Hottest (avg)
#12 / 12
On the cooler side.
January in context
How it compares to the rest of the year in Boston.
Wettest (avg)
#5 / 12
Typical rainfall for the year.
Daylight Hours
#11 / 12
Shorter days.
Windiest (avg)
#1 / 12
The breeziest month of the year.
Highest UV
#11 / 12
UV is gentler than usual.
Most Humid
#9 / 12
Humidity stays close to the yearly norm.
Monthly climate breakdown
A detailed look at the typical climate conditions for January.
Thermal profile
Temperature
Typical daytime high
- Nighttime low
-
- Feels like (avg)
-
Light window
Sunshine
9.5 h
Average daylight
- UV index (max)
- 3
- Typical sun hours
- 07:08 - 16:38
Wet-day pattern
Rain & Snow
Typical rainfall
- Rainy days
- 12 days
- Cloud cover (avg)
- 58%
- Snowfall
-
Air feel
Humidity & Wind
69%
Average humidity
- Wind (avg)
-
- Wind (max gusts)
-
Historical daily baseline
Daily climate explorer
Pick a day to inspect the usual conditions through January in Boston. Based on a 30-year historical climate baseline, not a forecast.
Primary control
Select a day
Scroll to compare daily conditions. The summary updates with your selection.
Secondary context
Monthly trend
Median daytime highs across the month, with a softer low line.
Median temperatureMedian lowTypical range
Day 15 selected for January. Temperature 1.4°C.
Historical disruption baseline
Typical disruptions in January
Based on 30 years of historical data, these are the disruption patterns most likely to affect plans in January.
Cold High impact
Cold feels-like nights Measures: Cold feels-like nights (min <=5C). Observed about 100% of days (30.9 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
30.9 days / month
- Share of days
- ~100% of days
- Upper edge
- Up to ~-2°C (P95)
Why this matters
Cold feels-like nights are possible on ~31 days. Long outdoor blocks become harder to sustain, so layer up and keep a warm indoor fallback nearby.
Cold High impact
Freezing nights Measures: Freezing nights (min <=0C). Observed about 87% of days (27.0 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
27.0 days / month
- Share of days
- ~87% of days
- Upper edge
- Up to ~-1°C (P95)
Why this matters
Freezing nights are possible on ~27 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Cold High impact
Hard freeze nights Measures: Hard freeze nights (min <=-2C). Observed about 75% of days (23.2 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
23.2 days / month
- Share of days
- ~75% of days
- Upper edge
- Up to ~-3°C (P95)
Why this matters
Hard freeze conditions are possible on ~23 days. Long outdoor blocks become harder to sustain, so layer up and keep a warm indoor fallback nearby.
Snow High impact
Snow days Measures: Snow days (>=0.1mm snowfall). Observed about 30% of days (9.2 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
9.2 days / month
- Share of days
- ~30% of days
- Upper edge
- Up to ~11mm (P95)
Why this matters
Snowfall is possible on ~9 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Rain High impact
Rain disruption Measures: Likely rain disruption days. Observed about 19% of days (5.9 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
5.9 days / month
- Share of days
- ~19% of days
- Upper edge
- Up to ~31mm (P95)
Why this matters
Rain disruption risk appears on ~6 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Rain High impact
Washout risk Measures: Washout day risk. Observed about 19% of days (5.7 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
5.7 days / month
- Share of days
- ~19% of days
- Upper edge
- Up to ~31mm (P95)
Why this matters
Washout conditions are possible on ~6 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Show all disruptions (22 more)
Wind High impact
Strong gusts Measures: Strong gust days (>=60 km/h). Observed about 15% of days (4.7 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
4.7 days / month
- Share of days
- ~15% of days
- Upper edge
- Up to ~98km/h (P95)
Why this matters
Strong gusts are possible on ~5 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Rain High impact
Heavy rain days Measures: Heavy rain days (>=10mm). Observed about 12% of days (3.6 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
3.6 days / month
- Share of days
- ~12% of days
- Upper edge
- Up to ~34mm (P95)
Why this matters
Heavy rain is possible on ~4 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Wind High impact
Stormy conditions Measures: Storm-impact proxy days. Observed about 9% of days (2.6 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
2.6 days / month
- Share of days
- ~9% of days
- Upper edge
- Up to ~105km/h (P95)
Why this matters
Stormy conditions are possible on ~3 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Rain High impact
Washout run Measures: Multi-day washout runs. Observed about 1.2 days/month in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
1.2 days / month
- Share of days
- —
- Upper edge
- Up to ~34mm (P95)
Why this matters
Multi-day washout runs are possible on ~1 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Rain High impact
Very heavy rain Measures: Very heavy rain days (>=25mm). Observed about 4% of days (1.1 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
1.1 days / month
- Share of days
- ~4% of days
- Upper edge
- Up to ~46mm (P95)
Why this matters
Very heavy rain is possible on ~1 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Wind High impact
Severe gusts Measures: Severe gust days (>=80 km/h). Observed about 3% of days (0.9 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.9 days / month
- Share of days
- ~3% of days
- Upper edge
- Up to ~111km/h (P95)
Why this matters
Severe gusts are possible on ~1 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Visibility Moderate
Fog-likely signal Measures: Fog-likely visibility proxy. Observed about 8% of days (2.6 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
2.6 days / month
- Share of days
- ~8% of days
- Upper edge
- Up to ~98% (P95)
Why this matters
Fog-likely conditions are possible on ~3 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Cold Moderate
Wind chill risk Measures: Wind chill risk days. Observed about 8% of days (2.5 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
2.5 days / month
- Share of days
- ~8% of days
- Upper edge
- Up to ~-3°C (P95)
Why this matters
Wind chill risk is possible on ~3 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Cold Moderate
Cold snap run Measures: Cold snap runs (>=3 cold days). Observed about 2.0 days/month in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
2.0 days / month
- Share of days
- —
- Upper edge
- Up to ~9°C (P95)
Why this matters
Cold snap runs are possible on ~2 days. Long outdoor blocks become harder to sustain, so layer up and keep a warm indoor fallback nearby.
