Great South Run
Great South Run race day weather
Cool start, steady wind
Runners will face a temperature range from 57°F to 59°F throughout the race, with a consistent humidity level of 76%. Winds will come from the SW at 18 mph, creating a headwind effect. Given the conditions, runners should consider pacing conservatively and staying hydrated to maintain performance.
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Great South Run route and elevation
The Great South Run course has about 27 ft (8 m) of climbing and 24 ft (7 m) of descent, and finishes near the elevation it starts. It has no steep miles: no mile climbs more than 10 ft (3 m).
What the hills cost
The hills change finish times by less than 0.2% here, under half a minute for a 1:35:00 runner.
Hills only, priced mile by mile on the course map. The pace calculator above adds the race-day weather.
Even-effort splits for a 1:20:00, 1:35:00 or 1:50:00 finish
| Mile | Climb | Descent | 1:20:00 | 1:35:00 | 1:50:00 |
|---|---|---|---|---|---|
| 1 | 9 ft | 4 ft | 8:02 | 9:33 | 11:03 |
| 2 | 7 ft | 5 ft | 8:01 | 9:30 | 11:01 |
| 3 | 3 ft | 5 ft | 7:59 | 9:29 | 10:59 |
| 4 | 2 ft | 3 ft | 8:00 | 9:30 | 10:59 |
| 5 | 4 ft | 8 ft | 7:58 | 9:29 | 10:59 |
| 6 | 2 ft | 3 ft | 8:00 | 9:29 | 10:59 |
| 7 | 4 ft | 0 ft | 8:01 | 9:32 | 11:02 |
| 8 | 10 ft | 11 ft | 8:00 | 9:29 | 10:59 |
| 9 | 5 ft | 3 ft | 8:00 | 9:31 | 11:01 |
| 10 | 1 ft | 3 ft | 7:59 | 9:28 | 10:58 |
Explore the Great South Run course with the weather and your pace along the route, or compare it with other races.
Get your personalized Great South Run race plan
A mile-by-mile breakdown of where your time goes, weather-adjusted splits, fueling timeline with aid stations, packing checklist, carb tracker, spectator guide, all built around your goal and race-day conditions.
About the Great South Run
The Great South Run is an annual 10-mile road race in Portsmouth, England, first held in 1990. The flat, largely coastal course starts near Southsea Castle and finishes along the Southsea seafront, passing Portsmouth Historic Dockyard and the Spinnaker Tower. It hosts the UK Athletics 10-Mile Championships and draws over 20,000 finishers most years.
