| We have the first instance of a potential tropical cyclone that did not become a depression or higher. If 93L develops, it's number will be 11L. If it develops first as a depression, it would be Tropical Depression Eleven. Next name on the list is Irma. What was Potential Tropical Cyclone Ten is forecast to strengthen, but it's becoming extratropical so the NHC has ended advisories. Final NHC track: http://www.nhc.noaa.gov/refresh/graphics_at5+shtml/?cone#contents Floater: http://www.ssd.noaa.gov/PS/TROP/floaters/10L/10L_floater.html Atlantic imagery: http://www.ssd.noaa.gov/PS/TROP/trop-atl.html Potential Tropical Cyclone Ten Discussion Number 9 NWS National Hurricane Center Miami FL AL102017 500 PM EDT Tue Aug 29 2017 Visible satellite images indicate that a more well-defined circulation has begun to form east of the Outer Banks, and surface observations indicate that pressures are falling. The low is becoming extratropical, and there is no longer a possibility of it becoming a tropical cyclone. In addition, the associated tropical-storm-force winds that have been occurring to the southeast of the center are limited to marine areas, so this will be the last NHC advisory on this system. Maximum winds are estimated to be 40 kt to the southeast of the center. Baroclinic influences are expected to cause the low to deepen as an extratropical cyclone during the next day or two, and it is forecast to produce sustained hurricane-force winds over the northwestern Atlantic by late Wednesday. Gradual weakening is forecast after 36 hours, and the cyclone is likely to be absorbed by another extratropical system over the north Atlantic by day 5. The low continues to accelerate toward the northeast with an initial motion of 050/21 kt, and it should move even faster toward the northeast or east-northeast across the north Atlantic through day 4, embedded in the mid-latitude westerlies. The track, intensity, and wind radii forecasts incorporate guidance provided by NOAA's Ocean Prediction Center. Strong winds on the northern and western side of a frontal boundary associated with the low are expected to affect portions of the mid-Atlantic coast. As a result, high wind warnings are in effect for coastal sections of northeastern North Carolina, southeastern Virginia, and the eastern shore of Virginia and Maryland through this evening. This is the last advisory issued by NHC, and additional information on this system can be found in High Seas Forecasts issued by the National Weather Service, under AWIPS header NFDHSFAT1, WMO header FZNT01 KWBC, and available on the Web at http://www.opc.ncep.noaa.gov/shtml/NFDHSFAT1.shtml. FORECAST POSITIONS AND MAX WINDS INIT 29/2100Z 36.0N 74.3W 40 KT 45 MPH 12H 30/0600Z 37.6N 70.7W 45 KT 50 MPH...POST-TROP/EXTRATROP 24H 30/1800Z 39.3N 65.6W 60 KT 70 MPH...POST-TROP/EXTRATROP 36H 31/0600Z 40.9N 60.0W 70 KT 80 MPH...POST-TROP/EXTRATROP 48H 31/1800Z 42.8N 54.5W 55 KT 65 MPH...POST-TROP/EXTRATROP 72H 01/1800Z 47.4N 41.3W 45 KT 50 MPH...POST-TROP/EXTRATROP 96H 02/1800Z 52.0N 25.5W 35 KT 40 MPH...POST-TROP/EXTRATROP 120H 03/1800Z...ABSORBED $$ Forecaster Berg Potential Tropical Cyclone Ten Advisory Number 9 NWS National Hurricane Center Miami FL AL102017 500 PM EDT Tue Aug 29 2017 ...DISTURBANCE MOVING AWAY FROM THE NORTH CAROLINA COAST... ...THIS IS THE LAST ADVISORY... SUMMARY OF 500 PM EDT...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...36.0N 74.3W ABOUT 85 MI...140 KM NE OF CAPE HATTERAS NORTH CAROLINA MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H PRESENT MOVEMENT...NE OR 50 DEGREES AT 24 MPH...39 KM/H MINIMUM CENTRAL PRESSURE...1003 MB...29.62 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: All tropical storm warnings for the coast of North Carolina have been discontinued. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: There are no coastal tropical watches or warnings in effect. High wind warnings are in effect for coastal portions of northeastern North Carolina, southeastern Virginia, and the eastern shore of Virginia and Maryland through this evening. For storm information specific to your area, including possible inland watches and warnings, please monitor products issued by your local National Weather Service forecast office. DISCUSSION AND 48-HOUR OUTLOOK ------------------------------ At 500 PM EDT (2100 UTC), the disturbance was centered off the coast of North Carolina near latitude 36.0 North, longitude 74.3 West. The system is moving toward the northeast near 20 mph (31 km/h), and it is expected to accelerate further toward the northeast and east-northeast during the next couple of days. The disturbance will continue to move away from the North Carolina coast over the western Atlantic Ocean tonight. Maximum sustained winds are near 45 mph (75 km/h) with higher gusts. The disturbance is forecast to strengthen at sea and become a hurricane-force extratropical low over the northwestern Atlantic Ocean by Wednesday evening. The system is not expected to become a tropical cyclone. * Formation chance through 48 hours...low...near 0 percent * Formation chance through 5 days...low...near 0 percent Tropical-storm-force winds extend outward up to 105 miles (165 km) to the east of the center. The estimated minimum central pressure is 1003 mb (29.62 inches). HAZARDS AFFECTING LAND ---------------------- WIND: Strong winds, with gusts up to 55 mph, are expected across coastal portions of northeastern North Carolina, southeastern Virginia, and the eastern shore of Virginia and Maryland through this evening. RAINFALL: The system is expected to produce total rain accumulations of 1 to 3 inches from the southeast Virginia coast into the Delmarva through Wednesday. The heavier rains may result in some flooding concerns along coastal areas. SURF: Swells generated by this disturbance will affect portions of the North Carolina and Virginia coasts during the next day or so, creating dangerous surf and rip current conditions. Please consult products from your local weather office. NEXT ADVISORY ------------- This is the last public advisory issued by the National Hurricane Center on this system. Additional information on this system can be found in High Seas Forecasts issued by the National Weather Service, under AWIPS header NFDHSFAT1, WMO header FZNT01 KWBC, and available on the Web at http://www.opc.ncep.noaa.gov/shtml/NFDHSFAT1.shtml. $$ Forecaster Berg |