From the pictures it looks sunny and warm. Can you address what the weather was like for most of the cruise? Will have to pack light so don't know if I should take shorts, or jeans.
Good question disneymomto5:
The weather was one of the biggest hurdles we had with packing for this cruise.
Yes! sunny and warm on many days - high 60's / mid 70's . But it would also rise to 78 or drop below 60 at times and could rain at any point. It really did fluctuate from place to place.
Since your trip is first week in Sept 2018 it tends to be 10-15 degrees cooler on avg. that time of year.
So figure partly sunny mid 60's when you go. Some days will be warmer. Others cooler. Sometimes it may rain with a heavy or light wind. Other days could be beautiful skies. Or a combination of the two.
Which as
@JenTen1585 is advising - would not be shorts weather for most. You can always pack shorts if mid/high 60's = shorts for you. (It does for some here in NJ.)
Otherwise, plan to dress in layers and pack a few key articles to cover changes in weather. The temps typically started out cooler in the mornings and most excursions were FULL DAY.
We carried a waterproof windbreaker type jacket whenever we ventured out to cover surprise weather shifts.
Here's a great resource to track the historical temps.
https://www.timeanddate.com/weather/uk/oxford/historic?month=7&year=2017
You can select my month: July 2017 and compare it to Sept. 2017 for the dates that correlate to your trip next year.
It gives temps for am/mid day/pm with icons for weather changes from sunny to pt. cloudy to rain etc....
For example: (I'll post a few similar ports to some of the 2018 cruises)
Sat. July 8, 2017 = 77 was the high in Stonehenge / 78.8 high in Oxford / 77 high in Windsor
Sat. Sept 2, 2017= 68 was the high in Stonehenge / 69.8 high in Oxford / 72 high in Windsor
Many dressed like this in the am at Stonehenge on July 8: (low 70's)
and shed a layer or two by the afternoon in Windsor: (78 degree weather)
Same for Dover:
Sun July 9, 2017 = Dover - embarkation day = sunny high 78
Sat Sept 2, 2017 = Dover high 64
So the am starts out like this on July 8th: (mid 70's)
with similar clothing for 78 degree weather as we check-in at the port
But you're going to have low/mid 60's for the most part.
That would compare to our day in
Le Havre, France
Mon July 10. 2017 = 8:30am overcast wind light drizzle 63 degrees - in port
afternoon = pt sunny high 66 - Pointe du Hoc (Normandy)
Or our day in
Portland (JQ & I visited Glastonbury)
Tue July 11, 2017 Glastonbury = am overcast high 64/noon = rain temp dropped to 61. And VERY WINDY at the top of Glastonbury Tor
Tue Sept 5, 2017 Glastonbury = pt sunny high 73 (beautiful day for Sept)
so we start out dressed like this (JQ holding his red waterproof jacket) - low 60's
by noon a light steady rain picked up and the temps dropped to - 61 (hence the raingear)
I hope this proves helpful!
You can also check out the various outfits in the crowd when I post our visits to these ports as they may have similar weather to you as well.
Dublin, Ireland
Thurs July 13, 2017 = pt. sunny high 68
Liverpool, England
Fri July 14, 2017 = mostly sunny high 64
Greenock, Scotland (Edinburgh)
Sat Jul 15, 2017 = overcast/rain_am 64/noon 68