SPSPHI
FOR UPDATED INFORMATION ON THE TIMING AND MOVEMENT OF THIS LINE OF
STORMS.

TAKING A LOOK AT REGIONAL VISIBLE SATELLITE IMAGERY, IT APPEARS AS
THOUGH THERE ARE A FEW BREAKS IN THE CLOUDS TO OUR IMMEDIATE WEST
AND SOUTHWEST. THESE BREAK IN THE CLOUDS SHOULD ADVECT OVER THE
REGION IN THE NEXT COUPLE OF HOURS WHICH MAY HELP TO PRODUCE SOME
SURFACE BASED INSTABILITY BEFORE THE TRIPLE POINT COMES TO PASS.
WE WILL BE KEEPING AN EYE ON THIS AREA AS THE DAY GOES ON FOR THE
POTENTIAL OF MORE THUNDERSTORM DEVELOPMENT.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
THE DYNAMIC SYSTEM DISCUSSED ABOVE WILL BE LIFTING ACROSS OUR AREA
DURING THE EVENING WITH THE MAIN SURFACE LOW TRACKING TO OUR
NORTHWEST. WE WILL HAVE SOME SHOWERS AND POSSIBLE THUNDER QUICKLY
ROLLING ACROSS THE AREA TO START, HOWEVER THEN SOME DRYING ARRIVES
AS THE COLD FRONT SWEEPS TO OUR EAST. THE AIR MASS BEHIND THIS
SYSTEM HOWEVER IS NOT EXPECTED TO BE REAL COLD. WRAPAROUND MOISTURE
MAY BE ENHANCED SOME BY THE EASTERN GREAT LAKES, HOWEVER WITH A
DOWNSLOPING FLOW ON OUR SIDE OF THE MOUNTAINS, IT LOOKS LIKE THE
MAJORITY OF OUR CWA WILL BE DRYING OUT AS WE GO THROUGH TONIGHT.
PERHAPS A FEW SHOWERS ACROSS THE FAR NORTHERN ZONES WHERE ENOUGH
COOLING MAY ALLOW FOR SOME SNOW SHOWERS TO MIX IN LATE.

A CONCERN WE HAVE FOR MAINLY LATER TONIGHT IS THE WIND. AS THE
STORM SYSTEM WRAPS UP TO OUR NORTH, THE PRESSURE GRADIENT WILL BE
TIGHTENING UP AS HIGH PRESSURE IS WELL TO OUR WEST. THE 3-HOUR AND
6-HOUR PRESSURE FALLS ARE ON THE ORDER OF ABOUT 3-5 MB AND WE
WOULD LIKE TO SEE THESE HIGHER REGARDING STRONGER SURFACE WIND
POTENTIAL. STILL THOUGH, FORECAST SOUNDINGS INDICATE THAT THE FLOW
BETWEEN 900 MB AND 800 MB INCREASES TO 50 KNOTS OVERNIGHT. AS SOME
COLDER AIR ARRIVES ALOFT, THE LOW-LEVEL LAPSE RATES STEEPEN. THIS
WILL ALLOW FOR MORE EFFICIENT VERTICAL MIXING. THE QUESTION IS
JUST HOW MUCH MIXING OCCURS AS THE CAA IS NOT ALL THAT STRONG. FOR
NOW, WE WENT GENERALLY WITH GUSTS TO AROUND 25 KNOTS AND WILL
HOLD OFF ON ANY WIND HEADLINES GIVEN THE UNCERTAINTY AND NOT A
REAL IDEAL SETUP.

