Meteo Medan (Sumatra) in luglio

July sits in North Sumatra's drier half - the wet season runs November to the end of April - and the forum's description of what falls is the useful part: mornings are normally sunny, showers come in the late afternoon or early evening, and they rarely last more than an hour or two. Lake Toba also gets off lighter than Medan, where it rains often and heavily. Our own row is wetter than the seasonal label suggests - 23.1 precipitation days carrying 174.8mm - which fits the pattern of a short shower most afternoons rather than settled grey. Samosir, out in the lake, is where most people stay for the Batak villages. The rest: 26.5C days that feel like 31C, 21.4C nights, 9.4 hours of sun, AQI 37.

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.