5pm AST Sunday (Sep. 10th) on Lee: 120mph; 954mb; WNW at 8mph
Posted by Chris in Tampa on 9/10/2023, 5:16 pm
| 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 Colorado State SLIDER display: https://rammb-slider.cira.colostate.edu/?sat=goes-16&sec=full_disk&x=11752&y=5248&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 22 NWS National Hurricane Center Miami FL AL132023 500 PM AST Sun Sep 10 2023 Lee has continued to become better organized today. The eye has become more apparent in both infrared and visible satellite imagery this afternoon, and reconnaissance aircraft reports indicate that the eye has contracted today. An Air Force Reserve Hurricane Hunter aircraft that is currently investigating Lee has measured peak 700-mb flight-level winds of 112 kt and SFMR winds of 106 kt. Near the conclusion of the earlier NOAA P-3 aircraft mission an eyewall dropsonde measured mean boundary layer winds in the lowest 150 m of the sonde of 117 kt, which supported surface winds of around 100 kt. Based on the improved satellite presentation and the recent SFMR wind report, Lee's initial intensity has been raised to 105 kt. As mentioned this morning, the vertical wind shear over Lee appears to have decreased as the upper-level outflow has become better established over the southern and southwestern portions of the storm. Some further reduction in shear is anticipated during the next day or so, and Lee is expected to restrengthen during that time. The NHC intensity prediction calls for steady intensification during the next 24 hours or so, and Lee is forecast regain category 4 status tonight or early Monday. After that time, the slow motion of the hurricane could cause the water beneath the hurricane to cool due to upwelling, which is likely to cause Lee's intensity to plateau or weaken slight during the middle portion of the forecast period. By days 4 and 5, increasing southwesterly shear is likely to cause weakening, however Lee's wind field is expected to expand by that time, and Lee is forecast to remain a strong hurricane through most of this week. Lee is moving west-northwestward or 300 at 7 kt. Lee's is expected to move slowly northwestward during the next couple of days as its forward progress is impeded by a high pressure ridge located to the northwest of the storm. By Wednesday, a mid-latitude trough moving across the Great Lakes region and into the northeastern United States should weaken the ridge and allow Lee to turn northward. The ECMWF model has trended faster with the northward progression of Lee late in the period and there is a little less spread in the guidance at day 5. The updated NHC track forecast is very similar the previous track, but has trended a bit faster later in the period. Users should be reminded to not focus on the exact forecast track, especially at the longer range, as the average day 4 and 5 track errors are about 145 and 200 miles, respectively. 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, and Bermuda through much of this week. 2. Lee could bring wind, rainfall, and high surf impacts to Bermuda later this week. Although it is too soon to determine the specific timing and level of those impacts, interests on Bermuda should monitor the latest forecasts for Lee. 3. It remains too soon to know what level of impacts, if any, Lee might have along the U.S. East Coast and Atlantic Canada late this week, especially since the hurricane is expected to slow down considerably over the southwestern Atlantic. Regardless, dangerous surf and rip currents are expected along most of the U.S. East Coast this week as Lee grows in size. Users should continue to monitor updates to the forecast of Lee during the next several days. FORECAST POSITIONS AND MAX WINDS INIT 10/2100Z 22.1N 61.7W 105 KT 120 MPH 12H 11/0600Z 22.7N 62.7W 115 KT 130 MPH 24H 11/1800Z 23.3N 63.9W 120 KT 140 MPH 36H 12/0600Z 23.8N 65.1W 120 KT 140 MPH 48H 12/1800Z 24.2N 66.2W 115 KT 130 MPH 60H 13/0600Z 24.7N 67.0W 105 KT 120 MPH 72H 13/1800Z 25.6N 67.6W 100 KT 115 MPH 96H 14/1800Z 28.9N 68.0W 90 KT 105 MPH 120H 15/1800Z 33.6N 67.4W 80 KT 90 MPH $$ Forecaster Brown The forecast peak is back up to 140mph, with it weakening a lot, in terms of the wind speed, after that. It remains too early to know where any landfalls might possibly be, from Bermuda, the U.S. Northeast and/or the Atlantic coast of Canada. Global models: GFS: https://www.tropicaltidbits.com/analysis/models/?model=gfs®ion=atl&pkg=mslp_pcpn Euro: https://www.tropicaltidbits.com/analysis/models/?model=ecmwf®ion=atl&pkg=mslp_pcpn Here is a closer view of the U.S. East Coast: 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 I also like to look at the ensembles. Here they are with that same U.S. East Coast view: GFS: https://www.tropicaltidbits.com/analysis/models/?model=gfs-ens®ion=eus&pkg=lowlocs Euro: https://www.tropicaltidbits.com/analysis/models/?model=eps®ion=eus&pkg=lowlocs The NOAA G-IV is up dropping sondes from the plane, sampling the upper air environment around and ahead of the storm. That data will get into some of the models later into the evening and overnight. They'll be doing more of those missions, so that should improve some of the model forecasts some. NOAA G-IV through 5:00pm AST Sunday:  Recon: https://hurricanecity.com/recon/ P-3 mission on the way to the storm. (not pictured) |
1
In this thread:
- Tropical Atlantic Marine Weather Briefing - September 10, 2023 - cypresstx, 9/10/2023, 5:35 pm
Post A Reply