Monday, July 2, 2012

Day 9- South Pacific weather reality check

Time: 2200 Zulu (noon Hawaii time)
Position: 10-deg 16-min S 161-deg 47-min W
Wind: NE8 Seas: NE 6-ft, WSW 9-ft
Avg. Course: 194-deg T
Avg. Speed: 2.3-knots
Rig: 80% and full mains'l
24-hr distance made good: 54.2-nm
Distance to Suvarrov: 193-nm

Located 250-nm from Suvarrov, we were bobbing in light conditions and observing lots of convection with periods of moderate winds associated with squalls interspersed with no winds at all between them. Our most recent weather data showed that we should be safe 120-nm from the stationary front just north of Suvarrov. We were in no hurry to rush S and get closer to the disturbance and its Tstorms. However, Chris decided to run Yannie for a bit for several reasons (1) it is good for her to be run frequently and it had been over a week (2) our battery monitor was showing low and (3) to DO something besides flopping around waiting for wind. The good news, besides the fact that Yannie started right up, is that our batteries were actually mostly topped off already (which means just the monitor is mis-adjusted). The bad news is that we ended up losing the few miles we gained with the motor. But we get ahead of the story.

Chris nicely warned Shawn, in the seaberth, that he was going to start the engine. A bit over an hour later, It was surprisingly calm just before a squall. No longer able to sleep, around 1700 Shawn poked her head up on deck to see why Yannie was now merely idling but hadn't yet been turned off. She found Chris pensively looking the direction we were going. And then, over Yannie's idle, heard thunder. There was a bit of wind (hence the engine had been throttled back), but when it became apparent that this massive darkness was not the same as our recent squalls, just before the rain washed over us, Chris made the pivotal call to come about. Chris turned Yannie off and then jibed with the 80% and all of a sudden we were headed back north. We both watched in disbelief as we sailed away from what we had just nearly entered. From our new vantage, we could see that this weather was very extensive, not only horizontally but vertically developed. It was massive with no space between ocean and cloud and no sky visible above. In a section now to our west, thunder continued to rumble repeatedly, but no lightning... Yet. The sun was setting and it was nearly our time to check in on the PacSea Net (if you look at the report we were headed almost due N) when a section to the NE of us flashed with light. It was followed by more sheet flashes of lightning. And then a particularly dark area suddenly flashed with a web of cloud to cloud lightning bolts. We raised the 3rd reef to make way upwind and not lose our easting, all the while racing to reach what appeared to be the edge of this system, where blue sky in the waning day once again became obvious.

We hemmed and hawed for a couple of hours about what to do as the storm slowly moved SW. No energy for cooking, Shawn made rice and topped it with a can of soup while Chris downloaded weather data now that propagation was improving with the darkness. At one point we dropped the jib and hove to in the light winds. After watching the lightning show behind us, we both began to feel too close and pulled the jib back up to continue away from the system. At about 2100 we tacked back toward our original SW direction, dropped the 80% and once again started drifting slowly toward our destination. The newest weather report was completely different than the 24-hrs previous. A trough had shown up, Tstorms forecast within 120-nm of its axis, which lay a mere 50-nm SW of us (good thing we hadn't motored any more)! Exhausted, Chris collapsed in bed, while Shawn stood an otherworldly watch in which angry clouds silently and rapidly moved around us. Mid watch sheet lightning appeared both to port and to starboard and then prayers were answered and the Tstorm activity finally disappeared. From another flurry of middle-of-the-night weather downloads, we were relieved to see that the trough had moved rapidly SE.

Over the past day, Chris spent a ton of energy pouring through our weather resources to figure out how to get the weather data we need for a the new area we are in (i.e. the South Pacific and its weather systems). We were aware that thunderstorm and convective cloud activity, are one of our biggest concerns while transiting this area in non-hurricane season. However, we were only familiar with the ITCZ, and it is not the only place convection activity occurs. There is also an area called the SPCZ (South Pacific Convergence Zone). From our crash course on this, we now know that like the ITCZ, it creates areas of low visibility, thunderstorms, and squall activity. In the height of it's season it can span all the way from French Polynesia to Vanuatu and is the largest generator of the South Pacific hurricanes (during the hurricane season). It is currently forecast to be at its northern terminus for this (non-hurricane) season, located just below Suvarrov, and last night's trough was likely associated with this phenomenon. Our thunderstorm experience reminded us not to grow complacent in our idyllic image of what sailing in the South Pacific should be, and instigated an effort to learn even more.

This morning dawned with clear sky and NE breeze. The dominant surface seas are still from the easterly direction, but a large long period WSW ground swell has definitely made it here. Along with the wind waves, we can see mountains of water raise us up and let us down again as sun shimmers on the water surface. Gorgeous. As we munch on delicious apple-cashew-chicken-salad along with our last cucumber for lunch, we hope the current forecast holds and clearing winds continue to fill in for the duration of our passage.

2 comments:

  1. Have my fingers and toes crossed that the improved weather continues until you make landfall in Suvarrov . . . . and may you keep sailing in the desired direction!

    Hugs and Purrs

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  2. Quinoa-artichoke-olive dinner?
    Apple-cashew-chicken-salad?
    Two showers a day (occasionally)?

    This sounds *exactly* like my life now. Except for the part about fleeing thunderstorms and being surrounded by water for thousands of miles in all directions.

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