Earl's strongest winds to likely remain offshore
As of 11 a.m., Hurricane Earl was positioned 725 miles south southeast of Cape Hatteras and is moving northwest at 17 mph. Most computer models continue to indicate Earl will remain offshore though a couple have the center briefly passing over the North Carolina outer banks, where a hurricane warning is in effect. A hurricane watch covers the VA/MD/DE beaches. Earl's maximum sustained winds are 125 mph, down from 135 mph this yesterday -- making it a Category 3 storm.
Significant marine impacts are expected along many mid-Atlantic coastal locations with rough seas and dangerous rip currents. Despite its weakening, since Earl is a rather large hurricane, tropical-storm force wind gusts in rain squalls will likely brush the Outer Banks for several hours very early Friday morning. High seas up to 25 feet are possible just offshore of the Outer Banks (10-15 feet offshore VA/MD/DE beaches) with significant ocean overwash and sound-side flooding.
For the VA/MD/DE beaches, impacts will likely be less pronounced but not insignificant. Some showers and wind gusts to tropical-storm force are possible late Thursday night into Friday, with strong wave action, dangerous rip currents, and the possibility of minor coastal flooding. Though a hurricane watch has been issued for the VA/MD/DE beaches, hurricane force winds are not especially likely there unless the storm shifts west.
For the immediate D.C. metro region, the National Weather Service Office in Sterling, Va. summarizes the threat accordingly:
3AM EARLY FRIDAY MORNING UNTIL 3 PM FRIDAY AFTERNOON HURRICANE EARL WILL MAKE ITS CLOSEST PASS BY OUR AREA. HOW CLOSE IT COMES WILL DETERMINE OUR IMPACT. IF THE STORM STAYS ON ITS CURRENT FORECAST TRACK WELL OFFSHORE ... OUR IMPACTS WILL BE MINIMAL. HOWEVER IT SHOULD BE NOTED THAT THIS IS A VERY POWERFUL HURRICANE...ANY ADJUSTMENT OF THE FORECAST TRACK TO THE WEST OVER THE NEXT 48 HOURS WILL QUICKLY RAMP UP THE IMPACT TO OUR AREA. EVERYONE NEEDS TO STAY INFORMED ON THIS STORM AND READY TO REACT UNTIL IT PASSES. THIS IS ESPECIALLY TRUE FOR THOSE GOING TO THE BEACHES EARLY THIS HOLIDAY WEEKEND.
We concur with this assessment.
The track guidance, while remarkably consistent over the last couple of days given the characteristic uncertainty involved with forecasting a tropical cyclone's recurvature into the westerlies, continues to advertise a near miss. This is consistent with the theme our recent posts have presented; namely, that the core of Earl will likely remain offshore. The track models are clustered around the idea that Earl's eyewall will indeed recurve out to sea and miss the U.S. coastline, bypassing the eastern tip of the Outer Banks of North Carolina by roughly 100 miles at closest approach just after midnight Friday morning.
As Earl moves northward later Friday, the storm is still expected to remain off the Northeast U.S. Coast. The most recent hurricane tracks move Earl a little closer to coastal New England. Fortunately, cooler ocean waters and strengthening winds aloft should weaken Earl rapidly once it gets north of 40 degrees latitude (roughly the latitude of New York City). And though gusty winds of tropical storm strength and rain squalls may graze coastal New England late Friday, these conditions shouldn't last more than 6-8 hours given Earl's rapid movement away from the mainland.
During the past 18 hours, Earl's satellite presentation has exhibited progressively less symmetry. Looking more like a comma, and less like a circular buzzsaw, Earl appears to be battling with a hostile environment. Perhaps choking a bit on the extremely dry air surrounding its northern and western periphery (shown by the bronze shading in the given link), Earl's once coherent inner structure may be unraveling.
As mentioned in yesterday's update, the penetration of dry air into a tropical cyclone's primary circulation can indeed be damaging. Like an ice skater pulling her arms inward to spin faster, the intrusion of dry air can have the effect of pushing the arms back outward and slowing the rotation.
If that is indeed the case, and Earl is inhaling the arid surroundings, we may start to see a weakening trend that is irreversible. There is probably not enough time for it to reorganize and redevelop a resistance to the inward penetration of the Saharan Air Layer on its edges (this layer of desert-like air originated over the Saharan desert) before the ill effects of the wind shear associated with the incoming trough do their damage.
CWG's Jason Samenow contributed to this post