Boston woke up in a gray blur Tuesday, with fog and mist hanging over Logan Airport and temperatures hovering near 68°F. Skies are expected to brighten through late morning, pushing the high toward about 80°F by Tuesday afternoon, July 28, 2026. A chance of showers and thunderstorms moves in after 11 a.m., but the real story starts after dark, when a steadier, heavier rain is set to take over late Tuesday night into Wednesday, July 29. Low-lying streets and neighborhoods with poor drainage are primed for ponding and brief street flooding once the heaviest bands roll through. If you have errands to run today, bring the rain gear and try to get them done before the overnight soaker sets in.
Timing And Totals
The bullseye for the worst of the rain arrives late Tuesday night and lingers through much of Wednesday, July 29, when daytime highs will likely stall in the low 70s. Widespread rainfall totals of 2–3 inches are on the table, with locally higher amounts possible, which bumps up the risk for localized street and flash flooding in the usual trouble spots. A Flood Watch and marine advisories are already posted for parts of the region, and timing can shift, so it is worth checking in with the latest alerts from the NWS Boston.
Today And Tonight
For Tuesday, July 28, expect a mix of clouds and sun, with a high near 80°F and a south wind running 5 to 16 mph. The chance of showers and thunderstorms climbs after 11 a.m., especially late in the day when the commute could get messy. Tonight turns mostly cloudy with a low around 66°F. A slight chance of showers develops after 2 a.m., and southeast winds will start to strengthen into the overnight hours as the main rain shield approaches.
Marine And Transit Impacts
Out on the water, increasing southeast to east winds and building seas will trigger Small Craft Advisories from late Tuesday into Wednesday, so mariners should think twice about heading out in smaller vessels during that stretch. On land, riders should brace for slower commutes during and after the heaviest downpours, when standing water and reduced visibility can bog things down. Check MBTA T-Alerts for any service advisories or delays.
How To Prepare
Plan on extra travel time, and do not drive through standing water, no matter how shallow it looks from behind the windshield. If you normally park in a known low spot, move your car to higher ground before the heaviest rain arrives. Anyone managing an outdoor event on Wednesday should have a solid backup plan to move indoors or reschedule, as brief but intense downpours could move through quickly and turn streets slick in a hurry.
