000 FXUS61 KBGM 261137 AFDBGM AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BINGHAMTON NY 737 AM EDT THU JUL 26 2007 .SYNOPSIS... AN UPPER LEVEL LOW PRESSURE SYSTEM OVER OHIO...WILL BRING A FEW SHOWERS AND THUNDERSTORMS...PRIMARILY WEST OF THE INTERSTATE 81 CORRIDOR...FOR TODAY. BY FRIDAY...THIS SYSTEM WILL BEGIN TO MOVE EAST AND COMBINE WITH AN APPROACHING COLD FRONT...TO INCREASE THE CHANCES FOR SHOWERS AND THUNDERSTORMS. THIS UNSETTLED WEATHER WILL LAST INTO THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... PRETTY MUCH A CARBON COPY OF YESTERDAY WITH THE PESKY UPPER LOW CONTINUING TO ROTATE NEAR KDTX TODAY. ONE DIFFERENCE THIS MORNING IS A MARINE LAYER THAT IS ATTEMPTING TO PUSH INTO MY SOUTHEASTERN ZONES. FEEL THAT THIS WILL MAKE A LITTLE MORE HEADWAY AS WE MOVE TOWARDS DAWN...BUT THEN ERODE UNDER STRONG JULY SUN DURING THE EARLY MORNING HOURS. VALLEY FOG IS ALSO FORMING ATTM...AND WILL BE A LITTLE MORE WIDESPREAD THAN YESTERDAY MORNING...BUT WILL STILL BURN OFF PRETTY QUICKLY AS THE SUN RISES. EXPECT PSUNNY SKIES THROUGHOUT THE AREA TODAY WITH PLENTY OF DIURNAL CU. WITH A LITTLE MORE LOW LEVEL MOISTURE THAN YESTERDAY...BELIEVE MORE OF THE AREA IS AT RISK FOR A FEW SHRA/TSRA...BUT STILL DONT FEEL COVERAGE WILL BE THAT GREAT. WITH T850 APPROACHING 16C...EXPECT HIGHS TO BE A FEW DEGREES WARMER THAN YESTERDAY...LIKELY A LITTLE CLOSER TO THE WARMER MAV GUIDANCE THAN THE MET...ALBEIT A DEGREE OR TWO COOLER THAN THE MAV HIGHS. && .SHORT TERM /FRIDAY THROUGH SATURDAY/... A PRETTY SULTRY NIGHT IS IN STORE TONIGHT...WITH A DECENT BIT OF CLOUD COVER...ALONG WITH LOTS OF LOW LEVEL MOISTURE...HELPING TO KEEP TEMPS UP. ANY SHRA/TSRA ACTIVITY REMAINING FROM THIS AFTERNOON WILL DISSIPATE BY LATE EVENING. RH PROFILES SUGGEST THAT THERE MAY BE MORE OF A MARINE INFLUENCE THAN WE SAW TONIGHT...SO WILL KEEP SKIES PCLOUDY...AND THE DAY SHIFT WILL HAVE TO REASSESS WHETHER ANY LOW BKN CLOUDS WILL WORK IN...AS THEY TRIED TO TONIGHT. ON FRIDAY...WELL FINALLY SEE THE UPPER LOW WEST OF US BEGIN TO GET KICKED EASTWARD DUE TO A SHORTWAVE MOVING THROUGH SOUTHERN CANADA. THE APPROACH OF THE UPPER LOW WILL ADD SOME WEAK HEIGHT FALLS...ALONG WITH SOME COOLING ALOFT TO A VERY MOIST/WARM SFC AIRMASS. THIS SHOULD INCREASE THE INSTABILITY ENOUGH TO GET PRETTY WIDESPREAD SHRA/TSRA ACTIVITY GOING ACROSS THE CWA. CAPE VALUES FROM THE GFS ARE IMPRESSIVE...NEAR 1500 J/KG WITH THE NAM A LITTLE LESS THAN 1000 J/KG. SHEAR WILL