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havik.run/races/comrades-marathon/2026

Comrades Marathon

June 14, 2026 · 🇿🇦Durban, ZA

9d awayFavorable

Avg Temp

12\u00B0C

8\u00B0 \u2013 16\u00B0

Wind

3.2 m/s

NW headwind

Rain

15%

42% humidity

Pace Impact

+1.8%

10yr data

Course Profile · Weather Overlay

ultraGPX
ElevationTemperatureHeadwind

0-5km

4:52

-2s

5-10km

4:56

+4s

10-15km

4:48

-6s

15-20km

4:55

+3s

20-25km

4:58

+6s

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Features

Six reasons you'll never race blind again.

The difference between a PR and a blow-up is information. Here's yours.

Wind at Your Back (or Not)

Headwind, tailwind, and crosswind at runner height for every segment. You'll know exactly when to tuck in and when to push.

The Weather You'll Actually Run Through

Conditions at your arrival time, not just the start-line forecast. Mile 20 weather hits different.

Know When to Back Off

WBGT heat stress tells you what your body actually feels. Dial back before the bonk, not after.

No Hill Goes Unaccounted

Every climb and descent baked into your splits. Hold effort on the ups, bank time on the downs.

The Same Models Elite Coaches Use

Ely, Davies, Chapman -- peer-reviewed pace science used by Olympic programs. Now it's yours. For free.

Your Strategy, Your Splits

Even effort, negative split, or go-out-fast. Pick how you race and get splits built for the way you run.

How it works

Three steps to your race day edge.

01

Find your race

1,200+ courses loaded with 10 years of weather data. Or drop your own GPX. Either way, we know the course.

02

Dial in your strategy

Set your goal pace, pick your race plan: even effort, negative split, or go out hot. We build the splits.

03

Toe the line ready

Segment-by-segment splits adjusted for wind, heat, and elevation. You know the course. The course doesn't know you.

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Race Weather Strategy for Runners

Havik is a free race weather strategy platform that provides segment-by-segment wind, heat, and elevation analysis for runners. Upload your GPX file or browse our database of over 1,200 races to get science-backed pace adjustments for race day.

Features

  • Wind decomposition — headwind, tailwind, and crosswind at runner height for every segment
  • Time-aware forecasts — weather at your arrival time per segment, not just race start
  • WBGT heat index — wet-bulb globe temperature for real heat stress assessment
  • Gradient-adjusted pacing — uphills and downhills factored into your target pace
  • Peer-reviewed models — Ely, Davies, Chapman science used by elite coaches
  • Strategy modes — even effort, negative split, or even pace

How It Works

  1. Choose a race from our database or upload your GPX route file
  2. Set your target pace and race date
  3. Get segment-by-segment weather analysis and pace adjustments
  4. Race smarter with a science-backed strategy

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