Is Surat Thani sunnier than Ko Samui?

Ko Samui is the sunnier: about 2,342 hours of sunshine a year versus 2,175 — a difference of 167 hours.

Which is warmer, Surat Thani or Ko Samui?

Year-round daytime highs are similar: Surat Thani averages 30°C (86°F), Ko Samui 29°C (84°F).

Which is better in winter (November–February), Surat Thani or Ko Samui?

They are close in the November–February window: Surat Thani averages 71/100 (about 29°C days), Ko Samui 71/100 (about 28°C).

Surat Thani vs Ko Samui: which is sunnier?

🇹🇭 Thailand vs 🇹🇭 Thailand · 112 km apart · long-term climate normals (NASA POWER, 2001–2020)

Ko Samui is the sunnier overall: about 2,342 hours of sunshine a year to Surat Thani's 2,175. Ko Samui has the higher Sunshine Score in 1 of 12 months; the other 11 are within 2 points.

Scores are the 0–100 Sunshine Score — sunshine, daytime warmth and dryness in one number, per month.

At a glance

	Surat Thani	Ko Samui
Sunshine hours / year	2,175	2,342
Sunniest month	February (86/100)	February (86/100)
Nov–Feb average score	71/100	71/100
Jun–Aug average score	64/100	65/100
Rain / year	2,329 mm	2,088 mm
Peak midday UV	11 (extreme)	11 (extreme)

Surat Thani vs Ko Samui month by month

Month	Sunshine Score		Day high °C		Rain mm
Month	Surat Thani	Ko Samui	Surat Thani	Ko Samui	Surat Thani	Ko Samui
January	69	68	29°	28°	123	135
February	86	86	30°	28°	31	38
March	71	72	31°	29°	110	114
April	72	76	32°	30°	104	90
May	64	65	31°	30°	217	170
June	64	65	30°	30°	221	167
July	64	65	29°	29°	223	166
August	64	66	29°	29°	216	144
September	64	65	29°	29°	264	181
October	64	65	29°	28°	276	246
November	64	65	29°	28°	320	375
December	64	65	28°	28°	224	262

The sunnier month by month: Jan even · Feb even · Mar even · Apr Ko Samui · May even · Jun even · Jul even · Aug even · Sep even · Oct even · Nov even · Dec even.

When to pick which

November–February: too close to call — Surat Thani averages 71/100, Ko Samui 71/100. Daytime highs are similar (29°C vs 28°C). See the winter sun ranking.
March–May: too close to call — Surat Thani averages 69/100, Ko Samui 71/100. Daytime highs are similar (31°C vs 30°C).
June–August: too close to call — Surat Thani averages 64/100, Ko Samui 65/100. Daytime highs are similar (29°C vs 29°C).
September–October: too close to call — Surat Thani averages 64/100, Ko Samui 65/100. Daytime highs are similar (29°C vs 29°C).

Full month-by-month guides: Surat Thani weather by month · Ko Samui weather by month · Best time to visit Thailand.

More comparisons: Surat Thani vs Nakhon Si Thammarat · Surat Thani vs Phuket · Surat Thani vs Krabi · Ko Samui vs Nakhon Si Thammarat · Ko Samui vs Rayong · Ko Samui vs Krabi · all head-to-heads