Herrin, United States experiences average highs of 20°C (68°F) and lows of 11°C (52°F) throughout the year. Rainfall is moderate, averaging about 10 rainy days per month. Sunshine is abundant, averaging about 9 hours per day. Average highs have stayed broadly stable across the available records.
Herrin, United States Weather & Climate 2026
Monthly climate averages for Herrin, United States. Based on 10-year ERA5 reanalysis data.
Climate Overview
Drier season: Jan–Dec 
Wetter season: Mar–Aug At-a-Glance Climate Summary
Live Weather & Air Quality
Key figures
Climate Score
5.8/10
Best: May, June, September, October
UV Index
5
Low
Temperature 20°C / 11°C
Feels Like 20°C / 10°C
Rainy Days 10
Rainfall 102 mm
Sunshine 9 h
Humidity 68%
Wind Speed 17 km/h
Dew Point 10°C
Snow Days 2 days
Frost Days 9 days
Hottest Month
32°C
July
Avg Low23°C
Rain11days
Coldest Month
-1°C
January
Avg High6°C
Rain9days
Driest Month
7days
September
Avg High28°C
Avg Low19°C
Windiest Month
20 km/h
March (Gusts 45)
Worst Time to Visit
Consider avoiding January, February, December due to less favorable weather conditions.
Sun Position
Sunrise 05:35
Daylight 14.8h
Sunset 20:21
Live conditions—
Herrin on the map · live conditions
Herrin, United States
- Continent
- Americas
- Country
- United States
- City
- Herrin
- Population
- 12.9K
- Elevation
- 128 m
- Coordinates
- 37.80°, -89.03°
Seasonal Breakdown
Spring
Mar–May
Avg High 20°C
Avg Low 11°C
Rain 12 days/mo
1/3 best months
Summer
Jun–Aug
Avg High 31°C
Avg Low 22°C
Rain 10 days/mo
1/3 best months
Autumn
Sep–Nov
Avg High 21°C
Avg Low 13°C
Rain 7 days/mo
2/3 best months
Winter
Dec–Feb
Avg High 8°C
Avg Low 0°C
Rain 9 days/mo
Climate Charts
Based on historical averages (2016–2025)
Monthly Temperatures
HighLowShaded bands show the typical range across the available yearly records.
Line chart showing monthly temperatures. Jan: 6°C / -1°C . Feb: 10°C / 1°C . Mar: 16°C / 6°C . Apr: 20°C / 10°C . May: 25°C / 16°C . Jun: 30°C / 21°C . Jul: 32°C / 23°C . Aug: 30°C / 22°C . Sep: 28°C / 19°C . Oct: 22°C / 13°C . Nov: 14°C / 6°C . Dec: 9°C / 2°C .
Monthly Rainfall
Rainfall
Bar chart showing monthly rainfall. Jan: 106 mm. Feb: 104 mm. Mar: 136 mm. Apr: 136 mm. May: 128 mm. Jun: 95 mm. Jul: 104 mm. Aug: 102 mm. Sep: 69 mm. Oct: 88 mm. Nov: 76 mm. Dec: 84 mm.
Monthly Humidity
Humidity
Line chart showing monthly humidity. Jan: 68%. Feb: 67%. Mar: 64%. Apr: 64%. May: 70%. Jun: 67%. Jul: 71%. Aug: 70%. Sep: 67%. Oct: 65%. Nov: 68%. Dec: 70%.
Monthly Wind Speed
Wind SpeedGusts
Bar chart showing monthly wind speed. Jan: 18 km/h . Feb: 19 km/h . Mar: 20 km/h . Apr: 20 km/h . May: 17 km/h . Jun: 15 km/h . Jul: 13 km/h . Aug: 13 km/h . Sep: 13 km/h . Oct: 17 km/h . Nov: 17 km/h . Dec: 18 km/h .
Sunshine
Sunshine
Sunshine: Jan: 6h. Feb: 7h. Mar: 8h. Apr: 9h. May: 10h. Jun: 12h. Jul: 12h. Aug: 11h. Sep: 10h. Oct: 8h. Nov: 7h. Dec: 6h.
UV Index
UV Index
Bar chart showing monthly UV index. Jan: UV 3. Feb: UV 4. Mar: UV 5. Apr: UV 6. May: UV 7. Jun: UV 7. Jul: UV 8. Aug: UV 7. Sep: UV 6. Oct: UV 5. Nov: UV 3. Dec: UV 2.
Monthly Daylight Hours
Daylight12h reference
Monthly Dew Point & Comfort
Dew Point Dry Comfortable Humid Muggy Oppressive
Snow Days
Snow DaysSnowfall
Snow Days: Jan: 4 days. Feb: 4 days. Mar: 1 days. Apr: 0 days. May: 0 days. Jun: 0 days. Jul: 0 days. Aug: 0 days. Sep: 0 days. Oct: 0 days. Nov: 1 days. Dec: 2 days.
Climate Trends
Average highs have stayed broadly stable across the available records. Average rainfall has remained broadly steady.
