All climate research of Mali Lošinj undoubtedly starts with the work of Ambroz Haračić, professor at the Nautical school in Mali Lošinj at the end of the 19th and beginning of the 20th century, when Mali Lošinj was an important research centre on the Adriatic. Professor Haračić defined all the characteristics of Lošinj, especially in relation to various localities on the Adriatic and the Mediterranean. Climate research of the island of Lošinj was, at that time, of crucial importance, in that in 1892 Veli and Mali Lošinj became climatic spas, which opened a new economic realm – tourism.

The main characteristic of the Mediterranean climate are light winters and not too hot summers. The island of Lošinj is far enough from the coast, so that the sea has a dominant influence. The sea does not warm up as fast as the coast, but looses warmth much slower, so that during winter times the sea is the reservoir of warmth that heats the air. Consequently, winters are lighter and warmer then on the coastal part of Primorje region.

This specific maritime climate is seen also in its lessening of the summer heat, so that Mali Lošinj has noticeably less days with the maximum temperature higher then 25 °C. Based on the temperature characteristics and the micro-climate Mali Lošinj is similar to the places on the Cote d’Azur (Cannes, Nice), while from San Remo, Krf and Palermo it has 1 to 2 °C higher average temperatures.

Sea temperatures throughout fall, winter and first days of spring higher then air temperatures. The cooling effect of the sea is appreciated during the hottest days of the year. If we take that the sea temperature of 20 °C is pleasant for bathing, then the bathing season in Mali Lošinj could last up to 126 days, from the first week in June to the second week in October.

Sunny days are also one of the most important characteristics of the climate of Lošinj. Average number of yearly sunny hours is 2580. Based on the number of sunny days Mali Lošinj is comparable to North African cities and parts of the southern Adriatic, element of sun exposure is of greatest importance for the tourists, which makes it a determinant element for choosing a vacation destination.

September, November and December have most rainfalls, while there is least in April and August. Mali Lošinj has relatively high average of rainfalls in a year, which is good for the air purification, diminishing of carbohydrate acid and stabilization of air. This is most important for places that function as spas.

Snow is extremely rare in Lošinj, because air temperature rarely falls under 0 °C.

The northeastern wind is the strongest and it hits mostly the east coast of the island. The south wind or the refreshing landward breeze usually hit the west coast of the island. The northeastern wind, the south wind and the landward breeze are typical of the Primorje. The frequency of the northeastern wind is highest during fall, winter and spring. The north wind is strongest in January, while the south wind dominates during the fall.

Because of the afore mentioned position of Mali Lošinj in a closed harbour with south-western orientation, with the background of high vegetation that protects the island from the Velebit range, the influence of the north wind is not felt in the town. The entrance to the harbour, next to the bays of Čikat and Krivica, is completely protected, so that even during the strongest north winds, walking is possible in that part of the island. On average Mali Lošinj has 118 days of total calmness without winds.