September 15, 2023 Outlook: Lee launching north, with impacts in New England and Canada tonight and Saturday

One-sentence summary

Hurricane Lee is en route to Atlantic Canada, a gigantic system, size-wise, and it will bring high-end tropical storm or hurricane impacts and surge to Atlantic Canada and Maine tomorrow.

Hurricane Lee: 85 mph, moving N 16 mph

What’s changed since Thursday evening?

Lee is beginning the process of transitioning to an extratropical system (more like a nor’easter than a hurricane), though the impacts will be the same regardless of designation.

Large, lumbering Lee lurching north toward Atlantic Canada. Expect conditions to gradually deteriorate on the coast of Massachusetts later today, New Hampshire and Maine later tonight, and Atlantic Canada on Saturday morning. (Weathernerds.org)

Lee’s forecast impacts

Let’s move south to north today.

First, Bermuda should see improving conditions through the day today as Lee pulls away. Given Lee’s size, it would be likely to assume a breeze will continue out of the southwest, probably at tropical storm force at times, diminishing later and returning to calmer conditions overnight.

Wind gusts near 60 mph will be possible on Cape Cod and Nantucket. Wind gusts drop off quickly away from the coast and Cape, though some higher terrain in central Mass north of Worcester could be a bit gusty. (NWS Boston)

For Massachusetts, winds will pick up out of the north-northeast through the day, reaching near tropical storm force this evening with gusts over 50 mph possible on the coast. Wind should peak around daybreak Saturday and then drop off through the day out of the northwest. Look for periods of rain, as well tonight and early Saturday, perhaps adding up to an inch or so on the Cape and Nantucket, less in Boston and Martha’s Vineyard.

Mostly “minor” level coastal flooding is expected from Lee across the Cape & Islands. (NWS Boston)

Storm surge of 1 to 3 feet will be possible for Nantucket, the Cape and up the Mass coast. Coastal flooding should be qualified mostly as “minor” in nature from this one.

In New Hampshire and southern Maine, winds should pick up this evening and peak Saturday morning through midday. Look for gusts of 45 to 55 mph or so on the coast, lower inland. Rain totals should be about an inch or so. Conditions will probably be a bit worse in southeast Massachusetts than in this area, due to the coastal geography. Surge will again be about 1 to 3 feet in this area, leading to minor coastal flooding.

In the White Mountains, the Maine lakes, Highlands, Kennebec Valley, and up through Katahdin, you can expect elevation dependent outcomes. Low elevations should see mostly 35 to 45 mph wind gusts with periods of rain. Higher peaks will probably see 60 to 80 mph gusts, with Mt. Washington, NH probably checking in around 100 to 125 mph.

The forecast for Mount Washington, NH on Saturday is just a touch breezy. (Mount Washington Observatory)

Rain totals will be in the 1 to 3 inch range, with lower-end amounts in New Hampshire and higher-end amounts in Maine.

For the Midcoast and Downeast Maine, you’ll likely see tropical storm conditions move in on Saturday morning and linger into Saturday night. Conditions should improve Sunday afternoon. The closer you get to Lubec and Eastport, the worse the conditions should be. Expect sustained winds near tropical storm force, around 40 mph or so, with gusts of 50 to 60 mph. Periods of heavy rain will lead to 2 or 3 inches in most places, with higher amounts as you get between Acadia and Eastport.

Wind gusts forecast for late morning Saturday should be close to hurricane force along parts of the Downeast coast and 40 to 60 mph elsewhere. (Pivotal Weather)

Surge of 1 to 3 feet (~1m) along the coast should lead to mostly minor flooding in Maine.

Moving into Canada, I don’t necessarily want to repeat everything I wrote yesterday, but I will repeat some because we took a deeper dive into Canadian impacts, and not a whole lot has changed since yesterday.

For coastal New Brunswick along the Bay of Fundy and western Nova Scotia along the Bay of Fundy, expect heavy rainfall, tropical storm conditions, and some very rough surf. I remain concerned about the Bay of Fundy and surge. There are some signs that the center may come in close to Saint John, NB which could allow a good bit of water to enter the bay. We will continue to watch this closely.

