April, May, June, September and October are the easiest months, with highs between 16 and 26 degrees and shorter queues than in high summer. July and August average 28 degrees, and the terraces and baths fill up. December is busy with Christmas markets, and January and February are cold, with highs of 3 to 6 degrees.
Best months: April to June and September to October
Highs rise from 11 degrees in March to 23 in May. May has the most rain days of the year, about eight, and the parks and Margaret Island turn green.
What to wear: Pack layers and a light waterproof jacket.
Summer
16 to 27 °C · about 7 rainy days a month
June to August highs run from 26 to 28 degrees, with warm nights around 15 to 17. Hot spells can push highs above 34 degrees, and there are five to eight rain days a month.
What to wear: Wear light cotton, a hat and shoes that grip on the steep hill streets, and pack a swimsuit for the baths.
Autumn
7 to 16 °C · about 6 rainy days a month
September is still warm at 23 degrees, October cools to 16 and November to 9, with about seven rain days. The light fades early from late October.
What to wear: Bring a jacket, an umbrella and warmer layers from late October.
Winter
-1 to 4 °C · about 6 rainy days a month
Highs sit between 3 and 6 degrees and nights fall below freezing from December to February. There are six or seven wet days a month and the daylight is short, which suits the baths.
What to wear: Wear a warm coat, a hat, gloves and shoes with grip for icy pavements.
If it rains
Rain does not stop a visit to Budapest, because the thermal baths work well in wet weather. The Parliament, the National Museum, the House of Terror, the Basilica, the Synagogue and the Opera are all indoors, and the Great Market Hall is a covered stop. Keep Castle Hill, the bridges and Margaret Island for a dry spell.
July and August highs average 28 degrees, with some days well above that. Do Castle Hill and the Gellért Hill climb in the morning or the evening, and use the afternoon for the baths, the museums or the market hall. Carry water, because the bridge and the Bastion terraces have little shade.