Re: adjective+ uncountable nouns
I agree with the others about #1 - use "the freezing sleet" if it has already been mentioned earlier in the conversation/piece.
Originally Posted by Bassim
#2 is OK with the indefinite article. It works the same way as "A cold wind was blowing ..."
#3 is OK with the indefinite article but it's also possible to use no article or the definite article.
Freezing sleet hit my face as I walked.
The freezing sleet which was hitting my face as I walked was making my cheeks numb.
Remember - correct capitalisation, punctuation and spacing make posts much easier to read.