General Information

Climate

Although the country is in the monsoon region, it is arid; except for the southern slopes of the Himalayas and the sub-Mountainous tracts which have a rainfall from 76 to 127 cm. on the southern ranges of the Himalayas, 127 cm. of precipitation takes place, while under the lee of these mountains (Gilgit and Baltistan) rainfall is hardly 16 cm. Rainfall also occurs from western cyclonic disturbances originating in the Mediterranean.  It is appreciable in the western mountains and the immediate for lying area; here the rainfall average ranges from 27 to 76 cm. The contribution of these western disturbances to rainfall over the plains is about 4 cm. A large part of the precipitation in the northern mountain system is in the form of snow which feeds the rivers. The all-pervasive aridity over most of Pakistan, the predominant power on the life and habitat of the people, coupled with the climatic rhythm, characteristic of a monsoon climate, are conducive to homogeneity of the land.

 Seasons in Pakistan are:-

Cold season (December to March). 
(ii) Hot season (April to June). 
(iii) Monsoon season (July to September). 
(iv) Post-Monsoon season (October and November).

 The cold season sets in by the middle of December. This period is characterized by fine weather, bracing air-low humidity and large diurnal range of temperature. Winter disturbances in this season accordingly cause fairly widespread rain. Average minimum and maximum temperatures are 4 oC and 18 oC, though on occasions the mercury falls well below freezing point. The winter sun is glorious. The hot season is usually dry. Relative humidity in May and June varies from 50 per cent in the morning to 25 per cent or less in the afternoon. The temperature soars to 40 oC and beyond. The highest recorded temperature at Jacob Abad in June is 53 oC. While the interior is blazing hot, the temperature along the sea Coast Ranges between 25 oC to 35 oC, but the humidity persists around 70 to 80 per cent. The south-west monsoon reaches Pakistan towards the beginning of July and establishes itself by the middle of the month. The strength of the monsoon current increases forms June to July; it then remains steady, and starts retreating towards the end of August, though occasionally, it continues to be active even in September when some of the highest floods of the Indus Basin have been recorded. From the middle of September to the middle of November is the transitory period which may be called the post-monsoon season. In October, the maximum temperature is of the order of 34 oC to 37 oC all over Pakistan, while the nights are fairly cool with the minimum temperature around 16 oC. In the month of November, both the maximum and the minimums temperatures fall by about 6 oC and the weather becomes pleasant. October and November are by far the driest months all over the plains of Pakistan.