It is the 9th of August of 2011, and I am on a plane heading to (west) Crete for my summer holidays, so my access to data is limited, but here are some thoughts on hot summer weather in Crete: how are temperatures this summer on the island and how do they compare to other years?
Looking at the data from the beginning of the summer until now, one can easily realize that Cretans and visitors of Crete have not experienced anything dramatic so far. Temperatures have, of course, been summery (with June being somewhat cooler than average and July being somewhat warmer), and rain on the island has stopped since June, but the highest temperatures that the island has experienced this summer have mostly been in the vicinity of 37-38°C, which is far from being severe for a place located in the Mediterranean area. And this is not an anomalous situation: e.g. I was supervising the meteorological station of the Technical University of Crete (near Chania) for two summers (2003-04), and the highest temperatures I recorded were, again, around 37-38°C.
However, this is not the case every summer, as there have indeed been years when temperatures climbed to 40°C, and sometimes exceeded it. An extreme summer was that of 2007, when drought and heat were pretty persistent and caused problems throughout Greece, such as the tragic fires in the Peloponnese. During that summer, 43-45°C had been reached in Chania even in June, and there was also a significant heat wave in July.
What is it that makes the summers more or less hot than average?
Well, this is a big discussion, but in a nutshell we can say that the broader atmospheric circulation patterns (i.e. how the atmosphere moves on large spatial scales) that dominate each summer play a major role. If, for example, they favour the formation of persistent “meltemi” (northerly) winds , which can blow over the Aegean for several weeks during the summer, the island is kept cooler, with only the southern coasts potentially experiencing heat. The northern coast of the Chania area is blessed by a quite frequent occurrence of meltemi, but somewhat less than the Cyclades or eastern Crete (e.g. Heraklion). The latter can be more windy, almost too windy at times, but also even cooler on days of meltemi (August 13th note: the weather that Crete has been experiencing since Thursday is a typical meltemi situation, with cooler temperatures and even some cloudy/rainy weather; the latter conditions are fairly unusual for July/August in Crete, but they have been experienced before, and were even more pronounced in July 2002, when the island experienced several thunderstorms, a phenomenon that is associated more with northern Greek summers).
Can we predict these broad circulation patters as early as e.g. the beginning of the summer, so that we will know in advance how the summer will evolve?
The answer is that it is pretty difficult, since seasonal forecasts are highly uncertain. Maybe in some decades from now it will be more possible, but not now… Until then, go ahead and enjoy the current not-so-hot summer. And don’t pay much attention to street thermometers and TV news, which usually tend to overestimate/overstate anything that has to do with heat!
PS: For typical summer temperatures in coastal northwestern Crete, please follow this link.