Poor Brian’s Almanack: September 2026

September is the best month of the year on the New England coast, and most of the people who’d agree have already gone home. The water is within a degree or two of its August peak, the beaches empty out after Labor Day, and the fish that spent the summer up north start moving back down the coast. The days lose an hour and twenty-one minutes over the month. Sunset goes from 7:18 on the 1st to 6:27 on the 30th, and somewhere in the last week the nights get longer than the days.

The Month at a Glance

Sun times are for Boston, from the U.S. Naval Observatory . Moon phases fall on the 4th (last quarter), 10th (new), 18th (first quarter), and 26th (full, at 12:49 pm). The autumnal equinox is Tuesday the 22nd at 8:05 pm.

The Forecast

Expect ocean water still close to its summer best and the first night cold enough for a blanket in the same week: the week after Labor Day, a day or two after you’ve put the window unit in the basement. Expect a heat wave the week after that. September 10 is the statistical peak of the Atlantic hurricane season , so expect at least one forecast that puts a storm off the Carolinas and has everyone on the Cape checking the cone twice a day. Most of them turn out to sea. Plan for the one that doesn’t.

The Sky

The Harvest Moon. The full moon closest to the equinox is the Harvest Moon, and this year it’s full at 12:49 pm on Saturday the 26th. The name comes from what it does in the evening sky this time of year: the moon rises only about twenty minutes later each night instead of the usual fifty or so, so there’s moonlight right after sunset several nights in a row, which is what farmers bringing in a crop wanted. In Boston it rises at 6:00 pm on Friday the 25th, 6:21 on Saturday, and 6:44 on Sunday, each time right around sunset. Saturday is the night to watch it come up over the water. Find a spot facing east: Castle Island, the end of a Revere Beach jetty, or any beach on the outer Cape.

The equinox. The equinox is Tuesday the 22nd at 8:05 pm, but day and night aren’t actually equal that day. The atmosphere bends sunlight over the horizon, so the sun is up for a few minutes before it technically rises and after it technically sets. Boston still gets 12 hours and 9 minutes of daylight on the 22nd. The real crossover comes on the 26th, the first day with less than 12 hours of daylight.

Saturn. Saturn reaches opposition on October 4 , when it’s closest and brightest for the year, so by the end of September it’s rising around sunset and up all night. It’s the steady, yellowish point low in the east after dark, and it doesn’t twinkle. Its rings are tilted only about seven degrees toward us this year, so a small telescope shows them as a narrow ellipse rather than the wide-open rings in the pictures.

The Water

Water temperature. The Massachusetts Bay buoy  has started September between 64°F and 67°F in each of the last three years and ended it between 63°F and 65°F. That’s a degree or two below August, and dropping, but slowly. For swimming, the first half of the month is as good as August without the crowds. For diving, a 5mm wetsuit is plenty, and the summer crowds at the dive sites are gone after Labor Day.

Tides. September’s tides are mild. The biggest come at the end of the month: 11.1 feet at 1:34 pm on Tuesday the 29th and again at 2:19 pm on Wednesday the 30th, according to NOAA’s Boston station . That’s under a foot above an average high tide and more than a foot short of minor flooding, so it would take a real storm to put water in the streets. The bigger king tides come in October and November. For tidepooling, the best daylight low is Thursday the 10th at 5:15 pm, right at zero feet, with almost two hours of light left. Tuesday the 1st has one at 8:36 am.

The fall run. Striped bass start moving back down the coast this month, and the Cape Cod Canal’s peak usually runs from about September 12 to 26 , when the biggest fish come through feeding on the bait leaving the bays. False albacore, or albies, show up in the same weeks in Buzzards Bay, Vineyard Sound, and off the south side of the Cape. They’re fast, they’re unpredictable, and they’re the reason grown adults sprint down a jetty.

Sharks. White shark activity off the Outer Cape peaks from August into October , and the seals they’re following are still close to shore. Many town beaches stop having lifeguards after Labor Day, just as the water is warmest. If you’re swimming on the ocean side of the Outer Cape, stay in water where you can stand, and check the Atlantic White Shark Conservancy’s Sharktivity app for recent sightings first.

The Islands

The Derby. The 81st Martha’s Vineyard Striped Bass and Bluefish Derby  starts at 12:01 am on Sunday the 13th and runs five weeks, to October 17. It’s the island’s main event of the fall: weigh-ins at the Edgartown dock from 8 to 10 every morning and 7 to 9 every night, and a leaderboard half the island checks daily. Shore fishermen and boats both count, and false albacore are on the list as well as bass and blues.

Deer. Martha’s Vineyard, Nantucket, and the Elizabeth Islands get their own early deer season , September 21 to October 1, with primitive firearms or archery, because the deer population there has grown faster than the hunting has kept up. If you’re walking the island conservation land that week, wear something bright.

After Labor Day. On the islands the week after Labor Day is when the summer staff leaves, the ferry schedules thin out, and the restaurants start cutting days. The beaches are empty and the water is still warm. Nantucket’s family scallop season opens October 1, so if you want to scallop, start planning now.

The Woods

Hunting. The early season starts the first day of the month. Early Canada goose season  opens September 1, and bear season  opens Monday the 7th, now a single season through December 12 instead of three separate ones. Neither puts many people in the woods, but goose hunters are out at dawn on the fields and ponds, so expect shotguns at dawn on Labor Day weekend, Sunday excepted.

