| Track: https://www.nhc.noaa.gov/refresh/graphics_at5+shtml/?cone#contents Experimental Peak Storm Surge Forecast: https://www.nhc.noaa.gov/refresh/graphics_at5+shtml/?peakSurge#contents Tropical Storm Elsa Discussion Number 24 NWS National Hurricane Center Miami FL AL052021 500 AM EDT Tue Jul 06 2021 Elsa is now located over the Florida Straits, with tropical-storm-force wind gusts occurring across the Lower and Middle Keys. Doppler radar data and satellite images indicate that the core of Elsa is fairly small and has maximum winds of around 50 kt. The outer rainbands associated with Elsa are spreading northward across southern Florida, and a cluster of deep convection has been lingering over portions of central and western Cuba. The Air Force Hurricane Hunters will be investigating Elsa later this morning, and the data the plane collects will be valuable in assessing the storm's intensity and structure. Elsa is moving to the north-northwest at about 10 kt on the western periphery of a subtropical ridge that is located over the central Atlantic. The storm should turn northward later today as it moves in the flow between the ridge and a mid- to upper-level low over the south-central U.S. This motion should take the core of Elsa parallel to and likely just offshore of the west coast of Florida through tonight. After that time, a slight turn to the north-northeast is forecast as another trough moves across the north-central U.S. This slight change in heading should bring Elsa inland across the Big Bend region of Florida by early Wednesday and then across coastal Georgia and the Carolinas Wednesday night through early Friday. Thereafter, the storm is expected to accelerate and move northeastward off the mid-Atlantic and New England coasts. The NHC track forecast is basically unchanged from the previous one and lies close to the model consensus aid TVCA. Now that Elsa is gradually pulling away from Cuba, it will have an opportunity to strengthen. However, the environmental conditions are only marginal for the storm to do so. Dry air on the western side of the cyclone and some westerly shear should prevent rapid intensification, but the small cyclone will likely strengthen slowly before it moves inland over the Big Bend of Florida. The GFS model shows Elsa deepening by 5-10 mb before landfall, and the ECMWF shows even greater pressure falls. Based on these models, the intensity forecast is nudged upward and now shows Elsa just below hurricane force before landfall in Florida. After Elsa moves inland, steady weakening is forecast, but the system is expected to restrengthen over the western Atlantic as it transitions into an extratropical cyclone. Based on this new forecast, a Hurricane Watch has been issued for a portion of the west-central and Big Bend Florida coast. In addition, it should be noted that much of the west coast of the Florida Peninsula is expected to see wind, rain, and surge impacts since that region will be on Elsa's east side. A Tropical Storm Watch has also been issued for the Georgia coast and portions of the South Carolina coast. Key Messages: 1. Heavy rain will impact Cuba today resulting in significant flooding and mudslides. As Elsa moves across the western Florida Peninsula through Wednesday, heavy rainfall may result in isolated flash, urban, and minor river flooding, with considerable flash and urban flooding possible in southwest and western portions of Florida. Mid to late week, heavy rainfall across coastal Georgia, South Carolina, North Carolina, and southeastern Virginia may result in isolated flash and urban flooding, with considerable flash and urban flooding possible across coastal Georgia and the Lowcountry of South Carolina. 2. There is a danger of life-threatening storm surge along portions of the west coast of Florida tonight and Wednesday, and a Storm Surge Warning is in effect for that area. 3. A Hurricane Watch has been issued for a portion of the west-central and Big Bend coast of Florida, where hurricane conditions are possible tonight and early Wednesday. Tropical storm conditions are expected across portions of the Florida Keys and much of the west coast of the state, where a Tropical Storm Warning is in effect. 