My wife and I are considering travel in Spain during the month of September. Most of first week would be in Lisbon, then a couple of days in Segovia then on to Ronda/Arcos area the balance of the second week, Seville/Toledo/Madrid area the third week, and then 3 or 4 nights in Barcelona. What daytime temperatures should we expect, would it be too hot, and would we be better off starting our trip in the middle of September and go to the middle of October? Of particular interest was the Feria de Pedro Romero Festival in Ronda that starts the end of the first week of September, which was why we are considering this time and itinerary of travel.
October is the month we always travel to Spain as the temps are excellent and crowds less.
However, September offers manageable temps and you have an excellent reason in visiting Ronda. So go!
France is a big country.
Go to Wikipedia and put any city's name in at the top right of the page. Scroll down and you'll find a chart on the city's statistics--including average daily high and low temperatures. It also says average monthly precipitation and average days that they have precipitation.
For historical day-by-date temperatures going back a number of years, which is the best way to determine the range of weather you might experience, go to wunderground.com, choose More > Historical Weather, enter one of your destinations, enter a date within your travel period and 2016, 2015, etc.. Then click on "View" and scroll down on the "Monthly" tab for a graph showing temperature.
Edited for specificity and clarity.
You seem to be zigzagging (time consuming and expensive) to get to Ronda. Why go to Segovia, then south to Andalucia, then back north to Madrid/Toledo?
Maybe you could fly into Malaga and start in Ronda? You could then go through Andalucia and north to Madrid/Toledo/Segovia, fast train to Barcelona and fly to Lisbon at the end, if the Feria is a high priority. By the way, according to this site the festival begins at the end of August this year.
My last five trips to Spain have all been during the month of October. I find the weather/temps to be very pleasant at that time of year and the crowds of tourists manageable. Rarely do I have to wait in line to see anything, and when I do the line is a relatively short one. I was in Cordoba, Sevilla and Ronda this past October (2016) and the high temps were in the mid-80's.
The Feria de Pedro Romero Festival in Ronda is listed Aug 28 to Sep 4 this year.
http://www.ayuntamientoronda.es/component/ohanah/feria-de-pedro-romero
I would order like this...
via Seville/Malaga to Ronda, then Arcos, before returning to Seville
Madrid (Segovia & Toledo)
Barcelona
Lisbon
If it's hot, then so what, it's Spain, it gets hot.
Agree with Changing about your zigzagging. Maximize your time seeing things and minimize the travel between places. Do Sevilla, Ronda, and Arcos, then do all the places near Madrid. It can still be very hot in southern Spain in September. I spent two weeks in early September in southern Spain in 2014 and it was miserablely hot (we just happened to be there during g a heat wave) We were more in the area of Granada, Almeria, Murcia for most of the trip, but we're also in Toledo, Cuenca, and Madrid.