Cumulonimbus Storm Clouds.
- Cloud structure.
- Organised convection.
- Steering/Calmer bands.
- Clouds and steering.
- 500mb charting that steers.
- Doppler radar MCV.
Due to the wide sea expanses of the Asian Sub-Tropical and Tropical environments one is sure to find this following cloud type The Cumulonimbus cloud unmistakable due to its towering cloud structure. Remember on our lesson of how a heated water molecule when left undisturbed will then become highly buoyant (rising). Once this molecule then rises into a cooler lower mid to upper level and continues rising then cloud droplets will form. Add into this mixture the convection that we also explained when the heated air molecule becomes unstable?. These are the perfect ingredients for this type of cloud structure to form the Cumulonimbus.
The Cumulonimbus cloud structure.
Within this cloud you will find the following effects:
- Heavy Rain sheets at the area of the clouds downpours being strong rains for short bursts of your typical cumulonimbus structure also called Heavy brief Showers.
- Hail (Only if a cold middle to lower layer exists this might not be possible in a sub-tropical/tropical setting in summer).
- Convection will be present in clouds of this thunderstorm type, you will know by the loud thunderclaps and lightning strokes more present at afternoon, night.
- Turbulence being that at different altitude levels the air currents are in different speeds and directions (unstable air flow). Usually in the center of the cloud system going up vertical.
- Clouds spanning across up to 7 Kilometers maximum.
- Vertical cloud tops up to 39,000 ft normally although some powerful systems go higher.
- The unmistakable towering vertical cloud structure.
- A possibility of lift in surface winds especially at the outflow area that may severely affect camping, outdoor events and air flights. The direction of these winds are Upwards (Updraft), Downwards (Microburst, Downdraft ), and Cyclonic (Coriolis effect in a group of clouds ).
- The trait of producing Gust Fronts, and Powerful surface gusts, and Powerful straight line winds from Squall Lines if the ingredients to produce cumulonimbus clouds are in place.
Organised convection families.
It becomes also important to realise these cloud structures sometimes are made as single systems, can become part of a group of a MCV or Supercell or A squall line and finally form the Walls inside a Hurricane/Cyclone/Typhoon. These convective systems are part of an organised thunderstorm engine family and can sometimes last for days when the ingredients are correct and in place at the right time. The author is quite skilled in understanding the convective composition of these systems. A MCV is of particular note as these are difficult to forecast but they are known to last for up 7 days and can create active inland storms. The Cumulonimbus Cloud forms the main cloud type of this convective family (MCV Storm Engine) and the other types mentioned.
Weak banding/Steering.
At 500mb is the steering winds important as the air current direction and speed here will determine if a MCV and the towering Cumulomibus clouds are slow moving as the Asian Tropics and South Sub Tropics are in a variable state of change at times. In the band from the Calms of cancer south to the ITCZ sometimes will demonstrate weak winds and bouyancy that allow MCV creation. The MCV may follow the path best defined by the 500mb wind direction in the area of the MCV in this scenario. Summer in Asia is the ideal time for formation of the MCV due to surface heating and air parcel buoyancy.
Cumulonimbus Steering.
The direction of 500mb air currents is controlled by the opposites attract equation in that High Pressure always moves towards Low pressure. As the pressure difference between highs and lows are weak in the South Sub Tropical/Tropical band in summer then the winds become weaker but still directional at 21,000 ft the wind altitude that determines the direction of weather in the Asian Tropics/South Sub Tropics. The direction these 21,000ft winds are moving to then dictates the direction the MCV will move towards and the towering cumulonimbus clouds that accompany them. For the ordinary laymen a news forecast/radio report or online service may help to inform of there presence in the area.
Storm on the move 500mb.