FOR SATURDAY, OUR WEATHER WILL BE DOMINATED BY A CYCLONIC FLOW AS
THE POTENT STORM LIFTS INTO THE CANADIAN MARITIMES. IT IS A GOOD
THING WE DO NOT HAVE A STRONG SURFACE HIGH BUILDING IN BEHIND THE
STORM OR WE WOULD BE MORE INCLINED TO ISSUE A HIGH WIND WATCH FOR
SATURDAY. AS IT STANDS NOW, IT LOOKS LIKE A WIND ADVISORY IS A GOOD
BET FOR SATURDAY. THE AIR MASS WILL STILL BE ON THE MILDER SIDE,
HOWEVER WITH PLENTY OF WIND WITHIN THE MIXING LAYER FOR MOST OF THE
DAY, BUFKIT PROFILES INDICATE GUSTS TO AROUND 35 KNOTS. IT WOULD
NOT BE SURPRISING TO SEE SOME LOCALLY HIGHER GUSTS, BUT SINCE THE
SURFACE HIGH IS NOT REAL STRONG TO OUR WEST AND THE PRESSURE RISES
ARE NOT REAL ROBUST, WIDESPREAD GUSTS TO 50 KNOTS DOES NOT APPEAR
LIKELY ATTM. AS A RESULT OF THIS AND THAT OUR CONFIDENCE IS NOT
HIGH, WE WILL HOLD OFF ON ISSUING A HIGH WIND WATCH FOR SATURDAY
BUT WILL DISCUSS THAT ADVISORY WINDS ARE A GOOD BET IN THE HWO.

THE WINDS WILL DIMINISH SATURDAY NIGHT AS HIGH PRESSURE SLIDES
EASTWARD AND LESSENS THE PRESSURE GRADIENT. THERE MAY STILL BE SOME
WRAPAROUND CLOUDINESS ESPECIALLY ACROSS OUR NORTHWESTERN ZONES,
HOWEVER THE LOWER LEVELS ARE FORECAST TO DRY OUT FURTHER. A
LESSENING WIND, DRIER AIR AND LESS CLOUDS WILL LEAD TO A CHILLY TO
COLD NIGHT. WE UTILIZED A FAIRLY EVENLY WEIGHTED BLEND BETWEEN MOS
AND CONTINUITY TO DERIVE TEMPERATURES.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
AN VERY ACTIVE PATTERN WILL CONTINUE, PARTICULARLY DURING THE FIRST
FEW DAYS. THE PREVIOUS STORM WILL BE SLIDING UP THROUGH THE CANADIAN
MARITIMES, WITH A NARROW AREA OF HIGH PRESSURE BUILDING IN ITS WAKE.
MEANWHILE, ADDITIONAL ENERGY THAT HAS BEEN DIGGING ACROSS THE WEST
IN THE SHORT TERM WILL ALREADY HAVE BEEN EJECTED INTO THE CENTRAL
PLAINS SUNDAY. THIS WESTERN ENERGY CONTINUES TO LOOKS RATHER
IMPRESSIVE AS A STRONG UPPER-LEVEL JET IS DRIVEN ACROSS THE
SOUTHWESTERN UNITED STATES. THIS FEATURE WILL ONCE AGAIN AMPLIFY THE
FLOW WITH A RIDGE BEING PUMPED UP AHEAD OF IT FOR A TIME, WHICH THEN
IS SHIFTED EASTWARD SUNDAY AS VERY STRONG UPPER-LEVEL TROUGH EJECTS
ACROSS THE CENTRAL PLAINS AND TOWARD THE OHIO VALLEY. THIS
UPPER-LEVEL TROUGH LOOKS TO EVOLVE INTO A RATHER BEAST OF A CLOSED
LOW IN THE EAST MONDAY INTO TUESDAY, AS A STRONG STORM SLAMS INTO
THE WEST ALLOWING A MASSIVE RIDGE TO BUILD ACROSS THE INTERIOR WEST.
THIS WILL FORCE ENERGY TO DIVE SOUTHEASTWARD OUT OF CENTRAL CANADA,
ALLOWING FOR ADDITIONAL AMPLIFICATION OF THE EASTERN TROUGH. THE
MODEL GUIDANCE IS IN PRETTY GOOD AGREEMENT OVERALL WITH THE LARGER
FEATURES, ALTHOUGH THE DEGREE OF AMPLIFICATION IS STILL BIT IN
QUESTION DUE MAINLY TO THE TIMING OF SHORT WAVE ENERGY. THIS IN
PARTICULAR LEADS TO SOME POTENTIAL DIFFERENCES IN THE DETAILS. IF
THE TRUE MORE AMPLIFIED SOLUTIONS OCCUR, THEN PERHAPS SOME BLOCKING
CAN DEVELOP, WHICH WOULD TEND TO SLOW DOWN THE WEATHER SYSTEMS
EASTWARD PROGRESSION. THIS SLOWER PROGRESSION IDEA COULD BE WHAT
OCCURS, AS THE ECMWF, UKMET AND CANADIAN GUIDANCE ALONG WITH THE
ECMWF AND CANADIAN ENSEMBLES CONTINUE TO INDICATE THAT A RATHER DEEP
EASTERN PACIFIC CLOSED LOW SHOULD PROGRESSES INTO THE WESTERN U.S.
AT A SLOWER RATE THAN FORECAST BY RECENT GFS AND GEFS ENSEMBLE MEAN
GUIDANCE. THIS WOULD HAVE A DOWNSTREAM AFFECT. ONE THING THAT LOOKS
CERTAIN IS THAT A RATHER ACTIVE PATTERN WILL OCCUR WITH THE DELIVERY
OF A CHILLY AIR MASS ACROSS THE ENTIRE REGION FOR THE FIRST PART OF
NEXT WEEK. PERHAPS WE MAY NEED SOME FROZE/FREEZE HEADLINES AT SOME
POINT.

