Forest Grove weather in September
In September, Forest Grove sees average daytime highs of 74°F and overnight lows near 53°F, with 1.7 in of rain across 6 wet days and about 12.3 hours of daylight. It is the 3rd-warmest and 9th-wettest month of the year here.
Highs ease over the month, from about 78°F in the first days to 70°F by the end. The sky is clear or mostly clear about 48% of the time in September, and the air most often feels dry.
Daylight stretches from about 13 h 06 min at the start of September to 11 h 30 min by month's end. Set against the rest of the year, September is Forest Grove's 3rd-clearest and 9th-windiest month. For the whole year in context, see Forest Grove's year-round climate.
- Daytime high
- 74°
- 3rd warmest
- Overnight low
- 53°
- 10th coldest
- Rainfall
- 1.7 in
- 6 wet days
- Daylight
- 12 h 18 min
- 5:57 AM – 6:16 PM
- Cloud cover
- 42%
- 3rd clearest
- Wind
- 5 mph
- 9th windiest
- Solar energy
- 4.46 kWh/m²
- Travel score
- 7.7
- 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 September
Highs ease over the month, from about 78°F in the first days to 70°F by the end.
A typical September day in Forest Grove reaches about 74°F in the afternoon and slips back to 53°F overnight — a 21°F spread between the day's warmth and the night's chill. On most days the high lands between 64°F and 86°F. Set against its neighbours, September runs about 6°F cooler than August and about 12°F warmer than October.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°F) | 78 | 78 | 78 | 77 | 77 | 77 | 77 | 76 | 76 | 76 | 76 | 75 | 75 | 75 | 74 | 74 | 74 | 73 | 73 | 73 | 73 | 72 | 72 | 71 | 71 | 71 | 70 | 70 | 69 | 69 |
| Avg low (°F) | 55 | 55 | 55 | 55 | 55 | 55 | 54 | 54 | 54 | 54 | 54 | 54 | 53 | 53 | 53 | 53 | 53 | 53 | 52 | 52 | 52 | 52 | 51 | 51 | 51 | 51 | 51 | 50 | 50 | 50 |
| Avg high (°F) | Avg low (°F) | |
|---|---|---|
| 1 | 78 | 55 |
| 2 | 78 | 55 |
| 3 | 78 | 55 |
| 4 | 77 | 55 |
| 5 | 77 | 55 |
| 6 | 77 | 55 |
| 7 | 77 | 54 |
| 8 | 76 | 54 |
| 9 | 76 | 54 |
| 10 | 76 | 54 |
| 11 | 76 | 54 |
| 12 | 75 | 54 |
| 13 | 75 | 53 |
| 14 | 75 | 53 |
| 15 | 74 | 53 |
| 16 | 74 | 53 |
| 17 | 74 | 53 |
| 18 | 73 | 53 |
| 19 | 73 | 52 |
| 20 | 73 | 52 |
| 21 | 73 | 52 |
| 22 | 72 | 52 |
| 23 | 72 | 51 |
| 24 | 71 | 51 |
| 25 | 71 | 51 |
| 26 | 71 | 51 |
| 27 | 70 | 51 |
| 28 | 70 | 50 |
| 29 | 69 | 50 |
| 30 | 69 | 50 |
How September really feels in Forest Grove
Once humidity and wind are folded in, September averages 0 days that feel above 90°F and 0 that feel at or below 32°F — the comfort signal a plain temperature reading hides.
September sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.
