Free tools · Measured from space
Heat in Port St Johns
Summer 2025/26: the ground in Port St Johns reached about 34 °C on clear mornings. That is the ground (roofs, roads, soil), not the air. Only the summer of 2015/16 was hotter since 2014.
Land surface temperature is how hot the ground itself is: roofs, roads, bare soil and leaves, as a satellite sees them from above. Landsat passes at about 10 in the morning and sees only through clear skies. It is not the air temperature a weather station gives: on a sunny day the ground is often 10 to 20 degrees hotter than the air, and hard, dark, dry surfaces heat up most while trees, grass and water stay cooler.
What it is not: not the afternoon peak, not the night, not the air you feel in the shade, and not a reading at any one house. A month with clouds rests on few clear looks.
Summer 2025/26
- 33.7 °CThe ground, not the airDecember to February, clear mornings
- 2015/16Hottest summer since 201433.8 °C; the coolest was 2018/19, 30.4 °C
Every summer since 1987
Show the numbers
| When or what | Figure |
|---|---|
| Summer 1986 to 87 | 32.0 °C |
| Summer 1988 to 89 | 29.4 °C |
| Summer 1990 to 91 | 29.1 °C |
| Summer 1994 to 95 | 31.1 °C |
| Summer 1996 to 97 | 32.1 °C |
| Summer 1997 to 98 | 32.0 °C |
| Summer 1998 to 99 | 28.7 °C |
| Summer 1999 to 00 | 30.4 °C |
| Summer 2000 to 01 | 31.6 °C |
| Summer 2001 to 02 | 30.0 °C |
| Summer 2002 to 03 | 34.6 °C |
| Summer 2007 to 08 | 31.7 °C |
| Summer 2011 to 12 | 30.8 °C |
| Summer 2012 to 13 | 31.2 °C |
| Summer 2015 to 16 | 33.8 °C |
| Summer 2016 to 17 | 32.1 °C |
| Summer 2017 to 18 | 31.1 °C |
| Summer 2018 to 19 | 30.4 °C |
| Summer 2019 to 20 | 31.9 °C |
| Summer 2020 to 21 | 30.4 °C |
| Summer 2021 to 22 | 30.6 °C |
| Summer 2022 to 23 | 30.5 °C |
| Summer 2023 to 24 | 32.2 °C |
| Summer 2024 to 25 | 31.6 °C |
| Summer 2025 to 26 | 33.7 °C |
The shape of a year
Show the numbers
| When or what | Figure |
|---|---|
| January | 32.4 °C |
| February | 31.6 °C |
| March | 28.7 °C |
| April | 24.3 °C |
| May | 21.9 °C |
| June | 19.0 °C |
| July | 18.8 °C |
| August | 22.2 °C |
| September | 26.0 °C |
| October | 29.6 °C |
| November | 31.4 °C |
| December | 31.1 °C |
Warmest and coolest wards
Each ward’s summers against Port St Johns’s average, since 2014. Where the ground is mostly roofs, roads and bare earth it reads hotter; where there are trees, grass, gardens or water it reads cooler.
Coolest
- Ward 6 (Port St Johns, Mthumbane)−2.4 °C
- Ward 10−1.5 °C
- Ward 5 (Bholani, Caguba)−1.5 °C
- Ward 2 (Sihlanjeni)−1.3 °C
- Ward 1−1.3 °C
Every ward
- Ward 19+3.4 °C
- Ward 20+3.2 °C
- Ward 17+1.5 °C
- Ward 14+1.2 °C
- Ward 7+0.9 °C
- Ward 18+0.9 °C
- Ward 13+0.5 °C
- Ward 4 (Madikana, Mgxabakazi)+0.4 °C
- Ward 12 (Mafusini, Ngqotsini)+0.4 °C
- Ward 15+0.4 °C
- Ward 8+0.3 °C
- Ward 21+0.2 °C
- Ward 9 (Bizana, Luqaqweni)−0.5 °C
- Ward 3−0.6 °C
- Ward 16 (Kankqolo, Kohlo)−0.6 °C
- Ward 11 (Nomngcingi)−1.2 °C
- Ward 1−1.3 °C
- Ward 2 (Sihlanjeni)−1.3 °C
- Ward 5 (Bholani, Caguba)−1.5 °C
- Ward 10−1.5 °C
- Ward 6 (Port St Johns, Mthumbane)−2.4 °C
Places in each ward: © OpenStreetMap contributors.
Month by month
| Month | Land surface temperature | Clear looks |
|---|---|---|
| October 2026 | 28.1 °C | 3.2 |
| September 2026 | 22.0 °C | 2.2 |
| August 2026 | 22.2 °C | 4.4 |
| July 2026 | 19.0 °C | 3.4 |
| June 2026 | 20.6 °C | 3.3 |
| May 2026 | 24.2 °C | 4.7 |
| April 2026 | 26.4 °C | 3.9 |
| March 2026 | 30.3 °C | 2.1 |
| February 2026 | 33.4 °C | 3.0 |
| January 2026 | 36.7 °C | 2.4 |
| December 2025 | 30.9 °C | 1.4 |
| November 2025 | 30.6 °C | 0.9 |
| October 2025 | 31.4 °C | 3.3 |
| September 2025 | 25.2 °C | 2.0 |
| August 2025 | 21.7 °C | 4.6 |
| July 2025 | 18.7 °C | 3.6 |
| June 2025 | 18.3 °C | 4.0 |
| May 2025 | 21.2 °C | 6.2 |
| April 2025 | 24.7 °C | 2.5 |
| March 2025 | 28.1 °C | 5.2 |
| February 2025 | 30.4 °C | 2.2 |
| January 2025 | 31.6 °C | 1.1 |
| December 2024 | 32.8 °C | 2.0 |
| November 2024 | 27.7 °C | 0.5 |
“Clear looks” is how many times the average 240 m patch of the place was seen through clear sky that month. Under one, part of the place was not seen at all, so the figure leans on the part that was.
Every municipality, ranked · Everything we hold for Port St Johns
Source
Measured from space by the American Landsat satellites: the ground, not the air.
How we worked this out
Landsat 5 to 2011, Landsat 7 to bridge the gaps, Landsat 8 and 9 from 2013: different satellites pass at slightly different times, so compare summers within the same years first.
What we changed: we kept only the clear land cells (no cloud, cloud shadow, snow or water, with a margin round each cloud), read them at 480 m, and averaged them over each 2026 ward each month; larger places are the sums of their wards.
Landsat imagery courtesy of the U.S. Geological Survey (Landsat Collection 2 surface temperature, through Digital Earth Africa’s copy).
Dataset: land surface temperature by ward, release of 13 November 2026.