Digby into the Annapolis Valley in Nova Scotia saw a good bit of rain yesterday, and additional rain may front run things today. With another 1 to 3 inches (25 to 75 mm) or more, flash flooding may become an issue in parts of Nova Scotia.

Our impacts map based on Thursday’s Environment Canada update (not much has changed today). Still expecting significant surge in Nova Scotia and perhaps the Bay of Fundy.

Significant surge impacts with big waves will be likely in Nova Scotia along the Atlantic coast. Additionally, borderline hurricane conditions will be possible here. Probably the worst land impacts from Lee will happen on the Atlantic coast of Nova Scotia.

Eastern Nova Scotia will probably see nor’easter type conditions with tropical storm force gusts possible.

Prince Edward Island could see some rough surf inbound off the Gulf of St. Lawrence. Meanwhile, some of that rough surf could impact Nova Scotia and New Brunswick off the Northumberland Strait. But coastal impacts overall will be minor to moderate, with periods of rain and gusty winds.

Heavy rain will fall across central and northern New Brunswick, as well as the Gaspe Region of Quebec. Totals of 1 to 3 inches (25 to 75mm) are likely here.

Total rainfall in New Brunswick will be 2 to 4 in (50-100 mm), as it will be in western Nova Scotia. Amounts over 4 inches are possible in parts of Maine and maybe an isolated spot in New Brunswick up through the Gaspe Region. (NOAA)

Overall, for most folks, Lee will be an inconvenience and a nuisance storm. People along the Downeast Maine coast, Bay of Fundy, southwestern half of Nova Scotia, and much of New Brunswick should be taking Lee seriously and preparing for perhaps some more significant impacts. Fingers crossed for a positive outcome.

Elsewhere: Margot and Future Nigel

Margot remains a non-issue for us. Invest 97L is closer to developing this morning. The next name on the list is Nigel. This system is expected to avoid most land. However, it may be an item to watch for Bermuda eventually.

The track of Invest 97L (future Nigel, probably) brings it mostly northwest, perhaps broadly toward Bermuda next week. Otherwise, there should be a bit less heartburn with this system than we had with Lee. (Tomer Burg)

There may be yet another Cabo Verde system next week, which would likely follow Nigel out to sea. The Gulf remains quiet.

Thursday PM Lee Update: Lee basically on track for Atlantic Canada

One-sentence summary

Lee’s forecast is mostly unchanged today as we watch it forecast to bring significant surge to Nova Scotia and widespread wind and rain in New England and Canada.

Lee’s forecast is virtually unchanged today. (Tomer Burg)

Hurricane Lee: 85 mph, moving N 15 mph

What’s changed since this morning?

Tropical Storm Watches have been upgraded to Warnings for Nantucket and Martha’s Vineyard, as well as for the coast between Westport, MA and the Canadian border. Hurricane Watches remain in effect for a portion of Maine coast, a portion of the New Brunswick coast, and a portion of Nova Scotia. Tropical Storm Watches were expanded east a bit in Nova Scotia to Point Tupper.

The Storm Surge Watch for Cape Cod and the Islands was dropped, and the surge forecast lowered to 1 to 3 feet.

Lee’s wind field has grown to 345 miles from the center.

Lee’s impacts update & focus on New Hampshire, Maine, and Canada

Earlier today we talked about Massachusetts more in depth. Let’s focus farther up the coast for New Hampshire and Maine, as well as in Canada.

In general, winds are expected to be about 40 to 60 mph along and west of the track of Lee for eastern New England. Gusts of 60 to 80 mph will be possible just offshore of Maine. We could see higher gusts capable of bringing down trees in the Presidential Range or White Mountains in New Hampshire, as well as the higher peaks in the lakes region of Maine, Kennebec Valley, and Highlands. I suspect there will be some impressive wind gusts atop Mount Washington, as well as atop Katahdin.

Click to enlarge the forecast wind hazard map for Maine and New Hampshire. (NOAA)

Higher gusts will also be possible along the Midcoast and for the coast and mainland of Downeast Maine.

The rain forecast for Maine is a pretty uniform 1 to 3 inches for most of the state, with higher amounts basically south and east of Bangor, where Downeast could see 4 to 5 inches or so. Expect about an inch or less in New Hampshire, except along the coast or near the Maine border. Vermont will probably see clouds and some lighter rain. Expect heavy rain to impact New Brunswick as well as Nova Scotia too with 3 to 6 inches (75-150 mm).

