Subtropical Storm Nicole Discussion Number 2 NWS National Hurricane Center Miami FL AL172022 1100 AM AST Mon Nov 07 2022 The structure of Nicole this morning remains distinctly subtropical, as the low-level circulation remains tangled up with an elongated upper-level low. The wind-field also remains quite broad, with data from the NOAA-P3 Hurricane Hunters this morning showing the highest winds remaining displaced well away from the center. The initial intensity is being held at 40 kt for this advisory which is supported by the subtropical classification of ST2.5/35-40 kt from TAFB, the earlier scatterometer data, and recent SFMR winds from the NOAA-P3 aircraft in the 40-kt range. Nicole might be starting to take a northwestward turn this morning, with the estimated motion at 320/8 kt. A continued northwestward motion is expected through the day, though there might be some wobbles more north or west here and there as the low-level circulation continues to interact with the decaying upper-level low. After 24 hours, an anomalously strong mid-level ridge is expected to amplify over the southeastern U.S. which is expected to steer Nicole and result in the system turning westward or even west-southwestward on Tuesday night into Wednesday. This ridging will then re-position itself to the northeast of Nicole by Thursday and Friday which is expected to allow the cyclone to begin gaining latitude after it moves across the Florida Peninsula, though how quickly this occurs is a source of track uncertainty in this time frame. Finally a broad mid-latitude trough is forecast to eject out of the Rockies into the Great Lakes region, further eroding the ridge and allowing Nicole to recurve by the end of the forecast period. The track guidance is fairly tightly clustered for the first 60 hours of the forecast, though it has taken a noticeable shift southward this cycle, and the NHC track forecast was shifted a bit southward due to this adjustment, but still is a bit north of the HFIP Corrected Consensus Approach (HCCA). Intensity wise, Nicole may take some time to consolidate given its large radius of maximum winds and currently meager central convection due to nearby dry air related to the nearby upper-level low. This feature should gradually decay and warm 27-28 C sea-surface temperatures should enable more organized convection to develop while the system remains in a low vertical wind shear environment. Nicole is forecast to transition to a tropical storm sometime in the 24-36 hour period as this convection helps to contract the radius of maximum wind, with further intensification expected thereafter. The intensity guidance was a bit higher this cycle, and the latest forecast now takes Nicole to a 65-kt hurricane in 60 hours, which is close to the latest HCCA, HMON, and SHIPS guidance. After Nicole moves inland, weakening is anticipated, and the region that Nicole is forecast to emerge off in the northern Gulf of Mexico has cooler SSTs that likely would not support robust reintensification. Regardless on the ultimate intensity of Nicole, the storm's large size due to an enhanced pressure gradient north of the storm will likely cause significant wind, storm surge, and rainfall impacts over a large portion of the northwestern Bahamas, Florida, and the southeastern coast of the United States during much of the upcoming week. Key Messages: 1. Hurricane conditions are possible across portions of the northwestern Bahamas and southeast to east-central Florida beginning Wednesday, where a Hurricane Watch has been issued. Tropical storm conditions are possible in the Tropical Storm Watch areas in Florida and Georgia beginning Wednesday. 2. A dangerous storm surge is possible across portions of the northwestern Bahamas, much of the east coast of Florida and portions of coastal Georgia. A Storm Surge Watch has been issued for most of the east coast of Florida and portions of coastal Georgia. 3. Do not focus on the exact track of Nicole since it is expected to be a large storm with hazards extending well to the north of the center, and outside of the cone, and affect much of the Florida peninsula and portions of the southeast U.S. 4. Nicole will produce heavy rainfall by Wednesday night and Thursday across the Florida Peninsula. Flash and urban flooding will be possible across portions of the Florida Peninsula along with river rises on portions of the St. Johns River. FORECAST POSITIONS AND MAX WINDS INIT 07/1500Z 26.2N 69.4W 40 KT 45 MPH...SUBTROPICAL STORM 12H 08/0000Z 27.0N 70.5W 40 KT 45 MPH...SUBTROPICAL STORM 24H 08/1200Z 27.7N 71.9W 45 KT 50 MPH...SUBTROPICAL STORM 36H 09/0000Z 27.6N 74.1W 55 KT 65 MPH...TROPICAL STORM 48H 09/1200Z 26.9N 76.5W 60 KT 70 MPH 60H 10/0000Z 26.6N 78.7W 65 KT 75 MPH 72H 10/1200Z 27.3N 81.2W 50 KT 60 MPH 96H 11/1200Z 29.4N 83.9W 45 KT 50 MPH 120H 12/1200Z 33.3N 