Boston Outdoor Adventure Weather Forecast for September 27-30, 2025

Today is September 27, 2025, and Boston's weather sets the stage for a mix of calm and layered skies with a practical edge for outdoor enthusiasts. Expect a mostly overcast sky with steady temperatures in the low to mid-70s Fahrenheit, winds around 8 mph with occasional gusts pushing up to 14 mph. High humidity around 65% lends a mild stickiness to the air but no immediate threat of rain for the evening.

By early morning on September 28, clouds hold their grip, thick and overcast through the day, with a brief window of light rain hitting around 9 AM, amounting to only light sprinkles (0.29 inches). Winds pick up a bit later, gusting close to 18 mph, shifting southward and then westward by afternoon, offering fresher air. Temperatures hover from high 60s at dawn climbing to low 80s by late afternoon. The evening unravels with clearer skies, dropping humidity to around 40%, and steady winds easing slightly.

Looking ahead to September 29, Boston will enjoy clear skies transitioning from mostly sunny midday to scattered clouds by sunset. The temps range from 60s in the morning to a comfortable upper 70s by afternoon, with lighter winds around 3-8 mph and low humidity making it ideal for most outdoor activities.

On September 30, the overcast cloud cover thickens again, bringing cooler readings mid-60s to low 70s, gusty winds from the northeast reaching 15 mph by evening and humidity rising to 60% or more. Visibility stays excellent with no precipitation expected.

Adventure Outlook:

For hikers and trail runners, September 28's morning light rain means slippery rocks and damp paths – proceed with caution especially on uneven terrain. Mid to late day offers recovering conditions with drying trails and a refreshing breeze to push you forward. The clear conditions on September 29 mark the sweet spot for crisp, invigorating outdoor activity—packed lunches, sunglasses, and layered clothing recommended. Meanwhile, September 30's windier, cooler day suits more vigorous pursuits like mountain biking or brisk walking, but caution is advised in exposed areas due to gusts.

Water sports enthusiasts should anticipate moderate winds that could make early morning calm waters more textured by afternoon, raising waves for adventurous kayakers or windsurfers but too rough for casual paddleboarding early on September 28.

Summary: Mild temperatures with intermittent clouds from late September's end, occasional light rain, and steady winds favor a range of adventures from clear-sky treks to moderate water activities. Overall, the stretch through September 27-30 promises accessible and diverse opportunities with sensible preparatory measures.

Weather Rating: 78/100

• The conditions are largely favorable for a broad spectrum of outdoor activities like hiking, running, cycling, and moderate water sports.
• Light morning showers on September 28 require caution for trail safety.
• Gusty winds toward the end of the period elevate difficulty for smaller watercraft and exposed outdoor activities.
• Ideal days: September 29 for hiking, trail running, and photography; September 30 for wind-friendly pursuits.

Dress in moisture-wicking layers, prepare for slick terrain in the mornings, and keep windbreaker gear handy for afternoon gusts. Boston’s early fall presents a well-rounded opportunity to engage dynamically with the outdoors under changing skies.