Surf Forecast for Riyue Bay
type: Dataset
description: 10-day surf forecast with Strike Scores for Riyue Bay, Wanning, China
about: Riyue Bay
  type: TouristAttraction
  geo: GeoCoordinates
    latitude: 18.62969
    longitude: 110.21488
  description: Riyue Bay is China's flagship surf destination—a consistent beach break on tropical Hainan Island that hosts WSL Championship Tour events. The Chinese government has invested heavily in surf infrastructure here, building world-class facilities and promoting the sport. Typhoon swells and NE monsoon winds create regular waves during autumn and winter. China's surf culture is exploding, and Riyue Bay is ground zero for the mainland's wave-riding revolution.
summary:
  best day:
    date: 2026-08-06
    score: 65
    category: Good
    explanation: Best day in the forecast: 2026-08-06 with a score of 65/100 (Good)
  firing days count: 0
  overall recommendation: Poor conditions overall: Average score 50/100. Look for spots with better forecasts.
forecasts:
  date: 2026-08-05
  day index: 0
  strike score:
    final score: 44
    category: Poor
    category emoji: 💤
    confidence: 1
    confidence explanation: Very high confidence (0-1 day forecast)
    breakdown:
      swell direction:
        score: 21
        out of: 25
        explanation: Good alignment: Swell from 118° is 8° off optimal 110°, still within prime range.
      swell size:
        score: 3
        out of: 25
        explanation: Too small: 0.5m is below minimum 0.6m. Waves will be weak/mushy.
      swell period:
        score: 15
        out of: 25
        explanation: Moderate period: 16s meets minimum 6s but below ideal 10s. Some groundswell energy present.
      wind:
        score: 11
        out of: 25
        explanation: Onshore/cross-shore: 11 km/h from 225° (SW). Destroying wave quality. Offshore range: 230°-310°.
    adjustments:
      wind history:
        adjustment: 0
        groomed: false
        morning sickness: false
        explanation: No significant wind history adjustment.
      windswell penalty:
        adjustment: 0
        windswell degraded: false
        explanation: Groundswell-dominant conditions (clean, long-period waves).
      secondary swell bonus:
        adjustment: 0
        explanation: No secondary swell bonus.
    summary: Poor conditions at Riyue Bay. Either swell direction (118°), size (0.5m), or wind (11 km/h from 225°) is unfavorable. Consider other spots or wait for better conditions.
  conditions:
    swell:
      height m: 0.5
      height ft: 1.6
      direction degrees: 118
      direction cardinal: ESE
      period s: 16
      explanation: 0.5m (1.6ft) swell from 118° (ESE) at 16s period
    wind:
      speed kmh: 11
      speed mph: 6.8
      direction degrees: 225
      direction cardinal: SW
      explanation: 11 km/h (7 mph) from 225° (SW)
forecasts:
  date: 2026-08-06
  day index: 1
  strike score:
    final score: 65
    category: Good
    category emoji: ✅
    confidence: 1
    confidence explanation: Very high confidence (0-1 day forecast)
    breakdown:
      swell direction:
        score: 8
        out of: 25
        explanation: Poor alignment: Swell from 159° is 49° off optimal 110°, barely within workable range 70°-150°.
      swell size:
        score: 9
        out of: 25
        explanation: Marginal size: 0.7m is 0.9m from ideal 1.6m.
      swell period:
        score: 25
        out of: 25
        explanation: Perfect period: 11s is at or above ideal 10s. Long-period groundswell with maximum power.
      wind:
        score: 21
        out of: 25
        explanation: Light offshore: 6 km/h from 243° (WSW). Grooming the wave face beautifully.
    adjustments:
      wind history:
        adjustment: 0
        groomed: false
        morning sickness: false
        explanation: No significant wind history adjustment.
      windswell penalty:
        adjustment: 0
        windswell degraded: false
        explanation: Groundswell-dominant conditions (clean, long-period waves).
      secondary swell bonus:
        adjustment: 0
        explanation: No secondary swell bonus.
    summary: Good surfable conditions at Riyue Bay. 0.7m swell from 159° with manageable wind. Solid session guaranteed.
  conditions:
    swell:
      height m: 0.7
      height ft: 2.3
      direction degrees: 159
      direction cardinal: SSE
      period s: 11
      explanation: 0.7m (2.3ft) swell from 159° (SSE) at 11s period
    wind:
      speed kmh: 6
      speed mph: 3.7
      direction degrees: 243
      direction cardinal: WSW
      explanation: 6 km/h (4 mph) from 243° (WSW)
forecasts:
  date: 2026-08-07
  day index: 2
  strike score:
    final score: 35
    category: Poor
    category emoji: 💤
    confidence: 0.95
    confidence explanation: High confidence (2-3 day forecast)
    breakdown:
      swell direction:
        score: 2
        out of: 25
        explanation: Poor alignment: Swell from 188° is 78° off optimal 110°, barely within workable range 70°-150°.
      swell size:
        score: 11
        out of: 25
        explanation: Marginal size: 1.0m is 0.6m from ideal 1.6m.
      swell period:
        score: 6
        out of: 25
        explanation: Moderate period: 7s meets minimum 6s but below ideal 10s. Some groundswell energy present.
      wind:
        score: 20
        out of: 25
        explanation: Light offshore: 7 km/h from 232° (SW). Grooming the wave face beautifully.
    adjustments:
      wind history:
        adjustment: 0
        groomed: false
        morning sickness: false
        explanation: No significant wind history adjustment.
      windswell penalty:
        adjustment: 0
        windswell degraded: false
        explanation: Groundswell-dominant conditions (clean, long-period waves).
      secondary swell bonus:
        adjustment: 0
        explanation: No secondary swell bonus.
    summary: Poor conditions at Riyue Bay. Either swell direction (188°), size (1.0m), or wind (7 km/h from 232°) is unfavorable. Consider other spots or wait for better conditions.
  conditions:
    swell:
      height m: 1
      height ft: 3.3
      direction degrees: 188
      direction cardinal: S
      period s: 7
      explanation: 1.0m (3.3ft) swell from 188° (S) at 7s period
    wind:
      speed kmh: 7
      speed mph: 4.3
      direction degrees: 232
      direction cardinal: SW
      explanation: 7 km/h (4 mph) from 232° (SW)
forecasts:
  date: 2026-08-08
  day index: 3
  strike score:
    final score: 53
    category: Fair
    category emoji: 😐
    confidence: 0.92
    confidence explanation: High confidence (2-3 day forecast)
    breakdown:
      swell direction:
        score: 5
        out of: 25
        explanation: Poor alignment: Swell from 180° is 70° off optimal 110°, barely within workable range 70°-150°.
      swell size:
        score: 11
        out of: 25
        explanation: Marginal size: 1.0m is 0.6m from ideal 1.6m.
      swell period:
        score: 10
        out of: 25
        explanation: Moderate period: 8s meets minimum 6s but below ideal 10s. Some groundswell energy present.
      wind:
        score: 25
        out of: 25
        explanation: Onshore/cross-shore: 4 km/h from 214° (SW). Destroying wave quality. Offshore range: 230°-310°.
    summary: Surfable but not special at Riyue Bay. The 1.0m swell from 180° is workable, but conditions aren't ideal. Fine if you're local, but not worth a dedicated trip.
provider: Strike Mission
date published: 2026-08-05T05:51:48.826Z
temporal coverage: 2026-08-05/2026-08-14
data sources: Open-Meteo Marine API (swell/wave data)
data sources: Open-Meteo Weather API (wind/weather data)

