Late on September 4, Noru's LLCC that remained partially exposed since formation unexpectedly became elongated and started weakening. However, data from an ASCAT scatterometer pass depicted that the LLCC had an expansive area of strong tropical storm force winds along the eastern and northern peripheries. A TUTT cell wrapped the east and northeastern sides of Noru suppressing its outflow. Soon, the convective banding, which was already fragmented started becoming disorganized causing Noru to start weakening. A new TUTT cell developed over the system and started restraining outflow. As a result, the LLCC became fully exposed and virtually lacked convection. The TUTT cell moved over Noru snuffing outflow in all directions and sheared the remnant central convection, prompting the JTWC to downgrade Noru to a tropical depression. However, data from an scatterometer pass depicted that Noru had winds of over near the center, prompting the JTWC to reupgrade the system to a tropical storm. On September 5, Noru started to appear like a hybrid system, primarily showing subtropical characteristics. The JTWC added that Noru was undergoing an extratropical transition and would become an extratropical cyclone within 24 hours. Noru continued to transition into an extratropical cyclone with a broadening LLCC and weaker winds at the core, being embedded in an upper-level trough that suppressed the formation of convection within the LLCC. With the extratropical transition well underway, Noru drifted into an area of low sea surface temperatures and started weakening, prompting the JTWC to downgrade Noru to a tropical depression. On September 6, Noru finished the extratropical transition becoming an extratropical cyclone east-southeast of Hokkaido, Japan, prompting the JMA and the JTWC to issue their final warning on the system. 