Forest Grove weather in January

In January, Forest Grove sees average daytime highs of 46°F and overnight lows near 36°F, with 6.8 in of precipitation across 17.1 wet days and about 8.9 hours of daylight. It is the 11th-warmest and 3rd-wettest month of the year here.

Highs climb over the month, from about 44°F in the first days to 48°F by the end. The sky is clear or mostly clear about 14% of the time in January, and the air most often feels dry.

Daylight stretches from about 8 h 36 min at the start of January to 9 h 24 min by month's end. Set against the rest of the year, January is Forest Grove's 11th-clearest and 7th-windiest month. For the whole year in context, see Forest Grove's year-round climate.

Daytime high
46°
11th warmest
Overnight low
36°
2nd coldest
Precipitation
6.8 in
17.1 wet days
Daylight
8 h 54 min
7:55 AM – 4:48 PM
Cloud cover
77%
11th clearest
Wind
5 mph
7th windiest
Solar energy
1.22 kWh/m²
Travel score
1.0
out of 10

Forest Grove is city in Oregon, USA.

Density
1,608/km²
people per km²
Founded
1840

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

Temperature in January

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 44°F in the first days to 48°F by the end.

A typical January day in Forest Grove reaches about 46°F in the afternoon and slips back to 36°F overnight — a 10°F spread between the day's warmth and the night's chill. On most days the high lands between 38°F and 53°F. Set against its neighbours, January runs on par with December and about 4°F cooler than February.

20°30°40°50°60°151015202531
Avg high (°F)Avg low (°F)
14435
24435
34435
44436
54436
64436
74536
84536
94536
104536
114536
124536
134536
144536
154636
164636
174636
184636
194637
204637
214637
224737
234737
244737
254737
264737
274737
284737
294737
304837
314837

How January really feels in Forest Grove

Once humidity and wind are folded in, January averages 0 days that feel above 90°F and 15 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
15
wind chill below the day's low

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

Forest Grove weather by month

How January compares with the rest of the year at a glance. January is the 11th-warmest and 3rd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan46° / 36°6.817.11.98.91.0
Feb49° / 37°5.214.21.610.11.8
Mar54° / 39°5.917.30.911.62.7
Apr59° / 42°4.515.60.113.23.8
May66° / 47°2.710.6014.75.9
Jun72° / 52°1.67.2015.47.1
Jul80° / 56°0.42.2015.18.2
Aug80° / 57°0.52.5013.98.1
Sep74° / 53°1.76012.37.7
Oct62° / 46°4.211.5010.75.1
Nov51° / 40°7.017.30.59.32.0
Dec45° / 36°8.017.52.38.60.8

Cloud cover in January

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 14% of the time in January.

Beyond those clear spells, partly cloudy skies cover about 9% of January, with mostly cloudy or overcast conditions the remaining 77%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
12377
22377
32377
42377
52377
62278
72278
82278
92278
102278
112278
122377
132377
142377
152476
162476
172476
182476
192476
202476
212476
222476
232476
242377
252377
262377
272377
282377
292377
302377
312377

Chance of precipitation in January

Any precipitationSnow

Forest Grove gets around 6.8 in of rain and snow over 17.1 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 55% and peaks near 57% on the wettest days, and about 2 days bring snow.

0%20%40%60%151015202531
Rain chance (%)Snow chance (%)
1559
2569
3569
4569
5569
6569
7569
8569
9578
10578
11578
12578
13567
14567
15566
16556
17556
18555
19545
20544
21544
22544
23544
24543
25543
26533
27533
28523
29523
30514
31514

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 5 mph in January.

Across January, daily wind ranges from about 5 mph on the calmest days to 5 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (mph)Feels
15calm
25calm
35calm
45calm
55calm
65calm
75calm
85calm
95calm
105calm
115calm
125calm
135calm
145calm
155calm
165calm
175calm
185calm
195calm
205calm
215calm
225calm
235calm
245calm
255calm
265calm
275calm
285calm
295calm
305calm
315calm

Sunrise & sunset in January

DaylightNight

Daylight runs from about 8 h 36 min at the start of January to 9 h 24 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 48 minutes over January. Sunrise moves from 7:59 AM to 7:44 AM, and sunset from 4:33 PM to 5:08 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
18.67:594:33
28.67:594:33
38.67:594:34
48.67:594:35
58.67:594:36
68.67:584:37
78.77:584:38
88.77:584:39
98.77:584:40
108.77:584:41
118.77:574:42
128.87:574:43
138.87:574:45
148.87:564:46
158.97:564:47
168.97:554:48
178.97:554:49
188.97:544:51
199.07:544:52
209.07:534:53
219.07:524:54
229.17:524:56
239.17:514:57
249.17:504:58
259.27:495:00
269.27:485:01
279.37:475:02
289.37:475:04
299.37:465:05
309.47:455:07
319.47:445:08

Solar energy in January

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in January, about 1.22 kWh/m².

