IRONMAN 70.3 · Oceanside, California (swim and transition in Oceanside Harbor, bike through Camp Pendleton, finish on the Strand), United States

IRONMAN 70.3 Oceanside

Q: What is the water temperature at Oceanside 70.3?

IRONMAN lists an average of 61°F (16°C). Race mornings were 59°F in 2024, 57°F in 2025 and 64°F in 2026.

Q: Is Oceanside 70.3 wetsuit legal?

Usually yes. IRONMAN allows age-group wetsuits up to 76.1°F (24.5°C), and the harbor has been well below that on race day.

Q: How hilly is the Oceanside 70.3 bike?

About 2,649 ft (807 m) of climbing on IRONMAN's official route, with a steep pitch near mile 30 and the longest climb topping out near mile 37.

What IRONMAN 70.3 Oceanside demands, pillar by pillar, and when to start training each one.

Distance: 113.1 km
Elevation gain: 913 m
Descent: 913 m
High point: 220 m
Typical date: Late March or early April, Saturday
Next edition: Apr 3, 2027
Typical high: 21°C
Humidity: Cool, damp coastal mornings. Race-window humidity started at 85 to 98% and fell to about 55 to 65% by early afternoon (2024 to 2026, Open-Meteo). IRONMAN lists a typical high of 21°C and low of 7°C.
Terrain: Sheltered one-loop harbor swim, a hilly 90 km bike through Camp Pendleton with about 807 m of climbing, and a two-loop 21.1 km run along the Strand that is mostly flat with short ramps between beach and street level.

Check your readiness for IRONMAN 70.3 Oceanside

What this race demands

HeatLowrace-day highs were 17 to 23°C (2024 to 2026), under our 27°C line.
GutMediumdriven by the bike, where most fueling happens, then the run.
TerrainMediumdriven by the bike, with about 807 m of climbing, a steep pitch near km 48 and a long climb to km 60.
DurabilityMediumdriven by running off the bike: a half marathon after a hilly 90 km.
PacingHighdriven by the bike.
TaperMedium70.3 taper, final 2 weeks (from Mar 20, 2027).
HydrationMediumdriven by the bike, where you carry bottles.

When to train each part

Weeks counting back from race day. Tap or hover a row for its window.

Key course sections

Course profile

km · m

1
Bike km 0 to 40: rolling roads along the coast and through the base, staying under about 60 m
2
Bike km 47.5 to 48.5: the steepest pitch, about 59 m in under half a kilometer (roughly 13%, approximate from the course file)
3
Bike km 50.6 to 72: the longest climb, about 157 m up to the high point near km 60 (mile 37), then rolling descents back toward the coast
4
Run: two loops on the Strand and coastal streets, flat but with short ramps from beach to street level, finishing near the pier

Race-day weather history

Forecast: No forecast yet: the race is April 3, 2027, and reliable forecasts start about 14 days out.

Questions runners ask

When is IRONMAN 70.3 Oceanside 2027?

Saturday, April 3, 2027, per IRONMAN. General registration is sold out; IRONMAN lists special entries.

What is the water temperature at Oceanside 70.3?

IRONMAN lists an average of 16°C (16°C). Race mornings were 15°C in 2024, 14°C in 2025 and 18°C in 2026.

Is Oceanside 70.3 wetsuit legal?

Usually yes. IRONMAN allows age-group wetsuits up to 24°C (24.5°C), and the harbor has been well below that on race day.

How hilly is the Oceanside 70.3 bike?

About 807 m (807 m) of climbing on IRONMAN's official route, with a steep pitch near mile 30 and the longest climb topping out near mile 37.

Is the Oceanside 70.3 run flat?

Mostly. It's two loops along the Strand with short ramps between beach and street level, about 106 m (106 m) of climbing in total.

Sources

Know if you're ready for IRONMAN 70.3 Oceanside