1. Tropical storm conditions will spread northward along the east coast of Florida within the warning area through early Monday and will reach the coasts of Georgia, South Carolina, and southern North Carolina within the warning area Monday and early Tuesday.

2. Dangerous storm surge is possible from Edisto Beach South Carolina to Cape Fear North Carolina where water rises of 2 to

4.feet above ground level are possible along the immediate coastline and adjacent waterways. A Storm Surge Warning may be needed for a portion of this area later today, and residents there should follow advice given by local emergency officials.

3. Heavy rainfall from Isaias will continue to result in potentially life-threatening flash flooding in the Northwest Bahamas through tonight. Flash and urban flooding, some of which may be significant in the coastal Carolinas and Virginia, is expected through midweek along and near the path of Isaias along the U.S. East Coast. Widespread minor to isolated moderate river flooding is possible across portions of the Carolinas and Mid-Atlantic.4. A Tropical Storm Watch is in effect for portions of the North Carolina coast, where tropical storm conditions are possible on Tuesday. Additional watches and warnings will likely be issued later today as Isaias is expected to move northward near or over the mid-Atlantic and northeast coasts Tuesday and Wednesday.

CHANGES WITH THIS ADVISORY:

None.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Watch is in effect for...
- Edisto Beach South Carolina to Cape Fear North Carolina

A Tropical Storm Warning is in effect for...
- Jupiter Inlet Florida to Surf City North Carolina

A Tropical Storm Watch is in effect for...
- North of Surf City to Duck North Carolina
- Pamlico and Albemarle Sounds

Interests elsewhere along the midAtlantic coast of the United States should monitor the progress of Isaias. Additional watches or warnings may be required later today.

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 Warning means that tropical storm conditions are expected somewhere within the warning area, generally within 36 hours.

A Tropical Storm Watch means that tropical storm conditions are possible within the watch area, generally within 48 hours.

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.

Key messages for Isaias 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.

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...

Edisto Beach SC to Cape Fear NC...24 ft Jupiter Inlet FL to Edisto Beach SC...13 ft

The deepest water will occur along the immediate coast in areas of onshore winds, where the surge will be accompanied by large waves. Surgerelated 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: Tropical storm conditions are expected to spread northward along the coast of Florida within the warning area through tonight. These conditions will spread northward along the coasts of Georgia, South Carolina, and North Carolina within the warning area on Monday and Tuesday.

Tropical storm conditions are possible in the watch area in North Carolina on Tuesday.

RAINFALL: The following rainfall accumulations are expected along and near the track of Isaias:

Northwest Bahamas: 4 to 8 inches, with isolated maximum totals of 12 inches.

Eastern Florida: 2 to 4 inches, with isolated maximum totals of 6 inches.

Northeast Florida and coastal Georgia: 1 to 3 inches.

Carolinas and the mid Atlantic: 3 to 5 inches, with isolated maximum totals of 7 inches.

Southeast New York and much of New England: 2 to 4 inches, with isolated maximum totals of 6 inches.

Heavy rainfall from Isaias will continue to result in potentially lifethreatening flash flooding in the Northwest Bahamas through tonight. Flash and urban flooding, some of which may be significant in the coastal Carolinas and Virginia, is expected through midweek along and near the path of Isaias across the East Coast of the United States. Widespread minor to isolated moderate river flooding is possible across portions of the Carolinas and MidAtlantic.

SURF: Swells generated by Isaias are affecting portions of the Bahamas and the southeast coast of the United States and will spread northward along the U.S. east coast during the next few days. These swells are likely to cause lifethreatening surf and rip current conditions. Please consult products from your local weather office.

TORNADOES: The potential for a couple tornadoes will begin along coastal South Carolina during the late afternoon and evening on Monday, spreading across eastern North Carolina on Monday night.

At 200 PM EDT (1800 UTC), the center of Tropical Storm Isaias was located by an Air Force Reserve reconnaissance aircraft and NOAA Doppler weather radar near latitude 27.4 North, longitude 79.7 West. Isaias is moving toward the northnorthwest near 9 mph (15 km/h) and this general motion is expected to continue through Monday morning. A turn toward the north and northnortheast is anticipated on Monday and Tuesday with an increase in forward speed. On the forecast track, the center of Isaias will move near the east coast of Florida today through late tonight. On Monday and Tuesday, the center of Isaias will move from offshore the coast of Georgia into the midAtlantic states.

Data from the aircraft and the Melbourne, Florida, Doppler radar data indicate that maximum sustained winds are near 65 mph (100 km/h) with higher gusts. Some fluctuations in strength will be possible during the next 48 hours.

Tropicalstormforce winds extend outward up to 115 miles (185 km) from the center. During the past couple of hours, the NOAA CMAN station at Settlement Point, Grand Bahama Island, measured a wind gust of 48 mph (78 km/h), and a weather station at Sebastian Inlet, Florida measured a wind gust of 46 mph (74 km/h).

The minimum central pressure based on reports from the reconnaissance aircraft is estimated to be 995 mb (29.39 inches).

Another recent burst of deep convection has recently developed northeast of the center, which has resulted in Isaias making a slight northward jog. An impressive mid-level circulation has developed within the strongest thunderstorm cluster, along with rare reflectivity values of 55-60 dBZ for a tropical cyclone. The Melbourne, Florida, Doppler weather radar has been indicating patches of velocity values of 65-66 kt at around 10,000 ft just north of the center, which equates to 58-59 kt surface winds. For now, the intensity will remain at 55 kt since previous convective bursts have not persisted for more than a couple of hours at best. Another Air Force Reserve Hurricane Hunter aircraft is scheduled to investigate Isaias later today. Radar and aircraft fixes indicate that Isaias is now moving toward the north-northwest or 340/07 kt. A slow north-northwestward motion should continue for the next 24 hours or so as Isaias moves into a weakness that has developed in the Bermuda-Azores ridge over north Florida and off the Georgia coast seen in 02/1200Z upper-air data. A turn toward the north is forecast to occur by all of the global models by Monday morning, followed by a faster forward motion toward the northeast by Monday afternoon and evening when the cyclone will be influenced by southwesterly steering flow ahead of a strong eastward-moving mid- to upper-level trough. Continued northeastward acceleration across the mid-Atlantic and New England states is expected on days 3 and 4. The global models continue to show little cross-track difference, but still have significant along-track differences with the GFS being the fastest and the ECMWF being the slowest . Since the preponderance of the model guidance is slower than the GFS solution, the new official forecast track closely follows the consensus models TVCA and HCCA, and lies near the previous advisory track after 12 h.Isaias will remain over warm Gulfstream waters where water temperatures are near 30 deg C. Despite very unfavorable vertical shear conditions of 25-30 kt the past couple of days, the cyclone has managed to hold together, which is an indication that the system has a deep, well-formed vertical circulation. While some slight intensification is possible if the shear decreases, the official forecast calls for the intensity to remain steady until landfall occurs in the Carolinas in 36 hours or so. Some baroclinic interaction with the right-rear quadrant of an anticyclonically curved jet streak is expected to hold the intensity a little above what would normally be expected for a post-landfall tropical cyclone in 48-72 hours. The NHC intensity forecast is similar to the HFIP corrected consensus model and the IVCN intensity consensus model.