| Track and watches and warnings graphically: https://www.nhc.noaa.gov/refresh/graphics_at4+shtml/?cone#contents Dynamic map: https://www.nhc.noaa.gov/refresh/graphics_at4+shtml/?gm_track#contents Satellite floater: https://www.star.nesdis.noaa.gov/GOES/floater.php?stormid=AL092021 Mesoscale floaters: https://www.star.nesdis.noaa.gov/GOES/meso_index.php https://weather.cod.edu/satrad/?parms=meso-meso1-13-24-0-100-1&checked=map&colorbar=data More satellite data: http://hurricanecity.com/models/models.cgi?basin=al&year=2021&storm=09#satellite Cuba radars: http://www.insmet.cu/asp/genesis.asp?TB0=PLANTILLAS&TB1=RADARES Key West radar: https://mrms.nssl.noaa.gov/qvs/product_viewer/index.php?time_mode=update&zoom=7&clon=-81&clat=23&base=0&overlays=1&mping_mode=0&product_type=crefls&product=CREF&qpe_pal_option=0&opacity=1&looping_active=on&num_frames=18&frame_step=200&seconds_step=600 Long loops for Cuba radars on Brian McNoldy's page: http://bmcnoldy.rsmas.miami.edu/tropics/radar/ Hurricane Ida Discussion Number 6 NWS National Hurricane Center Miami FL AL092021 500 PM EDT Fri Aug 27 2021 Cuban radar data and reports from an earlier Air Force Reserve Hurricane Hunter mission indicate that Ida's inner core structure continued to improve after the release of the previous advisory package. An eye became apparent in radar imagery before the center reached the Isle of Youth, and the final fix from the Air Force Hurricane Hunter aircraft reported a closed 24-n-mi wide eye. The aircraft measured winds to support hurricane intensity shortly before 1800 UTC, and during the final northeast eyewall pass, and flight-level wind data support increasing the intensity to 70 kt, which is used as the initial intensity for this advisory. The upper-level outflow has expanded over all but the southwestern portion of the circulation, and the upper-level wind pattern is forecast to continue to improve overnight and early Saturday. Once Ida moves past western Cuba and into the southeastern Gulf of Mexico, it will be moving through a very favorable oceanic and atmospheric environment consisting of high ocean heat content waters, low vertical wind shear, and a moist low- to mid-level atmosphere. These conditions are likely to result in a period of rapid strengthening during the next 24 to 36 hours. In fact, with the higher initial wind speed, the intensity guidance has significantly increased this cycle, and the bulk of the guidance now brings Ida to category 4 intensity. The NHC forecast explicitly calls for rapid intensification during the next 24 to 36 hours, which is supported by several of the dynamical models, the LGEM model, and high probabilities of rapid intensification indicated by the SHIPS and DTOPS RI guidance. The NHC forecast is near the IVCN multi-model consensus aid, but is lower than HCCA and LGEM. It should be noted that some fluctuations in intensity are possible as Ida nears the northern Gulf coast due to possible eyewall replacement cycles. In addition to the expected increase in strength, the dynamical model guidance again calls for Ida's wind field to expand while it moves over the Gulf of Mexico. As a result, there is higher-than-normal confidence that a large and powerful hurricane will impact portions of the northern Gulf coast by late this weekend and early next week. Ida has wobbled a little right of the previous track, but the longer term motion continues to be northwestward or 320/13 kt. The steering currents remain well-established as a strong deep-layer ridge over the western Atlantic should continue to steer Ida northwestward across the Gulf this weekend. Ida will approach the western portion of the ridge after landfall, and this should result in a slower northward motion by day 3. After that time, a short-wave trough over the central United States is expected to cause the system to turn northeastward. The track guidance remains in remarkably good agreement through landfall along the northern Gulf coast, and there is higher-than-normal confidence in that portion of the track forecast. However, users are again reminded to not focus on the exact details of the track forecast as storm surge, wind, and rainfall impacts will extend far from the center. Key Messages: 1. Life-threatening storm surge and hurricane conditions are expected to continue through tonight in portions of western Cuba, including the Isle of Youth, where a Hurricane Warning is in effect. Life-threatening heavy rains, flash flooding and mudslides are expected across Jamaica, the Cayman Islands, and western Cuba, including the Isle of Youth. 2. There is a danger of life-threatening storm surge inundation Sunday along the coasts of Louisiana and Mississippi within the Storm Surge Warning area. Extremely life-threatening inundation of 10 to 15 feet above ground level is possible within the area from Morgan City, Louisiana, to the Mouth of the Mississippi River. Interests throughout the warning area should follow any advice given by local officials. 