914 FXUS61 KBGM 160844 AFDBGM AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BINGHAMTON NY 444 AM EDT FRI MAY 16 2014 .SYNOPSIS... A COLD FRONT WILL CONTINUE TO SLOWLY MARCH EAST ACROSS THE AREA TODAY. THIS FEATURE WILL BE ACCOMPANIED BY A WIDESPREAD SOAKING RAIN FOR ALL OF CENTRAL NEW YORK AND NORTHEASTERN PENNSYLVANIA. THE RAIN COULD BE HEAVY AT TIMES TODAY AS DEEP TROPICAL MOISTURE INTERACTS WITH THE MAIN FRONTAL BOUNDARY. BEHIND THE FRONT...COOLER AND DRIER WEATHER IS IN STORE FOR THE UPCOMING WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... FLASH FLOOD WATCH REMAINS IN EFFECT FOR THE ENTIRE FORECAST AREA TODAY AS SUBTROPICAL MOISTURE CONTINUES TO ADVANCE NORTH IN STRONG SOUTHERLY FLOW ALOFT. BLENDED TPW SATELLITE DATA SHOWING PWAT VALUES IN EXCESS OF 1.5" ACROSS MUCH OF THE AREA WHICH IS ROUGHLY 200% OF NORMAL FOR THIS TIME OF YEAR. MAIN COLD FRONT SLOWLY ADVANCING EAST THIS HR WITH LATEST OBS SUGGESTING FEATURE NOW RESIDES ACROSS THE CENTRAL FINGER LAKES. AS ALLUDED TO IN THE EARLIER UPDATE...00Z MODEL GUIDANCE IS SIGNIFICANTLY DIFFERENT THAN PREVIOUS RUNS AS THE LATEST SUITE INDICATES TODAY/S RAINFALL EVENT WILL BE MORE PROGRESSIVE THAN PREVIOUSLY THOUGHT. THE MAIN REASONING BEHIND THIS APPEARS TO BE WELL UPSTREAM ACROSS THE WESTERN GREAT LAKES/LWR OHIO VLY WHERE MAIN UPPER LOW CONTINUES TO SPIN THIS MORNING. WITH TODAY/S SUITE...MODELS ARE INSISTENT THAT TWO SEPARATE UPPER LOWS WILL FAIL TO CONSOLIDATE...RESULTING IN A GRADUAL NEGATIVE TILT ORIENTATION OF THE DEEP UPPER WAVE AS THE DAY PROGRESSES. AS FEATURE GOES NEGATIVE...EASTWARD PROGRESSION OF DOWNSTREAM COLD FRONT IS EXPECTED AS MAIN SFC LOW LIFTS NORTH INTO QUEBEC AS A SECONDARY LOW RIDING UP THE FRONT MOVES NORTH INTO THE LOWER MID- ATLANTIC REGION. LATEST REGIONAL RADAR TRENDS ALREADY SHOWING STEADY EASTWARD PROGRESSION THIS MORNING WHICH WILL HOPEFULLY LIMIT THE DURATION OF HEAVY RAINS OVER A PARTICULAR AREA. WITH THE ABOVE SAID...WIDESPREAD CONCERNS FOR SIGNIFICANT HYDRO RELATED PROBLEMS APPEARS TO BE LOWER THIS MORNING BASED PURELY ON THE FASTER PROGRESSION OF THE MAIN FRONT. THAT'S NOT TO SAY WE STILL WON/T HAVE SOME PROBLEMS AS A GENERAL 1-2" OF RAIN STILL APPEARS POSSIBLE BEFORE RAIN COMES TO AN END FROM WEST TO EAST BY MID/LATE AFTERNOON FOR AREAS WEST OF I-81...AND BY EARLY EVENING FOR AREAS EAST. FOR NOW HOWEVER...MAIN AREA OF CONCERN REMAINS THE CENTRAL FINGER LAKES REGION WHERE