In Pakistan the temperatures start rising after the spring equinox i.e. From 21st of March and the days start getting warmer day by day so that the averages of temperature of the months of April and onwards are much higher than the preceding months. On the plains the averages of temperature in June/July vary from with Jacobabad having recorded an absolute maximum. However, the humidity is low.
The high pressure which was located here in the cool season starts dissipating and is now replaced by a low pressure. The air when heated expands, becomes light and develops a low pressure area in south western part of Pakistan. With the change of pressure the direction of winds also changes; both the quantity and the duration of rainfall are very small.
However, the turbulence caused due to mixing of cool and warm air currents in the atmosphere results in causing convectional rains and brings relief from the hot and sultry weather for a short period in our northern regions falling between the hot and the cool seasons.