When used at the end of a statement, "啊" can also express an exclamation, e.g., "今天天气真凉快啊!" (Today's weather is really cool!), "这张照片真漂亮啊!" (How beautiful the picture looks!)
The punctuation mark is usually an exclamation point "!", which is the same in Cantonese.
"了" indicates the change of states. It means that the weather has changed and has been cooler now.
"piào 票" (ticket) means ticket or fare in English. If you want to state what kind of ticket it is, you can precede the word "票" with other nouns. For example,