wind history:
  adjustment: 0
  groomed: false
  morning sickness: false
  explanation: No significant wind history adjustment.
windswell penalty:
  adjustment: 0
  windswell degraded: false
  explanation: Groundswell-dominant conditions (clean, long-period waves).
secondary swell bonus:
  adjustment: 0
  explanation: No secondary swell bonus.

swell:
  height m: 1
  height ft: 3.3
  direction degrees: 180
  direction cardinal: S
  period s: 8
  explanation: 1.0m (3.3ft) swell from 180° (S) at 8s period
wind:
  speed kmh: 4
  speed mph: 2.5
  direction degrees: 214
  direction cardinal: SW
  explanation: 4 km/h (2 mph) from 214° (SW)

date: 2026-08-09
day index: 4
strike score:
  final score: 51
  category: Fair
  category emoji: 😐
  confidence: 0.89
  confidence explanation: Moderate confidence (4-5 day forecast)
  breakdown:
    swell direction:
      score: 3
      out of: 25
      explanation: Poor alignment: Swell from 187° is 77° off optimal 110°, barely within workable range 70°-150°.
    swell size:
      score: 11
      out of: 25
      explanation: Marginal size: 1.0m is 0.6m from ideal 1.6m.
    swell period:
      score: 21
      out of: 25
      explanation: Good period: 9s is 90% of ideal 10s. Clean, powerful groundswell.
    wind:
      score: 21
      out of: 25
      explanation: Onshore/cross-shore: 6 km/h from 227° (SW). Destroying wave quality. Offshore range: 230°-310°.
  adjustments:
    wind history:
      adjustment: 0
      groomed: false
      morning sickness: false
      explanation: No significant wind history adjustment.
    windswell penalty:
      adjustment: 0
      windswell degraded: false
      explanation: Groundswell-dominant conditions (clean, long-period waves).
    secondary swell bonus:
      adjustment: 0
      explanation: No secondary swell bonus.
  summary: Surfable but not special at Riyue Bay. The 1.0m swell from 187° is workable, but conditions aren't ideal. Fine if you're local, but not worth a dedicated trip.
conditions:
  swell:
    height m: 1
    height ft: 3.3
    direction degrees: 187
    direction cardinal: S
    period s: 9
    explanation: 1.0m (3.3ft) swell from 187° (S) at 9s period
  wind:
    speed kmh: 6
    speed mph: 3.7
    direction degrees: 227
    direction cardinal: SW
    explanation: 6 km/h (4 mph) from 227° (SW)

