Climate and average weather in Forest Park
In Forest Park, the summers are humid, hot, wet, and partly cloudy and the winters are cool and partly cloudy.
Over the course of the year, the temperature in Forest Park typically varies from 36°F to 89°F, and is rarely below 21°F or above 95°F. July is the hottest month of the year, while January is the coldest.
Based on the travel score, the best times of year to visit Forest Park for warm-weather activities are from mid March to late May and mid September to mid November.
- Hottest
- Jul
- 89°
- Coldest
- Jan
- 36°
- Wettest
- Feb
- 4.3 in
- Driest
- May
- 2.9 in
- Rain / yr
- 44.3 in
- 123 wet days
- Daylight
- 9.8–14.2 h
- shortest–longest
- Elevation
- 988 ft
- 33.6°N
- Clearest
- Oct
- 46% cloud
Forest Park is city in Clayton County, Georgia, United States.
- Density
- 801/km²
- people per km²
Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.
Forest Park weather by month, at a glance
The whole year in one picture — sky, rain, humidity, temperature and travel score. Click any band to jump to its full chart.
Each stripe is one measure across the whole year, stacked so a single day reads top to bottom. The sky band runs overcast grey on top down to clear blue at the base — more blue means sunnier — followed by the rainfall curve, the humidity band, a temperature strip that tints each stretch of the year by how warm its average high is, and the travel-score line at the foot. Scan straight down any date to read that day across every measure at once; the score climbs highest around mid March to late May.
Temperature through the year
Daily average highs and lows in Forest Park, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.
The hot season lasts 4.4 months, from May 14 to September 24, with daily high temperatures above 80°F. The hottest month of the year in Forest Park is July, with an average high of 89°F and low of 72°F.
The cool season lasts 3.0 months, from November 27 to February 26, with daily high temperatures below 61°F. The coldest month of the year in Forest Park is January, with an average low of 36°F and high of 54°F.
Days typically run about 19°F warmer than nights year-round.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°F) | 54 | 58 | 65 | 73 | 81 | 87 | 89 | 88 | 83 | 74 | 64 | 56 |
| Avg low (°F) | 36 | 39 | 45 | 52 | 61 | 69 | 72 | 71 | 65 | 53 | 43 | 38 |
| Avg high (°F) | Avg low (°F) | |
|---|---|---|
| Jan | 54 | 36 |
| Feb | 58 | 39 |
| Mar | 65 | 45 |
| Apr | 73 | 52 |
| May | 81 | 61 |
| Jun | 87 | 69 |
| Jul | 89 | 72 |
| Aug | 88 | 71 |
| Sep | 83 | 65 |
| Oct | 74 | 53 |
| Nov | 64 | 43 |
| Dec | 56 | 38 |
How hot and cold Forest Park really feels
The felt-temperature range through the year — heat index on the day's high (summer humidity), wind chill on the night's low (winter wind). The dashed lines are the plain thermometer; the gap is how much hotter or colder it really feels.
On the hottest afternoons, once humidity is folded in, Forest Park feels like about 94°F (around July 25). About 70 days a year carry some heat stress, peaking in July.
On the coldest nights, wind chill pulls the feels-like down to about 29°F (around January 20), with roughly 56 freezing days a year (feels-like at or below 32°F), worst in January.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Feels-like high (°F) | 54 | 58 | 65 | 73 | 81 | 89 | 94 | 92 | 84 | 74 | 64 | 56 |
| Air high (°F) | 54 | 58 | 65 | 73 | 81 | 87 | 89 | 88 | 83 | 74 | 64 | 56 |
| Feels-like low (°F) | 29 | 33 | 41 | 52 | 61 | 69 | 72 | 71 | 65 | 53 | 39 | 33 |
| Air low (°F) | 36 | 39 | 45 | 52 | 61 | 69 | 72 | 71 | 65 | 53 | 43 | 38 |
| Feels-like high (°F) | Air high (°F) | Feels-like low (°F) | Air low (°F) | |
|---|---|---|---|---|
| Jan | 54 | 54 | 29 | 36 |
| Feb | 58 | 58 | 33 | 39 |
| Mar | 65 | 65 | 41 | 45 |
| Apr | 73 | 73 | 52 | 52 |
| May | 81 | 81 | 61 | 61 |
| Jun | 89 | 87 | 69 | 69 |
| Jul | 94 | 89 | 72 | 72 |
| Aug | 92 | 88 | 71 | 71 |
| Sep | 84 | 83 | 65 | 65 |
| Oct | 74 | 74 | 53 | 53 |
| Nov | 64 | 64 | 39 | 43 |
| Dec | 56 | 56 | 33 | 38 |
Average hourly temperature in Forest Park
A compact picture of the whole year, hour by hour: each column is a day, each row an hour, and the color is the modeled average temperature. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.
