Monthly outlook for Northumberland, NH: average high 74.6°, average low 55.7°. That is 1.5° above the climate normal for August. Precipitation is expected on 7 days (about 1.2 inches), against a normal of 6 days and 1.9 inches. The warmest day looks like 9 August (85.7°), the coolest 16 August (48.7°).
74.6°/55.7°
Average high / low
+1.5°
Above normal
7 / 6
Wet days / normal
1.2 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
9 August – 18 August
72.6°
72.8°
-0.1°
19 August – 28 August
77.9°
70.8°
+3.9°
29 August – 7 September
at normal
69°
—
August records over 66 years
91.4°2 August 1975All-time high
34°31 August 1965All-time low
Climate normals and records are computed from the nearest reference point — Berlin (14 mi).
Mon, 1082° / 60°0.04
82 °
Northumberland, Monday, 10 August
Light rain. High 82°, low 60°.
Pressure29.94 inHg
Wind6.3 mph SW
Humidity39%
Visibility6.2 mi
Dew point54°
Tue, 1178° / 57°0.04
78 °
Northumberland, Tuesday, 11 August
Light rain. High 78°, low 57°.
Pressure29.77 inHg
Wind8.9 mph NW
Humidity65%
Visibility6.2 mi
Dew point59°
Wed, 1276° / 54°0.02
76 °
Northumberland, Wednesday, 12 August
Light rain. High 76°, low 54°.
Pressure29.77 inHg
Wind4.9 mph W
Humidity41%
Visibility6.2 mi
Dew point50°
Thu, 1365° / 54°0.43
65 °
Northumberland, Thursday, 13 August
Rain. High 65°, low 54°.
Pressure29.62 inHg
Wind13.2 mph W
Humidity98%
Visibility—
Dew point59°
Fri, 1460° / 51°0.04
60 °
Northumberland, Friday, 14 August
Light rain. High 60°, low 51°.
Pressure29.83 inHg
Wind13 mph W
Humidity68%
Visibility—
Dew point44°
Sat, 1560° / 51°0.02
60 °
Northumberland, Saturday, 15 August
Light rain. High 60°, low 51°.
Pressure29.97 inHg
Wind10.1 mph W
Humidity72%
Visibility—
Dew point45°
Sun, 1675° / 49°0
75 °
Northumberland, Sunday, 16 August
Overcast. High 75°, low 49°.
Pressure30.09 inHg
Wind6.2 mph NW
Humidity41%
Visibility—
Dew point43°
Mon, 1774° / 56°0.02
74 °
Northumberland, Monday, 17 August
Light rain. High 74°, low 56°.
Pressure30.00 inHg
Wind6.6 mph W
Humidity42%
Visibility—
Dew point46°
Tue, 1871° / 52°0.07
71 °
Northumberland, Tuesday, 18 August
Light rain. High 71°, low 52°.
Pressure30.06 inHg
Wind7.2 mph NW
Humidity86%
Visibility—
Dew point57°
Wed, 1975° / 49°0
75 °
Northumberland, Wednesday, 19 August
Overcast. High 75°, low 49°.
Pressure30.15 inHg
Wind5.2 mph SW
Humidity48%
Visibility—
Dew point47°
Thu, 2083° / 55°0
83 °
Northumberland, Thursday, 20 August
Overcast. High 83°, low 55°.
Pressure30.03 inHg
Wind10.1 mph SW
Humidity59%
Visibility—
Dew point57°
Fri, 2184° / 65°0.42
84 °
Northumberland, Friday, 21 August
Rain. High 84°, low 65°.
Pressure29.83 inHg
Wind9 mph SW
Humidity88%
Visibility—
Dew point68°
Sat, 2279° / 58°0.07
79 °
Northumberland, Saturday, 22 August
Light rain. High 79°, low 58°.
Pressure29.94 inHg
Wind7.4 mph NW
Humidity79%
Visibility—
Dew point64°
Sun, 2378° / 55°0
78 °
Northumberland, Sunday, 23 August
Mostly clear. High 78°, low 55°.
Pressure29.97 inHg
Wind4.7 mph NW
Humidity49%
Visibility—
Dew point53°
Mon, 2468° / 62°0.01
68 °
Northumberland, Monday, 24 August
Light rain. High 68°, low 62°.
Pressure30.09 inHg
Wind3.2 mph E
Humidity76%
Visibility—
Dew point58°
From day 17 onward the outlook is built from 60-year climate statistics
Tue, 2571° / 53°0.13
71 °
Northumberland, Tuesday, 25 August
Climate normal for this date — 60-year average.
