WOCN31 CWHX 061800 TROPICAL STORM FRANCES INFORMATION STATEMENT ISSUED BY THE CANADIAN HURRICANE CENTRE OF ENVIRONMENT CANADA AT 3.00 PM ADT MONDAY 06 SEPTEMBER 2004. THE NEXT STATEMENT WILL BE ISSUED BY 3.00 AM ADT ON TUESDAY 07 SEPTEMBER 2004. ...FRANCES EXPECTED TO BE POST-TROPICAL BY THE TIME IT REACHES CANADIAN RESPONSE ZONE... 1. CURRENT POSITION, STRENGTH, CENTRAL PRESSURE AND MOTION AT 3.00 PM ADT... TROPICAL STORM FRANCES WAS LOCATED NEAR LATITUDE 30.1 N AND LONGITUDE 84.1 W... ABOUT 20 NAUTICAL MILES OR 40 KM SOUTHEAST OF TALLAHASSEE . MAXIMUM SUSTAINED WINDS ARE ESTIMATED AT 55 KNOTS... 102 KM/H... AND CENTRAL PRESSURE AT 980 MB. FRANCES IS MOVING NORTHWEST AT 8 KNOTS... 15 KM/H. 2. FORECAST POSITION, CENTRAL PRESSURE AND STRENGTH DATE TIME LAT LON MSLP MAX WIND ADT MB KTS KMH SEP 06 3.00 PM 30.1N 84.1W 980 55 102 SEP 07 3.00 AM 31.4N 85.2W 984 30 56 SEP 07 3.00 PM 32.8N 85.5W 990 25 46 SEP 08 3.00 AM 34.3N 85.3W 997 20 37 SEP 08 3.00 PM 36.3N 84.2W 1000 20 37 SEP 09 3.00 AM 39.3N 82.3W 1003 20 37 POST-TROPICAL SEP 09 3.00 PM 43.2N 78.1W 1004 20 37 POST-TROPICAL SEP 10 3.00 AM 47.4N 69.3W 1004 20 37 POST-TROPICAL 3. PUBLIC WEATHER IMPACTS AND WARNINGS SUMMARY MINIMAL TO MODERATE IMPACTS ARE EXPECTED IN EASTERN CANADA LATER THIS WEEK AS FRANCES MAKES ITS WAY INLAND AND FOLLOWS A NORTHEASTWARD TRACK ALONG A LINE SOUTHEAST OF LAKES ERIE AND ONTARIO. REMNANTS OF FRANCES THEN BECOME ABSORBED IN A FRONTAL TROUGH MOVING IN FROM THE WEST THEREAFTER. RAIN...POSSIBLY HEAVY AT TIMES...IS EXPECTED NEAR AND TO THE NORTHWEST OF THE STORM TRACK BRINGING A POTENTIAL FOR HEAVY RAINFALL AMOUNTS OVER EASTERN SECTIONS OF SOUTHERN ONTARIO FOR THURSDAY AND ALONG THE ST. LAWRENCE SEAWAY AREAS OF QUÉBEC FOR FRIDAY. IT IS TOO EARLY TO SAY EXACTLY HOW MUCH RAIN OR EXACTLY WHERE THE RAIN WILL FALL. SPECIAL WEATHER STATEMENTS OR WARNINGS WILL BE ISSUED BY THE REGIONAL STORM PREDICTION CENTRES IF REQUIRED AS THE STORM APPROACHES. 4. MARINE WEATHER IMPACTS AND WARNINGS SUMMARY THE REMNANTS OF FRANCES ARE EXPECTED TO BRING STRONG TO POSSIBLY LOCALLY GALE FORCE WINDS TO THE LOWER GREAT LAKES MARINE WATERS BY THURSDAY. SINCE THE STORM IS EXPECTED TO BE WEAKENING CONSIDERABLY BY THE TIME IT REACHES THE CANADIAN RESPONSE ZONE GALES WILL LIKELY BE MARGINAL IF AT ALL. WARNINGS WILL BE ISSUED BY THE REGIONAL STORM PREDICTION CENTRE IF REQUIRED AS THE STORM APPROACHES. 5. TECHNICAL DISCUSSION FOR METEOROLOGISTS A. ANALYSIS RADAR AND SURFACE OBSERVATIONS GIVE A GOOD ESTIMATE OF CURRENT CENTRAL LOCATION AND PRESSURE. B. PROGNOSTIC AS FRANCES MOVES NORTHWARD IT IS EXPECTED TO ACCELERATE AND RAPIDLY TRANSITION INTO AN EXTRA-TROPICAL STORM SYSTEM WITH A VERY ASSYMETRIC PRECIPITATION PATTERN WITH MINIMAL PRECIPITATION SOUTH OF THE CENTRE. THE RAPID FORWARD SPEED WILL HAVE THE EFFECT OF REDUCING RAINFALL