SOILS REMAIN SATURATED FROM HEAVY RAINS/FLOODING FROM TUESDAY NIGHT. ON-LINE SCANNER REPORTS ALREADY INDICATING FLOODING IN YATES COUNTY AND A FLASH FLOOD WARNING HAS BEEN ISSUED DUE TO QUICK RESPONDING ANTECEDENT SOIL CONDITIONS. VERY TOUGH CALL WITH RESPECT TO QPF FCST AS FASTER PROGRESSION OF MAIN FRONTAL BAND WILL LIMIT RAINFALL DURATION. THAT SAID...WELL- ESTABLISHED TROPICAL MOISTURE CONNECTION DEFIANTLY IN PLACE WITH EXCELLENT UPPER JET DYNAMICS DIRECTLY OVERHEAD. THIS COMBINED WITH GOOD LOW-LEVEL MOISTURE CONVERGENCE WILL ALLOW AMPLE LIFT FOR ONGOING SHWR ACTIVITY. AS A RESULT...NO CHANGES PLANNED FOR CURRENT FLASH FLOOD WATCH HEADLINE. && .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... 245 AM UPDATE... PERIOD OF BELOW CLIMATOLOGY TEMPERATURES THIS WEEKEND...AS OUR WEATHER IS DOMINATED BY A COOL UPPER LEVEL TROUGH THAT SLOWLY SHIFTS THROUGH THE REGION. AFTER THE CONTINUED STRONG COLD AIR ADVECTION OF FRIDAY NIGHT...850MB TEMPERATURES THROUGH THE WEEKEND WILL BE BETWEEN ZERO AND 5 DEGREES ABOVE ZERO CELSIUS. THE 540 DECAMETER THICKNESS LINE WILL ALSO BE STRADDLED OVER THE AREA. UPPER TROUGH AXIS WILL GRADUALLY SHIFT FROM THE WESTERN GREAT LAKES TO THE EASTERN GREAT LAKES OVER THE COURSE OF THE WEEKEND. THAT COLD AIR ALOFT...COMBINED WITH DAYTIME HEATING VIA THE HIGH MID MAY SUN ANGLE...WILL YIELD STEEP LAPSE RATES AND ISOLATED TO SCATTERED DIURNALLY DRIVEN SHOWERS. BEST CHANCE FOR THESE BOTH AFTERNOONS WILL BE IN THE CENTRAL TWIN TIERS TO FINGER LAKES REGION...BUT EVEN IN THESE LOCATIONS THE VAST MAJORITY OF THE TIME WILL BE DRY...AND RAIN AMOUNTS WILL BE ON THE ORDER OF A FEW HUNDREDTHS OF AN INCH. EVEN WHERE RAIN DOES NOT OCCUR...WE SHOULD SEE CONVECTIVE LOOKING CLOUDS DEVELOP BOTH DAYS. HIGHS SATURDAY AND SUNDAY WILL BE MAINLY UPPER 50S TO MID 60S. SATURDAY NIGHT AND SUNDAY NIGHT...ANTICIPATING LOWS IN THE MID 30S TO LOW 40S. WE MAY NEED TO HOIST FROST ADVISORIES FOR PORTIONS OF THE AREA EACH NIGHT. SATURDAY NIGHT THERE WILL STILL BE SOME GRADIENT WIND...SUNDAY NIGHT LESS WIND YET ALSO SOME CLOUDS ATTEMPTING TO MOVE IN FROM THE WEST TOWARDS DAWN. WHILE FROST POTENTIAL WILL EXIST BOTH NIGHTS...ESPECIALLY TWIN TIERS NORTHWARD...THE BEST CHANCE FOR IT APPEARS TO BE SUNDAY NIGHT BECAUSE OF EXPECTED DURATION OF RADIATIONAL COOLING. && .LONG TERM /MONDAY THROUGH THURSDAY/... 