On October 17, 2013, Typhoon Francisco skirted Guam, but the storm was on a trajectory that could bring it toward Japan next week. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured this true-color image of the strengthening storm at 2:05 p.m. local time (04:05 UTC).
At that time, the storm had maximum sustained winds near 98 mph (257 km/h), a large cloud-filled eye and sprawling rain bands that brought heavy rains to Guam, which can be seen in the northeast quadrant of the storm. The center was located about 147 nautical miles southwest of Guam, near 12.5°N and 143.1°E.
Typhoon Francisco intensified rapidly over the next two days, becoming Super Typhoon Francisco on October 18 and reaching peak maximum sustained wind speeds of 160 mph (157 km/h) on October 19. Late on October 20 the storm was weakening, with winds dropping to 135 mph (217 km/h). Although this reduced the storm to Typhoon status, it still was a major storm, with winds compatible with a Category 4 storm on the Saffir-Simpson hurricane wind scale.
According to the Joint Typhoon Warning Center (JTWC), Typhoon Francisco should continue on its weakening trend over the next several days, and should begin transition to an extra-tropical system on about October 24. Meanwhile, however, Francisco is taking aim at eastern Japan, and it is predicted to strike that country on October 23. However, due to uncertainties in the mechanisms at work steering the storm (primarily in vertical wind shear and sea surface temperatures), JTWC cautions that the confidence in the forecast remains low.