Medan (Sumatra) weather in January
January in Medan: sweltering, soaked, with muggy air — a gamble, with 24 rainy days.
Updated September 2026 · climate normals from ERA5 reanalysis
#3 of 12 months in Medan · #1004 of 1413 destinations to visit in January · comfort 58/100 (tier D)
- Days
- 31°C
- Nights
- 23°C
- Wet days
- 24
- Sun
- 8.8 h
- Humidity
- 88%
- Daylight
- 12 h

Traveller notes on Medan in January
Notes from nearby Lake Toba (107 km away)
Medan doesn't have its own notes for January yet — these are about Lake Toba, close enough to share the season.
Lake Toba-forum threads on how rainy late January runs describe this as genuinely within the wetter stretch, posters calling September through January the period of higher rainfall regionally. Regulars call the typical pattern an intense late-afternoon or overnight shower rather than all-day rain, some days passing with nothing at all. Posters describe one long-resident's account of early January as genuinely the worst stretch, persistent drizzle and cold for days straight, while a later system dropping real volume was barely noticed since it arrived in the evening and cleared by morning. Regulars call daytime temperatures reliably warm regardless of the pattern, dropping only modestly overnight. Posters recommend a longer local forecast rather than a single day's reading. Regulars call the lake worth visiting regardless of the wetter season's reputation. The record: 24.7C days feeling like 29C, 20.7C nights, an extraordinarily high 256.8mm across over 27 days and 87 percent humidity.
Other months in Medan
Forum posters describe the broader Indonesia dry season, roughly June through August, as generally recommended for travel, though posters note rain remains a near-constant presence across the archipelago's calendar rather than disappearing entirely - a full day of nonstop downpour is unusual, with more typical patterns being a few hours of passing rain followed by sunshine again. It is worth noting that for Medan specifically, the full 12-month climate record shows August is not actually among its driest months - January and February run noticeably drier here, with rain staying elevated from April through December. Posters consistently recommend packing rain gear regardless of the season given how unpredictable North Sumatra's weather can run. Posters generally rate August as warm and genuinely rain-prone for Medan, the wider Indonesian dry-season framing not holding up well for this particular city.
Forum posters describe February as still squarely inside the region's rainy season, with daily rain a real possibility running well into the following months - though posters note February is generally a bit drier than January, even as climate patterns have grown less predictable in recent years. For Medan and North Sumatra specifically, posters describe conditions as genuinely unpredictable day to day, recommending flexibility built into any itinerary through Lake Toba and Berastagi rather than counting on a dry stretch. Posters contrast this with parts of eastern Indonesia like Lombok and Komodo, which tend to run drier at the same time of year for anyone able to adjust their route.
Add your own note from Medan's card on the map.
Medan climate normals — January
Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.
Crowds in Medan in January
How busy the place itself is — school and mass holidays, the months an editor tagged, and how sought-after the weather makes them. Never part of the comfort score.
Peak crowdsChinese New Year, Christmas and New Year, Year-end break in Indonesia(estimated)
Peak crowdsBusyShoulder seasonQuiet
Best months for Medan's weather
Ranked by this destination's own climate comfort score across the year — a different thing from how busy it gets (see Crowds above).
Best weatherMedan's weather peaks January–March, best around February.
Best weatherFair weatherToughest weather
What's on in Medan in January
Recurring seasonal events, natural spectacles, closures and holidays — curated and sourced.
- Hazard
Sinabung ash and alerts
1 Jan – 31 DecVolcanic activityClosuresThe volcano above Berastagi, two hours up the road, has spent years at raised alert with an exclusion zone around it. Ash falls close the Karo highland roads and occasionally the flight paths. Source ↗
- Holiday
Chinese New Year
20 Jan – 25 Feb · usuallyLunar New YearClosuresMedan has one of Indonesia's largest Chinese communities and the temples on Jalan Zainul Arifin run day and night for it. Much of the city's food trade closes for two or three days. Source ↗
- Holiday
Christmas and New Year
18 Dec – 5 JanChristmas & New YearCrowdedBook earlyNorth Sumatra's Batak population makes Christmas a bigger holiday here than in most of Indonesia; the churches are full and the road to Toba is booked out. Source ↗
- Season
Wet season
MonsoonRisk24 rainy days and about 216 mm in the month — the real kind of rainy season, not afternoon showers.
from the climate normals
Nearby, and something's on
Within 300 km of Medan — a day trip or a short hop — with something on this month. Never part of the comfort score.
Where is Medan?
Medan in January — FAQ
- Is January a good time to visit Medan?
- January in Medan: sweltering, soaked, with muggy air — a gamble, with 24 rainy days. It ranks #3 of 12 months for Medan on SeasonMap's comfort score (58/100).
- What is the weather like in Medan in January?
- In January, Medan averages a daily high of 30.9°C and a low of 23.4°C, with about 216.3 mm of rain over roughly 24.3 rainy days.
- What is the air quality in Medan in January?
- Medan has a mean US Air Quality Index of about 77 in January.
Within 300 km: Penang's Thaipusam around 20 Jan – 15 Feb, and Lake Toba's Batak Christmas on 15 Dec – 5 Jan.