Climate and average weather in Nan

In Nan, the summers are muggy, sweltering, showery, and mostly clear and the winters are hot and mostly clear.

Best: late November to early February

Over the course of the year, the temperature in Nan typically varies from 16°C to 36°C, and is rarely below 13°C or above 39°C. April is the hottest month of the year, while December is the coldest.

Based on the travel score, the best time of year to visit Nan for warm-weather activities is from late November to early February.

Hottest
Apr
36°
Coldest
Dec
17°
Wettest
Aug
312 mm
Driest
Feb
8 mm
Rain / yr
1402 mm
162 wet days
Daylight
10.9–13.1 h
shortest–longest
Elevation
205 m
18.8°N
Clearest
Feb
26% cloud

Nan is town in Nan province, Thailand.

Air quality
High
PM2.5 29.5 µg/m³ · 2019

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Nan weather by month, at a glance

The whole year in one picture — sky, rain, humidity, temperature and travel score. Click any band to jump to its full chart.

Each stripe is one measure across the whole year, stacked so a single day reads top to bottom. The sky band runs overcast grey on top down to clear blue at the base — more blue means sunnier — followed by the rainfall curve, the humidity band, a temperature strip that tints each stretch of the year by how warm its average high is, and the travel-score line at the foot. Scan straight down any date to read that day across every measure at once; the score climbs highest around late November to early February.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

Daily average highs and lows in Nan, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.

Temperatures in Nan stay fairly even through the year, without a distinct hot or cool season. The warmest month is April, with an average high of 36°C and low of 24°C; the coolest is December, with an average low of 17°C and high of 29°C.

Days typically run about 10°C warmer than nights, with the widest day–night swing (around 16°C) in February.

10°15°20°25°30°35°40°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan3016
Feb3317
Mar3520
Apr3624
May3425
Jun3225
Jul3125
Aug3124
Sep3124
Oct3123
Nov3120
Dec2917

How hot and cold Nan really feels

Feels-like highFeels-like lowactual air temp

The felt-temperature range through the year — heat index on the day's high (summer humidity), wind chill on the night's low (winter wind). The dashed lines are the plain thermometer; the gap is how much hotter or colder it really feels.

On the hottest afternoons, once humidity is folded in, Nan feels like about 40°C (around April 21). About 287 days a year carry some heat stress, and 46 of them tip into dangerous heat (feels-like above 39°C), peaking in April.

15°20°25°30°35°40°45°JanFebMarAprMayJunJulAugSepOctNovDecdangerous heat
Feels-like high (°C)Air high (°C)Feels-like low (°C)Air low (°C)
Jan30301616
Feb33331717
Mar37352020
Apr40362324
May39342525
Jun38322525
Jul37312525
Aug37312424
Sep37312424
Oct35312323
Nov33312020
Dec30291717

Average hourly temperature in Nan

A compact picture of the whole year, hour by hour: each column is a day, each row an hour, and the color is the modeled average temperature. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.

Read left to right for the day of the year and top to bottom for the hour of the day; the color is the modeled temperature, cool blues through to hot reds on the same scale as the other charts. A vertical slice is a single day's swing — coolest just before dawn, warmest in the mid-afternoon — while a horizontal slice follows one hour across the seasons. The darker overlay marks night and the lighter one the twilight around sunrise and sunset. Colors run warmest on April afternoons, near 36°C, and coldest before dawn in December, near 17°C.

JanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AM

Nan weather by month

Every month at a glance. Click a month for its detailed page.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan30° / 16°152116.4
Feb33° / 17°81.211.44.7
Mar35° / 20°304.611.92.9
Apr36° / 24°7811.612.42.2
May34° / 25°16621.512.92.3
Jun32° / 25°19023.413.12.5
Jul31° / 25°27326.5132.6
Aug31° / 24°31228.112.62.6
Sep31° / 24°22124.412.12.8
Oct31° / 23°7413.811.64.1
Nov31° / 20°223.511.15.4
Dec29° / 17°141.710.96.6

Chance of rain

How likely it is to rain on a typical day, and how that shifts across the wetter and drier seasons.

Nan gets about 1402 mm of precipitation a year. On a typical day the chance of rain is often wet, but that rises and falls sharply with the seasons.

The wetter season lasts 5.8 months, from around Apr 21 to Oct 15, peaking in August at about 91% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Feb 9.

August is the wettest month by volume, with 312 mm over about 28 wet days; February is the driest, with 8 mm.

