Climate Insights for Heilbron

The climate in Heilbron is temperate. The average annual temperature is 17°C and approximately 659mm of precipitation falls per year. December is the wettest month, receiving around 133mm of rainfall. Heilbron is in the Southern Hemisphere. The seasons are reversed — summer runs from December to February, while winter falls between June and August. The summer months are: December, January, November. The coldest months are July, June, August, when temperatures can drop to 2°C.

Temperatures in Heilbron vary considerably across the year, with a 26°C difference between the coldest and warmest months. The warmest month is December, when average highs reach 28°C and the mean temperature sits around 21°C. July is the coolest month, with minimum temperatures around 2°C and an average of 10°C. On average, daily temperatures fluctuate by about 14°C between overnight lows and afternoon highs. The sharpest temperature change occurs between August and September, with a 4°C shift in average temperatures.

Heilbron is a relatively dry area, receiving approximately 659mm of precipitation annually, which averages out to around 55mm per month. The wettest month is December, averaging 133mm of rainfall. January and November also tend to see above-average precipitation. The driest month is August, with just 4mm. That's 129mm less than December, the wettest month. Rainfall is heavily concentrated in certain months, creating a distinct wet and dry season. Visitors should plan around these patterns, as the difference between peak and low months is dramatic.

Heilbron is mildly breezy, with an average annual wind speed of 18km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is October, averaging 21km/h, noticeable enough to affect lighter outdoor activities. The calmest conditions occur in May, with average winds dropping to 15km/h, making it an ideal period for wind-sensitive activities. There is moderate seasonal variation in wind speed, with a 6km/h gap between the calmest and windiest months.

It is currently autumn in Heilbron, which began on March 20, 2026. Heilbron is in the Southern Hemisphere, where the seasons are reversed — spring starts in September, summer in December, autumn in March, and winter in June. The warmest period peaks in December at around 28°C, while the coldest stretch bottoms out in July near 2°C. Winter is next, beginning on June 21, 2026 — 89 days from now.

The best time to visit Heilbron is during February, March, April, September, October and November, when the weather is most comfortable for travellers. During these months, average temperatures hover around 19°C with modest rainfall averaging 62mm per month. By contrast, December can be uncomfortably hot with highs reaching 28°C, while July is the coldest period with lows dropping to 2°C. A light rain jacket is recommended, though showers are generally brief and shouldn't disrupt your plans.

The table below shows monthly climate averages for Heilbron based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.