Warmer air becomes lighter and so it rises whereas cold air sinks.
Blowing of air decreases the pressure over the opening of the straw due to which the level of the soft drink in the straw rises up.
As air current move towards the poles from the equator, their temperature goes on decreasing. This is because of increase in altitudes. This decrease can be as less as $60$ degrees at the poles than at the equator.
One of the main reasons for this phenomenon is that the sun lies over head at the equator and it's rays are directly incident over it. While at the poles, it is present at a slant ans it's rays are incident at an angle.
As water is poured over the can, some steam in the can condense into water, reducing the amount of air inside. The pressure of the air inside the can decreases than the pressure exerted by the air from outside the can. As a result, the can gets compressed.A
A Cyclone alert or Cyclone watch is issued $48$ hours in advance of any expected storm and a Cyclone warning is issued $24$ hrs in advance.
Strong winds push water towards the shore even if the storm is hundreds of kilometres away. These are the first indications of an approaching cyclone. The water waves produced by the wind are so powerful that a person cannot overcome them. The low pressure in the eye lifts water surface in the centre. The rising water may be as high as $3 - 12$ metres. It appears like a water-wall moving towards the shore. High-speed winds accompany a cyclone.
In India, warnings regarding cyclones are issued by the meteorological department through $TV$, radio, or newspapers.
A Cyclone alert or Cyclone watch is issued $48$ hours in advance of any expected storm and a Cyclone warning is issued $24$ hrs in advance.