0%10%20%30%40%50%60%70%80%90%100%JanFebMarAprMayJunJulAugSepOctNovDecdrierwetterdriermostly drysome rainoften wetvery wetAug 6 · 91%Feb 9 · 4%
Rain on a day (%)Rain days
Jan62
Feb51
Mar155
Apr3912
May6922
Jun7923
Jul8527
Aug9028
Sep8124
Oct4514
Nov124
Dec62

Monthly rainfall

Over a full year, Nan collects about 1402 mm of rain across 162 wet days — roughly 117 mm in an average month.

It doesn’t fall evenly. August is the wettest month with 312 mm, while February is the driest at just 8 mm. The three wettest months alone bring about 57% of the year’s total.

050100150200250300350JanFebMarAprMayJunJulAugSepOctNovDec1583078166190273312221742214
Rainfall (mm)Rain days
Jan152
Feb81
Mar305
Apr7812
May16622
Jun19023
Jul27327
Aug31228
Sep22124
Oct7414
Nov224
Dec142

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

How often the daytime sky is clear, partly cloudy or overcast.

In Nan, the average share of the sky covered by clouds shows significant seasonal variation over the course of the year.

The clearer part of the year begins around October 12 and lasts for 6.8 months, ending around May 6. The clearest month is February, when the sky is clear, mostly clear, or partly cloudy 90% of the time on average.

The cloudier part of the year begins around May 7 and lasts for 5.2 months, ending around October 11. The cloudiest month is August, when it is overcast or mostly cloudy 95% of the time.

0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%JanFebMarAprMayJunJulAugSepOctNovDecFeb 26 · 91%Aug 1 · 3%clearmostly clearpartly cloudymostly cloudyovercastclearercloudierclearer
Clearer (%)Cloudier (%)
Jan8416
Feb9010
Mar8515
Apr7228
May3268
Jun595
Jul595
Aug595
Sep1783
Oct5446
Nov7624
Dec7921

Daylight, sunrise and sunset

DaylightNight

Hours of daylight through the year, with sunrise and sunset times.

The gold band is daylight — sunrise runs along its lower edge, sunset along the upper — so it widens toward summer and pinches toward winter, with night the dark area above and below. The longest day, around June 2, brings about 13 h 06 min of light; the shortest, around January 1, only 10 h 54 min — a swing of roughly 2 h 12 min.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJanFebMarAprMayJunJulAugSepOctNovDec
Daylight (h)Sunrise (AM)Sunset (PM)
Jan11.06:575:56
Feb11.46:506:12
Mar11.96:316:23
Apr12.46:046:30
May12.95:476:40
Jun13.15:436:51
Jul13.05:526:53
Aug12.66:026:40
Sep12.16:086:14
Oct11.66:155:49
Nov11.16:295:35
Dec10.96:475:39

Sunny days

How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.

Nan averages about 12 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 0 and 24 days.

The sunnier stretch runs 6.4 months, from around Oct 18 to Apr 30. The sunniest month is March, with roughly 22 sunny days (bright).

The greyest month is August, down near 0 sunny days — about 98% fewer than the March peak.

051015202530JanFebMarAprMayJunJulAugSepOctNovDecsunniergreyersunniergloomymixedbrightbrilliantMar 124 daysAug 110 days
Sunny daysSky
Jan21Bright
Feb22Brilliant
Mar22Bright
Apr16Bright
May6Gloomy
Jun1Gloomy
Jul1Gloomy
Aug0Gloomy
Sep2Gloomy
Oct11Mixed
Nov18Bright
Dec19Bright

Humidity comfort

DryComfortableHumidMuggyOppressiveMiserable

Share of days at each humidity comfort level, based on the dew point — the measure that tracks how muggy it actually feels.

Humidity comfort is graded by the dew point — the temperature at which the air would be fully saturated — because it tracks how muggy it actually feels far better than relative humidity does. A low dew point feels dry and crisp; a high one feels sticky and oppressive no matter the reading on a humidity gauge.

In Nan, how humid it feels changes dramatically over the year.

The more humid part of the year lasts 8.4 months, from around March 17 to November 26. The muggiest month is April, when the air feels humid, muggy or worse about 100% of the time.

The most comfortable stretch runs from around November 27 to March 16, and February is the most comfortable month — the air is dry or comfortable 41% of the time.

0%10%20%30%40%50%60%70%80%90%100%JanFebMarAprMayJunJulAugSepOctNovDecFeb 4 · 46%Apr 19 · 0%miserablehumidoppressivemuggycomfortabledrycomfortablehumidcomfortable
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
Jan935431110
Feb832431610
Mar112344390
Apr00535581
May00047125
Jun00004852
Jul00004555
Aug00004258
Sep00014455
Oct013117114
Nov262240300
Dec1024392340

Wind

Average wind speed through the year, banded into plain-language speed zones so a number reads as 'breezy' or 'calm' without knowing the scale.