Average high71°
Average low53°
Average precipitation0.13 in
Chance of precipitation40%
Record high83° (2007)
Record low39° (1971)
Wed, 2672° / 54°0.05
72 °
Northumberland, Wednesday, 26 August
Climate normal for this date — 60-year average.
Average high72°
Average low54°
Average precipitation0.05 in
Chance of precipitation35%
Record high84° (1993)
Record low41° (1963)
Thu, 2771° / 55°0.09
71 °
Northumberland, Thursday, 27 August
Climate normal for this date — 60-year average.
Average high71°
Average low55°
Average precipitation0.09 in
Chance of precipitation42%
Record high83° (1993)
Record low41° (1989)
Fri, 2871° / 55°0.17
71 °
Northumberland, Friday, 28 August
Climate normal for this date — 60-year average.
Average high71°
Average low55°
Average precipitation0.17 in
Chance of precipitation40%
Record high84° (1977)
Record low43° (2025)
Sat, 2970° / 54°0.15
70 °
Northumberland, Saturday, 29 August
Climate normal for this date — 60-year average.
Average high70°
Average low54°
Average precipitation0.15 in
Chance of precipitation45%
Record high85° (1977)
Record low39° (1982)
Sun, 3070° / 53°0.1
70 °
Northumberland, Sunday, 30 August
Climate normal for this date — 60-year average.
Average high70°
Average low53°
Average precipitation0.1 in
Chance of precipitation40%
Record high83° (1991)
Record low39° (1965)
Mon, 3169° / 53°0.11
69 °
Northumberland, Monday, 31 August
Climate normal for this date — 60-year average.
Average high69°
Average low53°
Average precipitation0.11 in
Chance of precipitation33%
Record high82° (1973)
Record low34° (1965)
Tue, 0169° / 52°0.07
69 °
Northumberland, Tuesday, 1 September
Climate normal for this date — 60-year average.
Average high69°
Average low52°
Average precipitation0.07 in
Chance of precipitation27%
Record high84° (2010)
Record low40° (1967)
Wed, 0269° / 52°0.09
69 °
Northumberland, Wednesday, 2 September
Climate normal for this date — 60-year average.
Average high69°
Average low52°
Average precipitation0.09 in
Chance of precipitation30%
Record high84° (2010)
Record low39° (1991)
Thu, 0368° / 53°0.14
68 °
Northumberland, Thursday, 3 September
Climate normal for this date — 60-year average.
Average high68°
Average low53°
Average precipitation0.14 in
Chance of precipitation45%
Record high85° (2010)
Record low40° (1976)
Fri, 0469° / 53°0.1
69 °
Northumberland, Friday, 4 September
Climate normal for this date — 60-year average.
Average high69°
Average low53°
Average precipitation0.1 in
Chance of precipitation35%
Record high85° (1999)
Record low38° (1987)
Sat, 0569° / 52°0.09
69 °
Northumberland, Saturday, 5 September
Climate normal for this date — 60-year average.
Average high69°
Average low52°
Average precipitation0.09 in
Chance of precipitation27%
Record high82° (2014)
Record low38° (1963)
Sun, 0668° / 51°0.13
68 °
Northumberland, Sunday, 6 September
Climate normal for this date — 60-year average.
Average high68°
Average low51°
Average precipitation0.13 in
Chance of precipitation32%
Record high82° (1983)
Record low38° (2000)
Mon, 0769° / 51°0.06
69 °
Northumberland, Monday, 7 September
Climate normal for this date — 60-year average.
Average high69°
Average low51°
Average precipitation0.06 in
Chance of precipitation27%
Record high84° (2007)
Record low37° (1962)
About the monthly outlook
How accurate is a 30-day forecast?
The first 16 days come from weather models — reliable for the first 3–5 days and progressively less so after that. Days 17 through 30 for Northumberland, NH are built from the climate normal, the 60-year average, so they show typical weather for those dates rather than a specific forecast.
What does "above normal" mean?
We compare the forecast against the climate normal for those exact calendar days, computed from 60 years of observations. The deviation shows how much the coming month differs from a typical one.
Where do the 66-year records come from?
They are real temperature extremes recorded in Northumberland, NH since 1960: the highest and lowest reading for each calendar date, with the year it happened.
How often is it updated?
The forecast portion refreshes every hour; the climate portion is based on long-term data and stays stable.