I'm traveling to France and the UK the end of Sep thru 1st week of October. I don't know what to expect with weather wise and wonder if weather should determine whether I visit Paris first and visit the UK last or vice versa? Any suggestions? Thanks.
Here is a link to weather underground that shows you the weather from last year:
Paris Sept 2015:http://www.wunderground.com/history/airport/LFPO/2015/9/20/MonthlyCalendar.html?req_city=Paris&req_state=&req_statename=France&reqdb.zip=00000&reqdb.magic=37&reqdb.wmo=07156
I don't think that either order will make much difference, really. It's impossible to predict the weather in any given week in any given place 6 months out, and the difference in temps/precip. over the spread of just two weeks either may or may not vary much. For instance, over the past two weeks where I live we've gone from 60's/70's and sunny to grey skies, snow and 30's. Neither possibility could have been predicted more than a week or so in advance.
I also don't think the order of your travels matters either. Best advice I can give is to check the weather a week or 10 days before you leave, so you'll know what to pack. I was in London in mid-September 2012 and again this past October. Both times, it was rainy and chilly. In fall 2012 the UK experienced one of the wettest autumns on record. I wanted to go to York for a day but there was flooding in northern England so I went to Canterbury instead. It rained there that day too.
When we travel we usually go mid sept to mid October. Last year we did France very end of sept and first few weeks of October. We were in Nice during that second week and it was so hot I had sweat running down my back. We were in London a few days before coming home and the weather was fine with a light coat. Evenings were cool in Paris but a light jacket sufficed.
Then again, in 2012 we went from the south of France near the end of sept where it was hot. Made our way to the north of France where it was much cooler. Over to the UK and We had to buy fleece pullovers because we were too cold with only our light jackets.
Now, I'm used to Nova Scotia weather, so anything over 25 Celsius is really warm for me, and I'm even comfy in a light jacket at about 15c. What climate are you used to? If you are from California or Texas you may feel cooler temps different from others.
I don't think you will find a huge difference between where you start. If you were really worried, start in the uk first. I will say we usually hit the jackpot weather wise when we travel mid September to mid October. Mostly sunny skies, warm days, cooler evenings and the odd day of rain.
It's usually pretty nice in Paris that time of year. Can definitely swing slightly warm in the day and cooler at night, but generally speaking it's one of the better times of year weather-wise. If you pack for a couple of warm days (in the 80s, which may not sound that warm, but remember no A/C most places, and it's humid...) and a couple of cool/rainy days, and you'll be fine.
I was in the UK/France through all of October 2015 and had absolutely glorious weather for the entire trip, less 2-3 days of light drizzle in London and Cardiff. Even Scotland was grand weather-wise (no rain at all, a bit chilly mornings, beautiful afternoons). Paris at the end of October was like early summer in both temps and sunshine. I ended up carrying rather than wearing my light rain jacket in the afternoons.
I don't think it matters - in both cities, it will be damp, it will rain some of the time, it could be a little chilly in the morning or late afternoon/evening, or there might be a short warm spell. Nothing you can't handle if you bring appropriate clothing. You will not need rain boots or heavy coats. Something waterproof with a hood and an umbrella would be important.
Both the UK and Paris are in areas where the weather can - and will - change at the drop of a hat. The meteorologists in both countries are wrong 90% of the time.
There's no point in asking about historical data or what happened on someone's trip in the past, because the weather is not what it used to be.
In Paris, we've had a very mild, wet winter, so the trees might turn color later than usual - probably in late October.