As Hurricane Erin progresses northward, the coastal regions of North Carolina and Virginia are bracing for significant weather impacts.
At 2 p.m. EDT on Wednesday, Hurricane Erin was situated approximately 335 miles (540 km) south-southeast of Cape Hatteras, North Carolina, moving at a speed of 13 mph (20 km/h).
Satellite images indicate that Erin is intensifying, characterized by a distinct eye and a large area of severe thunderstorms with notably cold cloud top temperatures.
Current assessments reveal that Erin’s sustained winds have escalated to 110 mph (175 km/h), while its central pressure has decreased to 943 mb, marking it as exceptionally low for a storm of this wind speed.
According to hurricane expert Michael Lowry, such low pressure in a hurricane with peak winds below Category 3 is a rare occurrence in the satellite record, previously matched only by storms like Maria in 2017 and Irma in 2017.
The primary threat posed by Hurricane Erin stems from storm surge and high waves, which are anticipated to have serious implications for coastal areas.
Erin is forecasted to make its closest approach, about 250 miles (400 km) east of North Carolina’s coast on Thursday.
However, the effects of tropical storm conditions and coastal flooding are expected to commence as early as Wednesday evening in the Outer Banks region.
Erin’s significant size has contributed to extensive hurricane-force winds reaching up to 105 miles from the center and tropical storm-force winds spanning 265 miles.
This has led to the generation of large, hazardous waves affecting much of the East Coast of North America, as well as the Bahamas and Bermuda.
As these waves combine with Erin’s projected storm surge of two to four feet, communities along North Carolina’s coastline are warned of potential damaging coastal flooding.
The National Oceanic and Atmospheric Administration’s (NOAA) National Water Prediction Service forecasts that Erin’s storm surge could result in substantial flooding at three specific tide gauges during Thursday evening’s high tide.
The Outer Banks area is expected to face the most severe marine impacts, with surf zone waves potentially reaching heights of 10 to 20 feet atop the storm surge.
This situation raises concerns that some coastal properties might experience significant damage or complete destruction.
Coastal resilience will be tested as multiple rounds of high surf could lead to washed-out roads and substantial beach erosion.
Although heavy rainfall is not anticipated, sustained winds may exceed tropical storm force (39 mph), with the likelihood of much stronger gusts.
In terms of the forecast, Erin is predicted to encounter conditions favorable for further intensification until Thursday, after which increasing wind shear is expected to initiate a gradual weakening.
Factors such as cooler ocean temperatures and drier air will start affecting the storm beginning Thursday.
As the week progresses, Erin is projected to transition into an extratropical cyclone by Sunday as it veers northeastward out to sea, positioned just south of Newfoundland, Canada.
In addition to Erin, there are two tropical waves being monitored for development.
One of these waves is located in the central Atlantic, advancing westward at around 20 mph (32 km/h) toward the Leeward Islands.
This particular wave is broad and disorganized, hindered by dry air impacting its northern edge, a phenomenon attributed to the Saharan Air Layer.
Model predictions indicate limited support for development in the early days, although there’s a stronger consensus for development later, possibly over the weekend.
The National Hurricane Center (NHC) has ascribed a 10% chance of formation within two days and a 60% chance within seven days to this disturbance.
The forthcoming storm will likely pass close to or a few hundred miles northeast of the Leeward Islands on Friday and Saturday before shifting northwest and north toward Bermuda, following a path influenced by Erin’s wake.
Meanwhile, the second tropical wave, identified as 99L and located just southwest of the Cabo Verde Islands, is moving west at roughly 15 mph (24 km/h).
Conditions for development appear moderately favorable, with sea surface temperatures around 28 degrees Celsius (82°F) and moderate wind shear present.
Recent satellite observations reveal that while 99L presents a decent area of heavy thunderstorms and mid-level atmospheric spin, it lacks a defined surface circulation.
Furthermore, an expansive region of dry air to the north, also connected to the Saharan Air Layer, is likely to stifle development.
Expectations indicate that wind shear will considerably surge, reaching 30-50 knots between Thursday and Saturday, thereby reducing the chances for further development.
In its latest Tropical Weather Outlook, the NHC has given 99L a 40% likelihood of becoming a more organized system over the next week.
image source from：yaleclimateconnections