200 PM UPDATE...UPPER LEVEL TROF AXIS WILL BE IN THE PROCESS OF MOVING EAST AND CUTTING OFF OVER THE ATLANTIC OCEAN SUNDAY NIGHT. WHILE THE BEST SHOT FOR SHOWERS WILL BE EAST OF THE FORECAST AREA, WE WILL BE CLOSE ENOUGH TO WARRANT A LOW CHANCE FOR SHOWERS THROUGH MONDAY NIGHT ESPECIALLY EAST OF I-81. OUR AREA WILL BE IN A RIDGE OF HIGH PRESSURE WILL NICE WEATHER TUESDAY AND WEDNESDAY BEFORE THE DEVELOPING NORTHWEST FLOW SENDS ANOTHER UPPER LEVEL LOW OUR WAY. TEMPS WILL BE NEAR NORMAL, OR UPPER 60S TO NEAR 70 DURING THE PERIOD. && .AVIATION /08Z FRIDAY THROUGH TUESDAY/... 06Z UPDATE... DETERIORATING CONDITIONS EXPECTED THIS MORNING AS MOIST FRONT SLOWLY TRUDGES ACROSS THE TERMINALS. INITIAL VFR OR HIGH END MVFR CIGS WILL DEGRADE TO FUEL ALT MVFR AND OCCASIONAL IFR CIG OR VIS AS AXIS OF HEAVIER SHOWERS MOVES THROUGH MAINLY AFTER 12Z /POSSIBLY SOONER KBGM-KELM/. ISOLATED LIGHTNING STRIKE POSSIBLE...BUT OVERALL NOT EXPECTING ENOUGH THUNDER TO INCLUDE IN TAFS...MAINLY JUST A SOLID RAIN. INITIAL SE FLOW WILL VEER SW TO WNW WITH TIME WITH SLOW PASSAGE OF THE FRONT DURING THE DAY...SEE TAFS FOR SPECIFICS ON TIMING. ALSO...KELM AND KRME MARGINAL LLWS EARLY THIS MORNING DUE TO SOUTHERLY 40 KT JET AT 2 KFT AGL VERSUS ESE OR VARIABLE WIND AT SURFACE. BEHIND THE FRONT...RAIN SHOWERS END BUT MVFR CIG SHOULD PERSIST FOR MOST TERMINALS INTO EVENING. OUTLOOK... SAT/SAT NGT...MAINLY VFR...THOUGH LINGERING MVFR CIG POSSIBLE EARLY SAT MORNING. SUN/MON...MAINLY VFR...BUT BRIEF RESTRICTIONS POSSIBLE IN ISO -SHRA. TUE...VFR. && .HYDROLOGY... 8 PM MONDAY UPDATE... FLASH FLOOD WATCH FOR ENTIRE CWA LATE TONIGHT THROUGH FRIDAY. MOST LIKELY SCENARIO FOR ISOLATED FLASH FLOODING DUE TO RAINFALL RATES OF HALF AN INCH AN HOUR DUE TO EMBEDDED THUNDERSTORMS. WIDESPREAD SOAKING RAIN OF 1.5 TO 2.5 INCHES COULD CAUSE MINOR FLOODING AT A FEW HEADWATER RIVER POINTS FROM ONEIDA TO DELAWARE COUNTIES IN NY FRIDAY. ISOLATED RAINFALL AMOUNTS COULD BE HIGHER. MOST PRONE AREA FOR FF IS THE CENT SRN TIER AND FINGER LAKES OF NY WHERE ISOLATED HEAVY RAIN FELL MONDAY AND TUESDAY NIGHTS. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR PAZ039-040-043-044- 047-048-072. FLASH FLOOD WATCH THROUGH THIS EVENING FOR PAZ038. NY...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR NYZ009-018-036-037- 044>046-056-057-062. FLASH FLOOD WATCH THROUGH THIS EVENING FOR NYZ015>017-022>025- 055. && $$ SYNOPSIS...CMG/MDP NEAR TERM...CMG/PVN/TAC SHORT TERM...MDP LONG TERM...HEDEN AVIATION...MDP HYDROLOGY...