The month of march look like it will be a very boring, gloomy month. Luckily there are many nice things to do in Stockholm anyway, FIKA is one of the best. Explore all the wonderful fika spots all over town, many with organic, homemade bread and buns!
Swedish shops are great, especially around SoFo area, a whole day spent shopping and fika is a great day.
The cultural house at T-centralen is another great place to go, usually there are exhibitions of different arts.