Climate Insights for Port St Johns

The climate in Port St Johns is temperate. The average annual temperature is 18°C and approximately 1052mm of precipitation falls per year. December is the wettest month, receiving around 136mm of rainfall. Port St Johns 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: January, February, March. The coldest months are July, June, August, when temperatures can drop to 8°C.

Port St Johns sees moderate temperature variation throughout the year, ranging from 8°C to 26°C. The warmest month is January, when average highs reach 26°C and the mean temperature sits around 21°C. July is the coolest month, with minimum temperatures around 8°C and an average of 14°C. On average, daily temperatures fluctuate by about 11°C between overnight lows and afternoon highs. The sharpest temperature change occurs between March and April, with a 3°C shift in average temperatures.

Port St Johns is a moderately rainy area, receiving approximately 1052mm of precipitation annually, which averages out to around 88mm per month. The wettest month is December, averaging 136mm of rainfall. January and November also tend to see above-average precipitation. The driest month is June, with just 24mm. That's 112mm 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.

Port St Johns is mildly breezy, with an average annual wind speed of 16km/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 17km/h, though still comfortable for most outdoor activities. The calmest conditions occur in May, with average winds dropping to 14km/h, making it an ideal period for wind-sensitive activities. Wind conditions are fairly consistent throughout the year, varying by only 3km/h between the calmest and windiest months.

It is currently winter in Port St Johns, which began on June 21, 2026. Port St Johns 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 January at around 26°C, while the coldest stretch bottoms out in July near 8°C. Autumn is next, beginning on March 20, 2026 — 3 days from now.

The best time to visit Port St Johns is during May, August and September, when the weather is most comfortable for travellers. During these months, average temperatures hover around 16°C with modest rainfall averaging 48mm per month. By contrast, January can be uncomfortably hot with highs reaching 26°C, while July is the coldest period with lows dropping to 8°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 Port St Johns 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.