| Movement is now officially NW. Lee is forecast to grow in size and I really hope people pay attention to that rather than the fact that the wind speeds will be coming down. This is going to be a very large storm. A lot of things refer to that large wind field increase, that has happened and will. You can read the discussion below, but here is where they talk about it: "Note- The 34- and 50-kt wind speed probabilities beyond 36 hours in the text product and graphics are likely underestimating the risk of those winds occurring. This is because the forecast wind field of Lee is considerably larger than average compared to the wind field used to derive the wind speed probability product." "The big change in the aircraft data was the sizable expansion of the whole wind field in the eastern semicircle of the hurricane, which was also shown by a late-arriving SAR pass this morning." "Even though the core of Lee is expected to be well west of Bermuda, Lee's large wind field could arrive early Thursday on the island." "It remains too soon to know what level of additional impacts Lee might have along the northeastern U.S. coast and Atlantic Canada late this week and this weekend. However, since wind and rainfall hazards will extend well away from the center as Lee grows in size, users should continue to monitor updates to Lee's forecast during the next several days." Rainfall could also be a big issue in the Northeast U.S. and into Canada, regardless of the exact track. Quantitative Precipitation Forecasts from Weather Prediction Center: https://www.wpc.ncep.noaa.gov/index.shtml#page=qpf If it makes landfall west of the Bay of Fundy, I do wonder what the surge would be there. They have a lot of variability in the tides there, from low to hide. I also wonder about the surge along the north side of Cape Cod and in that area, with winds from the north, if the storm does pass east of there, whether close or further. I'm not familiar with the area and don't know how much surge might be expected. But the water would be pushed into Cape Cod Bay if it passes east of there. Track: https://www.nhc.noaa.gov/refresh/graphics_at3+shtml/?cone#contents Satellite floaters: https://www.star.nesdis.noaa.gov/GOES/floater.php?stormid=AL132023 https://rammb-data.cira.colostate.edu/tc_realtime/storm.asp?storm_identifier=al132023 Carib view: https://www.star.nesdis.noaa.gov/GOES/sector_band.php?sat=G16§or=car&band=13&length=24 Later it will be more on the U.S. East Coast satellite view: https://www.star.nesdis.noaa.gov/GOES/sector_band.php?sat=G16§or=eus&band=13&length=12 SLIDER display from Colorado State: https://rammb-slider.cira.colostate.edu/?sat=goes-16&sec=full_disk&x=11304&y=4264&z=2&angle=0&im=12&ts=1&st=0&et=0&speed=130&motion=loop&maps%5Bborders%5D=white&p%5B0%5D=band_13&opacity%5B0%5D=1&pause=0&slider=-1&hide_controls=0&mouse_draw=0&follow_feature=0&follow_hide=0&s=rammb-slider&draw_color=FFD700&draw_width=6 Hurricane Lee Discussion Number 30 NWS National Hurricane Center Miami FL AL132023 Issued by the NWS Weather Prediction Center College Park MD 500 PM AST Tue Sep 12 2023 GOES-East satellite and information from an Air Force Reserve Hurricane Hunter plane indicate a slight recent improvement in the inner-eye structure with a 5-mb pressure fall noted in the most recent pass. However, peak 700-mb flight-level winds were lower than 6 hr ago with SFMR estimates about the same. Given the mixed signals, we will maintain the initial wind speed at 100 kts for this advisory. The big change in the aircraft data was the sizable expansion of the whole wind field in the eastern semicircle of the hurricane, which was also shown by a late-arriving SAR pass this morning. Lee has turned northwestward (315/6 kt) as the mid-level ridging continues to its north and east. A digging eastern United States trough remains on track to weaken the ridge during the next few days. Lee is expected to turn more northward and accelerate by Thursday as a result of this pattern change. Even though the core of Lee is expected to be well west of Bermuda, Lee's large wind field could arrive early Thursday on the island. After day 3, there is an increase in guidance spread as the hurricane interacts with an approaching frontal zone, which could cause a small leftward bend in the track. However, recent guidance has tightened somewhat, and the official forecast follows a middle-ground solution similar to the GEFS/ECMWF ensemble means, on the fast side of the consensus. The hurricane is expected to gradually weaken over the next few days while it moves over cooler waters into a higher-shear environment. Still, all of the guidance keep this system quite large and at hurricane-strength for the next few days. Once the circulation reaches the colder water north of the Gulf Stream, more significant weakening is expected at the day 4-5 period as it quickly transitions to an extratropical low. Little change was made to the previous forecast, which is also close to the consensus aids, and the forward speed north of the Gulf Stream will be important in the exact wind speed as Lee approaches the mainland. Note- The 34- and 50-kt wind speed probabilities beyond 36 hours in the text product and graphics are likely underestimating the risk of those winds occurring. This is because the forecast wind field of Lee is considerably larger than average compared to the wind field used to derive the wind speed probability product. KEY MESSAGES: 1. Dangerous surf and life-threatening rip currents will affect portions of the northern Leeward Islands, the Virgin Islands, Puerto Rico, Hispaniola, the Turks and Caicos Islands, the Bahamas, Bermuda, and most of the U.S East Coast through much of the week. 2. There is an increasing risk of strong winds, rainfall, and high surf impacts to Bermuda later this week, and a Tropical Storm Watch remains in effect for the island. 