| Track: https://www.nhc.noaa.gov/refresh/graphics_at4+shtml/?cone#contents Satellite Floater: https://www.star.nesdis.noaa.gov/GOES/floater.php?stormid=AL292020 Since the track has shifted nearer to me again, I guess I am likely to get some rain from it. Have gotten a little already that I guess is kind of from it. Track is still uncertain. Tropical Storm Eta Discussion Number 42 NWS National Hurricane Center Miami FL AL292020 300 PM CST Tue Nov 10 2020 Eta's convective structure has changed little since the previous advisory. A CDO-like feature with cloud tops colder than -70C has persisted, with some overshooting tops of -80C to -85C located east and southeast of the center. Recent passive microwave satellite data indicates that Eta is still sheared from the northwest, with an intermittent mid-level eye feature showing up. Satellite classifications have essentially remained unchanged, with SAB reporting 45-55 kt and TAFB reporting 55 kt. The initial intensity remains at 50 kt based on a blend of these satellite classifications and a UW-CIMSS SATCON estimates of 45-48 kt. The initial motion estimate is now northward, or 360/06 kt. The biggest surprise is the large eastward shift in all of the NHC model guidance, which was possibly due at least in part to all of the dropsondes that the NOAA G-IV jet aircraft dropped around Eta earlier this morning, All of the guidance is now in good agreement on a broad, deep-layer trough moving eastward across the south-central and southeastern United States, which will erode the subtropical ridge to the north of Eta that has been impeding Eta's poleward progress he past couple of days. This generally northward to northeastward steering pattern is expected to persist through the entire 120-h forecast period, with only slight shifts east or west of he current forecast track due to how vertically deep Eta remains when it reaches the northeastern Gulf of Mexico and Apalachee Bay in a few days. The current forecast track maintains Eta as at least a moderate tropical cyclone through the period, with only a slight bend back toward the northwest when the system is expected to interact with an approaching frontal system. The new NHC track forecast has been shifted about 150 n mi east of the previous advisory track at 96 and 120 hours, and further eastward shifts in the track may be required, closer to the consensus models TCVA/TVCN and NOAA-HCCA. Eta is forecast to remain in a low-to-moderate vertical wind shear environment and over SSTs of at least 27 deg C for the next 36 hours or so. Intermittent entrainment of dry mid-level air should prevent any rapid strengthening from occurring, but Eta could still become a hurricane between in 24 to 36 h before more significant shear begins to affect the cyclone. By day 3 and beyond, increasing northwesterly vertical wind shear combined with cooler SSTs should cause Eta to weaken. The new intensity forecast is essentially the same as the previous advisory, and is a little below the consensus models IVCN, HCCA, and FSSE, all of which make Eta a hurricane again by 36 hours. Due to the expected northwesterly shear after 36 hours, the 34-kt wind radii were expanded in the eastern semicircle, which is the side of the cyclone where most of the deep convection and associated stronger winds will be located. Given this and the eastward adjustment to the track forecast, a Tropical Storm Watch has been issued for portions of the Florida west coast, and a Tropical Storm Warning is in effect for the Dry Tortugas. Key Messages: 1. Tropical-storm-force winds are possible along portions of the Florida Gulf Coast by Thursday afternoon, and a Tropical Storm Watch has been issued. Interests elsewhere along the Florida Gulf Coast should monitor the progress of Eta, as additional watches may be needed tonight. 2. Heavy rainfall from Eta will continue across western Cuba and South Florida today and tonight, then potentially spread up the west coast of the Florida Peninsula Wednesday through Thursday. Additional flash and urban flooding will be possible in South Florida, especially across previously inundated areas, and eventually along portions of West Florida and the Sun Coast. Flash and urban flooding will also be possible for western Cuba. FORECAST POSITIONS AND MAX WINDS INIT 10/2100Z 23.2N 85.1W 50 KT 60 MPH 12H 11/0600Z 24.1N 84.9W 55 KT 65 MPH 24H 11/1800Z 25.6N 84.8W 60 KT 70 MPH 36H 12/0600Z 26.9N 84.5W 60 KT 70 MPH 48H 12/1800Z 27.9N 84.2W 55 KT 65 MPH 60H 13/0600Z 28.7N 84.0W 45 KT 50 MPH 72H 13/1800Z 29.1N 84.0W 40 KT 45 MPH 96H 14/1800Z 29.7N 84.6W 35 KT 40 MPH 120H 15/1800Z 30.7N 84.9W 30 KT 35 MPH...INLAND $$ Forecaster Stewart Tropical Storm Eta Advisory Number 42 NWS National Hurricane Center Miami FL AL292020 300 PM CST Tue Nov 10 2020 ...TROPICAL STORM WARNING ISSUED FOR THE DRY TORTUGAS AND A TROPICAL STORM WATCH IN EFFECT FOR PORTIONS OF THE WEST COAST OF FLORIDA... ...RISK OF FLOODING OVER SOUTH FLORIDA AND WESTERN CUBA CONTINUES... SUMMARY OF 300 PM CST...