4. A Tropical Storm Watch has been issued for the Georgia coast and portions of the South Carolina coast, where tropical storm conditions are possible late Wednesday and early Thursday. FORECAST POSITIONS AND MAX WINDS INIT 06/0900Z 24.1N 82.4W 50 KT 60 MPH 12H 06/1800Z 25.7N 82.9W 55 KT 65 MPH 24H 07/0600Z 28.0N 83.1W 60 KT 70 MPH 36H 07/1800Z 30.4N 82.5W 40 KT 45 MPH...INLAND 48H 08/0600Z 32.9N 81.0W 30 KT 35 MPH...INLAND 60H 08/1800Z 35.5N 78.2W 30 KT 35 MPH...INLAND 72H 09/0600Z 38.5N 74.3W 35 KT 40 MPH...OVER WATER 96H 10/0600Z 45.9N 62.8W 40 KT 45 MPH...POST-TROP/EXTRATROP 120H 11/0600Z 54.7N 48.4W 35 KT 40 MPH...POST-TROP/EXTRATROP $$ Forecaster Cangialosi/Reinhart Tropical Storm Elsa Advisory Number 24 NWS National Hurricane Center Miami FL AL052021 500 AM EDT Tue Jul 06 2021 ...ELSA NEAR THE FLORIDA KEYS... ...HURRICANE WATCH HAS BEEN ISSUED FOR PORTIONS OF THE WEST COAST OF FLORIDA... SUMMARY OF 500 AM EDT...0900 UTC...INFORMATION ---------------------------------------------- LOCATION...24.1N 82.4W ABOUT 50 MI...80 KM SW OF KEY WEST FLORIDA ABOUT 270 MI...435 KM S OF TAMPA FLORIDA MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/H PRESENT MOVEMENT...NNW OR 340 DEGREES AT 12 MPH...19 KM/H MINIMUM CENTRAL PRESSURE...1007 MB...29.74 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: A Hurricane Watch has been issued for the west-central and Big Bend coast of Florida from Egmont Key to the Steinhatchee River. A Tropical Storm Watch has been issued for the Georgia coast and portions of the South Carolina coast from the Mouth of St. Marys River to South Santee River, South Carolina. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Storm Surge Warning is in effect for... * West coast of Florida from Bonita Beach to the Aucilla River, including Tampa Bay A Tropical Storm Warning is in effect for... * The Cuban provinces of Matanzas, Mayabeque, Havana, and Artemisa * The Florida Keys from Craig Key westward to the Dry Tortugas * West coast of Florida from Flamingo northward to Ochlockonee River A Hurricane Watch is in effect for... * Egmont Key to the Steinhatchee River, Florida A Storm Surge Watch is in effect for... * West of the Aucilla River to the Ochlockonee River, Florida A Tropical Storm Watch is in effect for... * West of the Ochlockonee River to Indian Pass, Florida * Mouth of St. Marys River to South Santee River, South Carolina 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 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 Warning means that tropical storm conditions are expected somewhere within the warning area. 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. For a depiction of areas at risk, please see the National Weather Service Storm Surge Watch/Warning Graphic, available at hurricanes.gov. A Tropical Storm Watch means that tropical storm conditions are possible within the watch area. Interests elsewhere in the Carolinas and the mid-Atlantic coast should monitor the progress of Elsa. 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 AM EDT (0900 UTC), the center of Tropical Storm Elsa was located near latitude 24.1 North, longitude 82.4 West. Elsa is moving toward the north-northwest near 12 mph (19 km/h) and this general motion is expected to continue today, followed by a turn toward the north by tonight. A north-northeastward motion is expected on Wednesday. On the forecast track, Elsa will pass near the Florida Keys this morning, and move near or over portions of the west coast of Florida later today and continuing into Wednesday. Maximum sustained winds remain near 60 mph (95 km/h) with higher gusts. Slow strengthening is forecast through tonight, and Elsa could be near hurricane strength before it makes landfall in Florida. Weakening is expected after it moves inland. Tropical-storm-force winds extend outward up to 70 miles (110 km) from the center. A C-MAN station at Sand Key, Florida, recently measured a wind gust of 45 mph (72 km/h). The estimated minimum central pressure is 1007 mb (29.74 inches). HAZARDS AFFECTING LAND ---------------------- Key messages for Elsa can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDAT5, WMO header WTNT45 KNHC and on the web at www.hurricanes.gov/graphics_at5.shtml?key_messages. WIND: Tropical storm conditions should continue over portions of