The 1961 Pacific typhoon season was an extremely active season, having a total of 35 tropical storms, with 20 of them reaching typhoon strength and 8 further strengthening into super typhoons, as well as an accumulated cyclone energy index of 365.6. The season had no official bounds; it ran year-round in 1961, but most tropical cyclones tend to form in the northwestern Pacific Ocean between June and December. These dates conventionally delimit the period of each year when most tropical cyclones form in the northwestern Pacific Ocean.
The scope of this article is limited to the Pacific Ocean, north of the equator, and west of the International Date Line. Storms that form east of the dateline and north of the equator are called hurricanes; see 1961 Pacific hurricane season. Tropical storms formed in the entire west pacific basin were assigned a name by the Joint Typhoon Warning Center. Tropical depressions in this basin had the "W" suffix added to their number.
Seasonal summary
Systems
Tropical Storm Rita
A tropical low developed from the ITCZ about 140 miles to the south of Eauripik on January 8. The low gradually deepened as it moved west-northwest during the following days. Early on January 14, the system organized itself enough to be classified as a tropical depression. The next day the depression strengthened into a tropical storm and was named Rita by the Joint Typhoon Warning Center. Rita reached a peak intensity of and a minimal surface pressure of on January 16. At this time a cold front to the north and a subtropical ridge positioned behind it forced the storm to turn sharply to the north-northeast. Rita began to, at this time, weaken, and became a depression on January 17. It remained a depression for the next three days. On January 19 Rita weakened to a remnant low and became attached to the tail-end of a passing front. By the 21 what was left of Rita became fully absorbed by the aforementioned front.
Rita stayed largely at sea with little to minor effects to Palau or to the Mariana Islands, besides some rain and squally weather.
Tropical Depression Susan
Susan was a short-lived tropical storm that didn't impact land.
Typhoon Tess
Between March 21 and 22, winds aloft and surface observations in Truk Atoll (now Chuuk Lagoon) indicated a weak tropical storm passing south of the atoll and was intensifying. A reconnaissance aircraft on March 23 indicated a weak circulation, with winds of about . The next day, another reconnaissance aircraft mission revealed Tess had winds of about , issuing the first alert on Tropical Storm Tess. On March 25, Tess upgraded to typhoon status south of Yap, with maximum surface winds of about . Reports from Yap indicated a minimum atmospheric pressure of . Tess began to recurve after passing Yap, and by March 28, Tess reached its peak intensity, with winds of about . After peaking peak intensity, Tess started to weaken, and recurved on March 30. The final advisory was issued on March 31, as winds fell below .
Some considerable damage was reported during the storm. On March 25 at 2255Z, maximum peak gusts reached . of rain fell during its passage, with no rise in tides. Preliminary reports showed some significant damage to trees and houses. No deaths were reported from Tess.
Tropical Depression Viola
Viola hit Vietnam as a tropical depression.
Typhoon Alice
Typhoon Alice formed to the east of the Philippines on the 17th of May. Alice quickly strengthened and passed directly over Hong Kong with gusts of 85 mph on the 18th before recurving through the Chinese Mainland. The hurricane signal was again like Mary in 1960, not strictly justified as sustained winds were far-fledged from hurricane force. Sustained winds in Hong Kong never reached hurricane force; maximum 60-minute winds reached 90 km/h in Waglan Island and 83 km/h at the RHKO. 4 people were killed and 20 people were injured in Hong Kong.
Typhoon Betty
On May 20, the precursor to Betty became a closed vortex south of Koror, Palau. On May 22, a reconnaissance aircraft mission indicated winds of about , causing them to issue a tropical storm warning. Later that day, a typhoon warning was issued. Betty moved northwest toward Taiwan at an average speed of . On May 25, Betty peaked with winds of , with a minimum atmospheric pressure of . Later that day, the typhoon passed less than west-southwest of Batan Island. Betty made landfall on Taiwan's east coast, with wind speeds of . It moved across the island at an average speed of . The storm recurved northeast and hit China's east coast, and then moved into Korea on May 28. At 1200Z on May 28, the last warning was issued as it transitioned into an extratropical storm.
In Batan Island, winds reached on May 25. Betty caused extensive damage to crops in Taiwan due to flooding.
Typhoon Cora
The origins of Cora can be traced a series of lows that formed on June 19. By June 22, the pressure dropped to , with winds of around , which led to the first warning as a tropical depression. Cora existed between a westerly flow near the equator and an anticyclone. Movement of Cora northward across this trough added an eastward component, and later a westerly component that became the predominant direction. Cora later intensified to typhoon strength and moved toward Vietnam. Between June 23 and 24, Cora had wind speeds of . The final warning was issued after Cora made landfall south of Vinh. Possible damage could have occurred to shipping or in small islands.
Tropical Storm 13W 13W was a short-lived weak tropical storm. It formed south of Japan on June 25. It made landfall in Japan and dissipated on June 29.
Tropical Storm Doris A tropical depression formed east of the Philippines on June 27. It traveled north-northwest and intensified into a tropical storm. It was named Doris. The storm made landfall in China, and continued to travel northwest to inland. The storm then turned northeast and went out sea. The storm dissipated on July 3.
