Updated
Alton Bay
Bay
Cool water — ease in carefully
Use cautionCool water — ease in carefully: water temperature is 66°F, cool enough to cause cold-water shock on a sudden entry.
- Water temperature is 66°F, cool enough to cause cold-water shock on a sudden entry.
- Heavy rain today can raise bacteria levels near outfalls and river mouths.
bay in Belknap County, New Hampshire, United States of America
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Cool water — ease in carefully
Use cautionCool water — ease in carefully: water temperature is 66°F, cool enough to cause cold-water shock on a sudden entry.
- Water temperature is 66°F, cool enough to cause cold-water shock on a sudden entry. — NOAA buoy SEIM1, as of Aug 23, 6:30 PM UTC
- Heavy rain today can raise bacteria levels near outfalls and river mouths.
No official beach-advisory feed for New Hampshire yet — follow posted signs and local guidance.
Live data from NOAA buoy SEIM1 (39.5 mi away), as of Aug 23, 6:30 PM UTC.
Weather at Alton Bay
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Frequently asked questions
- Where is Alton Bay?
- Alton Bay is a bay in New Hampshire.
- What is the water temperature at Alton Bay?
- As of August 23, 2026, the water temperature at Alton Bay in New Hampshire is 66°F (19°C), measured by NOAA buoy SEIM1, 39.5 miles away.
- Can you swim at Alton Bay?
- Cool water — ease in carefully: water temperature is 66°F, cool enough to cause cold-water shock on a sudden entry. Checked August 23, 2026.
- What amenities does Alton Bay have?
- Visitor-listed amenities at Alton Bay include camping-nearby.
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Best Times to Visit
- ›Weekday mornings (8–10 AM) are typically less crowded
- ›Check the forecast 2–3 days ahead for best planning
- ›Avoid holiday weekends for a quieter experience
Location & Contact
New Hampshire
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