I’ve just been looking back at the rainfall statistics for Cape Town which as you probably know is suffering its worst drought since at least 1933. They knock out a good SYNOP at Cape Town international airport, so it wasn’t that difficult to add up the 24 hour rainfall totals to find that in the last 12 months 266.2 mm of rain has fallen there (fig 1). That doesn’t sound too bad on the face of it, but in the last five months, that’s since the start of November, there has been only 51.7 mm of rain.
The climate here is pretty equable as you can see from the six hourly temperatures for the last year (fig 2).
Apparently Day Zero, the day when water runs out completely, and which was expected to occur this April, has now been pushed back to 2019. Let’s hope (no pun intended) that the 6 mm of rain that fell in the last week is an omen of a wet winter to come for Cape Town’s sake.
In view of the drought conditions in Italy, I thought that I would look back at the rainfall during the last month. It’s not 100% accurate because of missing observations from some stations. Rather surprisingly I did find some accumulations, not a lot, and probably not enough to halt the drought, but there has been some. Let’s hope there’ll be more in the coming months.
I thought I would just look at the SYNOPs for Rome’s Fiumicino airport since the start of the year and see how severe the drought that is that’s been affecting that part of Italy, and by the look of things it’s very severe indeed. The total rain I have found from the available SYNOPs is 131.4 mm (fig 1), which is not a lot in almost seven months, and according to the observations that I have the last 24 hour rainfall they reported was 4.6 mm on the 29th of June.
According to the Wikipedia article on the climate of Rome, the average rainfall from January to the end of July at the airport is 341.6 mm, so in 2017, there has only been a little over 38% of the average rainfall (1971-2000 long-term average). So it’s no wonder that the Guardian reports that all the fountains in the Vatican City were turned off on Monday of this week. And the reason for the drought? The bulk of annual rainfall in that part of Italy falls outwith the Summer months, but during last winter and spring the mean pressure across Italy and the Alps was much higher than average, this limited the number of depressions and rainfall events to affect that part of Italy. If I remember the Adriatic was quite stormy at times during the Winter, but the rain probably fell on the east coast and the Apennines and didn’t make it across to the west, well that’s my best guess anyway.