Swim
1.9 km
Kailua-kona Swim
- Setting
- Kohala Coast
Settle into the Kailua-Kona swim before the exposed bike.
Source: 2027 current organiser descriptionRace IntelligenceKohala Coast, United States
Race Hawai`i with respect for the lava and wind.
Enter four numbers you already train with. You get a likely finish range, target paces and watts, and a plan for Hawai`i.
Published route evidence. Final 2027 route pending. Checked 14 Sept 2026.
01 Race Card
Your first range uses conservative assumptions. Add optional evidence to make it more specific. It is calculated in your browser and saved only on this device.
02 The course
You swim off Kailua-Kona, ride through exposed lava fields, then run along Hawai`i's coastline. Respect the wind and keep bike effort controlled so the run stays useful.
Swim
1.9 km
Settle into the Kailua-Kona swim before the exposed bike.
Source: 2027 current organiser descriptionBike
90 km
Ride the lava-field course by effort and protect the run from wind-driven surges.
Source: 2027 current organiser descriptionRun
21.1 km
Use the patience saved on the bike for a controlled coastal run.
Source: 2027 current organiser descriptionThese facts come from the organiser’s latest published material: swim, 2027 current organiser description; bike, 2027 current organiser description; run, 2027 current organiser description. They describe the character of the course. They do not confirm the final 2027 route.
03 Race plan
One job for each part of this course. The distance markers tell you when the job changes. The course tells you why.
Swim
Establish a sustainable rhythm off Kailua-Kona.
Bike
Use planned effort through the exposed lava fields rather than chasing speed into the wind.
Run
Start controlled and progress only when earned.
04 Race week
There is no useful 2027 forecast this far out. For now, past race dates give us a point of reference. Closer to the race, the forecast will tell us whether the plan needs changing.
A race-day forecast is not meaningful yet; check back closer to the event.
Historical baseline, 2019–2025 · Open-Meteo historical archive · Updated 2026-09-14.Historical comparison only. This is not a forecast for 2027.
05 Method
Your CSS, FTP, weight and run threshold create the first range. Open-water, bike, run and execution evidence can replace broad assumptions. Course data and the historical conditions baseline shape every simulation.
Confidence is built from four inputs
It starts with the targets in your Race Card, then samples the parts of a 70.3 that vary: open-water pace, transitions, bike speed at the planned power, and the drop in run performance after the swim and bike. Repeating that calculation produces a likely range rather than a single heroic number.
The current time calculation uses this race’s published distances, or standard 70.3 distances where none are published, with the available course headings, elevation and exposure evidence. Weather scenarios vary temperature, dew point, wind, gusts, rain and water conditions together. Unknown route detail stays visible as uncertainty rather than false precision.
It is not predicting your exact finishing time, placing, or race-day weather. It answers a narrower question: given the plan and the information we have, what range of day is plausible, and where is the uncertainty coming from?
Confidence is not a permanent “low”. It is recalculated across four separate inputs:
It starts low when those inputs are broad. It can become moderate or high as the evidence improves. A narrower range means better information, not a guarantee.
Evidence
Course status: Partially verified. The organiser’s descriptions and latest published route profiles are in use. The final 2027 route is not yet confirmed. Last checked 2026-09-14.