The Northface shell sounds perfect to me. My son uses them all the time - they are work issued in his case for when he is "doing" football or other OB's but he wears them outside work too.
Long range forecast is 23rd 11 celsius, dropping to 8 on the Monday, minimums of 3-4 which will mean a ground frost and showery. Of course it could all change again by then, but I think you are good to go with what you have.
Have a great trip to Nairobi and enjoy Amsterdam!