3. It remains too soon to know what level of additional impacts Lee might have along the northeastern U.S. coast and Atlantic Canada late this week and this weekend. However, since wind and rainfall hazards will extend well away from the center as Lee grows in size, users should continue to monitor updates to Lee's forecast during the next several days. FORECAST POSITIONS AND MAX WINDS INIT 12/2100Z 24.7N 66.4W 100 KT 115 MPH 12H 13/0600Z 25.4N 67.0W 100 KT 115 MPH 24H 13/1800Z 26.7N 67.6W 95 KT 110 MPH 36H 14/0600Z 28.6N 68.1W 90 KT 105 MPH 48H 14/1800Z 30.7N 68.2W 85 KT 100 MPH 60H 15/0600Z 33.4N 67.6W 80 KT 90 MPH 72H 15/1800Z 36.4N 66.8W 75 KT 85 MPH 96H 16/1800Z 42.8N 66.5W 65 KT 75 MPH 120H 17/1800Z 47.1N 64.5W 40 KT 45 MPH...POST-TROP/EXTRATROP $$ Forecaster Gallina/Blake/Bann Hurricane Lee Intermediate Advisory Number 29A NWS National Hurricane Center Miami FL AL132023 Issued by the NWS Weather Prediction Center College Park MD 200 PM AST Tue Sep 12 2023 ...AIR FORCE HURRICANE HUNTER CURRENTLY INVESTIGATING LEE... ...HAZARDOUS SURF AND RIP CURRENT CONDITIONS EXPECTED AT BEACHES ACROSS THE WESTERN ATLANTIC ALL WEEK... SUMMARY OF 200 PM AST...1800 UTC...INFORMATION ---------------------------------------------- LOCATION...24.5N 66.2W ABOUT 545 MI...875 KM S OF BERMUDA MAXIMUM SUSTAINED WINDS...115 MPH...185 KM/H PRESENT MOVEMENT...WNW OR 300 DEGREES AT 6 MPH...9 KM/H MINIMUM CENTRAL PRESSURE...951 MB...28.09 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: None. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Tropical Storm Watch is in effect for... * Bermuda A Tropical Storm Watch means that tropical storm conditions are possible within the watch area, generally within 48 hours. Interests in the northeastern United States and Atlantic Canada should monitor the progress of Lee. For storm information specific to your area, please monitor products issued by your national meteorological service. DISCUSSION AND OUTLOOK ---------------------- At 200 PM AST (1800 UTC), the center of Hurricane Lee was located near latitude 24.5 North, longitude 66.2 West. Lee is moving toward the west-northwest near 6 mph (9 km/h). A slow west-northwest to northwest motion is expected during the next day or two, followed by a turn toward the north by midweek. On the forecast track, Lee is expected to pass near but to the west of Bermuda in a few days. Air Force Reserve Hurricane Hunter data indicate that the maximum sustained winds remain near 115 mph (185 km/h) with higher gusts. Lee is a category 3 hurricane on the Saffir-Simpson Hurricane Wind Scale. Some slow weakening is forecast during the next 48 hours, but Lee is expected to remain a large and powerful hurricane. Hurricane-force winds extend outward up to 90 miles (150 km) from the center and tropical-storm-force winds extend outward up to 205 miles (335 km). The estimated minimum central pressure is 951 mb (28.09 inches). HAZARDS AFFECTING LAND ---------------------- Key messages for Lee can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDAT3 and WMO header WTNT43 KNHC and on the web at hurricanes.gov/text/MIATCDAT3.shtml WIND: Tropical storm force winds are possible on Bermuda starting Thursday morning. SURF: Swells generated by Lee are affecting portions of the Lesser Antilles, the British and U.S. Virgin Islands, Puerto Rico, Hispaniola, the Turks and Caicos Islands, the Bahamas, and Bermuda. These swells are likely to cause life-threatening surf and rip current conditions. Dangerous surf and rip currents are affecting portions of the southeastern U.S. coast, and these conditions are forecast to spread northward along much of the U.S. East Coast during the next couple of days. Please consult products from your local weather office. RAIN: Outer rain bands from Lee may produce rainfall amounts of 1 to 2 inches, 25 to 50 millimeters, across Bermuda Thursday into early Friday. NEXT ADVISORY ------------- Next complete advisory at 500 PM AST. $$ Forecaster Gallina/Blake/Bann GFS: https://www.tropicaltidbits.com/analysis/models/?model=gfs®ion=eus&pkg=mslp_pcpn Euro: https://www.tropicaltidbits.com/analysis/models/?model=ecmwf®ion=eus&pkg=mslp_pcpn GFS Ensemble: https://www.tropicaltidbits.com/analysis/models/?model=gfs-ens®ion=eus&pkg=lowlocs Euro Ensemble: https://www.tropicaltidbits.com/analysis/models/?model=eps®ion=eus&pkg=lowlocs Storm specific models: https://hurricanecity.com/models/models.cgi?basin=al&year=2023&storm=13 Recon: https://hurricanecity.com/recon/ |