This is the average sustained wind speed at the standard 10 metres above open ground — the steady flow a weather station reports, not the sharper gusts that come and go, which can run half again as fast. It's the number that says whether a place is generally breezy or calm.

Wind in Nan is steady company: average speeds sit near 4 km/hcalm — in every month of the year, with no meaningful windy or calm season.

0510JanFebMarAprMayJunJulAugSepOctNovDeccalmJun 21 · 6 km/hOct 6 · 3 km/h
Wind speed (km/h)Feels
Jan4calm
Feb5calm
Mar5calm
Apr5calm
May5calm
Jun5calm
Jul5calm
Aug5calm
Sep3calm
Oct3calm
Nov3calm
Dec4calm

Hazard calendar for Nan

In seasonPeak

When the seasonal hazards worth planning around — the rainy season, tropical-cyclone risk and dust haze — are active through the year.

Nan's monsoon runs May–September, when most of the year's rain falls.

Monsoon
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Best time to visit Nan

TravelBeach/poolTemperatureCloudsPrecipitation

To characterize how pleasant the weather is in Nan throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.

Around late January, Nan is still near the tail of its best-weather window — great conditions with the peak-season crowds already thinning.

Inferred from the travel-score curve; month-by-month visitor numbers are a planned addition.

The travel score favors clear, rainless days with daytime highs between 18°C and 28°C. Based on this score, the best time of year to visit Nan for general outdoor tourist activities is from late November to early February, with a peak score in the last week of December.

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timebest timetravel scoretemperaturecloudsprecipitationDec 24 · 7.0

The travel score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

Travel score (0–10)Rating
Jan6.4good
Feb4.7fair
Mar3.0poor
Apr2.2poor
May2.3poor
Jun2.5poor
Jul2.6poor
Aug2.6poor
Sep2.8poor
Oct4.1fair
Nov5.4fair
Dec6.6good

The beach/pool score favors clear, rainless days with daytime highs between 24°C and 34°C. Based on this score, the best time of year to visit Nan for hot-weather activities is from late October to early March, with a peak score in the last week of December.

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebest timebeach/pool scoretemperaturecloudsprecipitationDec 23 · 8.9

The beach/pool score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

What to pack for Nan, by month

EssentialRecommendedOptional

Month by month, what's worth putting in the bag — from the temperature range, rain chance, sun and wind. Tap a month for a quick packing note.

For a warm-season trip around April (highs near 36°C), the essentials are light clothes, rain gear and sun protection. In the cold season around December (highs near 29°C), pack light clothes.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In April, Nan sees daytime highs around 36°C and nights near 24°C. Pack light clothes and sun protection. Worth having: rain gear. About 12 days see rain.

UV index (midday) in Nan by month

LowModerateHighVery highExtreme

Clear-sky midday UV index through the year, shaded by the WHO exposure levels — how much sun protection each month calls for.

Under clear skies, the midday UV index in Nan peaks around August 12 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 17 at about 7 (very high).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecVery highExtremeVery highAug 12UV 13Dec 17UV 7
UV index (midday)Level
Jan8Very high
Feb9Very high
Mar9Very high
Apr10Very high
May11Extreme
Jun13Extreme
Jul13Extreme
Aug13Extreme
Sep11Extreme
Oct10Very high
Nov8Very high
Dec7High

Average hourly UV index in Nan

LowModerateHighVery highExtreme

Modeled clear-sky UV for every hour of every day — when in the day sun protection actually matters.

The whole year hour by hour: each column is a day, each row an hour, and the color is the modeled clear-sky UV index — the midday peak scaled down as the sun sits lower in the sky. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.

UV falls off far faster than brightness as the sun drops, so even in August the burn window is concentrated in the middle of the day: about 8.5 hours a day reach index 3 (protection recommended), and 6.5 hours reach 6 or more. Mornings and late afternoons stay comparatively gentle year round.

JanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AM
UV ≥ 3 (h/day)UV ≥ 6 (h/day)
Jan6.54
Feb74.5
Mar74.5
Apr7.55.5
May86
Jun8.56.5
Jul8.56.5
Aug8.56.5
Sep7.55.5
Oct75
Nov6.54
Dec63

Air quality in Nan by month

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see which months the air is worst, not just the yearly average.