NOT BE IMPRESSIVE...WITH 0-6KM VALUES STRUGGLING TO GET MUCH ABOVE 20KTS. SO...EXPECT A FEW PULSE SEVERE STORMS...BUT IT DOESNT LOOK LIKE A WIDESPREAD SEVERE EVENT AT THIS TIME. WITH PWATS APPROACHING 1.5 INCHES...AND MBE VECTORS AT 5KTS OR LESS IN THE AFTERNOON /AND EVEN SHOWING A WEAK NW PROPAGATION/...COULD SEE SOME SLOW-MOVING HEAVY DOWNPOURS. FRIDAY NIGHT...WITH THE UPPER LOW NEARLY OVERHEAD...FEEL THAT WELL SEE SOME LEFTOVER CONVECTIVE ACTIVITY THROUGH THE NIGHT. TEMPS WILL AGAIN BE QUITE WARM...LIKELY NEAR 65F. SATURDAY THE UPPER LOW WILL EJECT NORTHEAST AS MORE ENERGY DROPS INTO WHAT WILL BECOME A PRETTY STUBBORN EAST COAST TROUGH. AT THE SURFACE...A COLD FRONT WILL APPROACH FROM THE NORTHWEST. THIS...COMBINED WITH THE JUICY AIRMASS IN PLACE SHOULD SPELL ANOTHER DAY OF SHRA/TSRA. HOWEVER...WITH A STABILIZING AIRMASS APPROACHING FROM THE NORTHWEST...FEEL THE BEST CHANCES FOR THUNDER WILL BE OVER SOUTHEASTERN AREAS. CAPE VALUES IN THESE AREAS WILL BE SIMILAR TO THOSE ON FRIDAY...WITH WEAK SHEAR AGAIN. SO...SOME PULSE SEVERE STORMS AGAIN LOOK POSSIBLE. THE HEAVY RAIN THREAT WILL ALSO CONTINUE...WITH PWATS OVER 1.5 AND THE GFS SHOWING NEARLY STATIONARY MBE VECTORS. THE FLASH FLOOD THREAT WILL HAVE TO BE WATCHED...AND WILL LIKELY BE TIED TO HOW MUCH RAIN FALLS ON FRIDAY. THE GFS STILL STALLS THE FRONTAL BOUNDARY OVER OUR SOUTHEASTERN ZONES SUNDAY...AND IN TONIGHTS 00Z RUN /SUPPORTED BY THE 00Z CANADIAN GEM/...ACTUALLY DEVELOPS A WAVE OF LOW PRESSURE ALONG THIS BOUNDARY...BRINGING A POTENT SLUG OF RAIN TO THE AREA FOR MONDAY. THE SLOWING SEEMS REASONABLE GIVEN THE BLOCKING PATTERN IN PLACE OFF THE NEW ENGLAND COASTLINE. HOWEVER...THE FINAL LOCATION OF THE BAROCLINIC ZONE...AND WHEN/IF A LOW DEVELOPS ALONG IT ARE DETAILS THAT WILL LIKELY CHANGE AS WE NEAR THE EVENT. STAY TUNED HOWEVER...AS A PROLONGED PERIOD OF HEAVY RAIN IS POSSIBLE. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... FOLLOWED HPC GUIDANCE THRU PD. FORECAST PROBLEM FOR THE LONGER TERM IS POTENTIAL FOR HEAVY RAINFALL ON THE WEEKEND. GFS...DEGEX...ECMWF AND UKMET ALL SUGGEST THAT COLD FRONT AND ASSCTD UPR LVL SHRT WAVE WILL DROP SOUTHEASTWARD FRIDAY AND PUSHES THE CUT-OFF UPR LOW OVR THE UPR OH VLY EASTWARD AGAIN. THIS UPR WAVE AND CUT OFF LOW WILL MELD INTO UPR LVL TROF OVR THE EASTERN U.S BY SAT. THE UPR LVL TROF RUNS INTO A NEARLY STATIONARY UPR LVL RDG OFF THE EAST COAST ON THE WEEKEND. THE FLO WILL REMAIN SWRLY ALOFT OVR THE FRONT