Read left to right for the day of the year and top to bottom for the hour of the day; the color is the modeled temperature, cool blues through to hot reds on the same scale as the other charts. A vertical slice is a single day's swing — coolest just before dawn, warmest in the mid-afternoon — while a horizontal slice follows one hour across the seasons. The darker overlay marks night and the lighter one the twilight around sunrise and sunset. Colors run warmest on July afternoons, near 89°F, and coldest before dawn in January, near 36°F.
Forest Park weather by month
Every month at a glance. Click a month for its detailed page.
| Month | High / Low (°F) | Rainfall (inches) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | 54° / 36° | 4.0 | 10.1 | 0.6 | 10 | 3.3 |
| Feb | 58° / 39° | 4.3 | 9.5 | 0.3 | 10.8 | 4.3 |
| Mar | 65° / 45° | 4.3 | 9.9 | 0.1 | 11.7 | 6.0 |
| Apr | 73° / 52° | 3.1 | 8.8 | 0 | 12.8 | 7.0 |
| May | 81° / 61° | 2.9 | 9.5 | 0 | 13.7 | 6.4 |
| Jun | 87° / 69° | 3.8 | 13.9 | 0 | 14.2 | 4.4 |
| Jul | 89° / 72° | 4.0 | 15.3 | 0 | 14 | 3.7 |
| Aug | 88° / 71° | 3.8 | 13 | 0 | 13.2 | 4.1 |
| Sep | 83° / 65° | 3.6 | 8.6 | 0 | 12.2 | 6.1 |
| Oct | 74° / 53° | 2.9 | 6.6 | 0 | 11.2 | 7.5 |
| Nov | 64° / 43° | 3.6 | 8.2 | 0 | 10.3 | 6.1 |
| Dec | 56° / 38° | 4.2 | 9.7 | 0.2 | 9.8 | 3.8 |
Chance of rain
How likely it is to rain on a typical day, and how that shifts across the wetter and drier seasons.
Forest Park gets about 44.3 in of precipitation a year. On a typical day the chance of rain is often wet, but that rises and falls sharply with the seasons.
The wetter season lasts 3.3 months, from around May 25 to Aug 31, peaking in July at about 51% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Oct 15.
February is the wettest month by volume, with 4.3 in over about 10 wet days; May is the driest, with 2.9 in.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain on a day (%) | 33 | 33 | 31 | 30 | 31 | 45 | 49 | 42 | 28 | 23 | 27 | 32 |
| Rain days | 10 | 10 | 10 | 9 | 10 | 14 | 15 | 13 | 9 | 7 | 8 | 10 |
| Rain on a day (%) | Rain days | |
|---|---|---|
| Jan | 33 | 10 |
| Feb | 33 | 10 |
| Mar | 31 | 10 |
| Apr | 30 | 9 |
| May | 31 | 10 |
| Jun | 45 | 14 |
| Jul | 49 | 15 |
| Aug | 42 | 13 |
| Sep | 28 | 9 |
| Oct | 23 | 7 |
| Nov | 27 | 8 |
| Dec | 32 | 10 |
Monthly rainfall
Over a full year, Forest Park collects about 44.3 in of rain across 123 wet days — roughly 3.7 in in an average month.
It doesn’t fall evenly. February is the wettest month with 4.3 in, while May is the driest at just 2.9 in. The three wettest months alone bring about 29% of the year’s total, and some of the cold-season precipitation falls as snow.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rainfall (in) | 4.0 | 4.3 | 4.3 | 3.1 | 2.9 | 3.8 | 4.0 | 3.8 | 3.6 | 2.9 | 3.6 | 4.2 |
| Rain days | 10 | 10 | 10 | 9 | 10 | 14 | 15 | 13 | 9 | 7 | 8 | 10 |
| Snow days | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Rainfall (in) | Rain days | Snow days | |
|---|---|---|---|
| Jan | 4.0 | 10 | 1 |
| Feb | 4.3 | 10 | 0 |
| Mar | 4.3 | 10 | 0 |
| Apr | 3.1 | 9 | 0 |
| May | 2.9 | 10 | 0 |
| Jun | 3.8 | 14 | 0 |
| Jul | 4.0 | 15 | 0 |
| Aug | 3.8 | 13 | 0 |
| Sep | 3.6 | 9 | 0 |
| Oct | 2.9 | 7 | 0 |
| Nov | 3.6 | 8 | 0 |
| Dec | 4.2 | 10 | 0 |
Clouds and sunshine
How often the daytime sky is clear, partly cloudy or overcast.