date: 2026-08-10
day index: 5
strike score:
  final score: 55
  category: Fair
  category emoji: 😐
  confidence: 0.86
  confidence explanation: Moderate confidence (4-5 day forecast)
  breakdown:
    swell direction:
      score: 5
      out of: 25
      explanation: Poor alignment: Swell from 178° is 68° off optimal 110°, barely within workable range 70°-150°.
    swell size:
      score: 12
      out of: 25
      explanation: Marginal size: 1.1m is 0.4m from ideal 1.6m.
    swell period:
      score: 21
      out of: 25
      explanation: Good period: 9s is 90% of ideal 10s. Clean, powerful groundswell.
    wind:
      score: 21
      out of: 25
      explanation: Onshore/cross-shore: 6 km/h from 221° (SW). Destroying wave quality. Offshore range: 230°-310°.
  adjustments:
    wind history:
      adjustment: 0
      groomed: false
      morning sickness: false
      explanation: No significant wind history adjustment.
    windswell penalty:
      adjustment: 0
      windswell degraded: false
      explanation: Groundswell-dominant conditions (clean, long-period waves).
    secondary swell bonus:
      adjustment: 0
      explanation: No secondary swell bonus.
  summary: Surfable but not special at Riyue Bay. The 1.1m swell from 178° is workable, but conditions aren't ideal. Fine if you're local, but not worth a dedicated trip.
conditions:
  swell:
    height m: 1.1
    height ft: 3.6
    direction degrees: 178
    direction cardinal: S
    period s: 9
    explanation: 1.1m (3.6ft) swell from 178° (S) at 9s period
  wind:
    speed kmh: 6
    speed mph: 3.7
    direction degrees: 221
    direction cardinal: SW
    explanation: 6 km/h (4 mph) from 221° (SW)

date: 2026-08-11
day index: 6
strike score:
  final score: 50
  category: Fair
  category emoji: 😐
  confidence: 0.83
  confidence explanation: Low confidence (6-7 day forecast)
  breakdown:
    swell direction:
      score: 4
      out of: 25
      explanation: Poor alignment: Swell from 183° is 73° off optimal 110°, barely within workable range 70°-150°.
    swell size:
      score: 13
      out of: 25
      explanation: Marginal size: 1.2m is 0.4m from ideal 1.6m.
    swell period:
      score: 21
      out of: 25
      explanation: Good period: 9s is 90% of ideal 10s. Clean, powerful groundswell.
    wind:
      score: 16
      out of: 25
      explanation: Light offshore: 9 km/h from 250° (WSW). Grooming the wave face beautifully.
  adjustments:
    wind history:
      adjustment: 0
      groomed: false
      morning sickness: false
      explanation: No significant wind history adjustment.
    windswell penalty:
      adjustment: 0
      windswell degraded: false
      explanation: Groundswell-dominant conditions (clean, long-period waves).
    secondary swell bonus:
      adjustment: 0
      explanation: No secondary swell bonus.
  summary: Surfable but not special at Riyue Bay. The 1.2m swell from 183° is workable, but conditions aren't ideal. Fine if you're local, but not worth a dedicated trip.
conditions:
  swell:
    height m: 1.2
    height ft: 3.9
    direction degrees: 183
    direction cardinal: S
    period s: 9
    explanation: 1.2m (3.9ft) swell from 183° (S) at 9s period
  wind:
    speed kmh: 9
    speed mph: 5.6
    direction degrees: 250
    direction cardinal: WSW
    explanation: 9 km/h (6 mph) from 250° (WSW)

