What’s Lee side?
May 26, 2024
Ref Windward and leeward – Wikipedia The term “windward” has roots in both Low German and Old English. The word “lee“, which means a place without wind. Windward is upwind from the point of reference, i.e., towards the direction from which the wind is coming; Leeward is downwind from the point of reference, i.e., along the direction towards
How the air pressure work in our environment?
May 26, 2024
By change, I stumble upon a series of televsion show, which use animation to explain Meteorology in a easy way. Great!
Cloud Base v.s Cloud Ceiling
May 25, 2024
A cloud base refers to the lowest visible part of the clouds over the station. A cloud ceiling refers to the distance between the ground or water and the base of the lowest layer of clouds, which must form a cloud cover that blankets more than half of the sky below 20,000 feet. Read More –
What’s Sea Breeze and Land Breeze?
May 25, 2024
NWS JetStream – The Sea Breeze (weather.gov) Sea breeze and Land breeze are kind of convective current Day time 地球吸熱是greenhouse effect Night time 地球放熱是radiation cooling The sea breeze circulation is composed of two opposing flows; one at the surface (called the sea breeze) and one aloft (which is a return flow). These two
Sunrise, Sunset and Rainbow, Northern lights (aurora borealis)
May 25, 2024
Why sunsets organge? Ans: Scattering effect! How are rainbows formed? – Met Office How Are Rainbows Formed? | Royal Meteorological Society (rmets.org) Northern lights – Met Office
What’s Microbust?
May 23, 2024
Read more – Turbulence v.s Wind Shear – Tommy’s Diaries (tommykwan.com)
What’s Solar insolation?
May 22, 2024
The weather on our mother earth is starting from the energy of the sun. So, how the energy of sun can reach the earth? To more specific, weather is basically the result of temperature differences! Another useful footage for us to learn about the basic background of temperature difference on the earth Read more –
What’s Trough of Low 「低壓槽」？
May 21, 2024
Ref https://www.hko.gov.hk/en/education/weather/wind-and-pressure/00117-introduction-to-air-pressure-part-ii.html A trough of low pressure is an extended area of low pressure. On the weather chart, it has associated with it a trough line. The pressure there is lower than that at neighbouring points on either side of the trough line. Monsoon low pressure v.s Tropical cyclone
一次搞清楚Ceiling
April 6, 2024
Ref FAA-H-8083-25C version 2023 5-24, 7-12, 11-8,12-17 Ceiling related to metrology? Ceiling is the lowest layer of clouds reported as being broken (5/8) or overcast (8/8) OR the vertical visibility into an obscuration like fog or haze Ceiling related aircraft performance? absolute ceiling : the altitude at which the aircraft has no excess
When the air is stable?
April 5, 2024
Ref: https://skybrary.aero/articles/lapse-rate 到底咩情況下parcel of air 叫stable? To answer this question, we need understand few concept: 咩係Lapse rate 咩係環境上面既Lapse rate 咩係pacel of air 既Lapse rate Lapse Rate is the rate at which temperature changes with height in the Atmosphere. In my language, how many degree Celsius drop when vertical distance increase for a fixed number.
What’s Monsoon Wind ; Why Monsoon blow from north east in winter and southwest in summer?
April 5, 2024
Ref: https://www.hko.gov.hk/en/publica/gen_pub/files/sms_Urdu.pdf https://www.hko.gov.hk/en/education/weather/meteorology-basics/00010-geostrophic-wind.html https://www.hko.gov.hk/en/education/weather/monsoons/00068-why-the-winter-monsoon-in-hong-kong-is-generally-called-the-northeast-monsoon.html 所謂季候風就係會隨著季節改變既風, 但光是研究呢個季候風既風向都搞左我粒幾鐘, 因為背後講緊既CONCEPT 有好幾個: 咩叫High pressure system, 咩叫Low pressure system 咩係風 咩叫Coriolis effect (科里奧利力/科科氏力) 咩叫Geostrophic Wind (地轉風) 想簡單D咁理解就要背少少野 (明白少少基本CONCEPT) High, Low pressure system 是相對 (relative) : compare one air mass with another one 仲要記得通常凍就係有高壓區, 熱就係有低壓區~ 風就是due to two air mass has pressure difference and so the pressure gradient as
What’s CAVOK , What’s NCD, NSC
March 28, 2024
Reference source: https://skybrary.aero/articles/weather-observations-aerodromes CAVOK The visibility, RVR, weather and cloud groups are replaced by CAVOK (Cloud And Visibility OK) when the following conditions exist simultaneously: If there is no cloud below 5000 ft or below the highest minimum sector altitude (whichever is greater) and there is no towering cumulus or cumulonimbus, ‘NSC’ is reported. Note:
