(1) Explain your problem, don't simply post "This isn't working". What were you doing when you faced the problem? What have you tried to resolve - did you look for a solution using "Search" ? Has it happened just once or several times?
(2) It's also good to get feedback when a solution is found, return to the original post to explain how it was resolved so that more people can also use the results.
How would you show potential risk incurred by poor weather condition in the schedule?
Would you prefering a single contingency activity at the end of the schedule stating it's used to account for all potential risks?