central and western Cuba during the next several hours. Tropical storm conditions are beginning in the warning area in the Florida Keys and are expected along the Florida west coast later today. Tropical storm conditions are expected to spread northward into west-central Florida and the Florida Big Bend region tonight and early Wednesday, where hurricane conditions are possible. Tropical storm conditions are possible in the watch area in Florida beginning late tonight and in Georgia and South Carolina Wednesday night and early Thursday. STORM SURGE: A storm surge will raise water levels above normal tide levels by as much as the following amounts in areas of onshore winds within the Tropical Storm Warning areas... Southern coast of Cuba...2 to 4 ft The combination of a 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... Englewood, FL to Aucilla River including Tampa Bay...3 to 5 ft Bonita Beach, FL to Englewood, FL including Charlotte Harbor...2 to 4 ft Aucilla River to Ochlockonee River...2 to 4 ft Flamingo, FL to Bonita Beach, FL...1 to 3 ft Craig Key, FL to Dry Tortugas...1 to 2 ft Ochlockonee River to Indian Pass...1 to 2 ft 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. RAINFALL: Across portions of Cuba through tonight, rainfall of 5 to 10 inches with isolated maximum amounts of 15 inches is expected. This will result in significant flash flooding and mudslides. Elsa is expected to produce the following rainfall amounts and impacts this week: Across the Florida Keys into southwest and western portions of the Florida Peninsula...3 to 5 inches with localized maximum totals up to 8 inches through Wednesday, which may result in considerable flash and urban flooding, along with minor to isolated moderate river flooding. Across the rest of Florida...2 to 4 inches with localized maximum totals up to 6 inches through Wednesday night, which may result in isolated flash, urban, and minor river flooding. Across portions of southeast Georgia and the Lowcountry of South Carolina, 3 to 5 inches with isolated maximum totals up to 8 inches will be possible, which may result in considerable flash and urban flooding. Across coastal portions of North Carolina into southeastern Virginia...1 to 3 inches with isolated totals up to 5 inches Wednesday night through Thursday night, which could lead to isolated flash and urban flooding. TORNADOES: A few tornadoes are possible today through tonight across the Florida Peninsula. The tornado threat will continue on Wednesday across north Florida, southeast Georgia, and the Lowcountry of South Carolina. The tornado threat should shift to the eastern Carolinas and far southeast Virginia on Thursday. SURF: Swells will spread northward across portions of the Florida Keys and the west coast of Florida through early Wednesday. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office for more details. NEXT ADVISORY ------------- Next intermediate advisory at 800 AM EDT. Next complete advisory at 1100 AM EDT. $$ Forecaster Cangialosi/Reinhart U.S. rainfall potential from the NHC: https://www.nhc.noaa.gov/refresh/graphics_at5+shtml/?rainqpf#contents Or from WPC: https://www.wpc.ncep.noaa.gov/#page=qpf Tides: https://tidesandcurrents.noaa.gov/inundationdb/storm/Elsa.html River levels: https://water.weather.gov/ahps/region.php?state=fl Satellite floater: https://www.star.nesdis.noaa.gov/GOES/floater.php?stormid=AL052021 More satellite imagery: http://hurricanecity.com/models/models.cgi?basin=al&year=2021&storm=05#satellite Global Models: GFS: https://www.tropicaltidbits.com/analysis/models/?model=gfs®ion=seus&pkg=mslp_uv850 Euro: https://www.tropicaltidbits.com/analysis/models/?model=ecmwf®ion=seus&pkg=mslp_uv850 Radar: SFWMD's radar which shows current NHC track and radar data: https://www.sfwmd.gov/weather-radar/current-weather-conditions Multi-Radar Multi-Sensor (MRMS) System radar: https://mrms.nssl.noaa.gov/qvs/product_viewer/index.php?time_mode=update&zoom=7&clon=-82&clat=26&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 Wundermap radar: https://www.wunderground.com/wundermap?lat=26&lon=-80&zoom=7&radar=1&wxstn=0&storm-cells=0 Old Weather Underground radar display which doesn't work very well any longer: https://www.wunderground.com/radar/us/fl/key-west/byx |