Generally about 1 to 3 inches of rain is expected in Maine, with 4 to 5 inches for Downeast Maine. Lesser amounts are expected in New Hampshire and Vermont. (Pivotal Weather)

In terms of timing, look for tropical storm force winds to arrive Friday evening in southeast Massachusetts, just before sunrise Saturday on the North Shore of Mass and New Hampshire, Saturday morning for southern Maine and the Midcoast, and Saturday afternoon from Downeast into Atlantic Canada. Rain should spread southeast to northwest along the entire coast from Rhode Island through New Brunswick on Saturday morning after 12 AM or so. Nova Scotia may see rain begin late Saturday afternoon.

Note: The rain today in Nova Scotia, PEI, and New Brunswick may be a predecessor rain event (PRE) ahead of the hurricane. We’ve seen as much as 30 mm in spots from this rain, especially near Digby.

I remain concerned about surge impacts in both the Bay of Fundy and along the Nova Scotia coast in particular. The combination of high waves and high tides and surge will likely cause coastal flooding. Per Environment Canada, the most likely area for significant impacts is the Atlantic coast of mainland Nova Scotia. Rough seas and flooding issues are likely in the Bay of Fundy and perhaps to the north of Nova Scotia over the Gulf of St. Lawrence or Northumberland Strait.

A rough outline of impacts expected in Atlantic Canada based on Thursday afternoon’s update from Environment Canada. This map is an approximation and by no means official or perfect.

The second high tide cycle on Saturday, the one during the evening hours is likely to be the most severe one in Nova Scotia. Flooding is likely between Queens County and Halifax County. Water levels may be up over 3 feet (1m) above high tide levels, and a storm surge warning may be required for that time. I still want to watch the Bay of Fundy to see how much water gets funneled in toward the Isthmus of Chignecto.

We will have more details and info tomorrow morning at the usual time, around 8 AM ET.

Hurricane Lee continues on its path toward New England and Atlantic Canada

One-sentence summary

Hurricane Lee is on track to impact New England and Atlantic Canada this weekend, a significant storm capable of a serious storm surge and widespread winds.

Hurricane Lee’s forecast track continues to narrow some, with a path into the Bay of Fundy or Nova Scotia most likely at this point, although impacts will spread very, very far from the center. (Tomer Burg)

Hurricane Lee: 100 mph, moving N 9 mph

What’s changed since Wednesday evening?

A Hurricane Watch is now in effect for portions of extreme southwestern New Brunswick, as well as southwestern Nova Scotia. Tropical Storm Watches connect the two Hurricane Watches and also extend east across Nova Scotia past Halifax.

The rainfall forecast was nudged up a little for southeast Maine, southern New Brunswick, and southwest Nova Scotia.

Lee’s forecast track

For the most part, the track forecast is now baked in up to landfall. There may be some wobbles in terms of exactly where Lee ends up, but it’s narrowed to most likely between Eastport, ME and about Cape Sable Island.

Atlantic Canada surge impacts update

For Canada, we continue to worry most about surge, particularly with a storm that would come right into the Bay of Fundy, without making landfall on Nova Scotia. Essentially, large amounts of water would be funneled into the Bay. Saturday’s low tide in the bay is around 7:30 local time, with the subsequent high tide at 1:45 AM Sunday. That high tide may be the worst tide of the event for the Fundy coast of New Brunswick. Surge will extend far to the east of the center though, and a substantial surge may occur along much of Nova Scotia’s coast as Lee comes in.

The most significant waves will come into the southwest portion of Nova Scotia and perhaps into the Bay of Fundy, with considerable storm surge impacts on the Fundy coast of New Brunswick and in Nova Scotia (Weather Bell)

Again, it’s important to note that the most significant hazards will differ from those of Fiona last year, which tracked into eastern Nova Scotia. And the surge impact from this storm and the wind field of this storm will be broader and wider spread than most storms. This is a serious storm and should be treated as such.

