It's Lee, Hi: Hurricane Lee Impacts Forecast for September 14th
Hurricane Lee will be a problem for coastal/eastern New England and Atlantic Canada over the weekend. These are the latest wind, surge, wave, and rain impacts expected.
Florida tropical threat synopsis: High seas, rip currents, and beach erosion from distant Hurricane Lee will continue on Florida’s Atlantic coast through the weekend. No non-Lee tropical threats to Florida (or the continental U.S.) over the next ten days.
Almanac: It’s Thursday, September 14th… day 105 of the 2023 hurricane season, 78 days to go. By total storm energy, the season is 52.9%, 62.7%, and 52.5% complete for the Atlantic, continental U.S., and Florida.
The 2023 Hurricane Season is about to claim a 💯, at least in objective terms. Later today, Lee and Margot will push the Atlantic over 100 units of Accumulated Cyclone Energy for the year. Seasons over 1950-2022 have averaged around 100 ACE for the whole year, so cracking the century mark in mid-September puts 2023 ahead of about 9 out of 10 years since 1950 to date.
Subjectively, I give the 2023 season so far a D-, the gentleman’s F.
Active Storms:
Hurricane Lee is accelerating north today, as expected, with forward motion at around 15 mph in the 11 a.m. NHC advisory. Maximum sustained winds are down to 90 mph (Category 1) as Lee crosses cooler waters churned up by previous storms, but the already expansive windfield continues to expand, with the region of tropical-storm-force winds now over 500 miles in diameter, and the region of hurricane-force winds still 175 miles in diameter.
With Lee now passing north of Florida’s latitude, coastal surf of 5-10’ from Florida into the Carolinas will continue through Sunday, along with rip currents and beach erosion. As seen above, Lee’s forecast track has nudged a little bit back east as anticipated since yesterday. The hurricane will pass around 200 miles east of Cape Cod Saturday morning, then cross into Nova Scotia or New Brunswick late Saturday and early Sunday as a Nor’easter-like non-tropical cyclone. I wouldn’t expect big changes to that forecast from here.
This means impacts are starting to come into better focus for New England and Atlantic Canada. First, in terms of wind, the slight track shift since yesterday is helpful for U.S. interests. The NWS Hurricane Threats and Impacts product for maximum wind gusts looks realistic, with low-end tropical-storm-force wind gusts in coastal Rhode Island, Massachusetts, and New Hampshire on Saturday. Wind gusts of 60 mph or more are likely only in coastal eastern Maine, Atlantic Canada, and perhaps (not shown on the NWS map) Cape Cod. Overall wind impacts in New England will be akin to a strong Nor’easter, although widespread tree damage is probable due to wet soils and leaves still being on the trees. Click the link under the track map above for the latest Tropical Storm/Hurricane Watches/Warnings.
Surge impacts will generally be fairly muted throughout most of the Northeast due to Lee’s strongest winds blowing from land-to-water, on the order of perhaps a couple of feet. This won’t be true in north-facing Cape Cod, where a Storm Surge Watch is in effect for the potential of 2-4’ of surge. Refer to the NHC’s high-resolution surge forecast map here for local details. Greatest surge danger is likely to be associated with ~1 pm Saturday high tide. Surge of 3-6’+ is also likely along and right of the track in Atlantic Canada; monitor statements from the Canadian Hurricane Center for details.
Relatedly, there is little change from the slight track shift to the extreme wave action that the hurricane will produce in the Gulf of Maine and Atlantic Canada this weekend. While the Outer Banks north to Rhode Island are likely to see 5-10’+ seas on Friday and Saturday while Cape Cod north into Maine will see 10-20’+ seas. Far eastern Maine and Atlantic Canada are still expected to see 20-40’ wave action on Saturday due to the massive fetch of southerly gales east of Lee’s circulation center.
Finally, rain and flooding impacts are likely to be significant in eastern Maine. With no further track changes, rainfall should reach west to eastern Massachusetts and New Hampshire on Saturday, where 0.5-2” storm totals are likely. This could well cause localized problems given heavy recent rainfall in New England. Heavier storm totals of 2-4” along with higher potential for flash flooding are expected in eastern Maine, western Nova Scotia, and New Brunswick.
So, bottom line, widespread wind and rain expected in eastern New England, though most impacts away from the immediate coast will be more limited. For Atlantic Canada, the combination of surge and extreme waves may result in major issues in western/central Nova Scotia and coastal New Brunswick, particularly in and along the funnel-shaped Bay of Fundy, already known for its legendary tides.
Hurricane Margot is still out in the nether regions of the Atlantic between Bermuda and an the Azores, with sustained winds of 80 mph. Margot will wheel around beneath a blocking ridge through the weekend and potential into late next week, but remains of no concern other than potentially to the Azores in 5-8 days.
Other disturbances in NHC outlook, with 2-/7-day NHC development odds: Invest 97L is in the process of forming a low-level center today halfway between the Lesser Antilles and West Africa, and the NHC has a 90% chance of development in the next 2 days. This wave is pretty much a lock to become Hurricane Nigel in the first half of next week as it tracks northwest towards Bermuda. It remains no threat to the U.S. or Atlantic Canada.
Elsewhere: No other features of note in the Atlantic today. Another tropical wave has a shot of developing in the eastern Atlantic in 6-10 days.
Next report: Daily bulletin out tomorrow afternoon for subscribers.