Weather Thessaloniki
Thessaloniki sits in the North East of Greece, the capital of Macedonia and the second largest city in all of Greece. With over one million in habitants it is also one of the largest cities in all of Eastern Europe. Thessaloniki is located on the northern fringe of the Thermaic Gulf, near the Aegean Sea and bordering the Mediterranean. Its location lends its self to a Mediterranean climate, however its exact position sees it actually sitting in a transitional climate zone as during some parts of the year the city experiences weather conditions that are characteristic of a continental climate- however, the majority of the year sees Thessaloniki bask in an enviable Mediterranean climate. Rainfall across the year isn't excessive- annual precipitation is, on average, 451mm, with the wettest months being November and December. Rainfall is fairly well distributed across the year, only reaching minimum precipitation in the height of summer. June, July and September are the only months which record precipitation less than 30 mm.
Winter
A continental climate is one which sees greater temperature extremes and one which gets cold enough to support a small amount of snow cover. While snow fall in the city is very rare, most years do see at least a minimal amount recorded in the height of winter. During the particularly bad winters the mercury can fall to a bitterly cold -10ºC, however on the whole the average daily temperature from December to February is about 5 to 7 ºC- which is significantly colder than most other Mediterranean cities.
Summer
Summers in Thessaloniki see average temperatures of 23 ºC to 25 ºC, though temperatures over 30 ºC are not uncommon so be sure to pack sunscreen and light clothing if you're planning on doing some mid-day sightseeing. Rainfall during the summers is minimal and infrequent, and while temperatures can reach over 30 ºC they will almost never reach over 40ºC, so you won't be sweltering in the heat that Athens can see in the middle of summer.
Thessaloniki, Greece.
Autumn and Spring
Autumn and spring bring milder conditions to the region, the average temperature in March is 9 ºC before picking up to 18 ºC in May. Rainfall during spring is generally between 35mm to 45 mm and falls in light showers, though on the warmer days it can be accompanied by dramatic thunderstorms. Conditions in autumn are much the same, though rainfall is great as you move closer to winter so pack an umbrella and expect some rainfall. The city has been hit by 10 powerful earthquakes in its recorded history, with the most recent being the 1978 quake which saw the city rocked by an earthquake measuring 6.5 on the Richter scale- there hasn't been any as devastating since this though its position near a fault line means that it is at risk.