I am using the weather.nominal dataset and NaiveBayes classifier in Weka.
I have been able to build the classifier, but now I would like to classify new records. How can I use Weka to do that?
Can someone please tell me the procedure?
Once you have trained your model, you can then supply a testing set for evaluation.
To do this, click on the 'Set...' Button next to the Supplied Test Set Radio Button as shown below:

Once a Testing Set is entered, you could Right click on the model and select 'Re-evaluate model on current test set' as shown below:

Hope this Helps!