WE GENERALLY DID NOT MAKE MANY CHANGES THROUGH THIS ENTIRE TIME
FRAME. A STRONG SURFACE LOW IS FORECAST TO BE SLIDING UP THROUGH THE
CANADIAN MARITIMES SUNDAY. OUR ENTIRE AREA WILL CONTINUE TO BE
WITHIN A CYCLONIC FLOW, HOWEVER THIS WILL EASE AS THE MAIN TROUGH
LIFTS OUT SOME AND A NARROW RIDGE MOVES ACROSS OUR AREA DURING
SUNDAY. THE NEXT SYSTEM WILL BE ARRIVING FAIRLY QUICKLY AS A STRONG
MID LEVEL FEATURE DRIVES YET ANOTHER SURFACE LOW JUST TO OUR WEST
AND NORTHWEST MONDAY. AS THE CASE WITH THE PREVIOUS EVENTS, A WARM
FRONT WILL BE RIDING NORTHWARD, HOWEVER THE MAIN SURFACE LOW IN THE
EASTERN GREAT LAKES REGION LOOKS TO OCCLUDE WITH ANOTHER SURFACE LOW
POTENTIALLY FORMING ON THE TRIPLE POINT. THIS FEATURE MAY THEN TRACK
RIGHT ACROSS OUR AREA MONDAY AND POTENTIALLY DEEPEN SIGNIFICANTLY AS
THE UPPER-LEVEL TROUGH AMPLIFIES. GIVEN THE STRENGTH OF THIS SYSTEM,
SOME HEAVIER RAIN MAY OCCUR WITH THE POTENTIAL FOR SOME CONVECTION.
REGARDING THE CONVECTIVE POTENTIAL, WE WILL HAVE TO SEE HOW THE
DETAILS DEVELOP AS THE SYSTEM MAY ARRIVE SOON ENOUGH TO LESSEN THE
INSTABILITY POTENTIAL. IF THERE IS INSTABILITY, IT MAY BE MORE
ELEVATED AS SOME COOLER LOW-LEVEL AIR MAY BE PRESENT. THIS WILL
ALL DEPEND ON THE TIMING OF THE SYSTEM AND THE PLACEMENT OF THE
WARM FRONT AND POSSIBLE SECONDARY DEVELOPMENT. THIS ENTIRE SYSTEM
THEN PIVOTS INTO FAR SOUTHEASTERN CANADA/NEW ENGLAND MONDAY NIGHT
AND TUESDAY AND DEEPENING AS IT DOES SO AS A LARGE UPPER-LEVEL
TROUGH DROPS ACROSS THE EAST. A GUSTY NORTHWESTERLY FLOW WILL BE
LEFT IN ITS WAKE WITH COLDER AIR BUILDING INTO THE AREA. WHILE THE
UPPER-LEVEL TROUGH IS BECOMING MORE AND MORE AMPLIFIED, SOME
EARLIER GUIDANCE THAT INDICATED THAT IT POSSIBLY BECOMES SOMEWHAT
NEGATIVELY TILTED, HAS BACKED OFF OF THAT IDEA AND HAS TRENDED MORE
TOWARD A STRONG CLOSED LOW EVOLVING. GIVEN THE ADVERTISED
AMPLIFICATION MONDAY AND MONDAY NIGHT, WE MAY HAVE A SHOT OF
ENHANCED PRECIPITATION. THE SCOPE AND PLACEMENT OF THE TRUE
AMPLIFICATION WILL DETERMINE WHERE THE SURFACE LOW TRACKS,
AFFECTING WHERE THE HEAVIEST PRECIPITATION OCCURS. AS THIS SURFACE
LOW WRAPS UP EAST OF JAMES BAY CANADA TUESDAY INTO WEDNESDAY,
GUSTY WINDS WILL CONTINUE AT TIMES. THE COLDER AIR ALOFT COUPLED
WITH THE HIGHER SUN ANGLE MAY TEAM UP WITH POSSIBLE SPOKES OF
ENERGY TO PRODUCE SOME SHOWERS ACROSS PARTS OF THE REGION. THIS
WOULD PROBABLY BE TUESDAY INTO WEDNESDAY. THE BULK OF THE
WRAPAROUND MOISTURE THOUGH MAY END UP MOSTLY NORTH OF OUR CWA,
HOWEVER THIS MAY HAVE TO BE WATCHED AS STEEPER LOW-LEVEL LAPSE
RATES MAY ALLOW FOR SOME CONVECTIVE-ISH SHOWERS /RAIN OR SNOW/.

