The Invasion of Loo winds – Karachi feels the heat!

Karachi like the southern as well as the central parts of the country is under a severe heat wave. The temperatures have rose rapidly in these parts following a late winter rainy wave that brought down the temperatures early this month.

Loo winds invade Karachi

Loo wind may sound like a disease but infact its not a name of any illness. These winds could be fatal to infants and elderly people, exposure to it often leads to heatstrokes which are common in interior Sindh during this time of the year. These winds normally blow during the afternoon, at this time they are the strongest. These winds blow heater-like winds that gives an unpleasant feeling. Loo is famous all over Pakistan and north-western India, it is basically a Punjabi word. These winds are a Pre-monsoon activity which occur frequently in May and June

These winds originate from the desert regions of Pakistan and India which includes Cholistan, Thar, Thal and deserts of Balochistan. Low humidity and sizzling temperatures are the characteristics of these winds.

Heat wave of April – Record came close to be broken?

Heat waves are common during the month of April in southern Pakistan however this year was an exception. The highest monthly rainfall of 52 mm was recorded in 1935, it normally does not rain in Karachi during this month but on April 19, 5 mm rainfall with 60 km/h fresh winds occurred in the city.

The highest all-time temperature during April was 44.4 °C, which was recorded on 16 April 1947.

Timeline of the heat wave

The current heat wave had started from April 26 as forecasted by Pakistan Weather Portal (PWP) on April 24 and gained intensity on April 29. It is affecting the southern parts of the country and few adjoining central areas. Following is the day to day event in Karachi;

April 29

Karachi experienced one of its hottest day of the year when the mercury touched 41°C. The humidity dropped to just 9% during the rush hours.  The sky was clear with no cloud formation near the coastal areas of the city. The increase in temperature occurred due to change in the direction of the winds that was blowing from the northerly/north-westerly direction since the morning. The hot winds reached 35 km/h during the mid-day though after a slight change in the wind pattern during the evening the temperature did however manage to drop but not significantly, mercury dropped to just  30°C during the night.

• Record broken?: No, the highest temperature of April 29 is 42°C in 2002.

April 30

The city kept on sweating as the mercury remained constant at 40°C, a 1°C decrease occurred since yesterday. Overall the situation was identical to April 29, the winds were blowing from northerly direction. The wind speed was somewhat higher as it reached 41 km/h during the afternoon. The humidity further dropped to just 4%.

• Record broken?: Yes, the highest temperature of April 30 was 36°C in 1999.

Heat wave of May – Record to be broken? – Updated on May 4

May is the most hottest month in the metropolis. The highest temperature ever recorded in Karachi was on May 9, 1938, when temperatures reached 48.8 °C (119. Rainfall is very rare, the highest monthly rain that occurred was in May 1933, when 33 mm rain was recorded in the city.

The current heat wave 2012 that started from April 26, is continuing as of May 4.

May 1 – Labour Day Heat

During the morning till late afternoon, northerly/north-westerly hot winds continued to blow in the city. The temperature reached 42 °C, the new hottest day of the year in the city.

• Record broken?: Yes, the highest temperature of May 1 was 38°C in 1995.

May 2 – Death Anniversary of Osama Bin Laden

After experiencing the hottest day of the year, Karachi relatively remained cool at 35°C as cool south-westerly winds made their return in the city.

• Record broken?: No, the highest temperature of May 2 was 37°C in 2004.

May 3 – World Press Freedom Day

Northerly winds once again returned to the city as temperature rised to 40°C.

• Record broken?: Yes, the highest temperature of May 3 was 36°C in 2001.

May 4

Karachi experienced another hottest day of the year (last one on May 1) when mercury rised to 42°C. Winds during the morning were stable blowing from Northerly direction.

• Record broken?: Yes, the highest temperature of May 4 was 37°C in 2001.

When will this heat wave move die out?

During this whole week, temperatures are likely to remain on the higher side that is 40°C – 42°C. PWP first thought that the temperature would decrease from May 4 but now due to the latest developments, temperature in Karachi would decrease after May 5, a decrease in temperature would occur as mercury would drop from 40°C by 1°C to 3°C and from May 7, normal conditions would prevail over the city.

The heat wave in Sindh and adjoining South Punjab is likely to persist till 4 to 5 days excluding Karachi. Temperature could shoot-off to 44 – 45°C in some cities of upper Sindh. Since this is a severe heat wave, precautions are required especially to the people belonging to the southern parts during the next few days.