Hurricane Irene made landfall at Cape Lookout this morning bringing winds of 80 to 100 mph to the outer banks of North Carolina. Some gusts offshore have peaked over 110 mph. The storm continues to weaken with each update from the National Hurricane Center as it slowly drifts and spins inland across eastern NC. Further Weakening is likely but with a surface air pressure still at 953 mb…it is still a powerful storm with a large expansive wind field. This sort of air pressure is more typical of a category 2 hurricane.
The worst of the storm will occur from NC up through the mid-atlantic states. Moving NNE at 13 mph this will cross the outer banks and hug the coast all the way up through Long Island. As an upper level trough picks Irene up, it will help to push her just enough east to remain just off the coast of New Jersey and barely maintain her Catergory 1 strength. We will have to watch the land interaction, dry air entrainment and increasing vertical wind shear, and cooler sea surface temps, as this should cause Irene to weaken as the storm approaches New England tomorrow..the potential is there for most of us to see just tropical storm conditions on Sunday…but must prepare for hurricane force gusts which could do damage.
Still, as the storm starts to accelerate in it’s approach towards Long Island tomorrow morning…the combination of the forward movement with a low level circualtion creating winds upto 75 mph…the potential is there for this storm to create hurricane force winds at the coastline for a brief time as the storm makes landfall sometime by the midday through the afternoon. With an expected track through western Long Island up through the CT valley and into Northern New England by late afternoon and evening..the storm will undergo a transition, become extratropical,, becoming cold core with an expanding wind field but still providing tropical storm force winds across the north country tomorrow night.
Details & Timing:
A stalled front south of New England today. Clouds are advancing north today. The chance for a few scattered showers this afternoon and evening. Heavier rain will begin to track along this front after midnight as it tracks back into New England as a warm front. Conditions will be quickly deteriorate by dawn tomorrow with rain becoming heavy in tropical downpours and tropical storm force winds developing at the south coast. Rain will start out heavy south but have a tendency to back further west during the day…allowing for lighter rains in eastern New England…1-4″..locally 5″ near Worcester…with the heaviest of the rain on the western side of the track …which should be the CT river valley where there will be a widespread 5-8″ rain fall with pockets of 10 further west. This sort of heavy rain will give way to urban and river flooding west.
As mentioned above, the accelerating movement of the storm with Weak cat 1 winds pushing onshore during the midday through the afternoon will make for a brief period of damaging winds especially for coastal locations in southeastern New England. Winds out of the SSE could briefly gust to 70 to 80 mph in these spots…but there will be a longer duration of tropical storm force winds over a large area on the eastern side of the track across the rest of the region with winds ranging from 30-60 mph which will make it feel like a really wet and windy nor’easter. Still these kind of winds will be strong enough to topple trees and the potential for scattered power outages..especiall for areas seeing the stronger wind gusts. Winds could be strong on the back side as Irene pulls away Sunday night with gusts out of the west at 40-50.
Surf and Surge:
Swells are already starting to arrive at the south coast. Seas should build along the south coast to 4-7 ft swells by the end of the day. By 8 AM tomorrow we enter our first astro high tide along the south coast. By that time, seas will range from 8- 12 feet. Conditions will become very rough through the afternoon as aseas build to 20-30 feet off the coast. Low tide will building seas and increasing onshore winds means the tide will not recede much. If anything, by the evening tide of 8 PM as the storm pulls away…This wind and moon driven tide pushing the water and rough surf right into Buzzards Bay for an evening storm suge of 4-6 feet for most of Buzzards Bay…maybe a bit higher near the point of the Bay…depending upon how intense this storm is at landfall. The storm surge will have a damaging imapct of flooding for flood prone locations around the bay. Those of you who live along the eastern coast of MA…should escape with out much coast flooding…seas will be running high…there may be minor coastal flooding but nothing significant is expected. seas will quickly be subsiding into next week with the increasing sunshine and lightening winds.