79.0W 45 KT 50 MPH...INLAND $$ Forecaster Papin/Brown Subtropical Storm Nicole Advisory Number 2... Corrected NWS National Hurricane Center Miami FL AL172022 1100 AM AST Mon Nov 07 2022 Corrected to add Lake Okeechobee in the Watch and Warning changes. ...NICOLE REMAINS A SUBTROPICAL STORM AS IT BEGINS TO TURN NORTHWESTWARD... ...HURRICANE AND STORM SURGE WATCHES ISSUED FOR THE EAST FLORIDA COAST... SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION ----------------------------------------------- LOCATION...26.3N 69.6W ABOUT 495 MI...795 KM E OF THE NORTHWESTERN BAHAMAS MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H PRESENT MOVEMENT...NW OR 320 DEGREES AT 9 MPH...15 KM/H MINIMUM CENTRAL PRESSURE...1002 MB...29.59 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: A Hurricane Watch has been issued for the east coast of Florida from the Volusia/Brevard County Line to Hallandale Beach and for Lake Okeechobee. A Storm Surge Watch has been issued for the east coast of Georgia and east coast of Florida from Altamaha Sound southward to Hallandale Beach. The government of the Bahamas has changed the Tropical Storm Watch to a Hurricane Watch for the northwestern Bahamas. A Tropical Storm Watch has been issued for Altamaha Sound, Georgia southward to Volusia/Brevard County Line and south of Hallandale Beach to north of Ocean Reef. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Hurricane Watch is in effect for... * Northwestern Bahamas * East Coast of Florida from the Volusia/Brevard County Line to Hallandale Beach * Lake Okeechobee A Storm Surge Watch is in effect for... * Altamaha Sound to Hallandale Beach A Tropical Storm Watch is in effect for... * Altamaha Sound southward to Volusia Brevard County Line * Hallandale Beach to north of Ocean Reef A Tropical Storm Watch means that tropical storm conditions are possible within the watch area, generally within 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. Interests in the central Bahamas, the remainder of Florida, and along the southeastern coast of the United States should monitor the progress of Nicole. Additional watches will likely be required later today. 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 1100 AM AST (1500 UTC), the center of Subtropical Storm Nicole was located near latitude 26.3 North, longitude 69.6 West. The storm is moving toward the northwest near 9 mph (15 km/h). This motion with a decrease in forward speed is expected later today. A turn westward or west-southwestward is then forecast Tuesday through early Thursday. On the forecast track, the center of Nicole will approach the northwestern Bahamas on Tuesday, move near or over those islands on Wednesday, and approach the east coast of Florida by Wednesday night. Maximum sustained winds are near 45 mph (75 km/h) with higher gusts. Gradual strengthening is forecast during the next few days, and Nicole is forecast to be at hurricane intensity by Wednesday or Wednesday night while it is moving near or over the northwestern Bahamas. Winds of 40 mph extend outward up to 275 miles (445 km) from the center. The estimated minimum central pressure is 1002 mb (29.59 inches). HAZARDS AFFECTING LAND ---------------------- Key messages for Nicole can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDAT2, WMO header WTNT42 KNHC, and on the web at www.hurricanes.gov/text/MIATCDAT2.shtml. WIND: Hurricane conditions are possible within the watch area in the northwest Bahamas by early Wednesday, with tropical storm conditions possible by Tuesday night. Hurricane conditions are possible within the watch area in Florida by Wednesday night with tropical storm conditions possible by Tuesday night. STORM SURGE: 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... *North Palm Beach to Altamaha Sound including the St. Johns River to the Fuller Warren Bridge... 3 to 5 ft *Hallandale Beach to North Palm Beach...2 to 4 ft *North of Ocean Reef to Hallandale Beach including Biscayne Bay...1 to 2 ft Storm surge could raise water levels by as much as 3 to 5 feet above normal tide levels along the immediate coast of the northwestern Bahamas in areas of onshore winds. The deepest water will occur along the immediate coast near and to the north of the landfall location, where the surge will be accompanied by large and destructive 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. RAINFALL: Nicole is expected to produce the following rainfall amounts through Thursday: Across the northwest Bahamas, and the central and northern portions of the Florida Peninsula: 2 to 4 inches, with local maxima of 6 inches Heavy rainfall from this system will spread north across the Southeast United States late this week. NEXT ADVISORY ------------- Next intermediate advisory at 200 PM AST. Next complete advisory at 500 PM AST. $$ Forecaster Papin/Brown |