Mosquitoes. This is the worst of mosquito season for disease. On August 24 the state raised West Nile virus risk to high  in Boston, Brookline, Cambridge, Everett, Newton, Somerville, and Watertown, and by the end of August the state had five human cases , one of them a Boston man. Eastern equine encephalitis, rarer and more dangerous, turned up in mosquitoes  in Kingston in mid-August, raising the risk in Carver, Halifax, Kingston, and Plympton. The risk lasts until the first hard frost. Use repellent at dusk and dawn, wear long sleeves for evening events, and dump standing water around the house.

Hawks. The broad-winged hawks leave in the middle of the month, and they leave together. The population usually starts south between September 12 and 20 , riding thermals in spiraling groups called kettles, and on the right day, sunny with a northwest wind behind a cold front, a single hawk watch can count thousands. Wachusett Mountain in Princeton is the classic spot: its biggest days have topped 17,000 birds , and the volunteers counting at the summit are glad to point them out. Bring binoculars and a chair.

Mushrooms. Chicken of the woods comes in in September: big bright orange-and-yellow shelves on oaks and stumps, one of the easier finds for a beginner. Its dangerous neighbor is the jack-o’-lantern , also orange, also on wood, but with gills underneath instead of the chicken’s smooth, pored underside. Its gills glow faintly green in the dark, which is more interesting than eating it. Forage only where it’s allowed, which in Massachusetts doesn’t include state parks.

The Mountains

Foliage. Color starts at the top and comes down. By the usual pattern , the high country in northern New Hampshire and Vermont starts turning in the last week of September, and the White Mountains peak in early to mid October. Late September is when you get the first color without the October traffic.

The Presidentials. September is the best month for the big hikes above treeline: no bugs, cooler temperatures, clearer air. It’s also when the weather turns fastest. Mount Washington has usually had its first measurable snow in September , and the summit can go from fifty degrees to freezing rain in an afternoon. Carry a shell, a warm layer, gloves, and a headlamp, and turn around at the first sign of weather.

Passes. If you’re skiing this winter, September is when you decide. The cheapest Epic and Ikon prices end in the first week of October , and after that prices go up.

In Town

The Schooner Festival. The Gloucester Schooner Festival  runs Thursday the 3rd through Sunday the 6th. Working schooners and replicas from up and down the coast fill the harbor. The fireworks are Saturday the 5th at 9:15 pm , and Sunday brings the Parade of Sail through the harbor and then the races. The best view of the parade is from Stage Fort Park or the Dog Bar breakwater. The commuter rail runs from North Station to Gloucester in about an hour, which is the only sane way to get there on a festival weekend.

Labor Day. Monday the 7th. The last day of the summer schedule: lifeguards, ferries, and parking rules all change on Tuesday.

Cambridge Carnival. Cambridge Carnival International  fills University Park in Central Square on Sunday the 13th with a Caribbean-style costume parade, steel drums, and food. It’s free.

Fluff. Somerville’s What the Fluff? Festival  is Saturday the 19th, 1 to 5 pm in Union Square, where Marshmallow Fluff was invented in 1917. It’s what you’d guess from the name. The rain date is Sunday.

The Big E. The Big E , New England’s biggest fair, runs in West Springfield from Friday the 18th to October 4. Each of the six states has its own building on the Avenue of States, and the cream puffs are the reason most people go. It’s a long drive from Boston, so pick a weekday.

The Patriots. The home opener  is Sunday the 20th against the Steelers at 1 pm. Route 1 backs up for hours before kickoff, and the stadium train from South Station is the alternative to sitting in it.

The Garden

The lawn. UMass Extension  says the best time to reseed or renovate a lawn in Massachusetts is August 15 to September 15. The soil is still warm, the air is cooler, and the weeds are winding down. If the summer left bare patches, the first half of this month is the window. Keep the new seed damp until it’s up.

Apples. Most local orchards open for pick-your-own in the first or second week of September , and growers expect a strong crop this year. Go on a weekday if you can. On a sunny Saturday the line for cider doughnuts can take longer than the picking.

Seed garlic. Garlic goes in the ground in October, but the seed garlic to plant has to be ordered now, from a local grower or a seed company. Buy cloves grown for planting, not grocery-store garlic, which may be treated to stop it sprouting and is often a variety grown for warmer climates. UMass’s garlic guide  covers the rest.

The Home

Ragweed. Ragweed pollen peaks in mid-September , and it’s usually at its worst on dry, breezy mornings. If you’re allergic, this is the month to keep the windows shut in the morning and let the central air do the work. A MERV 11 or 13 filter in the air handler catches most of the pollen, and if you haven’t changed the filter since spring, now is the time.

Screens. With West Nile at high risk in most of Boston’s inner suburbs, an open window is only as good as the screen in it. Walk around the house, find the holes and the gaps around the window units, and patch them. A screen repair kit costs a few dollars, and it’s a better deal than a mosquito in the bedroom.

Heat. The heating season officially starts on the 15th: from then on, Massachusetts requires landlords who supply heat to keep rentals at 68°F by day and 64°F at night . Whether you’re the landlord or not, get the system serviced in September, before the first cold snap, when every HVAC company in the state is booked.

The storm kit. The peak of hurricane season is the 10th. Before then, check the flashlight batteries, charge the power banks, find the water jugs, and make sure you know where the main water shutoff is. Most Septembers it goes unused.

Poor Brian’s Almanack is a monthly almanac for coastal Massachusetts and the rest of New England.