Meteorology for Instrument Flight in the Philippines
What this domain tests
Reading and acting on Philippine weather products: PAGASA forecasts, aerodrome METAR/TAF, SIGMET and AIRMET, plus the tropical hazards that actually generate missed approaches - convection, icing, wind shear and volcanic ash.
The products
METAR is observed; TAF is forecast; SPECI reports significant change; TREND is appended to some local reports. BECMG means a gradual, lasting change; TEMPO means temporary fluctuations. SIGMET warns of phenomena hazardous to all aircraft - cumulonimbus, severe turbulence, severe icing, tropical cyclone, and, distinctly Philippine, volcanic ash from Mayon, Taal or Kanlaon. MWO Manila issues the warnings; ATIS and VOLMET carry the local picture.
Seasonal pattern
Two monsoons dominate: the southwest monsoon (habagat, roughly June–September) brings widespread low cloud and rain, and the northeast monsoon (amihan, December–February) brings cooler, drier air and a lower freezing level. The ITCZ produces lines of CB, and tropical cyclones from the western Pacific are the main IFR disruption between July and November.
Worked example
Surface temperature 32 °C, standard lapse 2 °C per 1,000 ft. Freezing level ≈ 32 ÷ 2 × 1,000 = 16,000 ft. Climbing in cumulus at FL180 you are above the freezing level in a strong updraft, so supercooled water and airframe icing are likely even though the surface is hot; in a CB the freezing level can effectively be much higher in the core, and hail is possible in the anvil.
Traps
Treating a TEMPO group as a permanent change; assuming a METAR is a forecast for your ETA; thinking "tropical" means "no icing"; ignoring a volcanic ash SIGMET because the plume is downwind of the volcano, not overhead; using aerodrome weather instead of the alternate-minima rule for the ETA ±1 h window.