Very near landfall now.
Here is a link to the recon observation they reference below in the NHC discussion:
http://hurricanecity.com/recon/recon.cgi?basin=al&year=2020&product=hdob&storm=Isaias&mission=25&agency=AF&ob=08-04-003700-22-985.2-109-75
Flight level at around 10,000 feet, 700mb pressure surface, had 30 second winds of 125mph (109 knots), 10 second of 135mph (117 knots), while SFMR, the 10 second estimated surface winds in that region were 86mph (75 knots). That is a really big difference. It's a good thing the center doesn't have more time over water before imminent North Carolina landfall. It certainly doesn't look like it had winds like that at flight level based on satellite, but those are measured. SFMR is the one that is an estimate.
Hurricane Isaias Discussion Number 28
NWS National Hurricane Center Miami FL AL092020
1100 PM EDT Mon Aug 03 2020
NWS Doppler radar data and reports from an Air Force Reserve
Hurricane Hunter aircraft indicate that Isaias re-intensified to a
hurricane despite a less than impressive appearance in satellite
imagery. The aircraft reported 117 kt winds at 700 mb to the
east of the center, but these were not mixed to the surface by
the weak convection in that area, as the maximum SFMR winds were 75
kt. Based on these data, the initial intensity is raised to 75 kt.
The hurricane is moving 020/19, and a faster forward speed is
expected as the system moves farther into the mid-latitude
southwesterly flow. This should bring the center onshore in
southern North Carolina shortly, followed by a track through the
mid-Atlantic and western New England states Tuesday and Tuesday
night and into southeastern Canada early Wednesday.
Interaction with a strong jet stream suggests that Isaias should
weaken more slowly than normal as it moves through the eastern
United States, and this should produce very strong wind gusts along
the mid-Atlantic coast tomorrow. As a result, the gust factors at
24-48 h have been increased above the standard 20 percent in the
Forecast/Advisory (TCMAT4). The cyclone is forecast to be absorbed
by a larger extratropical low over Canada in about 72 h.
Key Messages:
1. There is the danger of life-threatening storm surge inundation
along portions of the immediate coastline and adjacent waterways of
northeastern South Carolina and the North Carolina coast, including
portions of Pamlico and Albemarle Sounds. Residents in these
areas should follow advice given by local emergency officials.
2. Hurricane conditions are spreading into the southern portion of
the hurricane Warning area and should spread northward through
tonight and early tomorrow morning.
3. Isaias is expected to bring widespread sustained tropical storm
force winds and wind gusts to hurricane force to the mid-Atlantic
coast, including portions of the Chesapeake Bay region, later
tonight and on Tuesday, which could cause tree damage and power
outages. Tropical storm conditions are expected to spread across
New England late Tuesday into early Wednesday.
4. Heavy rainfall along the East Coast near the path of Isaias will
result in flash and urban flooding, some of which may be significant
in the eastern Carolinas, mid-Atlantic and northeast through
Wednesday. Widespread minor to moderate river flooding is possible
across portions of the Carolinas and the Mid-Atlantic. Quick-
responding rivers in the northeast will also be susceptible to minor
river flooding.
FORECAST POSITIONS AND MAX WINDS
INIT 04/0300Z 33.8N 78.5W 75 KT 85 MPH
12H 04/1200Z 37.0N 76.8W 60 KT 70 MPH...INLAND
24H 05/0000Z 42.0N 73.8W 50 KT 60 MPH...INLAND
36H 05/1200Z 46.8N 70.4W 40 KT 45 MPH...INLAND
48H 06/0000Z 50.8N 68.3W 30 KT 35 MPH...POST-TROP/EXTRATROP
60H 06/1200Z 52.9N 66.3W 25 KT 30 MPH...POST-TROP/EXTRATROP
72H 07/0000Z...DISSIPATED
$$
Forecaster Beven
Hurricane Isaias Advisory Number 28
NWS National Hurricane Center Miami FL AL092020
1100 PM EDT Mon Aug 03 2020
...HURRICANE CONDITIONS SPREADING ONTO THE COAST OF EASTERN SOUTH
CAROLINA AND SOUTHEASTERN NORTH CAROLINA...
...STRONG WINDS AND HEAVY RAINFALL LIKELY FROM THE EASTERN
CAROLINAS TO THE MID-ATLANTIC COAST TONIGHT AND TUESDAY...
