PILOT CHARTS FOR THE DANGEROUS MIDDLE
OVERVIEW OF THE DANGEROUS MIDDLE
The Dangerous Middle
in the South Pacific, between French Polynesia and Tonga/Fiji, is a notorious stretch of ocean that presents several key challenges for sailors. Unlike the well-established tradewind routes, this area can be unpredictable due to unstable weather systems, large swells, and the risk of encountering Pacific lows. Hereโs what makes it tricky:
1. Weather Systems & Pacific Lows
- Unstable Trade Winds: The steady SE trades that dominate further east can become unreliable in this zone, with patches of dead calm or sudden shifts.
- Frequent Pacific Lows: Mid-latitude lows can push up into this area, disrupting the trades and bringing strong winds, squalls, and heavy rain. Some develop into full-blown storms.
THESE LOWS FORM IN THE TASMAN SEA AND BLOW ACROSS TO CHILE EVERY 6-7 DAYS FROM WEST TO EAST - Convergence Zones: The South Pacific Convergence Zone (SPCZ) often lurks here, producing unpredictable weather, cloud cover, squalls, and rain. It can shift north or south, making it hard to predict conditions.
2. Swells & Sea State
- Southern Ocean Swells: Large, long-period swells generated by deep Southern Ocean storms can roll up into this area, sometimes conflicting with the wind waves from the trades. This can create a confused sea state, making for rough and uncomfortable sailing.
- Cross Swell Issues: Swells from the Southern Ocean often mix with wind-driven waves from the trades or storms, leading to a choppy, chaotic sea state thatโs hard to predict.
3. Passage Strategy & Route Planning
- Timing is Critical: The best time to cross is during the Southern Hemisphere winter (MayโOctober) when the trades are more settled and fewer lows track northward.
- Weather Routing is Essential: Given the unpredictable systems, watching GRIB files isnโt enoughโhaving real-time weather updates or a router can be a lifesaver.
- Go North or South?: Many sailors try to route either north (closer to the equator) or south (closer to 20ยฐS) to avoid the worst of the SPCZ and low-pressure disturbances.
4. Landfall Risks & Cyclone Considerations
- Tonga & Fiji Entry: Weather windows into these areas can be tricky, as squalls and strong winds often funnel through gaps in the island chains.
- Cyclones (Out of Season, But Still a Risk): The South Pacific has had late and early-season cyclones in recent years, so even outside the official season, you need to watch long-range forecasts.
ย
Final Thoughts
Many sailors are challenged by this leg of a Pacific crossing but wuth timing, itโs manageable. Some choose to break it up with stops in places like Suwarrow (Cook Islands) or Niue, but those require good weather windows for entry and exit.
Weather Patterns
WINDS
Tides and Currents
SWELL AND WAVESย
2024
2023
2022
https://forecast.predictwind.com/tracking/rally/pacific-posse23/ย