WSPA13 PHFO 040531 KZAK SIGMET ZULU 2 VALID 040525/040925 PHFO- OAKLAND OCEANIC FIR EMBD TS OBS AT 0530Z WI N0745 E16145 - N0845 E16515 - N0645 E16900 - N0430 E16600 - N0430 E16145 - N0745 E16145. TOP FL540. STNR. WKN. PLEASE ENSURE ALL FUTURE SIGMETS CONFORM TO THE FORMAT SPECIFIED IN ICAO ANNEX 3 CHAPTER 7 AND APPENDIX 6. REGARDS SADIS GATEWAY OPERATOR