The first fall nor'easter is aimed at the back half of this weekend, and the smart move is not to cancel your plans. It is to pick the ones built for it. Saturday and Sunday are expected to turn wet and windy, with the worst of it near the water, while Friday looks like the best window for anything outdoors. Here are six things happening across the Island between Friday, September 25 and Sunday, September 27, sorted roughly by how well each one can shrug off the weather.

A three-day music film marathon in Stony Brook

The Long Island Music and Entertainment Hall of Fame runs its Music Documentary Film Festival all weekend at 97 Main Street in Stony Brook, and it is the single most rain-proof plan on this list: three days of features, shorts and director conversations inside a museum you could happily wander anyway. The centerpiece for local pride is Saturday at 7 p.m., when The Long Island Underground Legends of Hip Hop screens with director Archie Snowden in the room for a conversation afterward, plus a live performance. The film digs into the suburban rap scene that grew up here in the shadow of the famous names, and seeing it a few feet from the hall's own hip-hop exhibits is the right setting. Tickets are sold per film through the hall's site.

The Ducks, three wins from a title, at home all weekend

The Long Island Ducks opened the Atlantic League Championship Series on the road this week and took the first game. The series now comes home: games at Fairfield Properties Ballpark in Central Islip are set for Friday at 6:35 p.m., Saturday at 6:35 p.m. and Sunday at 5:05 p.m., each played only if the series is still alive, against the Southern Maryland Blue Crabs. If the Ducks keep winning, a championship could be clinched on Long Island dirt this weekend. Friday is the safest bet weather-wise; if the storm arrives on schedule, watch the team's site and socials for any changes to Saturday and Sunday.

The Long Island Fair, 184 years old and only here once

The county fair for all of Long Island runs Friday through Sunday at Old Bethpage Village Restoration, 1303 Round Swamp Road, and this is its 184th year: agricultural exhibits, historic trades, livestock, live entertainment and midway food on the grounds of the restored village. A ticket is good for any one of the three days, which this year is a genuinely useful feature, because Friday is shaping up to be the day to use it. It is an outdoor fair, so if you are aiming for Saturday or Sunday, check the fair's social pages before you drive.

Gloria Estefan's story on the Argyle stage in Babylon

On Your Feet!, the musical built on the lives of Emilio and Gloria Estefan and the Miami Sound Machine, is playing the Argyle Theatre at 34 West Main Street in Babylon Village, with matinee and evening performances Saturday. The run continues through October 25, but a stormy Saturday is exactly what a warm theater full of conga rhythms is for, and downtown Babylon has enough dinner options within a two-block walk to make a full evening of it without ever really being outside.

Scares, indoors and out, in Bayville

Bayville Scream Park is in its 21st season, and this weekend it runs Friday evening from 8 to 11 p.m., Saturday from noon to 11 p.m. and Sunday from noon to 10 p.m. The haunted houses themselves are indoors, which makes this a better storm-weekend pick than it first sounds, though you will walk between them in whatever the sky is doing. Daytime Saturday and Sunday bring the Not-So-Scary lineup for younger kids, noon to 5 p.m., with a funhouse, mini golf and a pumpkin patch. Evening admission this weekend starts around $51 plus fees, and prices move with demand, so book the time slot rather than walking up.

A new place to play mahjong in Island Park

MJ Social, the mahjong club opening at 203A Long Beach Road in Island Park, welcomes its first players on Friday. It is a dedicated social club for a game having a genuine moment on Long Island: tables to book, sessions for newcomers who have never touched a tile, and a calendar that runs from afternoon into evening. As an inaugural-weekend plan it has two things going for it: it is entirely indoors, and you will be able to say you were there the first weekend. Seats are booked through the club's website.

The honest weather note

Forecasters expect the storm's rain and gusts to build Saturday and peak into Sunday, with the shoreline getting the roughest of it. That is not a reason to write off the weekend. It is a reason to put the fair and the ballpark on Friday, keep the film festival, the theater and the mahjong tiles in your back pocket for Saturday and Sunday, and check any outdoor event's own page before you get in the car. The Island does not close for rain. It just moves indoors.