Typhoon Fran

Typhoon Fran, known in the Philippines as Typhoon Reming, produced tremendous rainfall in Japan including, at the time, a national 24-hour record accumulation of . Forming as a tropical depression on September 3 to the southeast of Guam, Fran steadily intensified as it moved along a general northwest track. After brushing Guam two days later, the system achieved typhoon status on September 6 after the formation of an eye. A period of explosive intensification ensued thereafter and Fran reached its peak as a Category 4-equivalent typhoon with winds of the following day. Gradual weakening began on September 8 as it neared the Ryukyu Islands, and the system subsequently meandered near the islands for two days before striking Kyushu on September 12. It then moved over the Sea of Japan where it transitioned into an extratropical cyclone and ultimately dissipated on September 16.

Regarded as the worst typhoon in ten years, nearly a week of continuous rains caused disastrous flooding and landslides across Japan. Accumulations peaks at in Hiso, Tokushima. More than 325,000 people were forced to evacuate their homes and transportation was crippled. Nearly half a million homes were damaged or destroyed, leaving 300,000 people homeless. Many residents required rooftop rescue by helicopter. All told, the typhoon killed 169 people and left at least US$660 million in damage throughout its path.

Meteorological history

In early September 1976, an area of convection was identified within a monsoon trough to the northeast of Pohnpei. Traveling west, the system gradually developed and was classified as a tropical depression—the seventeenth of the season—at 12:00  UTC on September 3 by the Joint Typhoon Warning Center (JTWC). At this time, the depression was located roughly southeast of Guam. Situated near a weakness in a subtropical ridge (located south of Japan), the incipient depression turned northwest and gained strength. Aircraft reconnaissance found the system to have achieved tropical storm status by 03:39 UTC the next day, measuring a central pressure of 997 hPa (mbar; 29.44 inHg). At this time, the system was assigned the name ''Fran''. On September 5, Fran brushed the Mariana Islands to the southwest, passing west of Guam. Intensification began in earnest on September 6 as a wide eye developed, signaling Fran's rise to typhoon status. Upper-level conditions, including two anticyclones to the north and east, temporarily hindered additional strengthening by suppressing the typhoon's outflow.

During the latter part of September 6, the aforementioned hindering features quickly subsided, allowing for ample ventilation of the storm and enabled a period of explosive intensification. Aided by a shortwave trough over central China, Fran's outflow dramatically improved. In a roughly 24-hour span from September 6–7, Fran's central pressure plummeted from 977 hPa (mbar; 28.85 inHg) to . This included a drop of 43 hPa (mbar; 1.27 inHg) in 12 hours. Fran achieved its peak maximum sustained winds of at 12:00 UTC, classifying it as a Category 4-equivalent on the Saffir–Simpson hurricane scale. The storm also entered the Philippine Area of Responsibility around this time, prompting PAGASA to assign it with the local name ''Reming''. A subsequent reanalysis, though not yet integrated into JTWC's official track, determined Fran to have been slightly weaker with winds of . Though conditions remained highly favorable, Fran entered a near-steady state at this point with its pressure decreasingly slightly to its lowest observed value of 913 hPa (mbar; 26.96 inHg) at 21:09 UTC. At this time, Fran was an unusually large cyclone with gale. The previously beneficial shortwave trough bypassed the typhoon on September 8 and allowed for increased wind shear from an anticyclone to the west to impact Fran. This resulted in slow weakening of the storm. Rounding the edge of a separate trough, Fran also began a northward turn that directed it at the Ryukyu Islands of Japan.

Between 12:00 and 18:00 UTC on September 9, the eye of Fran passed between Okinoerabujima and Tokunoshima. Continual back and forth shifting of a trough north of the typhoon caused Fran to slow to a crawl by September 10. For the next day, Fran moved erratically along the western edge of the Tokara Islands, southwest of Kyushu, all the while battering the region with torrential rain and damaging winds. A deepening trough over China pushed the weakening typhoon northeast on September 11, with Fran eventually making landfall over Nagasaki Prefecture between 12:00 and 18:00 UTC on September 12. Winds up to were reported in Nagasaki City. After losing typhoon strength, Fran emerged over the Sea of Japan where cooler waters spurred its transition into an extratropical cyclone by 06:00 UTC on September 13. The remnant system continued northward, brushing Primorsky Krai, Russia, before turning back to the south. On September 14, multiple vessels encountered gale

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