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...23.2N 85.1W ABOUT 90 MI...145 KM N OF THE WESTERN TIP OF CUBA MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/H PRESENT MOVEMENT...N OR 360 DEGREES AT 7 MPH...11 KM/H MINIMUM CENTRAL PRESSURE...992 MB...29.30 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: A Tropical Storm Warning has been issued for the Dry Tortugas. A Tropical Storm Watch has been issued for the west coast of Florida from Englewood northward to Suwannee River. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Tropical Storm Warning is in effect for... * Dry Tortugas A Tropical Storm Watch is in effect for... * Englewood to Suwannee River Florida * The Cuban provinces of La Habana, Artemisa, Mayabeque, Pinar del Rio, and the Isle of Youth A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area within 36 hours. A Tropical Storm Watch means that tropical storm conditions are possible within the watch area, generally within 48 hours. Interests elsewhere along the Gulf Coast of Florida should monitor the progress of Eta. For storm information specific to your area, please monitor products issued by your national meteorological service. DISCUSSION AND OUTLOOK ---------------------- At 300 PM CST (2100 UTC), the center of Tropical Storm Eta was located by satellite and Cuban radar data near latitude 23.2 North, longitude 85.1 West. Eta is moving toward the north near 7 mph (11 km/h). A motion toward the north or north-northeast is forecast through Wednesday night, followed by a turn toward the northeast on Thursday. On the forecast track the center of Eta will move parallel to but offshore of the Florida west coast on Thursday and move near or over Apalachee Bay Thursday night and Friday. Maximum sustained winds are near 60 mph (95 km/h) with higher gusts. Some strengthening is forecast through Thursday morning, and Eta could be near hurricane strength by Wednesday night or Thursday morning. Gradual weakening is expected to begin Thursday afternoon or evening. Satellite-derived wind data indicate that tropical-storm-force winds extend outward up to 60 miles (95 km) from the center. The estimated minimum central pressure is 992 mb (29.30 inches). HAZARDS AFFECTING LAND ---------------------- Key messages for Eta can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDAT4, WMO header WTNT44 KNHC, and on the web at www.hurricanes.gov/text/MIATCDAT4.shtml. RAINFALL: Eta is expected to produce the following rainfall amounts today and tonight: Western Cuba: an additional 3 to 5 inches (75 to 125 mm), with isolated maximum storm total accumulations of 25 inches (765 mm). South Florida: Isolated additional rainfall amounts of 1 to 2 inches, with isolated maximum storm total accumulations of 15 to 20 inches. Eta is expected to produce the following rainfall amounts through Thursday: Portions of West Florida and the Sun Coast, including the Tampa Bay area: 1 to 2 inches, with isolated totals of 4 inches. Flash and river flooding will be possible in western Cuba, along with landslides in areas of higher terrain. Additional flash and urban flooding will be possible in South Florida, especially across previously inundated areas, and eventually along portions of West Florida and the Sun Coast. Flash and urban flooding will also be possible for western Cuba. WIND: Tropical storm conditions are expected in the Dry Tortugas overnight and early Wednesday. Tropical storm conditions are possible in the Tropical Storm Watch area in Cuba tonight. Tropical storm conditions are possible in the Tropical Storm Watch area along the Florida west coast by Thursday afternoon. SURF: Swells generated by Eta are expected to affect the north coast of Cuba, the northwestern Bahamas, southern and western Florida, and the Florida Keys during the next day or so. 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 600 PM CST. Next complete advisory at 900 PM CST. $$ Forecaster Stewart |