Lima — sää kuukausittain

The city is in a valley surrounded by an extremely arid desert, receiving on average no more than 3 cm of rain per year. The city is surprisingly green with many parks and trees, but all of them are artificially watered by the municipality! In the summer months, December to February, the weather is usually sunny and hot, with a UV index that is invariably extreme. Even a layer of factor 50 sun block won't offer protection for long, and it's recommended to stick to shaded areas as much as possible, which is problematic when visiting archaeological sites in the scorching sun. The rest of the year, the weather in Lima is overcast, and temperatures are between 20 - 30 C° during day time, which seems chillier when combined with the general dampness. Air pollution in the streets of Lima can be very bad due to a combination of weather and older poorly-maintained vehicles.

Lima forum threads consistently name January through March as the city's warm, sunny summer stretch, with daytime temperatures typically in the low-to-mid 20s Celsius, sometimes higher, but posters were clear that high humidity can make the heat feel noticeably heavier than the number alone suggests. A recurring theme: January is genuinely the best time to see Lima clearly, since the persistent grey fog (garúa) that blankets the coast through the cooler June-to-August winter largely lifts in summer, leaving far better visibility for sightseeing. Posters framed January and February as prime season here specifically because it pairs with the dry, sunny window for nearby desert destinations like Paracas and Huacachina, even as the same months bring the rainy season to the Andes further inland. The standard packing advice was light, breathable cotton clothing suited to the humid warmth.

Lima forum regulars call February genuinely good coastal weather, the reverse of the highland pattern: warm temperatures averaging around 70 to 80 degrees during the day, with great weather in February — nice and warm in Lima compared to other parts of Peru this time of year. February is Peruvian summer, beach season on the coast, while the same month brings the rainy season to the highlands — Cusco and Machu Picchu specifically named as the wetter counterpart. High humidity is the honest catch on Lima's own warmth, can make the heat feel very uncomfortable, loose cotton clothing the standard recommendation. Our record: 26°C days, 21.1°C nights, 10.4 rain days, 83.1% humidity and a 21.2°C sea — warm, humid and swimmable, matching the “coastal summer, opposite of the highland wet season” read.

Regulars are specific that the city's famous garua, the thick grey mist that hangs over Lima for much of the second half of the year, hasn't properly settled in by this point - visitors report going a full trip in mid-May without seeing it at all, since the fog's main season runs June through December instead. Our row backs a still-mild, largely dry month, 22.9C reading as 25C, over 17.8C nights, with rain nearly absent at 2.8mm across under a day - Lima's coastal desert climate produces almost none of its own rain even at the wettest point of the year. Humidity stays notably high, 82 percent, even without the visible mist, a preview of the damp grey stretch still to come. The sea sits at 22.3C. The record: 10.5 hours of sun, a 12.5 kph wind and AQI 46.

Regulars name a specific local phenomenon, the garua, as the defining feature of this month - a damp, cold, low-lying maritime mist that hangs over the city and makes surfaces genuinely slippery, all without producing anything that counts as real rain. Our row backs that grey, misty read, 20.6C over 16.5C nights, with essentially no measurable rain, 1.4mm and zero rainy days recorded, alongside humidity at 77 percent, consistent with mist rather than rainfall driving the dampness. Regulars are consistent temperatures rarely climb above 20C for the full stretch this typically continues, a genuinely different Lima than the sunny coastal city many expect. A proper waterproof jacket is the standard advice despite the near-total absence of actual rain. The record: 10.6 hours of sun, a 12.7 kph wind and AQI 47.

August is garúa season and the forum is blunt about it: Lima sits under a thick grey coastal fog for much of the year and August is the thick of it — cold, damp and grey rather than wet. That is why the rainfall figures here look so low; garúa is a maritime mist that soaks everything without ever really raining. Temperatures stay mild, near 21°C by day and 15 at night, and posters say the sun feels warm when it does break through and you can still eat outdoors. Bring a fleece and something waterproof. One local tip worth having: drive 100km up or down the coast and it is usually clear.

Lima earns its nickname, la Gris, from the garua - the cold damp mist that sits over the city for much of the year - and October is the month it lets go. Regulars say the early part can still be overcast and the later part brightens, with winter effectively gone by September and October and November warm and bright without being hot, around 16 to 23C. Our row lands inside that at 21.7C over 16.7C, with 11.4 hours of sun and rain that is barely there at 4mm across 1.2 days. Humidity stays at 79 percent all the same, which is the point about this coast: the moisture arrives as mist, not as rain. The record: a 13.4 kph wind, an 18.5C sea and AQI 39.

November is when Lima starts to come out from under the garua - the thick grey coastal fog that sits over the city from about June to December - and regulars describe blue skies, brighter days, lower humidity and pleasant temperatures arriving now, with late-November visitors usually lucky and occasionally still greyed out. The clear run is December to April. Our row gives 23C days over 17.9C nights at 79 percent humidity, and almost nothing falling: 3.4mm across 0.8 precipitation days, because the garua is fog rather than rain and our dataset cannot see it. The sea stays cold at 18.7C. The record: feels-like 25C, 11.4 hours of sun and AQI 43.