← Weather & seasons in Thailand
On the thirty-year normal, Pattaya’s driest month is December (11.7 mm), which is also its coolest (23.3°C mean daily minimum). Wettest is October (224.5 mm) and hottest is April (33.0°C mean daily maximum). October’s rain is also when Pattaya’s own drainage limits show up most visibly — street flooding after heavy overnight rain is a recurring, reported event, not a rare exception.
The season bands, honestly
Pattaya does not have a dramatic wet-dry contrast the way some Thai stations do — it is a moderate coastal climate all year — but the measured normals still draw a clear best window and a clear worst one.
| Window | Measured conditions | What that means here |
|---|---|---|
| Nov – Feb | Cool season. Driest and coolest months of the year. | The best window: low humidity, low rainfall, comfortable evenings. December is both driest (11.7 mm) and coolest (23.3°C mean daily minimum). |
| Mar – Apr | Hot season builds. April hottest (33.0°C). | Rain still low, heat rising. Songkran (mid-April) falls here. |
| May – Jun | Transition. Rain starts building. | Shoulder season; fewer crowds, weather still mostly workable. |
| Jul – Sep | Southwest monsoon established. | Regular rain, rising humidity. Showers are typically shorter and heavier than an all-day soak, but this page has no official source that quantifies rain-hours-per-day for Pattaya specifically. |
| Oct | Wettest month (224.5 mm). | Peak flood-risk window. Recurring news reports of street flooding and drainage strain fall in this month most years. |
All figures are 1991–2020 normals for WMO station 48461 (Phatthaya). The “what that means here” column is our own reading against the published flood reports below, not a separate data source.
The flood risk, with receipts
Pattaya City’s own published annual summary lists drainage and flooding among the issues the municipality tracks, and the news record backs that up: overnight storms on 11 September 2026 left several roads underwater and disrupted traffic across the city, one instance of a pattern that recurs most wet seasons rather than a single unusual event. October is the month the thirty-year rainfall normal itself flags as the wettest (224.5 mm), so the two data points point the same way.
This is not a reason to avoid Pattaya in the wet season — most residents and long-stay visitors plan around it — but anyone renting for September or October, or booking ground-floor accommodation, should treat the possibility of standing water after heavy rain as a real planning factor rather than a remote one.
Jellyfish: what is and isn't confirmed
Moon jellyfish have been reported washing up along Pattaya’s beaches during the late rainy season, according to a Pattaya disaster-prevention officer, with lifeguards instructed to warn swimmers away from contact. Officials describe the sting as not life-threatening — itching and skin irritation, treated with a vinegar rinse — which is a materially different and less serious hazard than the box jellyfish sightings reported around Koh Samui and Koh Phangan, where officials have urged swimming only inside netted zones.
We could not find an official source giving a fixed seasonal calendar for jellyfish sightings at Pattaya specifically. Treat any lifeguard warning or posted sign at the beach as the operative information on any given day, rather than relying on a month-by-month rule.
What we could not confirm
- A full monthly rainfall or temperature table beyond the four extreme months (wettest, driest, hottest, coolest). The archive that would supply every other month could not be reached from this run.
- An official seasonal calendar for jellyfish sightings at Pattaya. News reports describe individual episodes, not a dated recurring pattern from a marine authority.
- Rain-hours-per-day within the wet season. The monthly totals are measured; how that rain is distributed across each day is not in this dataset.
- An official, quantified flood-frequency statistic for Pattaya (e.g. days of flooding per year). The evidence here is Pattaya City’s own acknowledgement that drainage and flooding are tracked issues, plus a recurring news record, not a published frequency count.
Frequently asked questions
December, on the numbers. It is both the driest month in the thirty-year normal — 11.7 mm, against an October peak of 224.5 mm — and the coolest, at a 23.3°C daily-minimum mean. The northeast monsoon has settled in by then, so humidity and rainfall are both at their lowest for the year at the same time the air finally cools off in the evenings. January and February are close behind on both counts.
It is real and it is recurring, not a one-off. October is Pattaya's wettest month on the thirty-year normal at 224.5 mm, and news reports of street flooding in the city turn up in most wet seasons — most recently overnight storms on 11 September 2026 that left several roads underwater and disrupted traffic. Pattaya City's own published summary lists drainage and flooding among the issues the municipality tracks. None of this means Pattaya is unlivable in the wet season — most residents plan around it — but a visitor renting a car or booking ground-floor accommodation for September or October should expect the possibility of standing water on some roads after heavy rain.
Occasionally, and it is worth being specific about which kind. Reports of moon jellyfish washing up along Pattaya's beaches have appeared during the late rainy season, according to a Pattaya disaster-prevention officer, with lifeguards told to warn swimmers to avoid contact. Moon jellyfish stings are not life-threatening — vinegar and rinsing the area is the advice officials gave — which is a different and far less serious hazard than the box jellyfish sightings reported around Koh Samui and Koh Phangan on the Gulf's outer islands. We could not confirm an official, dated seasonal pattern for jellyfish at Pattaya specifically, so treat this as an occasional risk to check locally rather than a fixed calendar window.
Both share the same wet-season timing — Pattaya's wettest month is October (224.5 mm) and so is Hua Hin's (250.4 mm) — but Hua Hin is drier overall across the year: 935.9 mm annually against Pattaya's 1,105.8 mm. See our Hua Hin vs Pattaya comparison for the fuller side-by-side, including cost of living and who each suits.
It gets hot: April is the hottest month on the normal at a 33.0°C daily-maximum mean. That is a full degree below Bangkok's April mean of 35.7°C on the same dataset, which is consistent with Pattaya's coastal position moderating the peak somewhat, but April in Pattaya is still the hot season by any measure, not a mild month.
Related guides
- Best time to visit Hua Hin — the same coast, drier overall.
- Hua Hin vs Pattaya — the fuller side-by-side comparison.
- Compare Thai cities — the same normals for twelve stations, side by side.
- Flooding & monsoon season in Thailand — the country-wide picture.
- Weather & seasons in Thailand — where this page zooms in from.
- Explore Thailand — the section this guide sits in.
Timed your visit. Now time the move.
If Pattaya is more than a trip, see what is actually listed here before the next wet season sets your calendar.
Sources & References
- WMO Climatological Standard Normals 1991–2020 — Thailand station data sheets (NCEI Accession 0253808), Phatthaya (Pattaya) station 48461: annual rainfall of 1,105.8 mm over 82.2 rain days, wettest month October (224.5 mm), driest month December (11.7 mm), hottest month April at a 33.0°C daily-maximum mean, coolest month December at a 23.3°C daily-minimum mean
- Pattaya City — published annual summary (B.E. 2564): area, boundaries, registered and unregistered population, drainage and flooding
- The Pattaya News — "Heavy Overnight Storms Cause Flooding and Traffic Chaos Across Pattaya", 11 September 2026: overnight rain left several roads underwater and disrupted traffic, one of a recurring pattern of flash-flooding reports each wet season
- The Thaiger — "Jellyfish invade Pattaya beaches, tourists warned to avoid contact": moon jellyfish reported along Pattaya's beaches for several days during the late rainy season, per Wallop Boonchu, a Pattaya disaster-prevention officer; described as not life-threatening but capable of causing itching and skin irritation, with lifeguards instructed to warn swimmers
Primary and official sources are cited above. Government rules, fees and procedures in Thailand change over time and vary by office; always confirm current requirements with the relevant authority before relying on them. BAANLYY never takes paid placement in editorial content.