For context, solar energy here swings from a low near 1.03 kWh/m² to a high of 6.77 kWh/m² in July across the year — January's 1.22 kWh/m² sits near the bottom.

00.511.522.5151015202531
Solar energy (kWh/m²)Level
11.1Dim
21.1Dim
31.1Dim
41.1Dim
51.1Dim
61.1Dim
71.1Dim
81.1Dim
91.1Dim
101.1Dim
111.1Dim
121.1Dim
131.2Dim
141.2Dim
151.2Dim
161.2Dim
171.2Dim
181.3Dim
191.3Dim
201.3Dim
211.3Dim
221.3Dim
231.4Dim
241.4Dim
251.4Dim
261.4Dim
271.5Dim
281.5Dim
291.5Dim
301.6Dim
311.6Dim
Planning a trip in January

Hazard calendar for Forest Grove

In seasonPeak

In January, Forest Grove sits inside its rainy season season. The full year is below, with each hazard's peak months called out.

Forest Grove's rainy season runs October–April, when most of the year's rain falls.

Rainy season
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is January a good time to visit Forest Grove?

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

1.0
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 Forest Grove.

What to pack for Forest Grove in January

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

In January, Forest Grove sees daytime highs around 46°F and nights near 36°F. Pack a warm layer and rain gear. Worth having: a heavy coat. About 17 days see rain.

a warm layerrain geara heavy coat

Sea temperature near Forest Grove in January

The nearest coast averages about 50°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 38 mi away) is warmest in August at about 59°F and coldest in February near 49°F.

The water stays below 68°F all year — cool enough that most swimmers want a wetsuit.

50°55°60°JanFebMarAprMayJunJulAugSepOctNovDecbracingcool
Sea temperature (°F)Comfort
Jan50Bracing
Feb49Bracing
Mar50Bracing
Apr51Bracing
May54Bracing
Jun57Bracing
Jul58Bracing
Aug59Bracing
Sep58Bracing
Oct55Bracing
Nov53Bracing
Dec50Bracing

UV index in Forest Grove in January

LowModerateHighVery highExtreme

Clear-sky midday UV in January peaks around 1. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Forest Grove peaks around July 17 at about 8 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 17 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateVery highVery highHighModerateLowJul 17UV 8Dec 17UV 1
UV index (midday)Level
Jan1Low
Feb2Low
Mar4Moderate
Apr5High
May8Very high
Jun7High
Jul8Very high
Aug7High
Sep5Moderate
Oct3Moderate
Nov1Low
Dec1Low

Air quality in Forest Grove 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 Forest Grove is worst in September — around 22 µg/m³ PM2.5 (moderate), about 3.0× the cleanest month (January, 7 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodSep 1621 µg/m³Jan 117 µg/m³
PM2.5 (µg/m³)Level
Jan7Good
Feb9Good
Mar11Good
Apr11Good
May10Good
Jun9Good
Jul8Good
Aug13Moderate
Sep22Moderate
Oct14Moderate
Nov9Good
Dec7Good
Location & terrain

Where is Forest Grove?

Forest Grove sits at 45.5°N, 123.1°W, 203 ft above sea level, in United States. The nearest listed city is Hillsboro, 5.6 mi away.

Topography around Forest Grove

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

Within 2 miles, the terrain around Forest Grove has only modest variations in elevation — a maximum elevation change of 331 ft around an average of 187 ft above sea level; within 10 miles, large variations in elevation — a maximum elevation change of 2,303 ft; within 50 miles, very significant variations in elevation — a maximum elevation change of 4,245 ft.

The land around Forest Grove is covered by trees (33%), grassland (24%) and cropland (24%) within 2 miles, trees (56%) and cropland (20%) within 10 miles, and trees (72%) within 50 miles.

2 miles
331 ft
10 miles
2,303 ft
50 miles
4,245 ft
treesgrasslandcroplandartificial surfaceswater
January weather nearby: Hillsboro 5.6 mi · Aloha 12 mi · Bethany 12 mi · Beaverton 15 mi · Newberg 17 mi · Sherwood 17 mi · Tigard 17 mi · Tualatin 19 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 Forest Grove (45.5198°, -123.1107°, elevation 203 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. 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).