Massachusetts outlook

Yesterday we noted that the one primary area of uncertainty may have been Cape Cod and the Islands, as the approach of Lee from the southeast would determine how much wind, rain, and surge we saw there. Lee is now expected to pass about 100 miles or so east of the Cape and Nantucket. This should offer up tropical storm force wind gusts, as well as at least some heavy rainfall to those areas.

The wind gust forecast for southern New England shows gusts of up to 60 mph possible on Cape Cod and the Islands, as well as south of Boston. (NWS Boston)

The strongest winds should stay offshore, and aside from the 2 to 4 foot surge and moderate coastal flooding, this will likely behave more like a strong nor’easter than anything for southern New England.

The tide forecast for Nantucket shows minor to perhaps moderate coastal flooding possible by Saturday. (NOAA)

Still, folks in these areas should continue to monitor forecast changes, particularly around the surge forecast to ensure that they’re up to speed on the latest. We’ll have a little more detail on the Maine and coastal New Hampshire outlook later this afternoon.

Lee’s wind and rainfall outlook

Changes to the wind and rainfall sections of our post yesterday were minimal. We are still expecting broadly the same outcomes from those regardless of whether Lee is a hurricane, tropical storm, or post-tropical. The rainfall forecast was nudged up a bit, however, with some areas now seeing more like 4 to 6 inches of rain.

Rain totals have been nudged up just a little across Maine, southern New Brunswick, and Nova Scotia with up over 4 inches possible in some of those areas. Flash flooding will be a concern. (NOAA)

We will have another post with the latest on any changes late this afternoon or evening.

Elsewhere in the tropics

Hurricane Margot has had a bit too much Sauvignon blanc and is basically doing loops southwest of the Azores. It remains no real threat to land for some time, though at some point I suppose it could approach the Azores.

Margot is confused. (NOAA NHC)

Invest 97L continues to look poised to soon develop and track out over the open ocean. Perhaps eventually Bermuda will need to watch this one, but that’s a long way off yet.

There are no other concerns beyond those systems.

Wednesday PM Lee Update: Watches issued for New England as Lee’s track gradually comes into focus

One-sentence summary

Hurricane Lee will pass west of Bermuda tomorrow and into Atlantic Canada or Downeast Maine on Saturday, bringing widespread wind and potentially severe storm surge impacts to portions of New England and (especially) Atlantic Canada.

The NHC forecast for Lee brings it toward the Bay of Fundy by Saturday evening. (Tomer Burg)

Hurricane Lee: 105 mph, moving NNW 10 mph

What’s changed since this morning?

Hurricane Watches have been posted for Downeast Maine from Stonington to the Canadian border, including Acadia National Park and Bar Harbor.

Tropical Storm Watches have been posted from Watch Hill, RI to Stonington, ME, including Cape Cod, Block Island, Martha’s Vineyard, and Nantucket.

Storm Surge Watches have been posted for Cape Cod Bay and Nantucket.

These watches will shift and be upgraded to warnings as Lee approaches closer.

Lee’s track forecast is coming into better agreement this afternoon, with an expected wobble toward but not into Massachusetts before an eventual landfall in either Downeast Maine, New Brunswick, or far western Nova Scotia.

Lee right now: Approaching Bermuda

Lee is still about 375 miles from Bermuda and will pass to the west later tomorrow. (Weathernerds.org)

Lee’s intensity is at 105 mph, making it a category 2 hurricane on the Saffir-Simpson Scale. However, because Lee’s hurricane-force winds extend out 115 miles and tropical-storm force winds extend out 265 miles, Lee is in rarefied air in terms of sizeable storms. It will likely bring tropical storm conditions to Bermuda tomorrow.

Lee’s forecast track: Getting closer to resolution

Yesterday saw a pretty severe lurch back toward the southern New England coast on modeling, and while that continues to a lesser extent today, we’re starting to narrow the track of Lee a bit. Lee will probably wobble back to the west as it approaches the latitude of Nantucket and southeast Massachusetts. But the mantra will be “bend, don’t break.” Lee’s track will bend west, but then it should wobble back northward or north-northeastward as it passes Cape Cod. In other words, it will get close but the core will probably stay east of Cape Cod and Boston.