In Forest Park, the average share of the sky covered by clouds shows moderate seasonal variation over the course of the year.
The clearer part of the year begins around August 23 and lasts for 3.3 months, ending around November 30. The clearest month is October, when the sky is clear, mostly clear, or partly cloudy 59% of the time on average.
The cloudier part of the year begins around December 1 and lasts for 4.4 months, ending around April 12. The cloudiest month is December, when it is overcast or mostly cloudy 55% of the time.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Clearer (%) | 46 | 45 | 48 | 51 | 52 | 50 | 49 | 49 | 57 | 59 | 57 | 45 |
| Cloudier (%) | 54 | 55 | 52 | 49 | 48 | 50 | 51 | 51 | 43 | 41 | 43 | 55 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| Jan | 46 | 54 |
| Feb | 45 | 55 |
| Mar | 48 | 52 |
| Apr | 51 | 49 |
| May | 52 | 48 |
| Jun | 50 | 50 |
| Jul | 49 | 51 |
| Aug | 49 | 51 |
| Sep | 57 | 43 |
| Oct | 59 | 41 |
| Nov | 57 | 43 |
| Dec | 45 | 55 |
Daylight, sunrise and sunset
Hours of daylight through the year, with sunrise and sunset times.
The gold band is daylight — sunrise runs along its lower edge, sunset along the upper — so it widens toward summer and pinches toward winter, with night the dark area above and below. The longest day, around June 8, brings about 14 h 12 min of light; the shortest, around January 1, only 9 h 48 min — a swing of roughly 4 h 24 min.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight (h) | 10.0 | 10.8 | 11.7 | 12.8 | 13.7 | 14.2 | 14.0 | 13.2 | 12.2 | 11.2 | 10.3 | 9.8 |
| Sunrise (AM) | 7:47 | 7:29 | 6:55 | 6:13 | 5:42 | 5:31 | 5:42 | 6:04 | 6:26 | 6:48 | 7:16 | 7:40 |
| Sunset (PM) | 5:47 | 6:15 | 6:39 | 7:03 | 7:26 | 7:44 | 7:44 | 7:19 | 6:38 | 5:57 | 5:30 | 5:27 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| Jan | 10.0 | 7:47 | 5:47 |
| Feb | 10.8 | 7:29 | 6:15 |
| Mar | 11.7 | 6:55 | 6:39 |
| Apr | 12.8 | 6:13 | 7:03 |
| May | 13.7 | 5:42 | 7:26 |
| Jun | 14.2 | 5:31 | 7:44 |
| Jul | 14.0 | 5:42 | 7:44 |
| Aug | 13.2 | 6:04 | 7:19 |
| Sep | 12.2 | 6:26 | 6:38 |
| Oct | 11.2 | 6:48 | 5:57 |
| Nov | 10.3 | 7:16 | 5:30 |
| Dec | 9.8 | 7:40 | 5:27 |
Sunny days
How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.
Forest Park averages about 11 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 7 and 15 days.
The sunnier stretch runs 3.6 months, from around Sep 4 to Dec 21. The sunniest month is October, with roughly 14 sunny days (mixed).
The greyest month is July, down near 7 sunny days — about 49% fewer than the October peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sunny days | 11 | 9 | 11 | 11 | 10 | 8 | 7 | 9 | 11 | 14 | 13 | 11 |
| Sky | Mixed | Mixed | Mixed | Mixed | Mixed | Mixed | Gloomy | Mixed | Mixed | Mixed | Mixed | Mixed |
| Sunny days | Sky | |
|---|---|---|
| Jan | 11 | Mixed |
| Feb | 9 | Mixed |
| Mar | 11 | Mixed |
| Apr | 11 | Mixed |
| May | 10 | Mixed |
| Jun | 8 | Mixed |
| Jul | 7 | Gloomy |
| Aug | 9 | Mixed |
| Sep | 11 | Mixed |
| Oct | 14 | Mixed |
| Nov | 13 | Mixed |
| Dec | 11 | Mixed |
Humidity comfort
Share of days at each humidity comfort level, based on the dew point — the measure that tracks how muggy it actually feels.