2016 to 2025
Avg high Avg rainfall
Climate summary
| Last 12 months | All years | |
|---|---|---|
| Hottest month | Jul 2025 · 32°C | Jul · 32°C |
| Coldest month | Jan 2025 · -4°C | Jan · -1°C |
| Wettest month | Apr 2025 · 207 mm | Mar · 136 mm |
| Windiest month | Mar 2025 · 23 km/h | Mar · 20 km/h |
Month-by-Month Weather Table
January
Poor 
February
Poor March
Fair April
Good May best
Excellent June best
Excellent July
Fair August
Good September best
Excellent October best
Excellent November
Fair December
Poor | Month | Temp | Feels Like | Rain | Sun | Humidity | UV | Status | Details |
|---|---|---|---|---|---|---|---|---|
| January | 6°C / -1°C | 2°C / -6°C | 9days (106 mm) Wet | 5.6h Fair | 68% Muggy | 2.7 Moderate | Poor | View Details |
| February | 10°C / 1°C | 7°C / -4°C | 9days (104 mm) Wet | 6.7h Fair | 67% Muggy | 3.7 Moderate | Poor | View Details |
| March | 16°C / 6°C | 13°C / 2°C | 11days (136 mm) Wet | 7.5h Good | 64% Muggy | 5.2 High | Fair | View Details |
| April | 20°C / 10°C | 19°C / 7°C | 12days (136 mm) Wet | 9.2h Good | 64% Muggy | 5.9 High | Good | View Details |
| May best | 25°C / 16°C | 26°C / 15°C | 13days (128 mm) Wet | 10h Excellent | 70% Muggy | 6.9 High | Excellent | View Details |
| June best | 30°C / 21°C | 33°C / 22°C | 10days (95 mm) Wet | 12h Excellent | 67% Muggy | 7.4 Very High | Excellent | View Details |
| July | 32°C / 23°C | 36°C / 26°C | 11days (104 mm) Wet | 12.1h Excellent | 71% Muggy | 7.5 Very High | Fair | View Details |
| August | 30°C / 22°C | 34°C / 24°C | 10days (102 mm) Wet | 10.9h Excellent | 70% Muggy | 7 High | Good | View Details |
| September best | 28°C / 19°C | 30°C / 20°C | 7days (69 mm) Good | 10.2h Excellent | 67% Muggy | 5.9 High | Excellent | View Details |
| October best | 22°C / 13°C | 21°C / 11°C | 7days (88 mm) Good | 8.3h Good | 65% Muggy | 4.5 Moderate | Excellent | View Details |
| November | 14°C / 6°C | 11°C / 2°C | 8days (76 mm) Wet | 6.9h Fair | 68% Muggy | 3.1 Moderate | Fair | View Details |
| December | 9°C / 2°C | 6°C / -2°C | 9days (84 mm) Wet | 5.6h Fair | 70% Muggy | 2.4 Moderate | Poor | View Details |
Compare Nearby City Climates
Frequently Asked Questions
The best months to visit Herrin are May, June, September, October, when temperatures are comfortable and rainfall is at its lowest. This is based on 10-year climate averages for Herrin, scoring temperature, rainfall, humidity, and sunshine hours.
The hottest month in Herrin is July, with average daytime highs of 32°C (89°F). Plan outdoor activities for early morning or late afternoon if visiting during this period.
The coldest month in Herrin is January, with average overnight lows of -1°C (29°F). Pack warm layers and expect shorter daylight hours during this period.
The wettest month in Herrin is March, averaging 136mm of precipitation across 11 rainy days. An umbrella or waterproof jacket is essential.
The rainy season in Herrin runs through May, April, March, July, with the heaviest rainfall in May. Based on 10-year averages for Herrin.
Herrin receives approximately 105 sunshine hours per year. The sunniest month is July with around 12 hours. Based on climate data for Herrin.
The least favorable months to visit Herrin are January, February, December, primarily due to less favorable weather conditions. For the best conditions, consider May, June, September, October instead.
The annual average UV index in Herrin is 5, classified as moderate. Standard sun protection (sunscreen, hat) is recommended during prolonged outdoor exposure.
Average humidity in Herrin is 68%, classified as moderate. Humidity levels are generally comfortable and should not affect outdoor activities for most people.
Yes, Herrin receives snow. Months with snowfall average 2 snow days and 4 cm (2 in) of accumulation, with about 9 frost days during winter.
Average wind speeds in Herrin are 17 km/h (11 mph). The windiest month is March with peak winds reaching 20 km/h (12 mph) (gusts up to 45 km/h / 28 mph).
Herrin averages 6 clear-sky days per month with overall cloud cover around 55%. The clearest skies occur in October.
The annual average dew point in Herrin is 10°C (50°F), which feels pleasant with low humidity. Outdoor activities are comfortable year-round from a humidity standpoint.
Herrin has a Humid Subtropical climate, classified as Cfa under the Köppen system. Temperate climates have mild winters and warm summers, with rainfall spread across the year and four distinct seasons.
The 'feels like' temperature in Herrin ranges from 10°C (50°F) to 20°C (68°F) on average. The 'feels like' temperature closely matches the actual temperature throughout most of the year.
Yes, June is a great time to visit Herrin. It earns a climate score of 7.7/10 with Excellent.
For June in Herrin, pack Umbrella, Waterproof jacket, Breathable clothing, Sunscreen (SPF 30+), Sun hat. With average highs of 30°C (86°F) and 10 rainy days, these essentials will keep you comfortable.
Data Source
Climate data derived from ERA5 reanalysis (ECMWF), averaged over 2016–2025. Sea surface temperature from marine reanalysis data. Climate scores and seasonal estimates are computed by WorldStats.
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