3. Ida is expected to be an extremely dangerous major hurricane when it reaches the coast of Louisiana. Hurricane-force winds are expected Sunday in portions of the Hurricane Warning area along the Louisiana coast, including metropolitan New Orleans, with potentially catastrophic wind damage possible where the core of Ida moves onshore. Actions to protect life and property should be rushed to completion in the warning area. 4. Ida is likely to produce heavy rainfall later Sunday into Monday across the central Gulf Coast from southeast Louisiana to coastal Mississippi and Alabama, resulting in considerable flash, urban, small stream, and riverine flooding impacts. As Ida moves inland, flooding impacts are possible across portions of the Lower Mississippi and Tennessee Valleys. FORECAST POSITIONS AND MAX WINDS INIT 27/2100Z 22.1N 83.2W 70 KT 80 MPH 12H 28/0600Z 23.5N 84.8W 85 KT 100 MPH 24H 28/1800Z 25.3N 86.9W 105 KT 120 MPH 36H 29/0600Z 27.1N 89.0W 115 KT 130 MPH 48H 29/1800Z 28.6N 90.6W 120 KT 140 MPH 60H 30/0600Z 30.0N 91.3W 80 KT 90 MPH...INLAND 72H 30/1800Z 31.5N 91.1W 40 KT 45 MPH...INLAND 96H 31/1800Z 34.4N 89.3W 30 KT 35 MPH...INLAND 120H 01/1800Z 36.0N 86.0W 20 KT 25 MPH...POST-TROP/REMNT LOW $$ Forecaster Brown Hurricane Ida Advisory Number 6...Corrected NWS National Hurricane Center Miami FL AL092021 500 PM EDT Fri Aug 27 2021 Corrected typo in the second headline ...CENTER OF IDA APPROACHING WESTERN CUBA... ...STORM SURGE AND HURRICANE WARNINGS ISSUED FOR PORTIONS OF THE NORTHERN GULF COAST... SUMMARY OF 500 PM EDT...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...22.1N 83.2W ABOUT 45 MI...70 KM NW OF THE ISLE OF YOUTH ABOUT 90 MI...145 KM SW OF HAVANA CUBA MAXIMUM SUSTAINED WINDS...80 MPH...130 KM/H PRESENT MOVEMENT...NW OR 320 DEGREES AT 15 MPH...24 KM/H MINIMUM CENTRAL PRESSURE...985 MB...29.09 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: A Storm Surge Warning has been issued from east of Rockefeller Wildlife Refuge, Louisiana, to the Mississippi/Alabama border including Vermilion Bay, Lake Borgne, Lake Pontchartrain, and Lake Maurepas. A Hurricane Warning has been issued for the coast of Louisiana from Intracoastal City to the Mouth of the Pearl River, including Lake Pontchartrain, Lake Maurepas, and Metropolitan New Orleans. A Tropical Storm Warning has been issued for the northern Gulf coast from the Mouth of the Pearl River to the Mississippi/Alabama border. A Tropical Storm Warning has also been issued for the coast of Louisiana from west of Intracoastal City to Cameron. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Storm Surge Warning is in effect for... * East of Rockefeller Wildlife Refuge Louisiana to the Mississippi/Alabama border * Vermilion Bay, Lake Borgne, Lake Pontchartrain, and Lake Maurepas A Hurricane Warning is in effect for... * Cuban provinces of Pinar del Rio and Artemisa, and the Isle of Youth * Intracoastal City Louisiana to the Mouth of the Pearl River * Lake Pontchartrain, Lake Maurepas, and Metropolitan New Orleans A Storm Surge Watch is in effect for... * Sabine Pass to Rockefeller Wildlife Refuge Louisiana * Mobile Bay A Hurricane Watch is in effect for... * Cameron Louisiana to west of Intracoastal City Louisiana * Mouth of the Pearl River to the Mississippi/Alabama border A Tropical Storm Warning is in effect for... * Cuban provinces of Matanzas, Mayabeque, and Havana * Cameron Louisiana to west of Intracoastal City Louisiana * Mouth of the Pearl River to the Mississippi/Alabama border A Tropical Storm Watch is in effect for... * Mississippi/Alabama border to the Alabama/Florida border A Storm Surge Warning means there is a danger of life-threatening inundation, from rising water moving inland from the coastline, during the next 36 hours in the indicated locations. For a depiction of areas at risk, please see the National Weather Service Storm Surge Watch/Warning Graphic, available at hurricanes.gov. This is a life-threatening situation. Persons located within these areas should take all necessary actions to protect life and property from rising water and the potential for other dangerous conditions. Promptly follow evacuation and other instructions from local officials. A Hurricane Warning means that hurricane conditions are expected somewhere within the warning area. A warning is typically issued 36 hours before the anticipated first occurrence of tropical-storm-force winds, conditions that make outside preparations difficult or dangerous. Preparations to protect life and property should be rushed to completion. A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area within 36 hours. A Storm Surge Watch means there is a possibility of life- threatening inundation, from rising water moving inland from the coastline, in the indicated locations during the next 48 hours. A Hurricane Watch means that hurricane conditions are possible within the watch area. A watch is typically issued 48 hours before the anticipated first occurrence of tropical-storm-force winds, conditions that make outside preparations difficult or dangerous. A Tropical Storm Watch means that tropical storm conditions are possible within the watch area, generally within 48 hours. Interests elsewhere along the northern U.S. Gulf coast should monitor the progress of this system. Interests in the Dry Tortugas should also monitor the progress of Ida. For storm information specific to your area in the United States, including possible inland watches and warnings, please monitor