California International Marathon Runs Fast and Cold Into Sacramento

The California International Marathon sends runners 26.2 miles downhill from Folsom to Sacramento, shedding 333 feet of net elevation along the way. In its largest editions — 9,182 finishers in 2023 and 7,980 in 2022 — the field has posted median finish times clustering around 3:49–3:50, numbers that reflect just how much this course rewards runners who arrive fit and pace honestly. December in Northern California means cold, occasionally wet mornings, and 2026 looks to follow that tradition.

By the numbers

The full-field editions of CIM tell a consistent story. From 2019 through 2023, finisher counts grew from 7,470 to 9,182, with the 2024 edition noted for record participation. The overall median in the three most comparable years — 2021, 2022, and 2023 — sat within seconds of each other at roughly 3:49. Men's medians ranged from 3:38 to 3:40 across those editions; women's medians from 4:01 to 4:03. The women's field has grown steadily, from 3,121 finishers in 2021 to 3,646 in 2023.

How the course runs

CIM is a net-downhill point-to-point, and its profile is genuine: the course drops 116 feet between miles 15.1 and 21.8 at a gentle average grade of 0.3%, with steeper descents of 101 feet (miles 2.2–3.8, avg 1.2%) and 88 feet (miles 10.7–11.2, avg 3.5%) earlier on. The final miles into Sacramento are essentially flat. For runners, that means the course rewards patience — the early drops can encourage a pace that feels effortless but extracts a cost later.

No checkpoint split data was provided for this edition, so a pace-by-mile table is not available. What the overall splits do show is that the course's downhill character doesn't prevent the field from fading; the back half is harder than the profile alone suggests.

Pacing patterns

Positive splits are the norm at CIM, as they are at virtually every mass-participation marathon. In the full-field editions, 72% to 85% of finishers ran the second half slower than the first, with average second-half slowdowns ranging from 8.2% (2021) to 12% (2019). The 2021 edition — broken clouds, 47–57°F, light wind — produced the most even racing, with 1,012 negative splits. The wet, windier 2019 conditions (90% humidity, wind ~9 mph) coincided with the largest slowdown and the slowest median of the comparable years at 3:56:55. The lesson is straightforward: the downhill first half invites optimism; the flat finish demands that runners have something left.

The weather question

CIM's best conditions have come in the 47–57°F range with modest wind and partial cloud cover — 2021 being the clearest example of that sweet spot. Cooler, wetter days like 2019 (light rain, 90% humidity, wind ~9 mph) pushed the median nearly eight minutes slower than the 2021–2023 cluster. The 2026 forecast — 38–48°F, mist, wind ~8 mph, 93% humidity — sits at the colder, damper end of the race's historical range, closer to 2019 than to 2021. That doesn't preclude fast times, but runners should expect conditions that demand proper layering at the start and careful early pacing.

What it takes

In the full-field years, breaking into the top 10% has required roughly 2:51–2:55; the top 25% threshold has sat between 3:14 and 3:20. The overall median of 3:49–3:50 is a useful anchor for mid-pack runners. Winning times on the men's side have been remarkably consistent: 2:11:00 to 2:13:35 across 2019, 2021, and 2022, with 2:11:09 in 2023.

What to watch

The 2024 edition was noted for record participation; whether 2026 sustains or surpasses that level will be one of the field-size storylines heading into race day. The forecast's combination of mist and 93% humidity is the most humid in the dataset — how that affects the field's second-half slowdown relative to the 8–12% range seen historically is worth tracking. And with the course's BQ-friendly profile and a field that has demonstrated it can run 3:49 medians in comparable December conditions, the question of how many qualifiers the 2026 edition produces against that historical baseline is the clearest performance narrative to follow.