Computed planning guide · Maui

Best Time to Snorkel in Maui: Month-by-Month Historical Conditions

This page compares the same 12-month historical model cohort across every month. It does not use generic travel prose or a seasonal rule of thumb: each row comes from stored HistoricalScoreMonth data.

Highest historical score June 2026 · 29.2/100
Calmest modelled mornings October 2025 · 76.8% calm from 6:00–11:00 local time

Coverage: 12/12 historical months · 12/12 with morning-calm data · 1 Oct 2025–30 Sep 2026.

Maui snorkeling conditions by month

The morning column is the modelled share of valid local 6:00–11:00 hours meeting the calm-water rule. “Morning advantage” is morning calm minus the all-hours calm share, in percentage points. It is a descriptive comparison, not a safety rating.

Historical Snorkel Score, morning calm-water share, all-hours calm-water share and sea-surface temperature by month for Maui.
Month Historical score Morning calm All-hours calm Morning advantage Mean SST Coverage
October 2025 27.2/100 76.8% 73.8% 3.0 pp 27.4°C81.3°F 31 valid days744 sampled hours
November 2025 24.4/100 54.0% 51.7% 2.3 pp 26.4°C79.5°F 30 valid days720 sampled hours
December 2025 24.1/100 57.4% 51.3% 6.1 pp 26.0°C78.8°F 31 valid days744 sampled hours
January 2026 25.0/100 69.7% 68.3% 1.4 pp 25.4°C77.8°F 31 valid days744 sampled hours
February 2026 24.1/100 31.4% 30.2% 1.2 pp 24.8°C76.7°F 28 valid days672 sampled hours
March 2026 23.3/100 30.3% 28.2% 2.1 pp 24.6°C76.3°F 31 valid days744 sampled hours
April 2026 27.3/100 57.3% 57.4% 0.0 pp 25.3°C77.5°F 30 valid days720 sampled hours
May 2026 27.3/100 12.3% 10.6% 1.6 pp 26.3°C79.4°F 31 valid days744 sampled hours
June 2026 29.2/100 3.3% 1.9% 1.4 pp 26.8°C80.2°F 30 valid days720 sampled hours
July 2026 27.9/100 6.5% 5.4% 1.1 pp 27.3°C81.2°F 31 valid days744 sampled hours
August 2026 24.7/100 21.3% 21.8% -0.5 pp 27.5°C81.6°F 31 valid days744 sampled hours
September 2026 23.6/100 19.3% 18.3% 1.0 pp 27.9°C82.2°F 30 valid days720 sampled hours

Methodology and limitations

  • Source cohort: versioned HistoricalScoreMonth rows only. Captured live forecasts are not substituted for missing historical months.
  • Historical Score: the stored monthly mean Snorkel Score, shown on a 0–100 scale. The month highlighted above is simply the highest stored monthly score in this window; no extra blended ranking formula is invented for this page.
  • Morning calm: percent of valid local 6:00–11:00 hours with significant waves at or below 0.60 m and wind at or below 5.4 m/s. Missing morning data stays missing.
  • All-hours calm: the same wave-and-wind rule across all valid hours in the month. A positive morning advantage means the stored mornings were calmer than the month overall.
  • Water temperature: modelled monthly mean sea-surface temperature for the same historical cohort. See the linked climate page for the separate multi-year temperature baseline.
  • Coverage: a stored historical month must meet the ranking system’s minimum valid-day threshold. Missing months render as incomplete rather than borrowing another year or repeating recent conditions.
  • Limits: these are model estimates at a forecast grid point. They do not measure coral health, wildlife, water clarity, beach access, local closures or in-water safety. Conditions still vary by coast and by day.

Scoring profile: historical-v2-2b079fef19289864 · profile hash 2b079fef19289864.

Sources: Open-Meteo Marine API and ERA5 via the Historical Weather API.