Typhoon Elsie Elsie hit Taiwan and Guangdong.
Tropical Storm Flossie Flossie hit Luzon and Hong Kong as a tropical storm.
Tropical Depression Grace Grace formed on July 18. It traveled north and hit Korea.
Typhoon Helen
Helen hit Korea as a tropical storm.
Typhoon Ida
Ida hit Japan as a tropical depression.
Typhoon June
20 people were killed from heavy rain and mudslides, when 90 mph Typhoon June hit southeastern Taiwan on August 6.
JMA Tropical Storm Fourteen
The storm was short-lived and didn't make landfall.
Typhoon Kathy
Kathy hit Japan as a tropical storm.
Typhoon Lorna
Lorna formed on August 19 east of the Philippines. It rapidly intensified into a category 4 typhoon. Lorna weakened before making landfall in Taiwan and Fujian. The storm dissipated on August 27.
Tropical Storm Marie
On September 29, a tropical depression formed with 30-knot winds. The system tracked westwards, briefly intensifying into a tropical storm. The system made landfall on the Japanese island of Shikoku a tropical depression.EDIS, p. 21
Tropical Storm Olga
On September 4, a low developed off of the eastern coast of the Philippines. Upon crossing into the South China Sea, the low became more organized and started dropping in pressure. On September 8, the system was upgraded to a tropical storm. The system continued to strengthen, and on September 9, it was designated as a typhoon by the JTWC. Typhoon Olga made landfall 50 kilometers to the northeast of Hong Kong, killing 7 people, mostly due to landslides. The system rapidly deteriorated over land and dissipated 180 kilometers to the northwest of Hong Kong.NAA, p. 590
Typhoon Pamela
Typhoon Pamela, which formed on September 8, rapidly intensified to a peak of 180 mph on the 11th. Pamela weakened to a 145 mph typhoon by the time it hit eastern Taiwan late on the 11th, and after crossing the island and the Taiwan Strait, the storm hit eastern China as a 65 mph tropical storm. Pamela dissipated on the 12th, after causing 98 casualties (with 27 missing), $5 million in damage (1961 USD), and leaving 50,000 homeless.
Typhoon Nancy
Tropical Storm Nancy, having developed on September 7 in the open West Pacific, rapidly intensified to reach super typhoon status early on the 9th. Nancy continued to strengthen and reached peak winds of 215 mph (187 knots) on the 12th. Such intensity is speculative, as Reconnaissance Aircraft was in its infancy and most intensities were estimates. Furthermore, later analysis indicated that equipment likely overestimated Nancy's wind speed; if the measurements were correct, Nancy would have been tied with Hurricane Patricia for the highest wind speeds for a tropical cyclone on Earth. Regardless, Nancy was a formidable typhoon and retained super typhoon status until the 14th as it neared Okinawa. The typhoon turned to the northeast, and made landfall on southern Japan on the 16th with winds of 100 mph. It continued rapidly northeastward, and became extratropical on the 17th in the Sea of Okhotsk. Well executed warnings lessened Nancy's potential major impact, but the typhoon still caused 172 fatalities and widespread damage.
Tropical Storm Ruby
Ruby hit the Philippines and Vietnam.
Typhoon Sally
Sally hit China as a category 1 typhoon.
Typhoon Tilda
A circulation was first reported from a ship 300 miles west of Guam on September 26. The system then quickly intensified into a typhoon and made a northward turn directly towards Japan. During this period, a favorable environment allowed the typhoon to intensify to peak winds of 160 mph. The storm then turned westwards, passing 15 miles under Okinawa. The town of Naha, Okinawa received sustained winds of 85 mph with gusts of 120 mph. The much-weakened typhoon made landfall on the Chinese mainland 100 miles south of Shanghai on October 4. It caused 11 deaths, over $6 million in crop damage, and the Lebanese merchant ship Sheik ran aground off of Kitadaitōjima, killing 2. The Taiwanese military exercise Sky Soldier was canceled due to the typhoon. The system then recurved outwards due to westerly winds into the Sea of Japan with sustained winds of 30 mph. The remnants began an extratropical transition and dissipated in the Sea of Okhotsk.NAA, p.591
Typhoon Violet
Violet was first observed as a small circulation to the southwest of Marcus Island. On October 2, the system had organized enough to warrant further investigation. After a few days of observation, a report of tropical-storm-force winds was relayed back to the JTWC and on October 4, it was upgraded to Tropical Storm Violet. Violet took an unusual track, moving in a southern direction after formation. This was due to its location west of a high-pressure system, which the storm struggled to move around. After completing a curve to the south of the ridge, Violet quickly intensified into a typhoon. The movement of the subtropical ridge to the east resulted in Violet turning abruptly to the northwest. Violet continued to intensify and soon reached its peak intensity, on October 7, with sustained winds of and a minimal surface pressure of ; however, the wind readings during this era of reconnaissance were erroneously high. Violet moved in a smooth path northward and clipped the Boso Peninsula area of Japan, near Tokyo. After landfall, Violet began to transition into an extratropical cyclone and continued to move northward. By October 10, Violet had become fully extratropical.