Satellite weather images

[Ref Weather Flying, Fifth Edition 35/382] Application and limitations of different weather images Infrared is used to give temperatures of the clouds. That’s how meteorologists tell tops; Water vapor satellite images display water vapor quantity in the middle to upper troposphere, (700–200 millibars [mb], or about 11,000 feet on up to about 39,000 feet). The image’s […]

Hail (Met)

[Ref ISBN978-1-56027-901-3, Pilot’s Handbook of Aeronautical Knowledge, FAA-H-8083-25B Page 12-17] Hail is a type of precipitation and is an indication of CB Supercooled drops above the freezing level begin to freeze. Once a drop has frozen, other drops latch on and freeze to it, so the hailstone grows—sometimes into a huge ice ball. Eventually, the hailstones fall, […]

Thunderstorm icing

[Ref Pilot’s Handbook of Aeronautical Knowledge, FAA-H-8083-25B Page 12-24] Updrafts in a thunderstorm support abundant liquid water with relatively large droplet sizes in the upward current. When water content carried above the freezing level, the water becomes supercooled. When temperature in the upward current cools to about –15 °C, much of the remaining water vapor sublimates […]

“funnel cloud” vs “tornado” vs “waterspout”

[Ref Pilot’s Handbook of Aeronautical Knowledge, FAA-H-8083-25B Page 12-23] What’s funnel cloud, tornado and waterspout ? All this three weather phenomena are high-speed vortex extending downward from the cumulonimbus base, and the difference is that: Funnel cloud does not reach the surface; Tornado touches a land surface; Waterspout touches a water surface Formation of funnel cloud Should the air being […]

“Typhoons”, “Cyclones”, “Hurricanes” – all are Tropical storms !

[Ref Understanding Weather & Climate, Books a la Carte Edition (6th Edition) #ISBN-13: 978-0321773227 #ISBN-10: 0321773225] Tropical storms have different names depending on where they occur Extreme Western Pacific –  Typhoons Indian Ocean and Australia – Cyclones Atlantic and Eastern Pacific – Hurricanes (Hurricanes are refer to any storm, regardless of location) In structure, these […]

clouds of operational significance (對飛行有重要影響的雲)

[Ref Jeppesen, HKO, SKYbrary] What’s “clouds of operational significance”? CLOUD OF OPERATIONAL SIGNIFICANCE — A cloud with the height of cloud base:        a)  below 1500m (< 5000ft); OR b) below the highest minimum sector altitude a) or b) – whichever is greater,OR a cumulonimbus cloud (CB) at any height; OR a towering cumulus cloud (TCU) at any height    

Ceiling (Met)

[Ref Pilot’s Handbook of Aeronautical Knowledge, FAA-H-8083-25B Page 12-17,  Jeppesen] What’s ceiling (cloud)? The height above the ground or water of the base of the lowest layer of cloud below 6000m ( < 20,000ft) covering more than half the sky – over five-eights – reported as “broken”, “overcast”, or “obscuration” Notes: obscuration refers to fog or haze.     #ceiling #cloud #met Read More – # Current […]