SIGMET

Code 1 : CB/TS

VDPP SIGMET 3 VALID 070800/071200 UTC ZPPP-
VDPP PHNOMPENH FIR ISOL EMBD CB/TS FCST N OF N1230 W OF E10500 TOP FL390 MOV E/09KT WKN =

Decode 1 : CB/TS

• VDPP            : The ATS unit that serves Phnom Penh FIR
• SIGMET 3    : Hazardous en-route meteorological information N03 on 07th
• VALID 070800/071200 UTC  : Validity period from 0800Z on 07th to 1200Z on 07th
• ZPPP             : MWO that issues the SIGMET
• -                                                 : The separation the preamble of the text
• VDPP PHNOMPENH FIR    : VDPP is ICAO location indicator of Phnom Penh FIR
• ISOL EMBD CB/TS FCST    : CB/TS are individual and embedded in cloud layer are forecast
• N OF N1230 W OF E10500    : The position of CB/TS is a part of the FIR with reference to the North of 12º30’ North latitude and West of 105º00’ East longitude within Phnom Penh FIR
• TOP FL390    : The vertical extent of CB/TS is FL390 (or 39000ft)
• MOV E/09KT: The movement direction of CB/TS is Eastward and movement speed is 9kt
• WKN              : The expected intensity of CB/TS is weakening
• =                      : The end signal of the message

*** Some Notes on Decoding SIGMET :

• ISOL EMBD CB/TS OBS AT 0750Z : CB/TS are individual and embedded in cloud layers are observed at 0750Z on 07th
• BTN FL090/140 : The vertical extent of CB/TS is between FL090 (or 9000ft) and FL140 (or 14000ft)
• WI 90NM  : The horizontal extent of CB/TS is within 90 nautical miles
• STNR         : The expected movement (forecast) or movement (observe) of CB/TS is no movement
• INTSF        : The expected (forecast) intensity or intensity (observe) of CB/TS is intensifying
• NC              : The expected (forecast) intensity or intensity (observe) of CB/TS is no change

Code 2 : TROPICAL STORM

VHHK SIGMET 2 VALID 200900/201500 UTC VHHH-
VHHK HONG KONG CTA TC KONI OBS AT 0600Z N1618 E11506 CB TOP FL500 WI 90NM OF CENTER MOV NW 8KT NC FCST 1500Z TC CENTER N1749 E11347 =

Decode 2 : TROPICAL STORM

• VHHK               : The ATS unit that serves HONG KONG CTA
• SIGMET 2        : Hazardous en-route meteorological information N02 on 20th
• VALID 200900/201500 UTC : Validity period from 0900Z on 20th to 1500Z on 20th
• VHHH               : MWO that issues the SIGMET
• -                          : The separation the preamble of the text
• VHHK HONG KONG CTA : VHHK is ICAO location indicator of HONG KONG CTA
• TC KONI          : Name of Tropical Cyclone is KONI
• OBS AT 0000Z : TC is observed at 0600Z on 20th
• N1618 E11506   : The position of TC center is given by 16º18’ North latitude and 115º06 East longitude
• CB TOP FL500 : The vertical extent of CB around the TC center is FL500 (or 50000ft)
• WI 90NM           : The horizontal extent of CB around the TC center is within 90 nautical miles from TC center
• MOV NW 8KT  : The movement direction of TC center is Northwest and movement speed is 8kt
• NC                       : The expected intensity of TC center is no change
• FCST 1500Z TC CENTER N1749 E11347 : Forecast position of TC center at the end of validity at 1500Z on 20th is given by 17º49’ North latitude and 113º47’ East longitude
• =                           : The end signal of the message

Code 3 : VOLCANIC ASH (VA)

LIRR SIGMET 2 VALID 210615/211215 UTC LIMM-
LIRR ROMA FIR VA ERUPTION MT EYJAFJALLAJOKULL LOC N6338 W01937 VA CLD FCST AT 210600Z SFC/FL200 E OF LINE N3753 E01935 - N4114 E01330 - N4438 E01419 VA CLD FCST AT 211200Z SFC/FL200 N OF LINE N3717 E02017 - N3658 E01750 - N4028 E01532 =

Decode 3 : VOLCANIC ASH (VA)

• LIRR           : The ATS unit that serves ROMA FIR
• SIGMET 2  : Hazardous en-route meteorological information N02 on 21st
• VALID 210615/211215 UTC : Validity period from 0615Z on 21st to 1215Z on 21st
• LIMM          : MWO that issues the SIGMET
• -                     : The separation the preamble of the text
• LIRR ROMA FIR : LIRR is ICAO location indicator of ROMA FIR
• VA ERUPTION MT EYJAFJALLAJOKULL : Name of the volcano is Eyjafjallajokull

• LOC N6338 W01937 : Location of the volcano is followed by 63º38’ North latitude and 019º37’ West longitude
• VA CLD FCST AT 210600Z  : The volcanic ash cloud is forecast at 0600Z on 21st
• SFC/FL200                 : The vertical extent of VA from surface to FL200 (or 20000ft)
• E OF LINE N3750 E01935 – N4114 E01330 – N4438 E01419 : The horizontal extent of VA to the East of Line described with latitude/longitude of 3 following points:
                   • 37º50’ North latitude and 019º35’ East longitude
                   • 41º14’ North latitude and 013º30’ East longitude
                   • 44º38’ North latitude and 014º19’ East longitude
• VA CLD FCST AT 211200Z  : The volcanic ash cloud is forecast at 1200Z on 21st
• SFC/FL200     : The vertical extent of VA from surface to FL200 (or 20000ft)
• N OF LINE N3717 E02017 – N3657 E01750 – N4028 E01532 : The horizontal extent of VA to the North of Line described with latitude/longitude of 3 following points:
                    • 37º17’ North latitude and 020º17’ East longitude
                    • 36º57’ North latitude and 017º50’ East longitude
                    • 40º28’ North latitude and 015º32’ East longitude
• =                       : The end signal of the message