Guilford weather in January

In January, Guilford sees average daytime highs of 37°F and overnight lows near 28°F, with 3.9 in of precipitation across 9.9 wet days and about 9.4 hours of daylight. It is the 12th-warmest and 8th-wettest month of the year here.

Highs ease over the month, from about 39°F in the first days to 36°F by the end. The sky is clear or mostly clear about 33% of the time in January, and the air most often feels dry.

Daylight stretches from about 9 h 06 min at the start of January to 9 h 48 min by month's end. Set against the rest of the year, January is Guilford's 7th-clearest and 2nd-windiest month. For the whole year in context, see Guilford's year-round climate.

Daytime high
37°
12th warmest
Overnight low
28°
1st coldest
Precipitation
3.9 in
9.9 wet days
Daylight
9 h 18 min
7:20 AM – 4:40 PM
Cloud cover
59%
7th clearest
Wind
13 mph
2nd windiest
Solar energy
2.07 kWh/m²
Travel score
0.0
out of 10

Guilford is town in New Haven County, Connecticut, United States.

Founded
1639

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in January

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 39°F in the first days to 36°F by the end.

A typical January day in Guilford reaches about 37°F in the afternoon and slips back to 28°F overnight — a 9°F spread between the day's warmth and the night's chill. On most days the high lands between 26°F and 47°F. Set against its neighbours, January runs about 6°F cooler than December and on par with February.

10°20°30°40°50°151015202531
Avg high (°F)Avg low (°F)
14031
23931
33930
43930
53930
63830
73829
83829
93829
103829
113829
123728
133728
143728
153728
163727
173727
183727
193627
203627
213627
223627
233627
243627
253627
263627
273627
283627
293627
303627
313627

How January really feels in Guilford

Once humidity and wind are folded in, January averages 0 days that feel above 90°F and 31 that feel at or below 32°F — the comfort signal a plain temperature reading hides.

Days feeling ≥ 90°F
0
heat index over the day's high
Days feeling ≤ 32°F
31
wind chill below the day's low

The story in January is cold — wind chill drags the overnight "feels like" below the raw low.

Guilford weather by month

How January compares with the rest of the year at a glance. January is the 12th-warmest and 8th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan37° / 28°3.99.94.69.40.0
Feb38° / 28°3.58.94.210.30.0
Mar43° / 34°4.810.53.311.70.5
Apr52° / 43°4.211.10.513.12.7
May61° / 52°3.510.9014.35.0
Jun71° / 62°3.79.8014.96.6
Jul77° / 69°3.19014.77.0
Aug77° / 68°3.99.2013.77.1
Sep71° / 63°4.18.7012.36.9
Oct62° / 53°4.89.70.110.95.3
Nov52° / 43°4.09.30.59.72.7
Dec43° / 34°5.110.939.10.5

Cloud cover in January

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 33% of the time in January.

Beyond those clear spells, partly cloudy skies cover about 14% of January, with mostly cloudy or overcast conditions the remaining 53%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14951
24852
34852
44852
54852
64852
74852
84852
94654
104654
114654
124654
134753
144654
154654
164555
174654
184654
194654
204654
214654
224654
234753
244852
254852
264852
274951
284852
294852
304951
314951

Chance of precipitation in January

Any precipitationSnow

Guilford gets around 3.9 in of rain and snow over 9.9 wet days in January. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 32% and peaks near 35% on the wettest days, and about 5 days bring snow. The odds ease toward the end of the month.

0%10%20%30%40%50%151015202531
Rain chance (%)Snow chance (%)
13413
23414
33514
43515
53515
63515
73516
83516
93516
103516
113516
123516
133416
143415
153415
163315
173315
183214
193214
203114
213014
223014
232914
242914
252814
262814
272814
282814
292814
302814
312814

Humidity in January

DryComfortableHumidMuggyOppressiveMiserable

Most of January feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, January lands in the dry band about 100% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)
1100
2100
3100
4100
5100
6100
7100
8100
9100
10100
11100
12100
13100
14100
15100
16100
17100
18100
19100
20100
21100
22100
23100
24100
25100
26100
27100
28100
29100
30100
31100

Wind in January

Winds average 13 mph in January.

Across January, daily wind ranges from about 12 mph on the calmest days to 13 mph at its breeziest. It stays fairly steady from day to day.

05101520151015202531
Wind speed (mph)Feels
113breezy
213breezy
313breezy
413breezy
513breezy
613breezy
713breezy
813breezy
913breezy
1013breezy
1113breezy
1213breezy
1313breezy
1413breezy
1513breezy
1613breezy
1713breezy
1813breezy
1913breezy
2013breezy
2113breezy
2213breezy
2313breezy
2413breezy
2513breezy
2613breezy
2713breezy
2813breezy
2912breezy
3012breezy
3112breezy

Sunrise & sunset in January

DaylightNight

Daylight runs from about 9 h 06 min at the start of January to 9 h 48 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 42 minutes over January. Sunrise moves from 7:22 AM to 7:11 AM, and sunset from 4:26 PM to 4:57 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.17:224:26
29.17:224:27
39.17:224:27
49.17:224:28
59.17:224:29
69.17:224:30
79.17:224:31
89.27:224:32
99.27:224:33
109.27:224:34
119.27:224:35
129.27:214:36
139.37:214:37
149.37:214:38
159.37:204:39
169.37:204:40
179.47:204:41
189.47:194:42
199.47:194:43
209.47:184:44
219.57:184:45
229.57:174:47
239.57:174:48
249.57:164:49
259.67:154:50
269.67:154:51
279.67:144:52
289.77:134:54
299.77:124:55
309.77:124:56
319.87:114:57

Solar energy in January

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in January, about 2.07 kWh/m².

