[{"data":1,"prerenderedAt":210},["ShallowReactive",2],{"leaderboard-total":3,"spot-seo-castle-rock":9,"spot-castle-rock":51},{"entries":4,"total":5,"period":6,"type":7,"generated_at":8},[],0,"all_time","reports","2026-10-03T06:32:05.526386Z",{"title":10,"description":11,"canonical_url":12,"og_image":13,"structured_data":14,"breadcrumbs":44},"Snorkeling Conditions at Castle Rock - How's the Spot","Check snorkeling conditions at Castle Rock, Victoria. Fair conditions, water 14.6°C, waves 0.16m","https:\u002F\u002Fhowsthespot.com\u002Fspots\u002Fcastle-rock","https:\u002F\u002Fhowsthespot.syd1.cdn.digitaloceanspaces.com\u002Fspots\u002Fimport_castle-rock_0_f511028ba554.jpg",[15,28],{"@context":16,"@type":17,"name":18,"description":19,"url":12,"geo":20,"address":24},"https:\u002F\u002Fschema.org","Place","Castle Rock","Castle Rock is a prominent underwater reef bommie (pinnacle) located just outside the heads of Port Phillip Bay near the Mornington Peninsula. Rising from the seabed to around 12–20 metres depth, t...",{"@type":21,"latitude":22,"longitude":23},"GeoCoordinates",-38.22882,145.060045,{"@type":25,"addressRegion":26,"addressCountry":27},"PostalAddress","Victoria","Australia",{"@context":16,"@type":29,"name":30,"description":11,"url":12,"breadcrumb":31},"WebPage","Snorkeling Conditions at Castle Rock",{"@context":16,"@type":32,"itemListElement":33},"BreadcrumbList",[34,39,42],{"@type":35,"position":36,"name":37,"item":38},"ListItem",1,"Home","https:\u002F\u002Fhowsthespot.com",{"@type":35,"position":40,"name":26,"item":41},2,"https:\u002F\u002Fhowsthespot.com\u002Fexplore?region=victoria",{"@type":35,"position":43,"name":18,"item":12},3,[45,47,49],{"label":37,"href":46},"\u002F",{"label":26,"href":48},"\u002Fexplore?region=victoria",{"label":18,"href":50},"\u002Fspots\u002Fcastle-rock",{"id":52,"name":18,"slug":53,"latitude":22,"longitude":23,"description":54,"difficulty":55,"image_url":13,"status":56,"tide_constituents":57,"hazard_entries":108,"access_info_structured":144,"area_boundary":118,"routes":118,"created_at":152,"updated_at":153,"today_conditions":154,"today_verdict_view":175,"images":199,"submitted_by":207,"region_name":26,"verification_status":209,"verified_at":118,"disputed":160,"verifier_count":5,"last_verified_display_name":118},"bd82e719-7365-4538-afc8-f4b32e6cd692","castle-rock","Castle Rock is a prominent underwater reef bommie (pinnacle) located just outside the heads of Port Phillip Bay near the Mornington Peninsula. Rising from the seabed to around 12–20 metres depth, this rocky submarine feature is cloaked in colourful temperate kelp forests and encrusting sponges, frequented by Weedy Sea Dragons, schools of Bullseyes, and Eastern Blue Groper. The site is a firm favourite among divers and advanced snorkellers for its dramatic topography and rich Great Southern Reef biodiversity. Often accessed by boat from Queenscliff or Portsea, Castle Rock offers excellent visibility when conditions align, with the surrounding currents supporting a thriving ecosystem of reef fish, crayfish, and nudibranchs.","advanced","published",{"name":58,"amplitude":74,"phase":90,"latitude":22,"model":106,"epoch":107},[59,60,61,62,63,64,65,66,67,68,69,70,71,72,73],"2N2","J1","K1","K2","M2","M4","MF","MM","N2","O1","P1","Q1","S1","S2","T2",[75,76,77,78,79,80,81,82,83,84,85,86,87,88,89],0.009584982480253773,0.008455112289219106,0.1525431574719473,0.006197386866469564,0.2725011450242494,0.006417059722901437,0.008552161129250356,0.000505806328973947,0.028440500326548847,0.06941761033656182,0.03201070739335061,0.03089887491598992,0.014962451310121526,0.10290492570186924,0.019445741901147007,[91,92,93,94,95,96,97,98,99,100,101,102,103,104,105],44.38985562049182,315.7774696935229,294.0996178898242,31.149352782593436,26.56952116187844,239.75805709495455,152.66236852369502,186.7009657145664,30.938912546465904,288.94095184436145,289.51002370336386,280.08540723926586,16.167096090051647,225.8702402117749,196.8948193259505,"EOT20","1992-01-01T00:00:00Z",[109,115,119,123,126,129,133,136,141],{"name":110,"description":111,"severity":112,"season_start":113,"season_end":114},"Strong south-westerly swells","Exposed to powerful swells from the Southern Ocean via Bass Strait, which can create dangerous surf conditions suddenly.","warning",6,8,{"name":116,"description":117,"severity":112,"season_start":118,"season_end":118},"Strong