What makes northern Italy so hot in summer?

[Derek41]

Summers do appear warm, but it also lacks the pronounced seasonal lag of a classic Mediterranean climate, and temps do not stay notably warm into the 2nd half of autumn - which you would expect at this latitude.
So overall, not remarkable for it's location.

[nei]

Portland has slightly cooler summers at the same latitude as Milan. Same annual mean:

Portland, Oregon - Wikipedia, the free encyclopedia

[WhiteWalls]

I live near Bologna and I always thought we have a climate that's a bit deceptive and the climate box doesn't tell you everything.

It's obviously hot in summer because of close to sea level elevation, sheltered position, no significant bodies of water nearby (there's the adriatic, but it's so shallow it almost does not make a difference), but still very much affected by saharan heat waves.

I think our summers are hotter than they seem for two reasons:
First, the 30C average high is a bit deceptive because summer precipitation takes temperatures down a lot for a few days, so the "usual" average high when it's sunny (most of the time) is more like 33-34C. Then a couple of days of low pressure can bring it down to 20C easily.
Second, there very little wind which makes the air feel more suffocating, as it's also humid sometimes.

But still I think our summer climate is nothing exceptional for our latitude, just a bit more continental than the rest of Italy as it should be. It's a unique topography in Europe, which leads to a more extreme climate than other places.

[Troms]

Low altitude, distance from the sea (the Adriatic sea is quite close, but it is too small to really play a moderating effect on Milan), the presence of the Alps shielding the plain from the cool winds of the Atlantic Ocean, subsidence due to the peculiar "arc" position of the mountains, almost no wind, heavy urbanization which keeps nighttime temperatures high. But, as others said, I don't find it particularly notable (although I do personally find it unbearable especially for the high humidity during night and consequent mosquitoes, but it is not the only one ).
WhiteWalls is right: the peculiar topography of the area makes that area a little more continental than what would be expected for that geographical position, but still nothing really extreme.


By the way, I still do not understand the widespread opinion that all the places at a given latitude should share the same climate. I do not find it surprising if at a certain latitude some places are warmer (or cooler) than others. I believe that latitude as a climate factor should be taken into consideration very carefully and mostly on a local scale.

[Qilin34]

Karamay, Xinjiang at 45° 36' N likely takes the cake for hottest summers poleward of 45°