For context, solar energy here swings from a low near 1.72 kWh/m² to a high of 6.26 kWh/m² in June across the year — January's 2.07 kWh/m² sits near the bottom.

0123151015202531
Solar energy (kWh/m²)Level
11.8Dim
21.8Dim
31.8Dim
41.8Dim
51.8Dim
61.8Dim
71.9Dim
81.9Dim
91.9Dim
101.9Dim
111.9Dim
121.9Dim
132.0Dim
142.0Dim
152.0Moderate
162.0Moderate
172.1Moderate
182.1Moderate
192.1Moderate
202.2Moderate
212.2Moderate
222.2Moderate
232.3Moderate
242.3Moderate
252.3Moderate
262.4Moderate
272.4Moderate
282.4Moderate
292.5Moderate
302.5Moderate
312.5Moderate
Planning a trip in January

Hazard calendar for Guilford

In seasonPeak

None of Guilford's seasonal hazards are active in January. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do peak.

Guilford sits in the Atlantic hurricane belt; the season peaks August–October.

Atlantic hurricane
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is January a good time to visit Guilford?

Our two travel scores rate January for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

0.0
Sightseeing
11th-best month of the year
0.0
Beach & pool
9th-best month of the year

January is a weaker month for outdoor sightseeing in Guilford.

What to pack for Guilford in January

From January's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In January, Guilford sees daytime highs around 37°F and nights near 28°F. Pack a warm layer and a heavy coat. Worth having: rain gear and a windbreaker. About 10 days see rain.

a warm layera heavy coatrain geara windbreaker

Sea temperature near Guilford in January

The nearest coast averages about 40°F in January — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 12 mi away) is warmest in August at about 72°F and coldest in February near 36°F.

It's comfortable for a long swim from Jul 8 to Sep 25 — about 2.6 months when the water holds above 68°F.

30°40°50°60°70°80°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmcomfortable to swim
Sea temperature (°F)Comfort
Jan40Bracing
Feb36Bracing
Mar38Bracing
Apr44Bracing
May53Bracing
Jun63Cool
Jul70Refreshing
Aug72Refreshing
Sep70Refreshing
Oct64Cool
Nov55Bracing
Dec47Bracing

UV index in Guilford in January

LowModerateHighVery highExtreme

Clear-sky midday UV in January peaks around 2. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Guilford peaks around July 11 at about 8 (very high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near December 22 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 9 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highHighModerateLowJul 11UV 8Dec 22UV 1
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar5Moderate
Apr6High
May7Very high
Jun8Very high
Jul8Very high
Aug6High
Sep6High
Oct3Moderate
Nov2Moderate
Dec1Low

Air quality in Guilford in January

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where January falls, not just the annual average.

Air quality in Guilford is worst in July — around 20 µg/m³ PM2.5 (moderate), about 2.7× the cleanest month (November, 8 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1120 µg/m³Nov 188 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb13Moderate
Mar14Moderate
Apr16Moderate
May19Moderate
Jun20Moderate
Jul20Moderate
Aug17Moderate
Sep13Moderate
Oct9Good
Nov8Good
Dec9Good
Location & terrain

Where is Guilford?

Guilford sits at 41.3°N, 72.7°W, 46 ft above sea level, in United States. The nearest listed city is Madison, 4.3 mi away.

Topography around Guilford

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Guilford.

Within 2 miles, the terrain around Guilford has only modest variations in elevation — a maximum elevation change of 233 ft around an average of 69 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 764 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 1,680 ft.

The land around Guilford is covered by trees (69%) within 2 miles, trees (52%) and water (40%) within 10 miles, and trees (56%) and water (36%) within 50 miles.

2 miles
233 ft
10 miles
764 ft
50 miles
1,680 ft
treesgrasslandcroplandartificial surfaceswaterwetland
January weather nearby: Madison 4.3 mi · Branford 6.8 mi · East Haven 9.9 mi · North Haven 12 mi · New Haven 13 mi · Wallingford Center 13 mi · Hamden 14 mi · Wallingford 14 mi

United States travel facts

Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 100% of US
price level, 2025
GDP per capita
$90,027
2025
Happiness
6.8 / 10
World Happiness, 2025
Safe drinking water
98%
of population, 2024
Homicide rate
5.8
per 100k, 2023
Road deaths
12.7
per 100k/yr, 2019
Income group
High
World Bank
Religion
Protestant 47%unaffiliated 23%Roman Catholic 21%Jewish 2%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Guilford (41.289°, -72.6818°, elevation 46 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).