Very interesting Ping, We also may have encountered something similar on our trip to Pueto Mont in October 2007. From memory we had building NE gradually backing through to NW. Fortunately it was pretty short and sweet, for a few hours the wind
sat around 50 knots and the baro plummeted like a stone, but the seas never built up into anything nasty, which makes sense for a small rapidly developing low.
I really enjoyed reading the account of Varuna's Storm. Appendix two and three are also worth a read, they show that not really that much has changed, still debates about heaving to vs sea anchors vs running off. A great find, and I'll have to make time to download and read the whole book on my kindle. Looks like heaving too didn't work
too well for him as the wind
increased, and he ended up lying ahull then running off under bare poles, finally towing a series of warps.
At one point he talks about the 'booming' noise
from distant breakers. I heard that once. A scary sound much like thunder. Never heard anyone alse mention this.
I spent a few years as mate on a 100 foot Brigantine. I take my hat off to him sailing her so short handed. Though in many ways the square rig is pretty easy to handle.