Forest Grove weather by month
How September compares with the rest of the year at a glance. September is the 3rd-warmest and 9th-wettest month here — the current month is highlighted below.
| Month | High / Low (°F) | Rainfall (inches) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | 46° / 36° | 6.8 | 17.1 | 1.9 | 8.9 | 1.0 |
| Feb | 49° / 37° | 5.2 | 14.2 | 1.6 | 10.1 | 1.8 |
| Mar | 54° / 39° | 5.9 | 17.3 | 0.9 | 11.6 | 2.7 |
| Apr | 59° / 42° | 4.5 | 15.6 | 0.1 | 13.2 | 3.8 |
| May | 66° / 47° | 2.7 | 10.6 | 0 | 14.7 | 5.9 |
| Jun | 72° / 52° | 1.6 | 7.2 | 0 | 15.4 | 7.1 |
| Jul | 80° / 56° | 0.4 | 2.2 | 0 | 15.1 | 8.2 |
| Aug | 80° / 57° | 0.5 | 2.5 | 0 | 13.9 | 8.1 |
| Sep | 74° / 53° | 1.7 | 6 | 0 | 12.3 | 7.7 |
| Oct | 62° / 46° | 4.2 | 11.5 | 0 | 10.7 | 5.1 |
| Nov | 51° / 40° | 7.0 | 17.3 | 0.5 | 9.3 | 2.0 |
| Dec | 45° / 36° | 8.0 | 17.5 | 2.3 | 8.6 | 0.8 |
Cloud cover in September
The sky is clear or mostly clear about 48% of the time in September.
Beyond those clear spells, partly cloudy skies cover about 16% of September, with mostly cloudy or overcast conditions the remaining 37%.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Clearer (%) | 71 | 71 | 70 | 70 | 69 | 68 | 67 | 66 | 65 | 64 | 63 | 62 | 61 | 62 | 61 | 61 | 61 | 60 | 60 | 60 | 61 | 61 | 61 | 61 | 61 | 61 | 61 | 61 | 60 | 59 |
| Cloudier (%) | 29 | 29 | 30 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 38 | 39 | 39 | 39 | 40 | 40 | 40 | 39 | 39 | 39 | 39 | 39 | 39 | 39 | 39 | 40 | 41 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| 1 | 71 | 29 |
| 2 | 71 | 29 |
| 3 | 70 | 30 |
| 4 | 70 | 30 |
| 5 | 69 | 31 |
| 6 | 68 | 32 |
| 7 | 67 | 33 |
| 8 | 66 | 34 |
| 9 | 65 | 35 |
| 10 | 64 | 36 |
| 11 | 63 | 37 |
| 12 | 62 | 38 |
| 13 | 61 | 39 |
| 14 | 62 | 38 |
| 15 | 61 | 39 |
| 16 | 61 | 39 |
| 17 | 61 | 39 |
| 18 | 60 | 40 |
| 19 | 60 | 40 |
| 20 | 60 | 40 |
| 21 | 61 | 39 |
| 22 | 61 | 39 |
| 23 | 61 | 39 |
| 24 | 61 | 39 |
| 25 | 61 | 39 |
| 26 | 61 | 39 |
| 27 | 61 | 39 |
| 28 | 61 | 39 |
| 29 | 60 | 40 |
| 30 | 59 | 41 |
Chance of precipitation in September
Forest Grove gets around 1.7 in of rain over 6 wet days in September. The line is the day-by-day chance of measurable precipitation.
Day to day, the chance of measurable rain averages around 21% and peaks near 27% on the wettest days. The odds climb toward the end of the month.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain chance (%) | 13 | 14 | 14 | 15 | 15 | 16 | 17 | 18 | 18 | 19 | 20 | 21 | 21 | 21 | 22 | 22 | 22 | 22 | 22 | 22 | 23 | 23 | 23 | 23 | 23 | 24 | 24 | 25 | 26 | 27 |
| Rain chance (%) | |
|---|---|
| 1 | 13 |
| 2 | 14 |
| 3 | 14 |
| 4 | 15 |
| 5 | 15 |
| 6 | 16 |
| 7 | 17 |
| 8 | 18 |
| 9 | 18 |
| 10 | 19 |
| 11 | 20 |
| 12 | 21 |
| 13 | 21 |
| 14 | 21 |
| 15 | 22 |
| 16 | 22 |
| 17 | 22 |
| 18 | 22 |
| 19 | 22 |
| 20 | 22 |
| 21 | 23 |
| 22 | 23 |
| 23 | 23 |
| 24 | 23 |
| 25 | 23 |
| 26 | 24 |
| 27 | 24 |
| 28 | 25 |
| 29 | 26 |
| 30 | 27 |
Humidity in September
Most of September feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.
