Historically Rare Tropical Storm Alaska-Canada Sep Oct Landfalls

Hurricane Walaka Track 0500 Hours October 3 2018
Hurricane Walaka Track 0500 Hours October 3 2018
September-October Central Pacific Tropical Storms 1842-2018
Sep-Oct Central Pacific Tropical Storms 1842-2018

Historically Rare Tropical Storm Alaska-Canada Sep Oct Landfalls  – Currently Hurricane Walaka is projected to make landfall in Alaska or British Columbia Canada later this month. North America landfalls in Canada or Alaska from tropical storms originating in the Central Pacific near Hawaii are somewhat rare.  Though, in recent years, they have become more common to track from Hawaii to  northwest North America.

In fact, since 1842, this similar tropical cyclone movement pattern has taken place only twice before, all three since 2014.  Only once before, has the storm actually made landfall in Northwest North America. While I am hesitant to use the term “Global Warming”, a 176 year history of central/ east Pacific storms tracking to Northwest North America is indicating that, Houston, we may have a problem.

“In October 2015, in an uncommon occurrence, a slow moving disturbance detached from a monsoon trough southeast of Hawaii and became Tropical Depression Seven-C on October 3. With a favorable environment, the storm became Tropical Storm Oho quickly after.With this, Oho became the record breaking twelfth storm this year to enter, or form in the Central Pacific.

Tropical Cyclone Oho Track October 2015
Tropical Cyclone Oho Track October 2015

Under southwesterly wind shear, Oho slowly intensified while accelerating northeastwards.While tracking northeastward, Oho became a Category 2 on October 7, attaining peak intensity of 110 mph and a pressure of 957 mbars.Shortly after its peak, Oho moved to an area with cooler ocean temperatures and increasing southwesterly wind shear, which caused the storm to weaken and to lose its tropical characteristics.

The storm became extratropical on October 8 and briefly weakened to a gale low on early October 9. However, due to strong baroclinicity, Ex-Oho briefly re-attained hurricane-force winds before starting a stead weakening.

On October 10, Oho’s remnants moved into Alaska as a moderate extratropical storm, where it weakened, until the system dissipated over western Canada 6 hours later.”

In October 2014, Tropical Storm Ana followed somewhat in the footsteps of Ono.  “An area of deep convection and a low pressure area merged and became Tropical Depression Two-C on October 13. It slowly intensified and turned northwestward, developing into Tropical Storm Ana. The storm continued intensifying and was upgraded to a strong tropical storm. Ana turned westward, strengthening into a Category 1 hurricane on October 17. As Ana kept south of the island chain, the hurricane produced large waves and winds. Consequently, the Central Pacific Hurricane Center initiated tropical storm watches. 

Tropical Cyclone Ana Tropical Cyclone Oho
Tropical Cyclone Ana Tropical Cyclone Oho

Beginning on October 15, various tropical cyclone warnings and watches were issued for Hawaii, starting with a tropical storm watch for the Big Island. Three days later, a tropical storm warning was issued for Kauai and Nihau, and was extended to include portions of the Papahānaumokuākea Marine National Monument. The threat of the storm forced parks and beaches to close in the state.

While passing south of Hawaii, Ana produced heavy rainfall on most of the islands, peaking at 11.67 in (296 mm) at Keaumo on the Big Island. The rains caused the Sand Island water treatment plant in Honolulu to overflow, which sent about 5,000 gallons of partially treated wastewater into Honolulu Harbor.

On October 25, Ana was downgraded to a tropical storm for the second time. Ana continued on a track to the northwest and weakened even further. The system eventually turned north and once again re-strengthened into a high-end tropical storm. Ana turned northwest and soon northeast, fluctuating in strength before being picked up by the jet stream. While racing off to the northeast at nearly 35 knots, Ana once again strengthened into a Category 1. After yet again being downgraded to a tropical storm, Ana became extratropical far to the northeast of Hawaii on October 26.”

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Recent Tropical Storms

Video: Hurricane Walaka October 3 2018