION...WITH HIGHS IN
THE UPPER 70S TO LOWER 80S ON SUNDAY.

A STRONGER WARM SURGE LIFTING NORTHEASTWARD ACROSS THE REGION SUNDAY
NIGHT AND MONDAY WILL LEAD TO A STORMY AND WET PATTERN FOR MONDAY
AND MONDAY NIGHT. PRECIPITABLE WATER VALUES NEARLY 2 INCHES MONDAY
EVENING INDICATED POTENTIAL FOR HEAVY RAINS ASSOCIATED WITH
THUNDERSTORMS. HIGH TEMPS ON MONDAY SHOULD REACH THE UPPER 70S TO
LOWER 80S.

&&

.LONG TERM /TUESDAY THROUGH THURSDAY/...
MODEL GUIDANCE DIFFERS ON TIMING...BUT THE 12Z GFS/GGEM/ECMWF ARE IN
AGREEMENT THAT A WARM FRONT WILL GRADUALLY LIFT ACROSS THE REGION
LATE SUNDAY NIGHT OR MONDAY. THERE IS A GOOD CHANCE THAT THIS WILL
PRODUCE SHOWERS AND THUNDERSTORMS WITH ITS PASSAGE. THIS ALSO WILL
BRING WARMER AND RELATIVELY MUGGY AIR INTO THE REGION FOR MONDAY.

AFTER THIS THERE WILL BE A RELATIVELY ZONAL FLOW WITH THE JET AXIS
ACROSS SOUTHERN CANADA. A SHORTWAVE EMBEDDED IN THIS FLOW SHOULD
TRACK TO OUR NORTH ON TUESDAY WHICH WILL PUSH THE FRONTAL BOUNDARY
BACK SOUTHWARD AS A COLD FRONT. TEMPERATURES WILL DROP SLIGHTLY
TUESDAY...WITH A LINGERING CHANCE FOR SHOWERS OR THUNDERSTORMS AS
THE FRONT GRADUALLY SAGS SOUTHWARD.

THE BEST CHANCE FOR DRY WEATHER IS TUESDAY NIGHT AND WEDNESDAY SINCE
THE 12Z GFS/ECMWF BOTH BUILD HIGH PRESSURE ACROSS THE REGION. GIVEN
THE WEAK PUSH BEHIND THE FRONT...THERE STILL IS A SMALL CHANCE THE
BOUNDARY WILL LINGER...BUT GIVEN THIS CONSENSUS WILL GO WITH A DRY
FORECAST DURING THIS PERIOD WITH SEASONABLE TEMPERATURES IN THE MID
TO UPPER 70S EXPECTED WEDNESDAY. THEN ANOTHER WEAK SHORTWAVE IS
FORECAST TO APPROACH THE REGION THURSDAY...WITH A SMALL CHANCE FOR
SHOWERS AND THUNDERSTORMS.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
SCATTERED CONVECTION NORTH OF AN APPROACHING WARM FRONT COULD
IMPACT ALL SITES THIS MORNING WITH LOCAL CONDITIONS BRIEFLY LOWER
TO IFR IN ANY HEAVIER SHOWERS.

ONCE THE WARM SECTOR IS REALIZED ACROSS THE AREA THIS
AFTERNOON...AN INCREASINGLY MOIST AND UNSTABLE AIRMASS WILL
RESULT IN THE DEVELOPMENT OF SCT -SHRA/-TSRA INITIALLY ALONG LAKE
BREEZES BY AROUND 18Z.

-SHRA/-TSRA COVERAGE WILL BECOME WIDESPREAD BY 00Z AS A LOW PRESSURE
SYSTEM CROSSES THE REGION. ACCOMPANIED BY A LOW-LEVEL JET...SOME OF
THESE THUNDERSTORMS WILL HAVE THE POTENTIAL TO BE STRONG TO SEVERE
WITH THE POTENTIAL FOR BOWING LINE SEGMENTS AND ROTATING CELLS.

OUTLOOK...
SATURDAY AND SATURDAY NIGHT...MAINLY VFR.
SUNDAY...MAINLY VFR WITH A CHANCE OF SHOWERS FAR WEST.
MONDAY AND TUESDAY...MAINLY VFR WITH A CHANCE OF SHOWERS AND
THUNDERSTORMS.

