Monthly outlook for Mendham, NJ: average high 65.8°, average low 48.4°. That is 1.6° above the climate normal for October. Precipitation is expected on 5 days (about 0.7 inches), against a normal of 5 days and 1.9 inches. The warmest day looks like 17 October (77.9°), the coolest 22 October (36.9°).
65.8°/48.4°
Average high / low
+1.6°
Above normal
5 / 5
Wet days / normal
0.7 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
8 October – 17 October
68.5°
63.9°
+2.6°
18 October – 27 October
61.2°
60.4°
+0.5°
28 October – 6 November
at normal
57.1°
—
October records over 66 years
88.7°2 October 2019All-time high
21.9°31 October 2011All-time low
Climate normals and records are computed from the nearest reference point — Morristown (6 mi).
Fri, 0970° / 42°0
70 °
Mendham, Friday, 9 October
Partly cloudy. High 70°, low 42°.
Pressure30.15 inHg
Wind10.9 mph W
Humidity40%
Visibility6.2 mi
Dew point41°
Sat, 1068° / 48°0
68 °
Mendham, Saturday, 10 October
Overcast. High 68°, low 48°.
Pressure30.50 inHg
Wind3.1 mph N
Humidity41%
Visibility6.2 mi
Dew point40°
Sun, 1165° / 52°0.05
65 °
Mendham, Sunday, 11 October
Light rain. High 65°, low 52°.
Pressure30.39 inHg
Wind7 mph SE
Humidity59%
Visibility6.2 mi
Dew point48°
Mon, 1266° / 59°0.32
66 °
Mendham, Monday, 12 October
Rain. High 66°, low 59°.
Pressure29.74 inHg
Wind12.3 mph E
Humidity93%
Visibility—
Dew point61°
Tue, 1375° / 53°0.2
75 °
Mendham, Tuesday, 13 October
Rain. High 75°, low 53°.
Pressure29.62 inHg
Wind14.7 mph NW
Humidity68%
Visibility—
Dew point56°
Wed, 1456° / 43°0
56 °
Mendham, Wednesday, 14 October
Partly cloudy. High 56°, low 43°.
Pressure29.97 inHg
Wind16.9 mph NW
Humidity49%
Visibility—
Dew point31°
Thu, 1561° / 40°0
61 °
Mendham, Thursday, 15 October
Mostly clear. High 61°, low 40°.
Pressure30.24 inHg
Wind6.6 mph SW
Humidity40%
Visibility—
Dew point29°
Fri, 1672° / 51°0
72 °
Mendham, Friday, 16 October
Clear. High 72°, low 51°.
Pressure30.24 inHg
Wind10 mph SW
Humidity61%
Visibility—
Dew point49°
Sat, 1778° / 56°0
78 °
Mendham, Saturday, 17 October
Clear. High 78°, low 56°.
Pressure30.21 inHg
Wind6.1 mph SW
Humidity57%
Visibility—
Dew point53°
Sun, 1870° / 57°0.11
70 °
Mendham, Sunday, 18 October
Light rain. High 70°, low 57°.
Pressure30.18 inHg
Wind8.3 mph S
Humidity74%
Visibility—
Dew point59°
Mon, 1961° / 53°0.06
61 °
Mendham, Monday, 19 October
Light rain. High 61°, low 53°.
Pressure30.06 inHg
Wind10.8 mph N
Humidity91%
Visibility—
Dew point56°
Tue, 2064° / 49°0
64 °
Mendham, Tuesday, 20 October
Clear. High 64°, low 49°.
Pressure30.09 inHg
Wind6.1 mph N
Humidity57%
Visibility—
Dew point43°
Wed, 2159° / 42°0
59 °
Mendham, Wednesday, 21 October
Overcast. High 59°, low 42°.
Pressure29.97 inHg
Wind11.6 mph NW
Humidity54%
Visibility—
Dew point41°
Thu, 2257° / 37°0
57 °
Mendham, Thursday, 22 October
Clear. High 57°, low 37°.