Humidity comfort is graded by the dew point — the temperature at which the air would be fully saturated — because it tracks how muggy it actually feels far better than relative humidity does. A low dew point feels dry and crisp; a high one feels sticky and oppressive no matter the reading on a humidity gauge.
In Forest Park, how humid it feels changes dramatically over the year.
The more humid part of the year lasts 4.9 months, from around May 11 to October 7. The muggiest month is July, when the air feels humid, muggy or worse about 95% of the time.
The most comfortable stretch runs from around October 8 to May 10, and January is the most comfortable month — the air is dry or comfortable 99% of the time.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dry (%) | 93 | 92 | 84 | 67 | 32 | 5 | 0 | 1 | 15 | 54 | 84 | 91 |
| Comfortable (%) | 6 | 6 | 12 | 19 | 22 | 12 | 4 | 6 | 15 | 19 | 9 | 6 |
| Humid (%) | 1 | 2 | 3 | 14 | 26 | 20 | 8 | 13 | 24 | 16 | 5 | 2 |
| Muggy (%) | 0 | 0 | 0 | 1 | 19 | 40 | 39 | 37 | 32 | 10 | 2 | 1 |
| Oppressive (%) | 0 | 0 | 0 | 0 | 2 | 23 | 48 | 42 | 14 | 1 | 0 | 0 |
| Miserable (%) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 |
| Dry (%) | Comfortable (%) | Humid (%) | Muggy (%) | Oppressive (%) | Miserable (%) | |
|---|---|---|---|---|---|---|
| Jan | 93 | 6 | 1 | 0 | 0 | 0 |
| Feb | 92 | 6 | 2 | 0 | 0 | 0 |
| Mar | 84 | 12 | 3 | 0 | 0 | 0 |
| Apr | 67 | 19 | 14 | 1 | 0 | 0 |
| May | 32 | 22 | 26 | 19 | 2 | 0 |
| Jun | 5 | 12 | 20 | 40 | 23 | 0 |
| Jul | 0 | 4 | 8 | 39 | 48 | 0 |
| Aug | 1 | 6 | 13 | 37 | 42 | 1 |
| Sep | 15 | 15 | 24 | 32 | 14 | 0 |
| Oct | 54 | 19 | 16 | 10 | 1 | 0 |
| Nov | 84 | 9 | 5 | 2 | 0 | 0 |
| Dec | 91 | 6 | 2 | 1 | 0 | 0 |
Wind
Average wind speed through the year, banded into plain-language speed zones so a number reads as 'breezy' or 'calm' without knowing the scale.
This is the average sustained wind speed at the standard 10 metres above open ground — the steady flow a weather station reports, not the sharper gusts that come and go, which can run half again as fast. It's the number that says whether a place is generally breezy or calm.
Across the year, average wind speed in Forest Park is typically calm, near 6 mph, and varies moderately with the seasons.
The windier part of the year lasts 6.4 months, from around Oct 26 to May 8. The windiest month is March, averaging about 7 mph (light breeze).
The calmer part of the year runs from around May 9 to Oct 25, with August the calmest month at about 5 mph.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wind speed (mph) | 8 | 8 | 7 | 7 | 6 | 5 | 5 | 5 | 5 | 6 | 7 | 7 |
| Feels | light breeze | light breeze | light breeze | calm | calm | calm | calm | calm | calm | calm | calm | calm |
| Wind speed (mph) | Feels | |
|---|---|---|
| Jan | 8 | light breeze |
| Feb | 8 | light breeze |
| Mar | 7 | light breeze |
| Apr | 7 | calm |
| May | 6 | calm |
| Jun | 5 | calm |
| Jul | 5 | calm |
| Aug | 5 | calm |
| Sep | 5 | calm |
| Oct | 6 | calm |
| Nov | 7 | calm |
| Dec | 7 | calm |
Best time to visit Forest Park
To characterize how pleasant the weather is in Forest Park throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.
Around late March, Forest Park is still near the start of its best-weather window — great conditions with the peak-season crowds not yet at full swing.
Inferred from the travel-score curve; month-by-month visitor numbers are a planned addition.
The travel score favors clear, rainless days with daytime highs between 64°F and 82°F. Based on this score, the best times of year to visit Forest Park for general outdoor tourist activities run from mid March to late May and again from mid September to mid November, with a peak score in the third week of October.
