New Hampshire sap flow forecast

The next several days for New Hampshire's sugaring country, read the way a sugarmaker reads them: how cold the night gets, how warm the afternoon gets, and whether that adds up to a run. The season here usually opens late February.

Sullivan County has 192,177 of New Hampshire's 566,187 taps (33.9%), the most in the state (2022 Census of Agriculture).

Forecast for Newport

Updated Sep 26, 5:43 AM EDT

It's the off-season. Sap needs freezing nights, and there are none in sight. New Hampshire's season usually opens around February 28 — 155 days from now.

No freeze-thaw days in the forecast

Blue = below 32°F · Amber = thaw · dashed line = freezing

SunSep 27
57°high
51°low
0h frozen
24h thawed
No freeze, no run
Low of 51°F — trees need a hard freeze to reload. No freeze, no run.
MonSep 28
57°high
51°low
0h frozen
24h thawed
No freeze, no run
Low of 51°F — trees need a hard freeze to reload. No freeze, no run.
TueSep 29
64°high
53°low
0h frozen
24h thawed
No freeze, no run
Low of 53°F — trees need a hard freeze to reload. No freeze, no run.
WedSep 30
70°high
51°low
0h frozen
24h thawed
No freeze, no run
Low of 51°F — trees need a hard freeze to reload. No freeze, no run.
ThuOct 1
72°high
53°low
0h frozen
24h thawed
No freeze, no run
Low of 53°F — trees need a hard freeze to reload. No freeze, no run.
FriOct 2
70°high
55°low
0h frozen
21h thawed
No freeze, no run
Low of 55°F — trees need a hard freeze to reload. No freeze, no run.

Data: National Weather Service. Verdicts use freeze-thaw thresholds from maple field research; your woods may run a little differently.

Coos County in the North Country ranks second with 92,173 taps (16.3%; 2022 Census of Agriculture).

Forecast for Lancaster

Updated Sep 26, 5:43 AM EDT

It's the off-season. Sap needs freezing nights, and there are none in sight. New Hampshire's season usually opens around February 28 — 155 days from now.

No freeze-thaw days in the forecast

Blue = below 32°F · Amber = thaw · dashed line = freezing

SunSep 27
60°high
49°low
0h frozen
24h thawed
No freeze, no run
Low of 49°F — trees need a hard freeze to reload. No freeze, no run.
MonSep 28
57°high
47°low
0h frozen
24h thawed
No freeze, no run
Low of 47°F — trees need a hard freeze to reload. No freeze, no run.
TueSep 29
62°high
47°low
0h frozen
24h thawed
No freeze, no run
Low of 47°F — trees need a hard freeze to reload. No freeze, no run.
WedSep 30
68°high
47°low
0h frozen
24h thawed
No freeze, no run
Low of 47°F — trees need a hard freeze to reload. No freeze, no run.
ThuOct 1
71°high
47°low
0h frozen
24h thawed
No freeze, no run
Low of 47°F — trees need a hard freeze to reload. No freeze, no run.
FriOct 2
68°high
49°low
0h frozen
21h thawed
No freeze, no run
Low of 49°F — trees need a hard freeze to reload. No freeze, no run.

Data: National Weather Service. Verdicts use freeze-thaw thresholds from maple field research; your woods may run a little differently.

Somewhere else in New Hampshire?

Your sugarbush, your forecast

Hourly temperatures for your exact spot, turned into a day-by-day sap-run outlook. US and Canada.

Planning ahead? Typical tapping dates for New Hampshire →

Data & method

National Weather Service API — NOAA National Weather Service
Sap flow in sugar maple: timing and weather drivers (Frontiers in Agronomy, 2025) — de Lima Santos et al.
Maple Sugaring Tips for Beginners and Backyard Maple Sugar Producers — UNH Extension
North American Maple Syrup Producers Manual, 2nd ed. (Bulletin 856) — The Ohio State University Extension

Never miss the first run

LuckySap can ping you the evening before a strong sap day, then keeps your collections, sugar readings, and boils in one season log. Free on iPhone.