Here is a summary of the September weather:
Summary for period 01/09/2013 to 30/09/2013
Mean (1 minute) 14.2
Mean (min+max) 15.2
Mean Minimum 9.4
Mean Maximum 21.0
Minimum 4.8 on 09/09/2013
Maximum 30.8 on 04/09/2013
Highest Minimum 13.2 on 03/09/2013
Lowest Maximum 12.1 on 17/09/2013
Air frosts 0
Total for period 1.00
Wettest day 0.18 on 13/09/2013
High rain rate 0.72 day 06/09/2013
Rain days 15
Dry days 15
Highest Gust 22 on 15/09/2013
Average Speed 1
Wind Run 869.3 miles
Gale days 0
Maximum 1030.8 on 01/09/2013
Minimum 995.4 on 17/09/2013
and a graph of the outside temperature:
As you can see the month started out pretty warm, went through a colder period in the middle, then warmed up again. I think the average for the month was higher than the normal for September.
The rain only happened on a few days, but when it did rain it rained quite a lot in a short while.
Not very windy overall.
Not a bad month for the garden, though a bit more rain would have been preferable.