Tropical Storm Noru

[Somerset Squall]

Tropical Storm 16W has formed around 500 miles east-southeast of Iwo To. Intensity is at 40kts and 16W should shortly receive a name from JMA. Central convection is quite deep, with formative banding features to the south of the LLC. Further strengthening is expected as waters are warm and shear is low. 16W should move to the north for the next 72hrs along the western periphery of a subtropical steering ridge to the east. After this time, 16W should curve northeastwards into the mid-lattitude westerlies and begin extratropical transition. 16W is currently of no threat to land.

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[Somerset Squall]

16W has become Tropical Storm Noru, with intensity rising to 45kts. Noru has been moving remarkably quickly, at one point the storm was moving to the north at a speed of 35kts! Noru has slowed to a speed of 21kts now, which is still twice as fast as the average tropical cyclone moves. The foward speed has prevented the storm from intensifying much, with some decoupling of the low and mid level centres occuring at times. Currently, the LLC is partially exposed as centralised convection is lacking. Noru probably won't strengthen much more as shear will increase tomorrow and the fast northerly motion will already bring Noru over colder water. Extratropical transition should be complete in 72hrs time.

[Somerset Squall]

Noru has weakened to 35kts. The reason for this is that an upper level low (ULL) has developed over the storm supressing outflow and therefore choking convection. Noru is not expected to restrengthen as shear is still set to increase tomorrow and sea temps will begin to cool on the continued northerly track.

[Somerset Squall]

Noru has continued to become involved with the ULL, and JTWC say that as a result, Noru has become a hybrid/subtropical storm. The completely exposed LLC still as 35kt winds around the periphery, but slack winds centrally. Convection is scarce due to the ULL causing dry and subsident air to choke the LLC. Noru should become completely extratropical soon on the northerly track.