Pakistan’s Monsoon 2011 (July & August)
During the first two months of monsoon season (July & August), anomalous behavior of precipitation has been observed over Pakistan. Over the national scale, in July, slightly below normal (-18%) rain was recorded but highly above normal (+59%) precipitation occurred during the month of August. Rainfall deviation from normal (1961-1990) during July over the provinces, Khyber-Pakhtonkhwa and Punjab was minimal whereas, Balochistan & Sindh were largely in deficit i.e. -36% & -72%, respectively. The monsoon activity was intensified during August over the country, especially south eastern parts, where monthly rainfall was +270% above normal in the province of Sindh. The August rainfall was almost normal over Khyber-Pakhtonkhwa (+9%) and slightly above normal over Punjab (+17%) & Balochistan (+22%).
RAINFALL (Percentage Departure)
| Region | July | August |
|---|---|---|
| Pakistan | -17.7 | 58.9 |
| Khyber-PK | 0.8 | 8.8 |
| Punjab | 1.2 | 16.6 |
| Balochistan | -36.2 | 21.6 |
| Sindh | -72.1 | 271.4 |
In Pakistan the monsoon period is taken from July to September. The month wise percentage contribution to monsoon rainfall has been found to be generally 45, 40 & 15 during July, August & September respectively. The August monsoon rainfall, over province of Sindh (271 % above normal) is the heaviest recorded during the period 1961-2011. It may be recalled, that the monsoon rainfall during last year, over whole country, was excess of 87 per cent and was highest since 1994 and ranked second highest during last 50 years of period. These unusual & heavy downpours led to flash flooding in the area and caused damage to crops, property and tens of lost lives.
Chief amount of observed monthly accumulated rainfall (mm)
July 2011
| Station | Observed | Normal | Departure |
|---|---|---|---|
| Dahmial | 593.0 | —- | —- |
| Risalpur | 415.6 | 132.4 | 283.2 |
| Islamabad (AP) | 335.2 | 305.3 | 29.9 |
| Mianwali | 271.4 | 134.8 | 136.6 |
| Murree | 265.4 | 364.1 | -98.7 |
| Lahore (PBO) | 245.2 | 212.1 | 33.1 |
| Balakot | 228.3 | 372.0 | -143.7 |
| Kamra | 228.1 | —- | —- |
| Malam Jaba | 219.0 | —- | —- |
| Sialkot | 218.7 | 304.1 | -85.4 |
| Joharabad | 217.0 | —- | —- |
| Rawalakot | 211.2 | —- | —- |
| Jhelum | 205.3 | 263.2 | -57.9 |
| Muzaffarabad | 201.2 | 359.4 | -158.2 |
August 2011
| Station | Observed | Normal | Departure |
|---|---|---|---|
| Mithi | 530.0 | —- | —- |
| Kohat | 373.1 | 115.6 | 257.5 |
| Sialkot | 335.4 | 323.5 | 11.9 |
| Badin | 331.2 | 92.6 | 238.6 |
| Okara | 280.0 | —- | —- |
| Chhor | 276.0 | 69.4 | 206.6 |
| Nawabshah | 275.2 | 46.3 | 228.9 |
| Mir Pur Khas | 263.1 | —- | —- |
| Rawalakot | 257.0 | —- | —- |
| Kakul | 257.0 | 266.5 | -9.5 |
| Lahore (PBO) | 255.1 | 194.5 | 60.6 |
| Padidan | 251.2 | 40.5 | 210.7 |
| Noorpur thal | 219.1 | —- | —- |
| Murree | 216.2 | 335.5 | -119.3 |
Climate Data Processing Centre (CDPC)
Pakistan Meteorological Department, University Road, Karachi PAKISTAN