Douglas pulling away.
National Weather Service
Copyright © 2020
by Ralph F. Couey
It's been a day of tense anticipation, moments of dread, even fear, and finally a collective sigh of relief. As I write this, Hurricane Douglas is passing Kaua'i, the northernmost main island headed for obscurity in the vast reaches of the North Pacific Ocean.
At noon today, the outlook was not good. The storm had zigged to the south which put it's forecasted path across the center of all eight islands. What happened is an excellent tutorial on the exigencies of Pacific cyclones.
The Pacific is a vast laboratory of meteorology, ranging from the chill waters of the Gulf of Alaska, through the constant storms of the Inter-Tropical Comvergence Zone at the equator and all the way down to where its waters wash up against the ice of Antarctica. It is the largest ocean on this planet, 63.8 million square miles. For the past few days, Douglas had been steered by a ridge of high pressure a thousand miles north of Hawai'i. The pressure from that ridge kept Douglas on a consistent WNW path (290 degrees, for you compass fans). But starting yesterday, a weakness developed in that ridge. As a result, the hurricane turned in a more northerly direction. The difference was only five degrees, but it was enough. The storm passed so far north of the Big Island, that they were taken completely out of the cone. It continued to trend in that direction, dumping heavy rains on Maui and Lana'i -- but nowhere near the precipitation that had been anticipated.
But once past Lana'i, Douglas zigged back to the west. It looked for all the world like O'ahu was going to get nailed.
I left for work about 1:30, because the forecast indicated that tropical storm-force winds would arrive here by 2:00 pm. As I drove in, the air was completely calm but heavy with humidity. There was absolutely no wind. A novelist might have described it as the brooding quiet before the storm. It was heavily overcast and I could see a rain band streaming off the Ko'olau mountains. I arrived in the Warning Point just before 2:30. As we watched the satellite loop, we could see that the storm had taken a strong turn back to the north. That trend continued for the next three hours, and we could see that the storm center was going to miss O'ahu, passing some 65 miles north of Kahuku Point, the far northern tip of the island. Some strong rain bands swept across the north shore, and there was some significant surf action, but here in Diamond Head Crater, the flags hung limply on the pole.
Over the next two hours, it became obvious that Douglas had missed this island. Now, the concern focused on Kaua'i. None of the vaunted experts at the National Weather Service or the Central Pacific Hurricane Center could say for sure what was going to happen. In the past, hurricanes have avoided the other islands, but vented their wrath on the Garden Isle.
While this was going on, the hurricane warnings issued for the other islands were rescinded. Everyone was holding their breath, when it happened again.
The storm took a sudden and obvious turn to the north. It is almost midnight here, and the storm center is now positioned due north of Kaua'i. The infrared satellite image looks angry enough, but checking current weather for Princeville and Lihue, the two main towns on the north and east coast, show no rain falling at the moment, and winds ranging from 10 to 20 mph, really just typical tradewind weather. There is still the chance for significant rain, as moisture is dragged over the island by the hurricane's inflow. But the disaster that was breathlessly anticipated became something of a nothing burger.
The last pass of the Hurricane Hunter C-130 aircraft discovered that despite the cooler waters and a strong wind shear off the mountains of all the islands, the storm actually strengthened, increasing wind speed from 80 to 90 mph. But in another two hours or so, the storm will lift clear of Kaua'i and leave the Hawai'ian chain behind as it churns into the empty ocean to the northwest.
We moved the Warning Point from our usual place back into the steel-reinforced bunker of the Emergency Operations Center (unnecessarily, as it turned out.). Thus we were co-located with the Emergency Response Teams who populate the EOC when we are fully activated. When it became apparent that the first seven islands had dodged the proverbial bullet, the sense of relief in the bunker was palpable. All eyes were on Kaua'i, and they had prepared for any emergency support needed. Now, it looks like all will be well. Tomorrow, when this is all well and truly over, we can return to the battle we've fought for the past four months against the Novel Corona Virus and it's associated illness, COVID-19.
Predicting weather, despite all the 21st century's newest technology, satellites, doppler radar, computer modeling, complicated math, and the bright minds of meteorologists still remains pretty much a crapshoot. What we learned in the process of tracking Douglas was how meteorological events far away can have a strong effect on the local weather. Mind you, it could have gone the other way. If that ridge to the north had strengthened, then the storm would have steered a more southerly track, and instead of this tale, you'd be reading about a trail of destruction, and possibly, death.
Thankfully, it didn't happen this time. But there will be a next time. Count on it.
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