Pressure30.21 inHg
Wind6.5 mph N
Humidity45%
Visibility—
Dew point28°
Fri, 2356° / 42°0
56 °
Mendham, Friday, 23 October
Overcast. High 56°, low 42°.
Pressure30.27 inHg
Wind6.4 mph SE
Humidity76%
Visibility—
Dew point45°
From day 17 onward the outlook is built from 60-year climate statistics
Sat, 2460° / 45°0.13
60 °
Mendham, Saturday, 24 October
Climate normal for this date — 60-year average.
Average high60°
Average low45°
Average precipitation0.13 in
Chance of precipitation30%
Record high78° (2001)
Record low28° (1969)
Sun, 2560° / 46°0.11
60 °
Mendham, Sunday, 25 October
Climate normal for this date — 60-year average.
Average high60°
Average low46°
Average precipitation0.11 in
Chance of precipitation33%
Record high76° (1963)
Record low33° (1962)
Mon, 2659° / 45°0.18
59 °
Mendham, Monday, 26 October
Climate normal for this date — 60-year average.
Average high59°
Average low45°
Average precipitation0.18 in
Chance of precipitation37%
Record high77° (1963)
Record low34° (1962)
Tue, 2759° / 45°0.18
59 °
Mendham, Tuesday, 27 October
Climate normal for this date — 60-year average.
Average high59°
Average low45°
Average precipitation0.18 in
Chance of precipitation30%
Record high80° (1963)
Record low30° (1976)
Wed, 2858° / 44°0.16
58 °
Mendham, Wednesday, 28 October
Climate normal for this date — 60-year average.
Average high58°
Average low44°
Average precipitation0.16 in
Chance of precipitation32%
Record high78° (2023)
Record low29° (1976)
Thu, 2957° / 42°0.23
57 °
Mendham, Thursday, 29 October
Climate normal for this date — 60-year average.
Average high57°
Average low42°
Average precipitation0.23 in
Chance of precipitation28%
Record high73° (1984)
Record low30° (1965)
Fri, 3057° / 42°0.11
57 °
Mendham, Friday, 30 October
Climate normal for this date — 60-year average.
Average high57°
Average low42°
Average precipitation0.11 in
Chance of precipitation25%
Record high77° (2024)
Record low32° (2011)
Sat, 3157° / 42°0.06
57 °
Mendham, Saturday, 31 October
Climate normal for this date — 60-year average.
Average high57°
Average low42°
Average precipitation0.06 in
Chance of precipitation17%
Record high80° (2024)
Record low22° (2011)
Sun, 0158° / 44°0.09
58 °
Mendham, Sunday, 1 November
Climate normal for this date — 60-year average.
Average high58°
Average low44°
Average precipitation0.09 in
Chance of precipitation27%
Record high76° (2024)
Record low33° (1983)
Mon, 0258° / 44°0.11
58 °
Mendham, Monday, 2 November
Climate normal for this date — 60-year average.
Average high58°
Average low44°
Average precipitation0.11 in
Chance of precipitation32%
Record high75° (1982)
Record low30° (2002)
Tue, 0358° / 43°0.09
58 °
Mendham, Tuesday, 3 November
Climate normal for this date — 60-year average.
Average high58°
Average low43°
Average precipitation0.09 in
Chance of precipitation22%
Record high76° (2003)
Record low31° (2002)
Wed, 0456° / 42°0.06
56 °
Mendham, Wednesday, 4 November
Climate normal for this date — 60-year average.
Average high56°
Average low42°
Average precipitation0.06 in
Chance of precipitation22%
Record high72° (1987)
Record low31° (2006)
Thu, 0556° / 42°0.14
56 °
Mendham, Thursday, 5 November
Climate normal for this date — 60-year average.
Average high56°
Average low42°
Average precipitation0.14 in
Chance of precipitation28%
Record high74° (2022)
Record low31° (1983)
Fri, 0655° / 42°0.08
55 °
Mendham, Friday, 6 November
Climate normal for this date — 60-year average.
Average high55°
Average low42°
Average precipitation0.08 in
Chance of precipitation32%
Record high78° (2024)
Record low28° (2012)
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 Mendham, NJ 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 Mendham, NJ 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.