AMOUNTS SOMEWHAT ALTHOUGH LOCAL AMOUNTS IN THE 50 TO 80 MM RANGE ARE STILL POSSIBLE. THE OMEGA FIELD OF THE GFS AND THE GFS VORT PATTERN IS SLOWER THAN OUR TRACK. THE GFS VORT PATTERN RAPIDLY OUTSTRIPS THE QPF PATTERN INDICATING IT IS NOT HANDLING THE SITUATION AS WELL AS IT COULD. GFDL CONSIDERABLY SLOWER THAN OTHER MODELS. THE CANADIAN GLOBAL MODEL TRACKS THE VORTICITY SIGNATURE OVER EXTREME EASTERN SECTIONS OF LAKE ERIE BY THURSDAY MORNING THEN IT BECOMES RAPIDLY SWEPT UP BY THE STRONG SOUTHWESTERLY FLOW OF THE POSITIVELY-TILTED UPPER TROUGH. THE FLOW SWEEPS THE VORTICITY SIGNATURE RAPIDLY UP THE ST. LAWRENCE VALLEY. THE VORTICITY SIGNATURE DEGRADES RAPIDLY THEREAFTER. THE SYSTEM BY THIS POINT IS EXPECTED TO BECOME COMPLETELY ABSORBED BY THE STRONG BAROCLINIC ZONE. OUR TRACK FOLLOWS NHC TRACK CLOSELY UNTIL THE CANADIAN RESPONSE ZONE THEN MOVES A BIT FASTER THAN NHC AS WE TRACK FOLLOWING THE GLOBAL MODEL VORT SIGNATURE. NO GUIDANCE REFLECTION REMAINS RECOGNIZABLE AS IT PASSES INTO THE GULF OF ST. LAWRENCE. DUE TO THE EXTRA-TROPICAL NATURE OF THIS SYSTEM AND THE FACT THAT THE CANADIAN MODELS CURRENTLY SEEM TO BE HANDLING THE PRECIPITATION CONSIDERATIONS WELL CHC WILL ONLY BE MESSAGING EVERY 12 HOURS UNLESS CHANGES ARE REQUIRED. C. PUBLIC WEATHER FRANCES IS EXPECTED TO TRANSITION INTO A BAROCLINIC LOW TRACKING THROUGH THE STATE OF NEW YORK ON THURSDAY AND THEN UP THE ST. LAWRENCE VALLEY BY FRIDAY. AS WITH ANY POST-TROPICAL SYSTEM IT IS DIFFICULT TO PREDICT THE AMOUNT OF RAINFALL. THE CANADIAN GLOBAL HAS MAINTAINED A FAIRLY CONSISTENT AND STABLE FORECAST PATTERN ASSOCIATED WITH THE POTENTIAL REMNANTS OF FRANCES...AND THE PRECIPITATION BULLSEYE IS EXPECTED TO REMAIN SOUTHEAST OF TORONTO AND BEGIN TO DIMINSH SOMEWHAT BY THE TIME IT REACHES QUÉBEC. THE QPF GRADIENT EDGE IS EXPECTED TO BE QUITE SHARP KEEPING THE HEAVIEST PRECIPITATION MOSTLY OVER OFFSHORE WATERS OF THE NORTHERN EDGES OF LAKE ONTARIO AND EASTERN LAKE ERIE. CURRENT INDICATIONS ARE THAT SOMETHING IN THE 50 TO 80 MM RANGE IS POSSIBLE NEAR AND NORTHWEST OF THE TRACK. THE MOISTURE PATTERN WILL HAVE TO BE MONITORED CLOSELY. THE RAIN IS EXPECTED TO MOVE INTO EXTREME SOUTHEASTERN AREAS OF ONTARIO THURSDAY. ANY SPECIAL WEATHER STATEMENTS OR WARNINGS WILL BE HANDLED IN THE REGULAR FORECAST PRODUCTS BY THE REGIONAL STORM PREDICTION CENTRES IF REQUIRED AS THE STORM APPROACHES. D. MARINE WEATHER THE REMNANTS OF FRANCES ARE EXPECTED TO BRING STRONG TO POSSIBLE LOCAL GALE FORCE WINDS TO THE EASTERN PARTS OF LAKE ERIE AND ACROSS LAKE ONTARIO MARINE WATERS BY THURSDAY. SINCE THE STORM IS EXPECTED TO BE WEAKENING CONSIDERABLY BY TIME IT REACHES THE CANADIAN RESPONSE ZONE GALES WILL LIKELY BE MARGINAL IF AT ALL. WARNINGS WILL BE ISSUED BY THE REGIONAL STORM PREDICTION CENTRE IF REQUIRED AS THE STORM APPROACHES. END MARSHALL