January is one of the strongest months in Koh Tao (2nd)
Best window · 8.9/10January averages 28°C (82°F) and humidity near 78%, so the practical pattern is early mornings, a long midday break, and evenings back outside.
Rainfall runs 56 mm, so plan one flexible day in three; you still get about 21 days with 6+ hours of sunshine and 11.5 hours of daylight.
A 8.9/10 puts this among the year's best months in Koh Tao (2nd of 12); only March scores higher, at 9.2/10.
Plan for peak pricing, with this is one of the busiest months here. You are paying the year's highest rates for the year's best conditions — book early or shift a few weeks either side.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a packable rain layer.
February in Koh Tao — reliably good (4th best month)
Good · 7.6/10February averages 28°C (82°F) and humidity near 80%, so the practical pattern is early mornings, a long midday break, and evenings back outside.
Monthly rainfall reaches 113 mm — wet for this destination — but about 20 days with 6+ hours of sunshine still break through, so keep one indoor fallback in the plan.
It scores 7.6/10 here, 4th of 12 months, against 9.2/10 in the destination's best month.
Plan for mid-season pricing, with crowds are moderate.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a proper rain shell rather than an umbrella.
Flexible dates? March scores 1.6 points higher here — enough to change the trip.
March in Koh Tao tops the year's climate scores
Best window · 9.2/10Days in March average 28°C (83°F) and humidity near 79% — front-load outdoor plans before the heat builds and treat the middle of the day as indoor time.
Budget for roughly 53 mm of rain this month — a flexible day or two helps — with about 28 days with 6+ hours of sunshine and 11.9 hours of daylight to work around it.
On our climate-comfort scale this is the top-ranked month of the year for Koh Tao at 9.2/10 — the reference point every other month on this page is measured against.
Budget for peak pricing, and this is one of the busiest months here. You are paying the year's highest rates for the year's best conditions — book early or shift a few weeks either side.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a packable rain layer.
April in Koh Tao — reliably good (3rd best month)
Good · 8.4/10April averages 30°C (85°F) and humidity near 76%, so the practical pattern is early mornings, a long midday break, and evenings back outside.
Rainfall runs 91 mm, so plan one flexible day in three; you still get about 27 days with 6+ hours of sunshine and 12.2 hours of daylight.
It scores 8.4/10 here, 3rd of 12 months, against 9.2/10 in the destination's best month.
Figure on mid-season pricing, with crowds are moderate.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a packable rain layer.
May in Koh Tao: mixed conditions, plan around the weather
Trade-offs · 6.6/10Days in May average 30°C (86°F) and humidity near 78% — front-load outdoor plans before the heat builds and treat the middle of the day as indoor time.
This is the year's wettest stretch at 261 mm, but with about 21 days with 6+ hours of sunshine it is not a total loss; an indoor fallback covers the risk.
That is 6.6/10 on the same scale — 7th of 12 months, versus 9.2/10 for the best month here.
Expect low-season pricing, and crowds are light for this destination.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a proper rain shell rather than an umbrella.
If your dates are flexible, March is materially better in Koh Tao — 2.6 points higher on the same scale.
June in Koh Tao — middling scores, decent value
Trade-offs · 6.8/10June averages 29°C (85°F) and humidity near 79%, so the practical pattern is early mornings, a long midday break, and evenings back outside.
214 mm makes this the wettest stretch of the year, though about 21 days with 6+ hours of sunshine still appear — keep an indoor fallback ready.
It scores 6.8/10 here, 5th of 12 months, against 9.2/10 in the destination's best month.
Figure on low-season pricing, with crowds are light for this destination. That combination — decent conditions at the lowest rates of the year — is the best value window on this page.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a proper rain shell rather than an umbrella.
Flexible dates? March scores 2.4 points higher here — enough to change the trip.
July in Koh Tao: mixed conditions, plan around the weather
Trade-offs · 5.9/10July averages 29°C (84°F) and humidity near 80%, so the practical pattern is early mornings, a long midday break, and evenings back outside.
350 mm of rain puts this in monsoon territory — about 16 days with 6+ hours of sunshine across the whole month, and multi-day washouts are normal.
It scores 5.9/10 here, 9th of 12 months, against 9.2/10 in the destination's best month.
Plan for mid-season pricing, with crowds are moderate.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a proper rain shell rather than an umbrella.
Flexible dates? March scores 3.3 points higher here — enough to change the trip.
August in Koh Tao — middling scores, decent value
Trade-offs · 6.8/10Days in August average 29°C (84°F) and humidity near 81% — front-load outdoor plans before the heat builds and treat the middle of the day as indoor time.
This is the year's wettest stretch at 217 mm, but with about 23 days with 6+ hours of sunshine it is not a total loss; an indoor fallback covers the risk.
That is 6.8/10 on the same scale — 6th of 12 months, versus 9.2/10 for the best month here.
Expect mid-season pricing, and crowds are moderate.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a proper rain shell rather than an umbrella.
If your dates are flexible, March is materially better in Koh Tao — 2.4 points higher on the same scale.
September in Koh Tao — middling scores, decent value
Trade-offs · 6/10Days in September average 29°C (83°F) and humidity near 80% — front-load outdoor plans before the heat builds and treat the middle of the day as indoor time.
Expect monsoon-level rainfall at 265 mm: only about 17 days with 6+ hours of sunshine across the month, and stretches of heavy rain are normal.
That is 6/10 on the same scale — 8th of 12 months, versus 9.2/10 for the best month here.
Budget for low-season pricing, and crowds are light for this destination.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a proper rain shell rather than an umbrella.
If your dates are flexible, March is materially better in Koh Tao — 3.2 points higher on the same scale.
October in Koh Tao: mixed conditions, plan around the weather
Trade-offs · 5.8/10October averages 28°C (83°F) and humidity near 81%, so the practical pattern is early mornings, a long midday break, and evenings back outside.
283 mm of rain puts this in monsoon territory — about 16 days with 6+ hours of sunshine across the whole month, and multi-day washouts are normal.
It scores 5.8/10 here, 10th of 12 months, against 9.2/10 in the destination's best month.
Figure on low-season pricing, with crowds are light for this destination.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a proper rain shell rather than an umbrella.
Flexible dates? March scores 3.4 points higher here — enough to change the trip.
November in Koh Tao: mixed conditions, plan around the weather
Trade-offs · 5.1/10November averages 28°C (83°F) and humidity near 81%, so the practical pattern is early mornings, a long midday break, and evenings back outside.
356 mm of rain puts this in monsoon territory — about 10 days with 6+ hours of sunshine across the whole month, and multi-day washouts are normal.
It scores 5.1/10 here, 12th of 12 months, against 9.2/10 in the destination's best month.
Plan for low-season pricing, with crowds are light for this destination.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a proper rain shell rather than an umbrella.
Flexible dates? March scores 4.1 points higher here — enough to change the trip.
December in Koh Tao — workable with trade-offs
Trade-offs · 5.8/10Days in December average 28°C (82°F) and humidity near 78% — front-load outdoor plans before the heat builds and treat the middle of the day as indoor time.
Expect monsoon-level rainfall at 240 mm: only about 15 days with 6+ hours of sunshine across the month, and stretches of heavy rain are normal.
That is 5.8/10 on the same scale — 11th of 12 months, versus 9.2/10 for the best month here.
Budget for mid-season pricing, and crowds are light for this destination.
Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a proper rain shell rather than an umbrella.
If your dates are flexible, March is materially better in Koh Tao — 3.4 points higher on the same scale.