The travel score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Travel score (0–10) | 3.3 | 4.3 | 6.0 | 7.0 | 6.4 | 4.4 | 3.7 | 4.1 | 6.1 | 7.4 | 6.0 | 3.9 |
| Rating | poor | fair | good | good | good | fair | fair | fair | good | good | good | fair |
| Travel score (0–10) | Rating | |
|---|---|---|
| Jan | 3.3 | poor |
| Feb | 4.3 | fair |
| Mar | 6.0 | good |
| Apr | 7.0 | good |
| May | 6.4 | good |
| Jun | 4.4 | fair |
| Jul | 3.7 | fair |
| Aug | 4.1 | fair |
| Sep | 6.1 | good |
| Oct | 7.4 | good |
| Nov | 6.0 | good |
| Dec | 3.9 | fair |
The beach/pool score favors clear, rainless days with daytime highs between 75°F and 93°F. Based on this score, the best times of year to visit Forest Park for hot-weather activities run from late April to late June and again from early August to mid October, with a peak score in the second week of September.
The beach/pool score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).
What to pack for Forest Park, by month
Month by month, what's worth putting in the bag — from the temperature range, rain chance, sun and wind. Tap a month for a quick packing note.
For a warm-season trip around July (highs near 89°F), the essentials are light clothes, rain gear and sun protection. In the cold season around January (highs near 54°F), pack a warm layer and rain gear.
In July, Forest Park sees daytime highs around 89°F and nights near 72°F. Pack light clothes and rain gear. Worth having: sun protection. About 15 days see rain.
UV index (midday) in Forest Park by month
Clear-sky midday UV index through the year, shaded by the WHO exposure levels — how much sun protection each month calls for.
Under clear skies, the midday UV index in Forest Park peaks around July 12 at about 10 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 19 at about 3 (moderate).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 11 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 3 | 5 | 5 | 7 | 8 | 9 | 10 | 9 | 7 | 5 | 4 | 3 |
| Level | Moderate | Moderate | High | Very high | Very high | Very high | Very high | Very high | Very high | High | Moderate | Moderate |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 3 | Moderate |
| Feb | 5 | Moderate |
| Mar | 5 | High |
| Apr | 7 | Very high |
| May | 8 | Very high |
| Jun | 9 | Very high |
| Jul | 10 | Very high |
| Aug | 9 | Very high |
| Sep | 7 | Very high |
| Oct | 5 | High |
| Nov | 4 | Moderate |
| Dec | 3 | Moderate |
Average hourly UV index in Forest Park
Modeled clear-sky UV for every hour of every day — when in the day sun protection actually matters.
The whole year hour by hour: each column is a day, each row an hour, and the color is the modeled clear-sky UV index — the midday peak scaled down as the sun sits lower in the sky. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.
UV falls off far faster than brightness as the sun drops, so even in July the burn window is concentrated in the middle of the day: about 8.5 hours a day reach index 3 (protection recommended), and 5.5 hours reach 6 or more. Mornings and late afternoons stay comparatively gentle year round.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV ≥ 3 (h/day) | 2.5 | 4.5 | 5.5 | 6.5 | 7.5 | 8 | 8.5 | 7.5 | 6.5 | 5 | 3.5 | 0 |
| UV ≥ 6 (h/day) | 0 | 0 | 0 | 3 | 4.5 | 5.5 | 5.5 | 4.5 | 3.5 | 0 | 0 | 0 |
| UV ≥ 3 (h/day) | UV ≥ 6 (h/day) | |
|---|---|---|
| Jan | 2.5 | 0 |
| Feb | 4.5 | 0 |
| Mar | 5.5 | 0 |
| Apr | 6.5 | 3 |
| May | 7.5 | 4.5 |
| Jun | 8 | 5.5 |
| Jul | 8.5 | 5.5 |
| Aug | 7.5 | 4.5 |
| Sep | 6.5 | 3.5 |
| Oct | 5 | 0 |
| Nov | 3.5 | 0 |
| Dec | 0 | 0 |
Air quality in Forest Park by month
Average fine-particle pollution (PM2.5) through the year — so you can see which months the air is worst, not just the yearly average.
