The weather changes in Helsinki are pretty abrupt and I have never seen such changes before. This weekend was fantastic with the temperature being in positives and Monday morning suddenly is -14 degrees! Crazy. The above graph is from http://www.ilmatieteenlaitos.fi/weather/local.html?kunta=Espoo and it shows the temperature over the past 24 hours. Notice that in the last 12 hours, the temperature dropped about 15 degrees.
Now, Who needs weather forecasts the most? Here is my list in the order of importance
a) airline companies: to calculate the fuel they need for a trip, the visibility conditions at the airport and stuff like that.
b) energy companies: to predict the short-term demand for energy. The Helsinki energy company, for example, could really use this information to predict how much of heating needs would increase in the next day and keep their supply up to date.
c) you and i: to decide what clothes to wear the next day; to carry an umbrella or not or to take a vacation in someplace or not.
Of the above, option (c) would pay nothing to learn of weather forecasts, but apparently the first two of the lot would happily part with lots of money to get more accurate information.