products issued by your local National Weather Service forecast office. For storm information specific to your area outside of the United States, please monitor products issued by your national meteorological service. DISCUSSION AND OUTLOOK ---------------------- At 500 PM EDT (2100 UTC), the center of Hurricane Ida was located near latitude 22.1 North, longitude 83.2 West. Ida is moving toward the northwest near 15 mph (24 km/h), and this general motion should continue until Ida reaches the northern Gulf coast on Sunday. A slower northward motion is forecast after Ida reaches the northern Gulf coast. On the forecast track, the center of Ida will pass over western Cuba during the next several hours, and then move over the southeastern and central Gulf of Mexico later tonight and Saturday. Ida is forecast to make landfall along the U.S. northern Gulf coast within the hurricane warning area on Sunday. Maximum sustained winds have increased to near 80 mph (130 km/h) with higher gusts. Little change in strength is anticipated while Ida moves over western Cuba this evening. Steady to rapid strengthening is expected when Ida moves over the southeastern and central Gulf of Mexico over the weekend, and Ida is expected to be an extremely dangerous major hurricane when it approaches the northern Gulf coast on Sunday. Hurricane-force winds extend outward up to 25 miles (35 km) from the center and tropical-storm-force winds extend outward up to 90 miles (150 km). A wind gust to 46 mph (74 km/h) has recently been reported on Cayo Largo, Cuba. The estimated minimum central pressure is 985 mb (29.09 inches). HAZARDS AFFECTING LAND ---------------------- Key messages for Ida can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDAT4, WMO header WTNT44 KNHC, and on the web at hurricanes.gov/graphics_at4.shtml?key_messages. STORM SURGE: A dangerous storm surge will raise water levels by as much as 4 to 6 feet above normal tide levels in areas of onshore winds along the immediate coast of the Isle of Youth and near and to the east of where the center crosses the coast of western Cuba. Near the coast, the surge will be accompanied by large and destructive waves. The combination of a dangerous storm surge and the tide will cause normally dry areas near the coast to be flooded by rising waters moving inland from the shoreline. The water could reach the following heights above ground somewhere in the indicated areas if the peak surge occurs at the time of high tide... Morgan City, LA to Mouth of the Mississippi River...10-15 ft Mouth of the Mississippi River to Ocean Springs, MS including Lake Borgne...7-11 ft Intracoastal City, LA to Morgan City, LA including Vermilion Bay...6-9 ft Ocean Springs, MS to MS/AL border...4-7 ft Lake Pontchartrain...4-7 ft Lake Maurepas...3-5 ft Pecan Island, LA to Intracoastal City, LA...3-5 ft MS/AL border to AL/FL border including Mobile Bay...2-4 ft Sabine Pass to Pecan Island, LA...2-4 ft Overtopping of local levees outside of the Hurricane and Storm Damage Risk Reduction System is possible where local inundation values may be higher than those shown above. The deepest water will occur along the immediate coast near and to the east of the landfall location, where the surge will be accompanied by large and dangerous waves. Surge-related flooding depends on the relative timing of the surge and the tidal cycle, and can vary greatly over short distances. For information specific to your area, please see products issued by your local National Weather Service forecast office. WIND: Hurricane and tropical storm conditions are occuring over the Isle of Youth and portions of western Cuba and will continue through tonight in western Cuba. Hurricane conditions are expected in the hurricane warning area along the northern Gulf coast beginning Sunday with tropical storm conditions expected to begin by late Saturday night. RAINFALL: Ida is expected to produce total rainfall accumulations of 6 to 10 inches with maximum totals of 15 inches across Jamaica. Rainfall totals of 8 to 12 inches with isolated maximum amounts of 20 inches are expected across the Cayman Islands and western Cuba, including the Isle of Youth. These rainfall amounts may produce life-threatening flash floods and mudslides. As Ida approaches the central Gulf Coast Sunday afternoon, total rainfall accumulations of 8 to 16 inches with isolated maximum amounts of 20 inches are possible from southeast Louisiana to coastal Mississippi and Alabama through Monday morning. This is likely to result in considerable flash, urban, small stream, and riverine flooding impacts. Ida is forecast to turn northeast as it moves inland later Monday with rainfall totals of 4 to 8 inches possible across southern and central Mississippi into the Tennessee Valley. This is likely to result in flash, urban, small stream, and riverine flooding impacts. SURF: Swells generated by this system will affect the Cayman Islands and Cuba through tonight. Swells will begin reaching portions of the northern Gulf coast Saturday night or early Sunday. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. NEXT ADVISORY ------------- Next intermediate advisory at 800 PM EDT. Next complete advisory at 1100 PM EDT. $$ Forecaster Brown |