By dew point, September lands in the dry band about 87% of days. It rarely turns muggy — the humid and sticky bands barely register.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dry (%) | 85 | 85 | 85 | 85 | 85 | 86 | 86 | 86 | 86 | 85 | 85 | 85 | 85 | 85 | 86 | 86 | 85 | 85 | 86 | 86 | 87 | 87 | 88 | 88 | 89 | 90 | 90 | 91 | 91 | 92 |
| Comfortable (%) | 15 | 15 | 15 | 15 | 15 | 14 | 14 | 14 | 14 | 15 | 15 | 15 | 15 | 15 | 14 | 14 | 14 | 14 | 13 | 13 | 12 | 12 | 11 | 11 | 10 | 9 | 9 | 8 | 8 | 7 |
| Humid (%) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| Dry (%) | Comfortable (%) | Humid (%) | |
|---|---|---|---|
| 1 | 85 | 15 | 0 |
| 2 | 85 | 15 | 0 |
| 3 | 85 | 15 | 0 |
| 4 | 85 | 15 | 0 |
| 5 | 85 | 15 | 0 |
| 6 | 86 | 14 | 0 |
| 7 | 86 | 14 | 0 |
| 8 | 86 | 14 | 0 |
| 9 | 86 | 14 | 0 |
| 10 | 85 | 15 | 0 |
| 11 | 85 | 15 | 0 |
| 12 | 85 | 15 | 0 |
| 13 | 85 | 15 | 0 |
| 14 | 85 | 15 | 0 |
| 15 | 86 | 14 | 0 |
| 16 | 86 | 14 | 0 |
| 17 | 85 | 14 | 1 |
| 18 | 85 | 14 | 1 |
| 19 | 86 | 13 | 1 |
| 20 | 86 | 13 | 1 |
| 21 | 87 | 12 | 1 |
| 22 | 87 | 12 | 1 |
| 23 | 88 | 11 | 1 |
| 24 | 88 | 11 | 1 |
| 25 | 89 | 10 | 1 |
| 26 | 90 | 9 | 1 |
| 27 | 90 | 9 | 1 |
| 28 | 91 | 8 | 1 |
| 29 | 91 | 8 | 1 |
| 30 | 92 | 7 | 1 |
Wind in September
Winds average 5 mph in September.
Across September, 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.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wind speed (mph) | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 |
| Feels | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm |
| Wind speed (mph) | Feels | |
|---|---|---|
| 1 | 5 | calm |
| 2 | 5 | calm |
| 3 | 5 | calm |
| 4 | 5 | calm |
| 5 | 5 | calm |
| 6 | 5 | calm |
| 7 | 5 | calm |
| 8 | 5 | calm |
| 9 | 5 | calm |
| 10 | 5 | calm |
| 11 | 5 | calm |
| 12 | 5 | calm |
| 13 | 5 | calm |
| 14 | 5 | calm |
| 15 | 5 | calm |
| 16 | 5 | calm |
| 17 | 5 | calm |
| 18 | 5 | calm |
| 19 | 5 | calm |
| 20 | 5 | calm |
| 21 | 5 | calm |
| 22 | 5 | calm |
| 23 | 5 | calm |
| 24 | 5 | calm |
| 25 | 5 | calm |
| 26 | 5 | calm |
| 27 | 5 | calm |
| 28 | 5 | calm |
| 29 | 5 | calm |
| 30 | 5 | calm |
Sunrise & sunset in September
Daylight runs from about 13 h 06 min at the start of September to 11 h 30 min by month's end. The lit band spans sunrise to sunset each day.