SUMMARY OF 1100 PM EDT...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...33.8N 78.5W
ABOUT 25 MI...40 KM ENE OF MYRTLE BEACH SOUTH CAROLINA
ABOUT 50 MI...80 KM SW OF WILMINGTON NORTH CAROLINA
MAXIMUM SUSTAINED WINDS...85 MPH...140 KM/H
PRESENT MOVEMENT...NNE OR 20 DEGREES AT 22 MPH...35 KM/H
MINIMUM CENTRAL PRESSURE...988 MB...29.18 INCHES
WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:
A Storm Surge Warning is now in effect from Ocracoke Inlet North
Carolina to Oregon Inlet North Carolina.
A Tropical Storm Warning is now in effect north of Stonington Maine
to Eastport Maine.
The Tropical Storm Warning and Storm Surge Warning south of the
South Santee River has been discontinued.
SUMMARY OF WATCHES AND WARNINGS IN EFFECT:
A Storm Surge Warning is in effect for...
* South Santee River South Carolina to Cape Fear North Carolina
* Pamlico and Albemarle Sounds, including the Neuse and Pamlico
Rivers
* Ocracoke Inlet North Carolina to the North Carolina/Virginia
border
A Storm Surge Watch is in effect for...
* Cape Fear to Ocracoke 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...
* North of Surf City North Carolina to Eastport Maine
* 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 Storm Surge Warning means there is a danger of life-threatening
inundation, from rising water moving inland from the coastline,
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 officials.
A Storm Surge Watch means there is a possibility of life-
threatening inundation, from rising water moving inland from the
coastline.
A Hurricane Warning means that hurricane conditions are expected
somewhere within the warning area.
A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area, generally within 36
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 1100 PM EDT (0300 UTC), the center of Hurricane Isaias was
located near latitude 33.8 North, longitude 78.5 West. Isaias is
moving toward the north-northeast near 22 mph (35 km/h), and this
general motion accompanied by a gradual increase in forward
speed is expected through tonight followed by a further increase in
the forward speed on Tuesday. On the forecast track, the center of
Isaias will make landfall in southern North Carolina during the
next hour or two, then move across eastern North Carolina for the
rest of the night. The center move near or along the coast of the
mid-Atlantic states on Tuesday, and continue across the northeastern
United States Tuesday night.
Maximum sustained winds are near 85 mph (140 km/h) with higher
gusts. Little change in strength is expected before landfall.
After landfall, only gradual weakening is anticipated after Isaias
makes landfall in the Carolinas and moves across the U.S.
mid-Atlantic region tonight and Tuesday.
Hurricane-force winds extend outward up to 25 miles (35 km) from the
center and tropical-storm-force winds extend outward up to 125 miles
(205 km). A station at Frying Pan Shoals, North Carolina, recently
reported sustained winds of 72 mph (116 km/h) and a wind gust of 93
mph (150 km/h).
The estimated minimum central pressure is 988 mb (29.18 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 to South Santee River SC...1-3 ft
Cape Fear to Ocracoke Inlet NC...2-4 ft
Ocracoke Inlet to the North Carolina/Virginia border including
Pamlico Sound, Albemarle Sound, Neuse and Pamlico Rivers...3-5 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 spreading across the southern
portion of the hurricane warning area in South and North Carolina at
this time, with tropical storm conditions spreading onshore farther
to the north.
Widespread tropical-storm conditions are expected in the
tropical storm warning area from coastal North Carolina to the
mid-Atlantic states, including portions of the Chesapeake Bay
region, later tonight and Tuesday, with wind gusts to hurricane
force possible. These winds could cause tree damage and power
outages.
Tropical storm conditions are expected to reach southern New
England Tuesday afternoon and northern New England Tuesday night
and early Wednesday.
Gale-force winds are expected to spread into southeastern Quebec
Tuesday night and Wednesday. See products issued by Environment
Canada for more information.
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.
Eastern New York and western New England from Connecticut to New
Hampshire: 2 to 4 inches, isolated maximum totals 6 inches.
Western and northern Maine: 1 to 3 inches.
Heavy rainfall along the East Coast, near the path of Isaias, will
result in flash and urban flooding, some of which may be significant
in the eastern Carolinas, Mid-Atlantic and Northeast through
Wednesday. Widespread minor to moderate river flooding is possible
across portions of the Carolinas and the Mid-Atlantic.
Quick-responding rivers in Northeast will also be susceptible to
minor river flooding.
TORNADOES: A few tornadoes will be possible across eastern North
Carolina tonight, and from eastern Virginia northeastward into
southern New England on Tuesday.
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
office.
NEXT ADVISORY
-------------
Next intermediate advisory at 200 AM EDT.
Next complete advisory at 500 AM EDT.
$$
Forecaster Beven
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