Will it be sunny?
Weather
The climate of Budapest is "humid continental" with warm or very warm summers. Winter (November until early March) can be cold and there is little sunshine. Snowfall is fairly frequent in most years, and nighttime temperatures of −15 °C (5 °F) are not uncommon from mid-December until mid-February. The spring months (March and April) see variable conditions, with a rapid increase in the average temperature. The weather in late March and April is often very agreeable during the day and fresh at night. Budapest's long summer - lasting from May until mid-September - is warm or very warm. Budapest has as much summer sunshine as many Mediterranean resorts. Sudden heavy showers also occur, particularly in May and June. The autumn in Budapest (mid-September until late October) is characterized by little rain and long sunny days with moderate temperatures. Read more on Wikipedia

Weather forecast for Budapest:
http://www.intellicast.com/Local/Weather.aspx?location=HUXX0002

Historical weather averages for Budapest:
http://www.intellicast.com/Local/History.aspx?location=HUXX0002