This is the 165th most frequent German word.
gute
"Good."
Here, 'gute' is used as an adjective modifying 'Reise' (a feminist singular noun in the accusative case), hence it adopts the appropriate gender and case endings.
Ich wünsche dir eine gute Reise.
I wish you a good journey.
In this instance, 'gute' is used as an attributive adjective describing 'Wetter' (a neuter singular noun in the nominative case), and it carries the default ending for neuter nominative singular.
Das gute Wetter hat allen gefallen.
The good weather pleased everyone.
Here, 'gute' is an adjective modifying 'Nachrichten' (a feminine plural noun), and it takes the plural declension ending for adjectives in the accusative case.