"surf's up" meaning in English

{
  "etymology_text": "Originally used in surfing to say there are good waves for surfing and one should get ready to ride them. This likely resulted in the later idiomatic use: to get ready for something.",
  "head_templates": [
    {
      "args": {
        "1": "en",
        "2": "phrase",
        "head": "surf's up"
      },
      "expansion": "surf's up",
      "name": "head"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "phrase",
  "senses": [
    {
      "categories": [
        {
          "_dis": "100 0",
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w+disamb"
        },
        {
          "_dis": "100 0",
          "kind": "other",
          "name": "English entries with topic categories using raw markup",
          "parents": [
            "Entries with topic categories using raw markup",
            "Entry maintenance"
          ],
          "source": "w+disamb"
        },
        {
          "_dis": "100 0",
          "kind": "other",
          "name": "English terms with non-redundant non-automated sortkeys",
          "parents": [
            "Terms with non-redundant non-automated sortkeys",
            "Entry maintenance"
          ],
          "source": "w+disamb"
        },
        {
          "_dis": "100 0",
          "kind": "topical",
          "langcode": "en",
          "name": "Surfing",
          "orig": "en:Surfing",
          "parents": [
            "Water sports",
            "Sports",
            "Human activity",
            "Human behaviour",
            "Human",
            "All topics",
            "Fundamental"
          ],
          "source": "w+disamb"
        }
      ],
      "glosses": [
        "A phrase used in surfing when a nearby wave is passing."
      ],
      "id": "en-surf's_up-en-phrase-PcLxUHoW"
    },
    {
      "categories": [],
      "examples": [
        {
          "text": "Yo, Harold! Surf's up! Those cars aren't going to wash themselves!"
        }
      ],
      "glosses": [
        "It's time (to do something)."
      ],
      "id": "en-surf's_up-en-phrase-wgb7Ht9O",
      "raw_glosses": [
        "(idiomatic) It's time (to do something)."
      ],
      "tags": [
        "idiomatic"
      ]
    }
  ],
  "sounds": [
    {
      "audio": "En-au-surf's up.ogg",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/a/a5/En-au-surf%27s_up.ogg/En-au-surf%27s_up.ogg.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/a/a5/En-au-surf%27s_up.ogg",
      "tags": [
        "Australia"
      ],
      "text": "Audio (AU)"
    }
  ],
  "word": "surf's up"
}

{
  "categories": [
    "English entries with incorrect language header",
    "English entries with topic categories using raw markup",
    "English lemmas",
    "English multiword terms",
    "English phrases",
    "English terms with audio links",
    "English terms with non-redundant non-automated sortkeys",
    "en:Surfing"
  ],
  "etymology_text": "Originally used in surfing to say there are good waves for surfing and one should get ready to ride them. This likely resulted in the later idiomatic use: to get ready for something.",
  "head_templates": [
    {
      "args": {
        "1": "en",
        "2": "phrase",
        "head": "surf's up"
      },
      "expansion": "surf's up",
      "name": "head"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "phrase",
  "senses": [
    {
      "glosses": [
        "A phrase used in surfing when a nearby wave is passing."
      ]
    },
    {
      "categories": [
        "English idioms"
      ],
      "examples": [
        {
          "text": "Yo, Harold! Surf's up! Those cars aren't going to wash themselves!"
        }
      ],
      "glosses": [
        "It's time (to do something)."
      ],
      "raw_glosses": [
        "(idiomatic) It's time (to do something)."
      ],
      "tags": [
        "idiomatic"
      ]
    }
  ],
  "sounds": [
    {
      "audio": "En-au-surf's up.ogg",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/a/a5/En-au-surf%27s_up.ogg/En-au-surf%27s_up.ogg.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/a/a5/En-au-surf%27s_up.ogg",
      "tags": [
        "Australia"
      ],
      "text": "Audio (AU)"
    }
  ],
  "word": "surf's up"
}