GRADUALLY AN AREA OF HIGH PRESSURE SLIDING FROM THE CENTRAL PLAINS
TO THE GULF COAST WILL BUILD INTO OUR AREA THURSDAY. THIS SHOULD
TEND TO ALLOW FOR A MODERATING TREND. SOME 00Z MOSGUIDE DATA WAS
BLENDED IN, ESPECIALLY DEW POINTS, TEMPERATURES AND WINDS, TO
INTRODUCE SOME NEWER GUIDANCE INTO THE FORECAST. THAT IS ALL FOR
NOW. THANKS TO THE SURROUNDING OFFICES FOR THE COLLABORATION EARLY
THIS MORNING. HAVE A GOOD ONE!

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

ABOUT TO BE ISSUED TAFS WILL BE ENDING THE ORGANIZED CLUSTER OF
SHRAS AND TSRAS ACROSS OUR TERMINALS. WITH OUR CWA BRIEFLY
GETTING INTO THE WARM SECTOR CIGS AND VSBYS ARE EXPECTED TO RISE
ABOVE IFR LEVELS DURING THE AFTN, BUT CONFID WRT TO TIMING IS LOW.
SHOWERS AND TSRAS ASSOCIATED WITH THE OCCLUDED FRONT ITSELF DO NOT
HAVE AS MUCH SUPPORT ABOVE THE SURFACE FOR AN ORGANIZED LINE. THE
GREATEST INSTABILITY AT THE SURFACE IS EXPECTED TO REMAIN SE OF ALL
THE TERMINAL AREAS. SO WHILE THERE SHOULD BE SOME SHRAS WITH THE
FRONTAL PASSAGE ITSELF AND SOME ISOLATED THUNDER...THE THREAT IS NOT
HIGH ENUF AT ANY ONE SPECIFIC LOCATION TO CARRY TSRA IN THE TAFS.
ONCE THE OCCLUDED FRONT PASSES THIS EVENING...VFR CONDITIONS SHOULD
PREVAIL FOR THE REST OF THE TAF FORECAST PERIOD. WE DID MAINTAIN A
SC CIG THRU MOST OF THE NIGHT...BUT WOULD SUSPECT THAT IT WILL ERODE
FROM THE COAST INLAND AFTER MIDNIGHT. WE INCREASED WINDS
TONIGHT...BUT WENT BELOW SUGGESTED MAX GUST GUIDANCE BECAUSE ITS
OCCURRING OVERNIGHT AND FULL MIXING TO THE 5K LEVEL IS FORECAST TO
BE SPORADIC. ON SATURDAY DAY...WE DID FOLLOW THE FORECAST SOUNDINGS
PRETTY CLOSELY FOR MAX WIND GUSTS AS THE FORECAST SOUNDINGS DO SHOW
SOME THOROUGH MIXING. WE BELIEVE THAT WHILE SOME SC OR CU SHOULD
FORM...A VFR CIG IS NOT EXPECTED TO PREVAIL AT ANY TERMINAL SITES.