&&

.MARINE...
LIGHT WINDS WILL PERSIST THIS MORNING AS A WEAK AREA OF HIGH
PRESSURE CROSSES NEW YORK AND A WARM FRONT LIFTS ACROSS THE EASTERN
GREAT LAKES. A MOISTURE LADEN LOW PRESSURE SYSTEM WILL APPROACH THE
AREA THIS EVENING WITH ANOTHER ROUND OF STRONG TO POTENTIALLY SEVERE
THUNDERSTORMS. WHILE THESE STORMS MAY BRING BRIEF PERIODS OF LOCALLY
STRONG AND POTENTIALLY DAMAGING WINDS...OVERALL WINDS SHOULD REMAIN
LIGHT ENOUGH TO PRECLUDE ISSUANCE OF ANY SMALL CRAFT ADVISORIES
FRIDAY.

HIGH PRESSURE WILL THEN BUILD IN QUICKLY BEHIND THE FRONT...
RESULTING IN TRANQUIL CONDITIONS ON THE LAKES FOR THIS WEEKEND.
ANOTHER WARM FRONT IS EXPECTED TO LIFT ACROSS THE LAKES SUNDAY
NIGHT OR MONDAY...BRINGING ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS MONDAY INTO TUESDAY.

&&

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

&&

SYNOPSIS...TMA
NEAR TERM...TMA
SHORT TERM...WCH
LONG TERM...APFFEL
AVIATION...TMA
MARINE...TMA

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BUFFALO NY
500 AM EDT FRI JUN 12 2015

NYZ001>008-010>014-019>021-085-130900-
NIAGARA-ORLEANS-MONROE-WAYNE-NORTHERN CAYUGA-OSWEGO-JEFFERSON-
LEWIS-NORTHERN ERIE-GENESEE-WYOMING-LIVINGSTON-ONTARIO-CHAUTAUQUA-
CATTARAUGUS-ALLEGANY-SOUTHERN ERIE-
500 AM EDT FRI JUN 12 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL NEW
YORK AND WESTERN NEW YORK.

.DAY ONE...TODAY AND TONIGHT.

THUNDERSTORMS ARE EXPECTED TO MOVE ACROSS THE REGION LATE THIS AFTERNOON
AND TONIGHT. SOME OF THESE STORMS MAY BECOME SEVERE WITH DAMAGING
WINDS AND LARGE HAIL. THUNDERSTORMS MAY ALSO PRODUCE HEAVY
RAINFALL AND FLOODING.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.

THE CHANCE FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...

LEZ020-040-041-LOZ030-042>045-062>065-SLZ022-024-130900-
UPPER NIAGARA RIVER AND BUFFALO HARBOR-
LAKE ERIE NEARSHORE WATERS FROM RIPLEY TO DUNKIRK-
LAKE ERIE NEARSHORE WATERS FROM DUNKIRK TO BUFFALO-
LOWER NIAGARA RIVER-
LAKE ONTARIO NEARSHORE WATERS FROM THE NIAGARA RIVER TO HAMLIN
BEACH-
LAKE ONTARIO NEARSHORE WATERS FROM HAMLIN BEACH TO SODUS BAY-
LAKE ONTARIO NEARSHORE WATERS FROM SODUS BAY TO MEXICO BAY-
LAKE ONTARIO NEARSHORE WATERS FROM MEXICO BAY TO THE SAINT
LAWRENCE RIVER-
LAKE ONTARIO OPEN WATERS FROM THE NIAGARA RIVER TO HAMLIN BEACH-
LAKE ONTARIO OPEN WATERS FROM HAMLIN BEACH TO SODUS BAY-
LAKE ONTARIO OPEN WATERS FROM SODUS BAY TO MEXICO BAY-
LAKE ONTARIO OPEN WATERS FROM MEXICO BAY TO THE SAINT LAWRENCE
RIVER-SAINT LAWRENCE RIVER FROM CAPE VINCENT TO OGDENSBURG-
SAINT LAWRENCE RIVER FROM OGDENSBURG TO SAINT REGIS-
500 AM EDT FRI JUN 12 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF LAKE ERIE...
LAKE ONTARIO AND SAINT LAWRENCE RIVER.

.DAY ONE...TODAY AND TONIGHT.

THUNDERSTORMS ARE EXPECTED TO MOVE ACROSS THE REGION LATE THIS AFTERNOON
AND TONIGHT. SOME OF THESE STORMS MAY BECOME SEVERE WITH DAMAGING
WINDS AND LARGE HAIL.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.

THE CHANCE FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...