Lee’s track will take it north-northeast, then bend it back west some near Cape Cod before taking it back off to the northeast toward Maine, New Brunswick, or western Nova Scotia. (Tomer Burg)

Lee’s impacts: Wind

Given the size of Lee’s wind field, the specific track matters very little for wind impacts from Lee (with one notable exception in Cape Cod). They will spread over a broad area extending from coastal Rhode Island through western Newfoundland. I mean, the expanse of likely tropical storm force winds from Lee is mammoth.

Tropical storm force winds are likely to impact the coast from Rhode Island through Maine (as well as some of the White Mountains in NH and interior Maine mountains). Most of Nova Scotia and southeast New Brunswick will see these winds as well. Hurricane-force winds can’t be ruled out on the coast of Maine or Nova Scotia. (Weather Bell)

The map above shows the forecast wind swath from today’s European operational model. Don’t focus on specifics here. I’ve tried to draw attention to how wide the wind field is with tropical storm force winds of 40 to 60 mph or stronger possible and likely. For portions of coastal Nova Scotia or even Downeast Maine, there may be the potential for hurricane-force wind gusts as well.

Even Cape Cod *may* get into the stronger winds depending on exactly how close Lee’s core gets to the coast on Saturday. Lee will still be a firm hurricane we think at that point, so if the core can approach the Cape, a period of 60 to 80 mph wind gusts will be possible. If Lee’s core stays far enough away, you probably will still gust to maybe 60 or so there, but the more damaging winds would stay offshore. Either way, we’re looking at widespread wind impacts from Lee, likely leading to numerous power outages, especially in Maine and Canada.

Lee’s impacts: Surge, an extremely serious concern in Nova Scotia, the Bay of Fundy, and portions of Maine

I am very, very concerned about the storm surge from Lee. Lee will behave far beyond what is “normal” or expected from a tropical storm or category 1 hurricane. For all intents and purposes, the equivalent of at least a category 2 or 3 surge will come ashore near and east of Lee’s track. Comparable analogs to Lee in terms of surge are Hurricane Ike in 2008 and Hurricane Sandy in 2012. Couple that by bringing Lee smack into the Bay of Fundy with the highest tides in the world and a new moon (with elevated tides already) and you have a potential problem brewing.

Lee’s surge in the U.S. may be worst in Cape Cod Bay, unless it makes landfall in Maine (in which case, the worst would be in Downeast Maine). The surge will be much worse than this in Canada. (NOAA NHC)

There is nuance, and the exact track will matter in terms of who sees how much surge. But for folks on Cape Cod and in Maine, you should prepare for a healthy coastal flooding/surge event. In Atlantic Canada on the coast, you should be preparing for serious flooding risks. In terms of analog tracks. Hurricane Ginny from 1963 may be the best fit here for Canada. I plotted Ginny, Juan, and Fiona on the map below just for comparison to Lee’s forecast track.

Lee’s forecast track plotted alongside Ginny, Juan, and Fiona. (NOAA)

Juan and Fiona were too far east to be considered adequate analogs to Lee in terms of surge or even wind impacts. Ginny was a little stronger than Lee will be, but I am assuming Lee’s wind field is larger.

Front page of the Bangor Daily News from October 30, 1963 after Hurricane Ginny passed by Maine and into Nova Scotia.

Whatever the case, I think it’s important to recognize the risk of serious surge here. Per the Canadian Hurricane Centre, the Bay of Fundy and coastal mainland Nova Scotia should see the worst surge impacts. We’ll provide more information once surge forecasts start populating.

In addition to surge, high waves and beach erosion will be an issue from the Southeast U.S. into Canada, along with rip currents.

Rain totals of 2 to 4 inches are generally expected from Lee as it moves into Canada. Isolated higher amounts will be possible, especially in higher terrain and/or portions of New Brunswick and Nova Scotia. (NOAA)

Lee’s impacts: Rain

Rain is not the most serious or concerning impact of Lee. However, there will be the potential for areas of heavy rain and flooding in portions of eastern New England, especially as those areas have seen a fair bit of rain lately. The heavy rain risk in Canada is primarily confined to Nova Scotia and New Brunswick. Rain should thin out some over Prince Edward Island.

We’ll stop there for this evening. Our next update will be as usual on Thursday morning.