Amsterdam -weather. What type of clothing?

It can be anything between chilly (but not cold) to warm (but not hot). A light rain jacket and a light sweater in combination with (t-)shirts should do the trick.

I was there early May 2014. Highs were in the 50s. We had one night that went down to the low 30s while in Haarlem and we were on a barge so not the best heating in the world! That was a cold snap but if you have room I'd suggest throwing in a pair of lightweight gloves and toboggan (knit hat) because you never know! A fleece or sweater and rain-type jacket or wind shell would be smart. Watch the weather a few days before you leave to see what's trending.

Agree with Rachel. I spent a few weeks there in May and found other than as a layer underneath a sweater, I really did not need anything with short sleeves as it was often damp, windy and chilly. I had a suede jacket, a packable rain jacket w/ hood, a lightweight fleece pullover, a sweater and several long sleeve tees. My infinity scarf, a knit hat and pair of fleece gloves also got worn often when I was out and about. I also had a small travel umbrella that was put to use many times (you can buy one over there, but if you check the weather reports right before your departure and see a lot of rain in the forecast, best to just try and fit one in your luggage).

On Mother's day in 2005 we just about died of heat ( in the 90-s ) and had to buy some cheap T-shirts to be comfortable. Turns out that the whole summer of 2005 was cold and wet that year so I guess we were kind of lucky.
In 1994 at the end of April we had wet snow and sleet. Had to seek shelter in the warm "orchid " house at Keukenhof .
You never know in the Netherlands so ; layers , layers and a waterproof windbreaker . I like poncho's myself , keeps bag/backpack also dry.

Weather stats for Amsterdam:
http://www.yr.no/place/Netherlands/North_Holland/Amsterdam/statistics.html

Keeping in mind that average weather is average, average minimum daily of 6C and average maximum daily of 15C with precipitation 9 days of a month. For my metabolism, that is comfortable cool mid days to cool (sweater or light fleece weather) evenings and expecting to need a wind/rain jacket.

The problem I had in Amsterdam in April is that it is a maritime climate, which is another way of saying it's always extremely damp. So, when it was 50 degrees, it felt much colder. However, if I wore a cashmere sweater, I was much too hot. I had only brought one cotton sweater - and ended up wearing it every single day for 10 days, since my other sweater was too hot, and without the sweater I was FREEZING.

So, plan on lots of layers, but no single layer should be too warm, or you'll roast.

Weather can change in a few minutes-- I wear a very light rain layer on top of a thin sweater and a t-shirt/light shirt. I've been there at various times of year and my clothing choice makes a difference. Even carrying a small umbrella at all times is wise.

Cleo

The latest forecast is a stiff 10 C, with a little sun, but dry.