Days shrink by about 96 minutes over September. Sunrise moves from 5:38 AM to 6:15 AM, and sunset from 6:46 PM to 5:48 PM.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight (h) | 13.1 | 13.1 | 13.0 | 13.0 | 12.9 | 12.9 | 12.8 | 12.7 | 12.7 | 12.6 | 12.6 | 12.5 | 12.5 | 12.4 | 12.4 | 12.3 | 12.3 | 12.2 | 12.2 | 12.1 | 12.0 | 12.0 | 11.9 | 11.9 | 11.8 | 11.8 | 11.7 | 11.7 | 11.6 | 11.5 |
| Sunrise (AM) | 5:38 | 5:40 | 5:41 | 5:42 | 5:43 | 5:45 | 5:46 | 5:47 | 5:48 | 5:50 | 5:51 | 5:52 | 5:54 | 5:55 | 5:56 | 5:57 | 5:59 | 6:00 | 6:01 | 6:02 | 6:04 | 6:05 | 6:06 | 6:08 | 6:09 | 6:10 | 6:11 | 6:13 | 6:14 | 6:15 |
| Sunset (PM) | 6:46 | 6:44 | 6:42 | 6:40 | 6:38 | 6:36 | 6:34 | 6:32 | 6:30 | 6:28 | 6:26 | 6:24 | 6:22 | 6:20 | 6:18 | 6:16 | 6:14 | 6:12 | 6:10 | 6:08 | 6:06 | 6:04 | 6:02 | 6:00 | 5:58 | 5:56 | 5:54 | 5:52 | 5:50 | 5:48 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| 1 | 13.1 | 5:38 | 6:46 |
| 2 | 13.1 | 5:40 | 6:44 |
| 3 | 13.0 | 5:41 | 6:42 |
| 4 | 13.0 | 5:42 | 6:40 |
| 5 | 12.9 | 5:43 | 6:38 |
| 6 | 12.9 | 5:45 | 6:36 |
| 7 | 12.8 | 5:46 | 6:34 |
| 8 | 12.7 | 5:47 | 6:32 |
| 9 | 12.7 | 5:48 | 6:30 |
| 10 | 12.6 | 5:50 | 6:28 |
| 11 | 12.6 | 5:51 | 6:26 |
| 12 | 12.5 | 5:52 | 6:24 |
| 13 | 12.5 | 5:54 | 6:22 |
| 14 | 12.4 | 5:55 | 6:20 |
| 15 | 12.4 | 5:56 | 6:18 |
| 16 | 12.3 | 5:57 | 6:16 |
| 17 | 12.3 | 5:59 | 6:14 |
| 18 | 12.2 | 6:00 | 6:12 |
| 19 | 12.2 | 6:01 | 6:10 |
| 20 | 12.1 | 6:02 | 6:08 |
| 21 | 12.0 | 6:04 | 6:06 |
| 22 | 12.0 | 6:05 | 6:04 |
| 23 | 11.9 | 6:06 | 6:02 |
| 24 | 11.9 | 6:08 | 6:00 |
| 25 | 11.8 | 6:09 | 5:58 |
| 26 | 11.8 | 6:10 | 5:56 |
| 27 | 11.7 | 6:11 | 5:54 |
| 28 | 11.7 | 6:13 | 5:52 |
| 29 | 11.6 | 6:14 | 5:50 |
| 30 | 11.5 | 6:15 | 5:48 |
Solar energy in September
Average shortwave solar energy reaching the ground each day in September, about 4.46 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 — September's 4.46 kWh/m² falls in the middle.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solar energy (kWh/m²) | 5.2 | 5.1 | 5.1 | 5.0 | 5.0 | 4.9 | 4.9 | 4.8 | 4.8 | 4.7 | 4.7 | 4.6 | 4.6 | 4.5 | 4.4 | 4.4 | 4.3 | 4.3 | 4.2 | 4.2 | 4.1 | 4.1 | 4.0 | 4.0 | 3.9 | 3.8 | 3.8 | 3.7 | 3.6 | 3.6 |
| Level | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| 1 | 5.2 | Bright |
| 2 | 5.1 | Bright |
| 3 | 5.1 | Bright |
| 4 | 5.0 | Bright |
| 5 | 5.0 | Bright |
| 6 | 4.9 | Bright |
| 7 | 4.9 | Bright |
| 8 | 4.8 | Bright |
| 9 | 4.8 | Bright |
| 10 | 4.7 | Bright |
| 11 | 4.7 | Bright |
| 12 | 4.6 | Bright |
| 13 | 4.6 | Bright |
| 14 | 4.5 | Bright |
| 15 | 4.4 | Bright |
| 16 | 4.4 | Bright |
| 17 | 4.3 | Bright |
| 18 | 4.3 | Bright |
| 19 | 4.2 | Bright |
| 20 | 4.2 | Bright |
| 21 | 4.1 | Bright |
| 22 | 4.1 | Bright |
| 23 | 4.0 | Bright |
| 24 | 4.0 | Moderate |
| 25 | 3.9 | Moderate |
| 26 | 3.8 | Moderate |
| 27 | 3.8 | Moderate |
| 28 | 3.7 | Moderate |
| 29 | 3.6 | Moderate |
| 30 | 3.6 | Moderate |
Hazard calendar for Forest Grove
None of Forest Grove's seasonal hazards are active in September. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do peak.
