Two colloquial phrases from Costa Rica I recently learned from spanishpod101 are related to this:
Son pelitos de gato nada mas
Translates to: "It's just little cat hairs". Meaning it's only light rain/drizzle
San Pedro esta corriendo los muebles
Translates to "St Peter is moving the furniture around". Meaning there is a big storm.
Here is the link to the podcast:
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