currents and undertows","Tidal currents and undertows can be strong when snorkeling near the rock platforms, especially during outgoing tides.",null,{"name":120,"description":121,"severity":122,"season_start":118,"season_end":118},"Sudden weather changes","Weather conditions can shift rapidly along this exposed coastline, with increased wind and wave height developing quickly.","caution",{"name":124,"description":125,"severity":122,"season_start":118,"season_end":118},"Slippery rock platforms","Intertidal sandstone rock platforms are often wet and covered with algae, creating very slippery walking conditions.",{"name":127,"description":128,"severity":112,"season_start":118,"season_end":118},"Large unexpected waves","Sneaker waves can wash over rock platforms without warning, posing a risk to snorkelers and rockpoolers near the water's edge.",{"name":130,"description":131,"severity":112,"season_start":36,"season_end":132},"Strong tidal currents at Port Phillip Heads","Sweeping currents around the heads can be powerful, especially on outgoing tides, requiring good fitness and awareness.",12,{"name":134,"description":135,"severity":112,"season_start":36,"season_end":132},"Boat traffic","Located in a shipping channel approach with regular vessel traffic; snorkellers must stay vigilant and use a surface marker buoy.",{"name":137,"description":138,"severity":122,"season_start":139,"season_end":140},"Cold water temperatures","Temperate waters range from 10–18°C year-round, posing a risk of hypothermia without proper exposure protection.",5,10,{"name":142,"description":143,"severity":122,"season_start":36,"season_end":132},"Variable visibility","Visibility can change rapidly from excellent (15m+) to poor (2-3m) due to swell and tide shifts.",{"directions":145,"parking":146,"facilities":147,"fees":150,"access_method":151},"Castle Rock is located outside the Port Phillip Heads near the Mornington Peninsula. It is typically accessed by private or charter boat launching from Queenscliff (about 15 min run) or Portsea. GPS marks are available from local dive shops. No shore access is possible — this is an offshore pinnacle.","Parking available at Queenscloff or Portsea boat ramps and nearby streets.",[148,149],"parking","boat_ramp","No entry fee; charter boat fees apply if hiring a service (approx. $80–$150 per person).","boat","2026-07-27T02:58:14.660523Z","2026-08-04T05:36:16.070440Z",{"verdict":155,"evaluated_at":156,"models":157},"marginal","2026-10-03T02:19:18.458133Z",[158,164,170],{"model_name":159,"is_favourable":160,"value":161,"threshold":140,"unit":162,"operator":163},"Wind Speed",false,10.06,"kn","lte",{"model_name":165,"is_favourable":166,"value":167,"threshold":168,"unit":169,"operator":163},"Wave Height",true,0.16,0.5,"m",{"model_name":171,"is_favourable":160,"value":172,"threshold":40,"unit":173,"operator":174},"Visibility",0.99,"","gte",{"verdict":155,"rating":176,"evaluated_at":156,"generated_at":156,"source":177,"confidence":178,"visibility":181,"parameters":182,"models_passed":36,"models_total":139},"Fair","precomputed",{"level":179,"value":180},"High",100,{"score":172,"rating":118,"confidence":118},[183,184,188,191,196],{"name":165,"value":167,"label":118,"unit":169,"favourable":166,"score":43,"optimal_max":168,"marginal_max":36},{"name":185,"value":186,"label":118,"unit":187,"favourable":160,"score":36,"optimal_max":114,"marginal_max":132},"Swell Period",10.75,"s",{"name":159,"value":189,"label":118,"unit":162,"favourable":160,"score":36,"optimal_max":140,"marginal_max":190},10.059372,15,{"name":192,"value":193,"label":118,"unit":194,"favourable":160,"score":5,"optimal_max":139,"marginal_max":195},"Precipitation",38.8,"mm",20,{"name":197,"value":118,"label":198,"unit":173,"favourable":160,"score":36,"optimal_max":118,"marginal_max":118},"Tidal Phase","flood",[200],{"id":201,"image_url":13,"sort_order":5,"is_primary":166,"moderation_status":202,"license":203,"license_url":204,"attribution":205,"author_name":206},"fa4e411f-7de7-42d8-a55e-7f9f30c0de8a","approved","CC BY-SA 4.0","https:\u002F\u002Fcreativecommons.org\u002Flicenses\u002Fby-sa\u002F4.0\u002F","Photo by Matthew C. Herne, Jay P. Nair, Alistair R. Evans and Alan M. Tait","Matthew C. Herne, Jay P. Nair, Alistair R. Evans and Alan M. Tait",{"display_name":208},"Daniel","unverified",1791009139398]