Air quality in Forest Park is worst in July — around 21 µg/m³ PM2.5 (moderate), about 2.7× the cleanest month (January, 8 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) | 8 | 11 | 13 | 12 | 15 | 18 | 21 | 18 | 13 | 11 | 10 | 8 |
| Level | Good | Good | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Good | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 8 | Good |
| Feb | 11 | Good |
| Mar | 13 | Moderate |
| Apr | 12 | Moderate |
| May | 15 | Moderate |
| Jun | 18 | Moderate |
| Jul | 21 | Moderate |
| Aug | 18 | Moderate |
| Sep | 13 | Moderate |
| Oct | 11 | Good |
| Nov | 10 | Good |
| Dec | 8 | Good |
Growing season
Forest Park is mild enough that a frost-free day stays more likely than not even in midwinter. Nights are reliably above freezing from about March 15 to November 11 (242 days); outside that window a hard frost is an occasional risk.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Frost-free chance (%) | 63 | 75 | 91 | 99 | 100 | 100 | 100 | 100 | 100 | 99 | 88 | 73 |
| Frost nights | 31 | 28 | 14 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 17 | 31 |
| Frost-free chance (%) | Frost nights | |
|---|---|---|
| Jan | 63 | 31 |
| Feb | 75 | 28 |
| Mar | 91 | 14 |
| Apr | 99 | 0 |
| May | 100 | 0 |
| Jun | 100 | 0 |
| Jul | 100 | 0 |
| Aug | 100 | 0 |
| Sep | 100 | 0 |
| Oct | 99 | 0 |
| Nov | 88 | 17 |
| Dec | 73 | 31 |
Growing degree days
Growing degree days tally heat above 50°F: each day adds however many degrees its average temperature runs over that threshold, and cold days add nothing. Forest Park banks about 5,128 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around July.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Growing degree days (°F·days) | 0 | 5 | 158 | 386 | 652 | 827 | 942 | 914 | 718 | 422 | 103 | 0 |
| Growing degree days (°F·days) | |
|---|---|
| Jan | 0 |
| Feb | 5 |
| Mar | 158 |
| Apr | 386 |
| May | 652 |
| Jun | 827 |
| Jul | 942 |
| Aug | 914 |
| Sep | 718 |
| Oct | 422 |
| Nov | 103 |
| Dec | 0 |
Solar energy
Average daily shortwave solar energy reaching the ground, banded into brightness zones so the number means something at a glance.
Solar energy is how much sunlight actually reaches the ground each day, measured in kilowatt-hours per square metre (kWh/m²) — the combined effect of how long the sun is up, how high it climbs, and how much cloud gets in the way. It's the raw fuel a solar panel has to work with: for scale, 1 kWh/m² a day is dim and wintry, while 7+ is desert-bright.
Forest Park receives about 4.5 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 2.3 and 6.1 kWh/m².
The brighter stretch of the year lasts 6.3 months, from around Mar 15 to Sep 21. The brightest month is May, averaging about 6.1 kWh/m² (intense).
The dimmest month is December, down near 2.4 kWh/m² — roughly 61% less than the May peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solar energy (kWh/m²) | 2.7 | 3.3 | 4.5 | 5.6 | 6.1 | 6.1 | 5.9 | 5.4 | 4.6 | 3.9 | 3.0 | 2.4 |
| Level | Moderate | Moderate | Bright | Bright | Intense | Intense | Bright | Bright | Bright | Moderate | Moderate | Moderate |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| Jan | 2.7 | Moderate |
| Feb | 3.3 | Moderate |
| Mar | 4.5 | Bright |
| Apr | 5.6 | Bright |
| May | 6.1 | Intense |
| Jun | 6.1 | Intense |
| Jul | 5.9 | Bright |
| Aug | 5.4 | Bright |
| Sep | 4.6 | Bright |
| Oct | 3.9 | Moderate |
| Nov | 3.0 | Moderate |
| Dec | 2.4 | Moderate |
Where is Forest Park?
Forest Park sits at 33.6°N, 84.4°W, 988 ft above sea level, in United States. The nearest listed city is Riverdale, 4.3 mi away.
Topography around Forest Park
How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Forest Park.
Within 2 miles, the terrain around Forest Park has only modest variations in elevation — a maximum elevation change of 220 ft around an average of 951 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 643 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 1,742 ft.
The land around Forest Park is covered by trees (52%) and artificial surfaces (36%) within 2 miles, trees (67%) and artificial surfaces (22%) within 10 miles, and trees (81%) 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 Park (33.6221°, -84.3691°, elevation 988 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. 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).