  Data mining is a popular concept of mined necessary data from a large set of
data. Data mining using clustering is a powerful way to analyze data and gives
prediction. In this paper non structural time series data is used to forecast
daily average temperature, humidity and overall weather conditions of Kolkata
city. The air pollution data have been taken from West Bengal Pollution Control
Board to build the original dataset on which the prediction approach of this
paper is studied and applied. This paper describes a new technique to predict
the weather conditions using convex hull which gives structural data and then
apply incremental K-means to define the appropriate clusters. It splits the
total database into four separate databases with respect to different weather
conditions. In the final step, the result will be calculated on the basis of
priority based protocol which is defined based on some mathematical deduction.