IN C NY/NE PA AND AS A RESULT THE FRNT WILL MOVING VERY SLOWLY THRU NY/PA AND BEC STATIONARY SOMEWHERE IN ERN PA TO ERN NY BY SUN AND SUN NGT. IN THE MEANTIME...UPR CONFLUENCE DVLPS TO THE NE AS SHRT WAVE ENERGY GETS CAUGHT UP AND SHEARED OUT TO THE NE. STRG LL MOISTURE ADVECTION IS APPARENT ON THE MODELS INTO A DEFORMATION ZONE N OF THE BNDRY. GFS MODEL SOUNDINGS SHOW TALL AND SKINNY CAPE WITH INSTABILITY ALOFT APPARENT. THE LLJ SEEMS TO BE SUPPLYING THE INSTABILITY THUS MBE VECTORS ARE RELEVANT AND ARE NEAR ZERO AT TIMES SUN AND SUN NGT. NOT SURPRISING SOME OF THE MED RANGE MODELS HINTING AT SIGNFCT RAINS...ON THE ORDER OF 2-3 INCHES. DGEX GOES AS FAR AS 5-6 INCHES. DGEX PROBABLY OVERDONE AND SPREADING CONVECTIVE PRECIP TO A LARGER SCALE. IT HAS BEEN DRY OF LATE...SO IT WILL TAKE A LOT RAIN TO CAUSE ANY MAJOR PROBLEMS. IF WE SEE THIS MAGNITUDE OF RAINFALL (2-3 INCHES)...LOCALIZED FLASH FLOODING WOULD BE THE MAIN CONCERN. RIVERS ARE LOW SO OTHER THAN SOME RISES I DON/T SEE ANY PROBLEMS UNLESS MUCH MORE RAIN FALLS WHICH IS NOT ANTICIPATED. AFTER THIS SYSTEM FINALLY MOVES EAST...HIGH PRESSURE WILL TRY TO BUILD IN. BUT FRONT COULD REMAIN HUNG UP THRU MID- WEEK...THUS SLGHT CHC POPS WILL REMAIN IN GRIDS. && .AVIATION /12Z THURSDAY THROUGH MONDAY/... VFR CONDITIONS SHOULD DOMINATE THE TAF PERIOD. ANY REMAINING MORNING FOG WILL RAPIDLY DISSIPATE THIS HOUR. SCT CU /NEAR 5KFT/ WILL DEVELOP BY MID MORNING. THERE IS AGAIN THE POSSIBILITY OF SOME SHRA ACTIVITY /AND EVEN AN ISOLATED TSRA/...BUT WITH COVERAGE SIMILAR TO YESTERDAY WILL NOT MENTION IN THIS TAF SET. AFTER LIGHT WINDS THIS MORNING...SOUTHWESTERLY WINDS NEAR 10KTS WILL DEVELOP BY MID MORNING...AND DIMINISH AFTER SUNSET THIS EVENING. EXPECT FOG TO DEVELOP IN THE 8-12Z TIMEFRAME TONIGHT WITH AN EVEN MOISTER AIRMASS IN PLACE. FOR THE FRIDAY THROUGH MONDAY TIME PERIOD... EXPECT WIDESPREAD MVFR RESTRICTIONS /EMBEDDED IFR/ BY FRIDAY AFTERNOON WITH SHRA/TSRA. SOME OF THIS ACTIVITY WILL PERSIST OVERNIGHT...BUT SHRA/TSRA COVERAGE WILL DIMINISH. FOG WILL AGAIN CREEP IN BY SATURDAY MORNING. ON SATURDAY...SHRA/TSRA WILL AGAIN BECOME LIKELY...WITH MVFR AND SCATTERED IFR RESTRICTIONS. FOR SUNDAY-MONDAY...IT APPEARS THAT SHRA/TSRA MAY CONTINUE TO CAUSE RESTRICTIONS AT FROM BGM SOUTHEAST TO AVP...WITH VFR CONDITIONS MORE LIKELY AT THE OTHER SITES. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...JMA NEAR TERM...JMA SHORT TERM...JMA LONG TERM...DJN AVIATION...JMA