WTNT34 KNHC 031758 CCA
Tropical Storm Isaias Intermediate Advisory Number 26A...Corrected
NWS National Hurricane Center Miami FL AL092020
200 PM EDT Mon Aug 03 2020
Corrected to remove watches and warnings changes
...ISAIAS STILL EXPECTED TO MAKE LANDFALL TONIGHT AS A HURRICANE...
...STRONG WINDS AND HEAVY RAINFALL LIKELY FROM THE EASTERN
CAROLINAS TO THE MID-ATLANTIC COAST TONIGHT AND TUESDAY...
SUMMARY OF 200 PM EDT...1800 UTC...INFORMATION
ABOUT 115 MI...190 KM S OF CHARLESTON SOUTH CAROLINA
ABOUT 180 MI...290 KM SSW OF MYRTLE BEACH SOUTH CAROLINA
MAXIMUM SUSTAINED WINDS...70 MPH...110 KM/H
PRESENT MOVEMENT...N OR 5 DEGREES AT 13 MPH...20 KM/H
MINIMUM CENTRAL PRESSURE...993 MB...29.32 INCHES
WATCHES AND WARNINGS
CHANGES WITH THIS ADVISORY:
SUMMARY OF WATCHES AND WARNINGS IN EFFECT:
A Storm Surge Warning is in effect for...
* Edisto Beach South Carolina to Cape Fear North Carolina
* Pamlico and Albemarle Sounds, including the Neuse and Pamlico
* Oregon Inlet North Carolina to the North Carolina/Virginia border
A Storm Surge Watch is in effect for...
* Cape Fear to Oregon Inlet North Carolina
A Hurricane Warning is in effect for...
* South Santee River South Carolina to Surf City North Carolina
A Tropical Storm Warning is in effect for...
* Altamaha Sound Georgia to South Santee River South Carolina
* North of Surf City North Carolina to the Mouth of the Merrimack
* Pamlico and Albemarle Sounds
* Chesapeake Bay
* Tidal Potomac River
* Delaware Bay
* Long Island and Long Island Sound
* Martha's Vineyard, Nantucket, and Block Island
A Tropical Storm Watch is in effect for...
* Mouth of the Merrimack River to Eastport Maine
Interests elsewhere along the northeast coast of the United States
should monitor the progress of Isaias. Additional watches or
warnings may be required later today.
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 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
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 Warning means that hurricane conditions are expected
somewhere within the warning area, in this case within 24 hours.
Preparations to protect life and property should be rushed to
A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area, generally within 36
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, including possible
inland watches and warnings, please monitor products issued by your
local National Weather Service forecast office.
DISCUSSION AND OUTLOOK
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 radars near latitude 31.2 North, longitude 80.0
West. Isaias is moving toward the north near 13 mph (20 km/h), and
this general motion is expected to continue this afternoon. A turn
toward the north-northeast along with a slight increase in forward
speed is expected by early this evening, followed by a faster motion
tonight and Tuesday. On the forecast track, the center of Isaias
will pass well east of the Georgia coast through this afternoon.
The center of Isaias will then approach the coasts of northeastern
South Carolina and southern North Carolina within the hurricane
warning area this evening. The center will then move inland over
eastern North Carolina tonight, and move along the coast of the
mid-Atlantic states on Tuesday and into the northeastern United
States Tuesday night.
Data from the reconnaissance aircraft and NOAA Doppler weather
radars indicate that maximum sustained winds remain near 70 mph (110
km/h) with higher gusts. Some strengthening is forecast this
afternoon or early evening, and Isaias is expected to regain
hurricane strength just before the cyclone reaches the coast of
northeastern South Carolina or southern North Carolina tonight. Only
slow weakening is anticipated after Isaias makes landfall in the
Carolinas and moves across the U.S. mid-Atlantic region tonight and
Tropical-storm-force winds extend outward up to 125 miles (205 km)
from the center. During the past hour, a wind gust to 40 mph (65
km/h) occurred at Folly Island Pier, South Carolina, and at COMRP
buoy 41033 located just offshore Fripp Island, South Carolina.
The estimated minimum central pressure based on recent reports from
the aircraft is 993 mb (29.32 inches).
HAZARDS AFFECTING LAND
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...
South Santee River SC to Cape Fear NC...3-5 ft
Edisto Beach SC to South Santee River SC...2-4 ft
Cape Fear NC to the North Carolina/Virginia border including Pamlico
Sound, Albemarle Sound, Neuse and Pamlico Rivers...2-4 ft
Altamaha Sound GA to Edisto Beach SC...1-3 ft
North of the North Carolina/Virginia border to Martha's Vineyard
including the Chesapeake Bay, the Tidal Potomac River, Delaware Bay,
Long Island Sound, Block Island Sound, Narragansett Bay, Buzzards
Bay, and Vineyard Sound…1-3 ft
The deepest water will occur along the immediate coast in areas of
onshore winds, where the surge will be accompanied by large 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 conditions are expected within the hurricane
warning area in South and North Carolina this evening through
tonight, with tropical storm conditions beginning later today.
Widespread tropical-storm-conditions are expected in the
tropical storm warning area from coastal North Carolina to the
mid-Atlantic states tonight and Tuesday, with wind gusts to
hurricane force possible. These winds could cause tree damage and
Tropical storm conditions are expected to reach southern New
England late Tuesday and are possible along the northern New
England coast Tuesday night and early Wednesday.
RAINFALL: The following rainfall accumulations are expected along
and near the track of Isaias:
Carolinas and the Mid-Atlantic: 3 to 6 inches, isolated maximum
totals 8 inches.
Southeast New York and much of New England: 2 to 4 inches, isolated
maximum totals 6 inches.
Heavy rainfall from Isaias will result in flash and urban flooding,
some of which may be significant in the eastern Carolinas and the
mid-Atlantic, through Tuesday night near the path of Isaias up the
East Coast of the United States. Widespread minor to moderate river
flooding is possible across portions of the Carolinas and the
mid-Atlantic. Additionally, quick-responding rivers in the southern
Appalachians and Northeast will be susceptible to minor river
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 couple of days.
These swells are likely to cause life-threatening surf and rip
current conditions. Please consult products from your local weather
TORNADOES: A few tornadoes will be possible over coastal South
Carolina beginning this evening, spreading across eastern North
Carolina tonight into Tuesday morning. A couple tornadoes will be
possible on Tuesday from eastern Virginia northeastward into
southern New England.
Next complete advisory at 500 PM EDT.