Great Bay
Today’s Forecast:
Today’s Report:
Paddling
Use Caution for paddling. High near 78°F. Breezy winds (10 mph).
- Temp: Favorable conditions
- Rain: Favorable conditions
- Wind: Marginal weather factor
- Thunderstorm: Favorable conditions
Hiking
Excellent for hiking. High near 78°F. Light wind (10 mph).
- Temp: Marginal weather factor
- Rain: Favorable conditions
- Wind: Favorable conditions
- Thunderstorm: Favorable conditions
Outdoor Events / Activities
Excellent for outdoor events / activities. High near 78°F. Light wind (10 mph).
- Temp: Favorable conditions
- Rain: Favorable conditions
- Wind: Favorable conditions
- Thunderstorm: Favorable conditions
About Great Bay
Great Bay is a tidal estuary surrounded by wildlife refuge lands, river mouths, nature trails, research sites, and communities between Portsmouth and Exeter.
Make the Most of a Great Bay Day
Paddlers need tide and current knowledge in addition to a normal forecast. Mudflats, cold water, wind, fog, and sensitive wildlife areas can limit routes and landing choices.
Weather Tips for Great Bay
- Check coastal wind, fog, water temperature, tides or surf in addition to the inland temperature forecast.
- Wind, current, water temperature, waves, and lightning should guide water plans more than sunshine alone.
- After steady rain, favor paved paths or well-drained routes until natural surfaces recover.
- Spring mud, summer bugs, fall crowds, and winter ice can affect access even on a mild day.
Nearby Towns and Areas
This page can also be useful when planning outdoor time near:
- Great Bay National Wildlife Refuge
- Greenland
- Newmarket
- Durham
- Adams Point
- Lamprey River
- Squamscott River
- Stratham
Plan Around the Conditions
Use the forecast to choose the best version of a Great Bay day. Match elevation, wind, storms, water conditions, trail surfaces, road access, temperature, and daylight to the activity that gives your group the safest and most comfortable plan.
7-Day Forecast for Great Bay, NH
Great Bay Weather by Season
Winter
Winter at Great Bay brings snow, ice, wind chill, short daylight, and changing road access. Shaded trails, parking areas, and bridges can stay icy through mild spells. Check current facility and road status before departure.
Spring
Spring around Great Bay is mud season, with snowmelt, soft trails, lingering high-elevation ice, and rising waterways. Cold water remains a serious factor even when the air feels warm. Black flies often become noticeable from late spring into early summer.
Summer
Summer at Great Bay brings the warmest weather, humidity, mosquitoes, and afternoon thunderstorm potential. Morning commonly offers calmer water and a larger safety margin before storms. Carry water and use shade breaks during hot periods.
Fall
Fall is a popular season at Great Bay, with cooler air, changing foliage, and generally comfortable outdoor conditions. Busy foliage weekends can affect roads, parking, and waterfront towns. Cold nights, early ice, and rapidly shortening daylight return late in the season.
Key Climate Data Points
- Annual average temperature: generally around 47–49°F, based on the relevant summit or surrounding regional context.
- Annual snowfall: commonly 45–60 inches; elevation and year-to-year storm tracks cause substantial variation.
- Warmest months: July and August are normally warmest, although high terrain and water exposure stay cooler.
- Coolest months: January and February are typically coldest, with wind chill often more important than temperature alone.
- Wettest season: late fall and early winter are often wettest.
- Driest season: summer usually offers the longest fair-weather windows.
- Best outdoor window: late May through early October when tides, wind, and access cooperate.