Forest Grove's rainy season runs October–April, when most of the year's rain falls.
Is September a good time to visit Forest Grove?
Our two travel scores rate September for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).
September is one of the better times to visit Forest Grove for general sightseeing.
What to pack for Forest Grove in September
From September's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In September, Forest Grove sees daytime highs around 74°F and nights near 53°F. Worth packing: light clothes. About 6 days see rain.
Sea temperature near Forest Grove in September
The nearest coast averages about 58°F in September — 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.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°F) | 50 | 49 | 50 | 51 | 54 | 57 | 58 | 59 | 58 | 55 | 53 | 50 |
| Comfort | Bracing | Bracing | Bracing | Bracing | Bracing | Bracing | Bracing | Bracing | Bracing | Bracing | Bracing | Bracing |
| Sea temperature (°F) | Comfort | |
|---|---|---|
| Jan | 50 | Bracing |
| Feb | 49 | Bracing |
| Mar | 50 | Bracing |
| Apr | 51 | Bracing |
| May | 54 | Bracing |
| Jun | 57 | Bracing |
| Jul | 58 | Bracing |
| Aug | 59 | Bracing |
| Sep | 58 | Bracing |
| Oct | 55 | Bracing |
| Nov | 53 | Bracing |
| Dec | 50 | Bracing |
UV index in Forest Grove in September
Clear-sky midday UV in September peaks around 5 — enough to warrant sun protection. 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.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 1 | 2 | 4 | 5 | 8 | 7 | 8 | 7 | 5 | 3 | 1 | 1 |
| Level | Low | Low | Moderate | High | Very high | High | Very high | High | Moderate | Moderate | Low | Low |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 1 | Low |
| Feb | 2 | Low |
| Mar | 4 | Moderate |
| Apr | 5 | High |
| May | 8 | Very high |
| Jun | 7 | High |
| Jul | 8 | Very high |
| Aug | 7 | High |
| Sep | 5 | Moderate |
| Oct | 3 | Moderate |
| Nov | 1 | Low |
| Dec | 1 | Low |
Air quality in Forest Grove in September
Average fine-particle pollution (PM2.5) through the year — so you can see where September 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).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 7 | 9 | 11 | 11 | 10 | 9 | 8 | 13 | 22 | 14 | 9 | 7 |
| Level | Good | Good | Good | Good | Good | Good | Good | Moderate | Moderate | Moderate | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 7 | Good |
| Feb | 9 | Good |
| Mar | 11 | Good |
| Apr | 11 | Good |
| May | 10 | Good |
| Jun | 9 | Good |
| Jul | 8 | Good |
| Aug | 13 | Moderate |
| Sep | 22 | Moderate |
| Oct | 14 | Moderate |
| Nov | 9 | Good |
| Dec | 7 | Good |
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.
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
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).