Air quality in Nan is worst in March — around 71 µg/m³ PM2.5 (unhealthy), about 4.2× the cleanest month (September, 17 µg/m³).

Seasonal pattern from CAMS reanalysis, scaled to Nan's WHO annual average of 29.5 µg/m³.

020406080JanFebMarAprMayJunJulAugSepOctNovDecModeratePoorUnhealthyModerateMar 2270 µg/m³Sep 1517 µg/m³
PM2.5 (µg/m³)Level
Jan27Moderate
Feb39Poor
Mar71Unhealthy
Apr65Unhealthy
May28Moderate
Jun17Moderate
Jul17Moderate
Aug17Moderate
Sep17Moderate
Oct17Moderate
Nov18Moderate
Dec21Moderate
Almanac & agriculture

Growing season

Chance of a frost-free dayFrost-free year round

Nan is frost-free year round — even the coldest nights rarely reach freezing, so there is no start or end to the growing season.

0%25%50%75%100%JanFebMarAprMayJunJulAugSepOctNovDecfrost-free year round
Frost-free chance (%)Frost nights
Jan1000
Feb1000
Mar1000
Apr1000
May1000
Jun1000
Jul1000
Aug1000
Sep1000
Oct1000
Nov1000
Dec1000

Growing degree days

Degree days (base 10°C)Frost-free shaded

Growing degree days tally heat above 10°C: each day adds however many degrees its average temperature runs over that threshold, and cold days add nothing. Nan banks about 6,116 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around April.

02,0004,0006,000JanFebMarAprMayJunJulAugSepOctNovDec
Growing degree days (°C·days)
Jan402
Feb418
Mar551
Apr587
May591
Jun554
Jul550
Aug539
Sep523
Oct525
Nov465
Dec410

Solar energy

Average daily shortwave solar energy reaching the ground, banded into brightness zones so the number means something at a glance.

Solar energy is how much sunlight actually reaches the ground each day, measured in kilowatt-hours per square metre (kWh/m²) — the combined effect of how long the sun is up, how high it climbs, and how much cloud gets in the way. It's the raw fuel a solar panel has to work with: for scale, 1 kWh/m² a day is dim and wintry, while 7+ is desert-bright.

Nan receives about 4.8 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 3.8 and 6.2 kWh/m².

The brighter stretch of the year lasts 4.3 months, from around Jan 24 to Jun 2. The brightest month is April, averaging about 6.2 kWh/m² (intense).

The dimmest month is August, down near 3.9 kWh/m² — roughly 37% less than the April peak.

01234567JanFebMarAprMayJunJulAugSepOctNovDecbrighterdimmerdimmoderatebrightintenseApr 106.2 kWhAug 43.8 kWh
Solar energy (kWh/m²)Level
Jan4.6Bright
Feb5.4Bright
Mar6.1Intense
Apr6.2Intense
May5.3Bright
Jun4.5Bright
Jul4.0Bright
Aug3.9Moderate
Sep4.2Bright
Oct4.6Bright
Nov4.5Bright
Dec4.4Bright

Where is Nan?

Nan sits at 18.8°N, 100.8°E, 205 m above sea level, in Thailand. The nearest listed city is Dok Kham Tai, 93 km away.

Dok Kham TaiPhraePhayaoDen ChaiLampangUttaraditChiang RaiBan Houakhoua

Topography around Nan

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Nan.

Within 3 km, the terrain around Nan has only modest variations in elevation — a maximum elevation change of 61 m around an average of 208 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 478 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,915 m.

The land around Nan is covered by trees (39%), artificial surfaces (28%) and cropland (21%) within 3 km, trees (76%) within 16 km, and trees (87%) within 80 km.

3 km
61 m
16 km
478 m
80 km
1,915 m
treesgrasslandcroplandartificial surfacesbare terrainwater
Nearby: Dok Kham Tai 93 km · Phrae 98 km · Phayao 105 km · Den Chai 117 km · Lampang 146 km · Uttaradit 148 km · Chiang Rai 160 km · Ban Houakhoua 166 km

Thailand travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type A / B / C
230 V · 50 Hz
Prices
≈ 31% of US
price level, 2025
GDP per capita
$8,057
2025
Happiness
6.3 / 10
World Happiness, 2025
Homicide rate
4.8
per 100k, 2011
Road deaths
32.2
per 100k/yr, 2019
Income group
Upper middle
World Bank
English
Very low
EF EPI 402
Religion
Buddhist 93%Muslim 5%Christian 1%other 1%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Nan (18.7838°, 100.779°, elevation 205 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).