Assessing the potential predictability of tropical cyclone activity in the Philippines on weekly timescales Marcelino Q. Villafuerte II 1 *, Tzu-Ting Lo 2 , Hsiao-Chung Tsai 3 , and Esperanza O. Cayanan 1 1 Department of Science and Technology – Philippine Atmospheric, Geophysical and Astronomical Services Administration, Quezon City, Philippines 2 Central Weather Bureau, Taipei, Taiwan 3 Tamkang University, New Taipei City, Taiwan This manuscript is submitted to “Terrestrial, Atmospheric and Oceanic Sciences” Running title: Extended-range TC prediction over the Philippines Three Key Points:  One- and two-week TC forecasts are evaluated  MJO affects TC predictability in 2015 and 2017 over the Philippines  Predictable TCs have similar characteristics with those occurring during El Niño events *Correspondence to: mvillafuerte@pagasa.dost.gov.ph; Telephone: (+63) 8284- 0800 Loc. (904); ORCID: 0000-0002-1620-4935 <Accepted Manuscript>