OUTLOOK...
WINDS WILL DECREASE SATURDAY NIGHT AND SUNDAY SHOULD FEATURE GOOD
FLYING CONDITIONS. BY MONDAY, ANOTHER SYSTEM LOOKS TO CAUSE A
DETERIORATION IN CONDITIONS AGAIN PROBABLY BACK TO IFR AT ITS HEIGHT
LATER MONDAY. GENERALLY VFR CONDITIONS ARE THEN EXPECTED BEHIND THE
SYSTEM FOR TUESDAY AND WEDNESDAY. THERE COULD BE SOME SHOWERS...BUT
THEIR DURATION SHOULD NOT BE LONG.

&&

.MARINE...
WINDS WERE INCREASING OVER THE SOUTHERN WATERS EARLY THIS MORNING,
WHILE NORTHERN WATER WINDS JUST BEGINNING TO INCREASE. ALTHOUGH THEY
ARE A SHADE BELOW GUIDANCE UP NORTH, THAT EVENTUALLY HAS TO GIVE AS
A NEGATIVE TILT MID LEVEL TROUGH IS POISED TO SWEEP OVER OUR WATERS
BY 00Z SATURDAY. THE ASSOCIATED SURFACE LOW DEEPENS RAPIDLY, AND WE
HAVE THE LACK OF STRONG HIGH PRESSURE AND STRONG COLD AIR ADVECTION
IN THE WAKE OF THE SYSTEM TO BE THANKFUL FOR.  RIGHT NOW WE ARE
THINKING THAT THE BULK OF OUR WATERS ARE COLD ENOUGH TO MAINTAIN A
MARINE LAYER AFTER THE LOW AND ASSOCIATED COLD FRONT PASS, BUT WE
BECOME LESS CERTAIN OF THIS AS WE MOVE TOWARD THE IMMEDIATE COAST,
ESPECIALLY NORTH. WE ARE GOING TO ISSUE A GALE WATCH FOR SATURDAY
INTO SATURDAY EVENING AND STAY WITH THE SMALL CRAFT ADVISORY PRIOR
TO THAT FOR OUR NORTHERN ATLANTIC WATERS. WE WILL BEGIN TO MENTION
OCCASIONAL GUSTS TO 35 KT OVER THE NORTHERN WATERS LATE TONIGHT.
ELSEWHERE ON THE ATLANTIC WATERS, WE WILL STAY WITH A STRONG SMALL
CRAFT FOR NOW. REGARDING DELAWARE BAY, WE WILL RUN A STRONG SMALL
CRAFT FROM THIS PACKAGE UNTIL 22Z SATURDAY AS WIND GUSTS WERE
BEGINNING TO EXCEED 20 KT. WE WILL LET THE DAY SHIFT REASSESS THE
STRENGTH OF THE MARINE LAYER, AND WE WILL MENTION OCCASIONAL GUSTS
TO 35 KT LATE FRIDAY NIGHT INTO SATURDAY WHERE WE ARE NOT RUNNING A
GALE WATCH.

WINDS AND SEAS SHOULD BEGIN TO RELAX SATURDAY NIGHT, BUT ANOTHER LOW
WILL AFFECT THE WATERS BEGINNING SUN NIGHT. LATEST GUIDANCE WOULD
SUGGEST THE BRUNT OF THE WINDS AND SEAS WOULD ARRIVE MONDAY NIGHT.

&&

.TIDES/COASTAL FLOODING...
WE ARE JUST COMING OUT OF NEAP TIDES, AND WOULD NEED NEGATIVE
DEPARTURES OF 1.5 TO 2.0 FEET TO CAUSE BLOWOUT TIDES SATURDAY INTO
SUNDAY. OUR GUIDANCE, WHICH OFTEN HAS A NEGATIVE BIAS, IS ONLY
FORECASTING NEGATIVE DEPARTURES FROM ABOUT 1.0 TO 1.5 FEET. FOR NOW,
IT SEEMS THAT A LOW WATER ADVISORY WOULDN`T BE NEEDED, BUT WE WILL
MONITOR.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR ANZ430-431-
     452>455.
     GALE WATCH FROM SATURDAY MORNING THROUGH SATURDAY EVENING FOR
     ANZ450-451.
     SMALL CRAFT ADVISORY UNTIL 6 AM EDT SATURDAY FOR ANZ450-451.

&&

$$
SYNOPSIS...GORSE