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Bermuda Endures Direct Hit from Nicole; Fierce Winds in Store for Pacific NW

By: Bob Henson 4:09 PM GMT on October 14, 2016

Hurricane Nicole continued to scurry across the open North Atlantic on Friday after hammering Bermuda while at Category 3 strength on Thursday. As of 11 am EDT, Nicole was located about 400 miles east-northeast of Bermuda, moving east-northeast at 18 mph with top sustained winds of 80 mph. Nicole is a massive storm: its hurricane-force winds extend up to 70 miles from its center, and tropical-storm-force winds out to 205 miles. Nicole should remain sizable and powerful even after it gradually evolves into a post-tropical cyclone this weekend, posing no additional threat to land. (Nicole may retain a warm core surrounded by cooler midlatitude air for some time.)

Bermuda is accustomed to hurricanes, though Nicole was among the few in recent decades to make a direct hit on the island nation of about 65,000 residents. (See our Wednesday post for more on Bermuda’s hurricane history.) As defined by the National Hurricane Center, landfall is when the center of a hurricane’s eye reaches land, and a direct hit is when at least part of a hurricane’s inner eyewall passes over land. Radar imagery showed that the center of Nicole’s large eye just missed Bermuda, passing less than 10 miles to its southeast; satellite imagery made it appear the eye was further away because of the hurricane’s tilt from southwest to northeast with height. Since Nicole’s eye was so large, virtually all of Bermuda got the “eye experience”: winds suddenly becoming calm or very light, with birds chirping in the background.

Figure 1. Radar image of Hurricane Nicole at 1524Z (12: local time) Thursday, October 13, 2016, as the large, ragged eye (at least 50 km or 30 miles wide) encompassed the entire island, which is partially visible just to the west of the crosshatch at center that denotes the radar location. Image credit: Brian McNoldy, University of Miami, Rosenstiel School.

Figure 2. A tiki bar lays in a shamble following Hurricane Nicole, in Tobacco Bay, St. Georges, Bermuda, Thursday, October 13, 2016. Image credit: AP Photo/Mark Tatem.

The northern eyewall of Nicole tore across Bermuda at full strength, with a lesser hit from the western eyewall after the eye passed overhead. Sustained winds peaked at 87 knots (100 mph) with gusts to 111 knots (128 mph) at a Windguru observation site at Commissioner’s Point on the northwest tip of Bermuda, according to James Dodgson, deputy director of the Bermuda Weather Service. A newer low-level reporting site, installed for the upcoming America’s Cup at Pearl Island in central Bermuda, recorded 76-knot (87-mph) sustained winds, gusting to 103 knots (119 mph). (Thanks to James Dodgson for these preliminary data.) Tidal data from Esso Pier, on the south side of Bermuda’s St. Georges Island, indicate a peak storm surge of 3.73 feet at 1:30 pm Thursday local time.

Nicole’s fury caused remarkably little damage on Bermuda, a sign of the island’s resilient buildings and infrastructure. Bermuda’s national security minister, Jeff Baron, said there was significant flooding and severe road damage at points around the island, along with downed trees and power lines, according to weather.com.

Figure 3. Hurricane Nicole as captured by the MODIS instrument (Moderate Resolution Imaging Spectroradiometer) aboard NASA’s Aqua satellite at 1750Z (1:50 pm EDT) Wednesday, October 12, 2016, as Nicole was approaching Bermuda (visible as a dark spot at upper right of image). Image credit: NASA Goddard MODIS Rapid Response Team.

Potential once-in-a-decade windstorm takes shape for Pacific Northwest
The remnants of Typhoon Songda, now pushing east through the North Pacific alongside a very strong branch of the polar jet stream (see FIgure 4 below], will spring back to life this weekend in the form of an intensifying midlatitude cyclone expected to sweep near or over the west coast of Washington. The Pacific Northwest is prone to occasional damaging windstorms caused by strong midlatitude cyclones that arc northward along the coast. According to the National Weather Service in Seattle, this storm has the potential to be the worst for the region since the Hanukkah Eve windstorm of December 14-15, 2006. Arriving on the heels of weeks of record-heavy rainfall, that storm knocked out power to more than 1.8 million people (in some cases for several days) and caused damage of more than $250 million in the U.S. and more than $80 million in Canada. Other major storms in the Pacific Northwest include the Inaugural Day Storm of January 20, 1993; the February 13, 1979 storm; and the infamous Columbus Day Storm of October 12, 1962, which produced gusts to 116 mph in Portland, Oregon, and 88 mph at Tacoma, Washington (see Figures 5 and 6 below).

This weekend’s storm--already informally dubbed the Ides of October storm--is expected to develop on Saturday west of Oregon and move north-northeast to near or over the Olympic Peninsula of Washington on Saturday night. The GFS and European models agree that its central pressure will be in the range of 965 to 975 millibars near the Washington coast, comparable to the central pressures of many Category 1 and 2 hurricanes. There are still significant differences between models on the exact track and strength of the storm, and these could have big implications for the weather that results. “If our track is off by 100 miles, the forecast is radically changed at nearly all locations,” cautioned Cliff Mass (University of Washington) in a Thursday blog post. High Wind Watches for Saturday night warned of the potential for 20 - 40 mph winds in Seattle, with gusts to 65 mph in both Seattle and Portland. Similar winds could affect Vancouver, BC, depending on the storm’s track. Much higher winds will strike the Pacific Northwest at elevation, where gusts could easily exceed 100 mph.

Figure 4. The windstorm expected to strike the Pacific Northwest over the weekend will develop on the nose of a powerful jet stream segment across the central and eastern North Pacific. Sustained winds at the 250-millibar level (about 34,000 feet) will exceed 160 mph across more than 1000 miles of the jet core, with peak winds at the jet-stream level possibly topping 200 mph. Wind legend at right is in knots; multiply by 1.15 for mph. Image credit: tropicaltidbits.com.

More than wind
This weekend’s storm will be the most dramatic segment in a multi-day episode of heavy rain, high wind, and flooding along and near the Pacific Coast from northern California to British Columbia. The first salvo, on Thursday night into Friday morning, brought winds gusting as high as 55 mph in coastal Washington, along with widespread rains of 2” - 3” on the coast and more than 5” in the Olympic Mountains. More than 10,000 customers were still without power Friday morning on British Columbia’s Vancouver Island after Thursday night's powerful winds.

From Friday morning through early next week, coastal locations and coast-facing slopes could receive anywhere from 8” to 14” of additional rainfall, with especially heavy amounts likely over extreme northwest California and far southwest Oregon. The moisture will extend into parts of central California, where the Sierra Nevada will get its first major storm of the year (mostly in the form of rain, though). San Francisco could pick up an inch or more, which would make for its heaviest rain event since more than 3” fell on March 9-13.

Sarika heading toward Philippines
Our next tropical cyclone of significance to land areas is Tropical Storm Sarika, which is expected to reach at least Category 1 typhoon strength as it rolls across the northern Philippines. Sarika may continue intensifying early next week as it heads toward Southeast Asia, potentially affecting Vietnam by midweek.

See our Thursday evening post for more details on our blog’s new name, Category 6. We’ll be back on Monday with our next post. Have a great weekend, everyone!

Bob Henson

Figure 5. Damage from the Columbus Day Storm of 1962 in Seattle, WA. Image credit: Seattle Municipal Archives.

Figure 6. Damage from the Columbus Day Storm of 1962 in Newberg, Oregon. Image credit: National Weather Service/Wikimedia Commons.

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