Cold Minor
Cold nights Measures: Cold nights (min <=5C). Observed about 99% of days (30.5 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
30.5 days / month
- Share of days
- ~99% of days
- Upper edge
- Up to ~2°C (P95)
Why this matters
Cold nights are possible on ~31 days. Long outdoor blocks become harder to sustain, so layer up and keep a warm indoor fallback nearby.
Cold Minor
Cold days Measures: Cold days (max <=10C). Observed about 92% of days (28.6 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
28.6 days / month
- Share of days
- ~92% of days
- Upper edge
- Up to ~8°C (P95)
Why this matters
Cold daytime conditions are possible on ~29 days. Long outdoor blocks become harder to sustain, so layer up and keep a warm indoor fallback nearby.
Wind Minor
Gusty days Measures: Gusty days (>=40 km/h). Observed about 56% of days (17.5 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
17.5 days / month
- Share of days
- ~56% of days
- Upper edge
- Up to ~80km/h (P95)
Why this matters
Gusty conditions are possible on ~17 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Cloud Minor
Cloudy days Measures: Cloudy days (cloud cover >=60%). Observed about 49% of days (15.3 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
15.3 days / month
- Share of days
- ~49% of days
- Upper edge
- Up to ~100% (P95)
Why this matters
Cloudy skies are possible on ~15 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Rain Minor
Wet days Measures: Wet days (>=0.1mm). Observed about 45% of days (14.1 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
14.1 days / month
- Share of days
- ~45% of days
- Upper edge
- Up to ~28mm (P95)
Why this matters
Measurable rain is possible on ~14 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Rain Minor
Rainy hours Measures: Rain-hours signal (>=3h rain). Observed about 37% of days (11.6 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
11.6 days / month
- Share of days
- ~37% of days
- Upper edge
- Up to ~22h (P95)
Why this matters
Several rainy hours are possible on ~12 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Cloud Minor
Mostly cloudy days Measures: Mostly cloudy days (cloud cover >=80%). Observed about 32% of days (9.9 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
9.9 days / month
- Share of days
- ~32% of days
- Upper edge
- Up to ~100% (P95)
Why this matters
Mostly cloudy skies are possible on ~10 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Humidity Minor
High humidity Measures: High humidity days (RH >=80%). Observed about 28% of days (8.7 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
8.7 days / month
- Share of days
- ~28% of days
- Upper edge
- Up to ~97% (P95)
Why this matters
High humidity is possible on ~9 days. Comfort and pace can drop quickly, so plan shorter outdoor blocks with air-conditioned backup stops.
Rain Minor
Wet most of day Measures: Wet-most-of-day signal (>=6h rain). Observed about 28% of days (8.6 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
8.6 days / month
- Share of days
- ~28% of days
- Upper edge
- Up to ~23h (P95)
Why this matters
Wet-most-of-day conditions are possible on ~9 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Cloud Minor
Overcast days Measures: Overcast days (cloud cover >=95%). Observed about 18% of days (5.5 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
5.5 days / month
- Share of days
- ~18% of days
- Upper edge
- Up to ~100% (P95)
Why this matters
Overcast skies are possible on ~5 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Wind Minor
Breezy days Measures: Breezy days (mean wind >=25 km/h). Observed about 9% of days (2.6 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
2.6 days / month
- Share of days
- ~9% of days
- Upper edge
- Up to ~33km/h (P95)
Why this matters
Breezy conditions are possible on ~3 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Other Minor
Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data Measures: Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data. Observed about 8% of days (2.6 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
2.6 days / month
- Share of days
- ~8% of days
- Upper edge
- Up to ~98 (P95)
Why this matters
Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data is possible on ~3 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Other Minor
Heavy snowfall (INACTIVE until snowfall_sum units confirmed; set threshold once units are verified) Measures: Heavy snowfall (INACTIVE until snowfall_sum units confirmed; set threshold once units are verified). Observed about 6% of days (1.7 days/month) in January. Historical risk signal only, not a day-by-day forecast.
Likely frequency
1.7 days / month
- Share of days
- ~6% of days
- Upper edge
- Up to ~23 (P95)
Why this matters
Heavy snowfall (INACTIVE until snowfall_sum units confirmed; set threshold once units are verified) is possible on ~2 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Travel planning FAQ
Frequently asked questions
Quick answers to the weather questions you ask the most.
Is January a good time to visit Boston?
Typical January days in Boston reach highs of 2°C (36°F) with nights around -7°C (19°F). It usually feels cold by day and very cold after dark. Overall, January sits in the middle of the Boston climate range.
What are temperatures like in January?
In January, you can usually expect highs of 2°C (36°F) and lows near -7°C (19°F). That means cold days and very cold nights, so pack layers you can add or remove.
How much does it rain in January?
Rainfall in January averages 100 mm (3.9 in) across roughly 12 days. Overall it is a quite rainy time of year, so a light rain jacket and waterproof shoes are very handy.
How many hours of daylight are there in January?
You can expect about 9 hours of daylight in January. Sunrise is typically around 07:08 and sunset near 16:38. Days are on the shorter side, so plan activities around limited daylight.
How strong is the sun in January?
UV levels are moderate (around 3); sunscreen and sunglasses are still a good idea.
Is it windy in January?
In January, average wind speeds are around 16 km/h (10 mph), with gusts on the windiest days reaching about 63 km/h (39 mph). On the ground, it is it is a notably windy place, and strong gusts are fairly common.