January is indeed the coldest month in Croatia with temperatures frequently reaching freezing or below with an average range between 32 and 47 degrees Fahrenheit.
Along the coast, the weather is a few degrees warmer than the interior of Croatia, though in the southern regions it is quite wet with about five to six inches of rain for the whole of the month. And there's also the strong, northeasterly winds of the bura to deal with. When the bura blows, people stay indoors, ferries are canceled, and bridges are closed. It's, therefore, a smart idea to pack a waterproof jacket and have warm layers on hand.
Inland, in the north and around Zagreb, you'll want to have proper winter apparel, a heavy coat, hat, scarf, and gloves because temperatures hover around freezing with highs of 37 degrees Fahrenheit and lows of a frosty 27 degrees. Snow is common over the winter months and because of that, traveling in highland areas is frequently disrupted.
Crowds & Costs
The Advent and Christmas crowds have long gone, returning Croatia to its off-season charm in January: quiet environs and budget-friendly accommodation prices. The Adriatic coast remains quiet, hotels reduce their prices if they aren't altogether closed, and ferries reduce their routes and travel times if they aren't canceled due to inclement weather. Ski season is in full swing, vacationers heading to the slopes, though unlike other more popular European destinations, Croatian resorts remain uncrowded and less costly.
Where to Go
Croatia in January offers a little something for all tastes. If you're escaping the cold, head to the Adriatic coast. Start in Dubrovnik, still decked in festive decorations for its Winter Festival (which runs until March), and you'll enjoy the near, if not empty, main attractions like the ancient city walls and sea views. Other coastal cities with noteworthy historic centers to explore in solitude are Split and Zadar.
Meanwhile, Croatia's interior and national parks, like Plitvice Lakes National Park, undergo a seasonal makeover looking like something out of a children's fairytale book enticing bundled-up visitors to explore its prepared-for-you routes. Zagreb, Croatia's capital, is likely covered in snow, which makes it a good time to head to the nearby ski resort, Sljeme just outside of town.
What to Do
Croatia might not be known for skiing like their European counterparts, but they are home to favorable conditions, milder weather, fewer crowds, and reasonably priced passes. One unique option is hitting the slopes of Platak in Primorje-Gorski Kotar County. Sitting six miles in from the sea and north of Rijeka, you can ski one of seven of Platak's slopes with a view of the Adriatic.
Another great option is to head to Sljeme Ski resort, just outside of Zagreb, for skiing, snowboarding, sledding, and even hiking. There's also the option to watch world-class skiing take place here every January with the Snow Queen Trophy (Snježna kraljica).
Meanwhile, party goers will want to make a trip to Rijeka come mid-January for Croatia's largest carnival. Here you can witness the ceremonious handing-over of the city key to the carnival "maestro" and watch how Rijeka's main street, the Korzo, transforms into a mass party. There are pageants, street dances, concerts, masquerades, and DJs spin at a variety of bars and clubs throughout the city.
Photographers and nature enthusiasts will love Plitvice Lakes National Park in January, transformed by the snow and ice adding a magical quality to the landscape. And foodies will have a much better chance of making a reservation at any of Croatia's top restaurants.
Events in January
New Years Day. A bank holiday you can expect nationwide closures and transportation schedules will be on a holiday schedule (if there's one running).
Night of the Museums. On the last Friday in January, galleries and museums across the country open their doors for free from 6 pm to 1 am and offer special programs, including hands-on activities, workshops, and exhibitions.