date: 2026-08-12
day index: 7
strike score:
  final score: 52
  category: Fair
  category emoji: 😐
  confidence: 0.8
  confidence explanation: Low confidence (6-7 day forecast)
  breakdown:
    swell direction:
      score: 7
      out of: 25
      explanation: Poor alignment: Swell from 165° is 55° off optimal 110°, barely within workable range 70°-150°.
    swell size:
      score: 13
      out of: 25
      explanation: Marginal size: 1.2m is 0.4m from ideal 1.6m.
    swell period:
      score: 25
      out of: 25
      explanation: Perfect period: 10s is at or above ideal 10s. Long-period groundswell with maximum power.
    wind:
      score: 11
      out of: 25
      explanation: Onshore/cross-shore: 11 km/h from 229° (SW). Destroying wave quality. Offshore range: 230°-310°.
  adjustments:
    wind history:
      adjustment: 0
      groomed: false
      morning sickness: false
      explanation: No significant wind history adjustment.
    windswell penalty:
      adjustment: 0
      windswell degraded: false
      explanation: Groundswell-dominant conditions (clean, long-period waves).
    secondary swell bonus:
      adjustment: 0
      explanation: No secondary swell bonus.
  summary: Surfable but not special at Riyue Bay. The 1.2m swell from 165° is workable, but conditions aren't ideal. Fine if you're local, but not worth a dedicated trip.
conditions:
  swell:
    height m: 1.2
    height ft: 3.9
    direction degrees: 165
    direction cardinal: SSE
    period s: 10
    explanation: 1.2m (3.9ft) swell from 165° (SSE) at 10s period
  wind:
    speed kmh: 11
    speed mph: 6.8
    direction degrees: 229
    direction cardinal: SW
    explanation: 11 km/h (7 mph) from 229° (SW)
  windswell:
    height m: 0.4
    period s: 2
    explanation: Local wind-generated waves (choppy, short-period)

date: 2026-08-13
day index: 8
strike score:
  final score: 46
  category: Fair
  category emoji: 😐
  confidence: 0.8
  confidence explanation: Very low confidence (8-10 day forecast, conditions may change)
  breakdown:
    swell direction:
      score: 6
      out of: 25
      explanation: Poor alignment: Swell from 177° is 67° off optimal 110°, barely within workable range 70°-150°.
    swell size:
      score: 10
      out of: 25
      explanation: Marginal size: 0.8m is 0.8m from ideal 1.6m.
    swell period:
      score: 25
      out of: 25
      explanation: Perfect period: 10s is at or above ideal 10s. Long-period groundswell with maximum power.
    wind:
      score: 9
      out of: 25
      explanation: Moderate offshore: 12 km/h from 230° (SW). Still grooming but noticeable wind.
  adjustments:
    wind history:
      adjustment: 0
      groomed: false
      morning sickness: false
      explanation: No significant wind history adjustment.
    windswell penalty:
      adjustment: 0
      windswell degraded: false
      explanation: Groundswell-dominant conditions (clean, long-period waves).
    secondary swell bonus:
      adjustment: 0
      explanation: No secondary swell bonus.
  summary: Surfable but not special at Riyue Bay. The 0.8m swell from 177° is workable, but conditions aren't ideal. Fine if you're local, but not worth a dedicated trip.
conditions:
  swell:
    height m: 0.8
    height ft: 2.6
    direction degrees: 177
    direction cardinal: S
    period s: 10
    explanation: 0.8m (2.6ft) swell from 177° (S) at 10s period
  wind:
    speed kmh: 12
    speed mph: 7.5
    direction degrees: 230
    direction cardinal: SW
    explanation: 12 km/h (7 mph) from 230° (SW)
  windswell:
    height m: 0.3
    period s: 2
    explanation: Local wind-generated waves (choppy, short-period)

date: 2026-08-14
day index: 9
strike score:
  final score: 44
  category: Poor
  category emoji: 💤
  confidence: 0.8
  confidence explanation: Very low confidence (8-10 day forecast, conditions may change)
  breakdown:
    swell direction:
      score: 7
      out of: 25
      explanation: Poor alignment: Swell from 166° is 56° off optimal 110°, barely within workable range 70°-150°.
    swell size:
      score: 9
      out of: 25
      explanation: Marginal size: 0.7m is 0.9m from ideal 1.6m.
    swell period:
      score: 25
      out of: 25
      explanation: Perfect period: 10s is at or above ideal 10s. Long-period groundswell with maximum power.
    wind:
      score: 16
      out of: 25
      explanation: Onshore/cross-shore: 9 km/h from 228° (SW). Destroying wave quality. Offshore range: 230°-310°.
  adjustments:
    wind history:
      adjustment: 0
      groomed: false
      morning sickness: false
      explanation: No significant wind history adjustment.
    windswell penalty:
      adjustment: 0
      windswell degraded: false
      explanation: Groundswell-dominant conditions (clean, long-period waves).
    secondary swell bonus:
      adjustment: 0
      explanation: No secondary swell bonus.
  summary: Poor conditions at Riyue Bay. Either swell direction (166°), size (0.7m), or wind (9 km/h from 228°) is unfavorable. Consider other spots or wait for better conditions.
conditions:
  swell:
    height m: 0.7
    height ft: 2.3
    direction degrees: 166
    direction cardinal: SSE
    period s: 10
    explanation: 0.7m (2.3ft) swell from 166° (SSE) at 10s period
  wind:
    speed kmh: 9
    speed mph: 5.6
    direction degrees: 228
    direction cardinal: SW
    explanation: 9 km/h (6 mph) from 228° (SW)

Strike Mission
type: Organization