El Nino may develop in May as PMD warns of heatwave in southern Pakistan

ISLAMABAD: Strong indications point to the possible development of the El Nino phenomenon in May, a shift that could intensify heat and alter weather patterns across Pakistan, according to meteorological projections cited by the Pakistan Meteorological Department (PMD).

The PMD has also issued a heatwave alert, warning that southern parts of the country may experience a low-intensity heatwave from April 29 to May 3. During that period, temperatures in some areas could climb to as high as 52°C.

As per details, El Nino is a climate phase linked to unusually warm sea surface temperatures in the Pacific Ocean, while La Nina refers to cooler-than-average waters. Both are part of the El Nino-Southern Oscillation (ENSO) system, which plays a major role in shaping weather conditions around the world.

According to the projections, the onset of El Nino could bring higher temperatures, weaker winds and below-normal rainfall in Pakistan. In more severe cases, it may also lead to drought-like conditions in some regions.

The PMD said ENSO and the Indian Ocean Dipole (IOD) are currently in a neutral phase. However, most global climate models show a 61% probability of El Nino developing between May and July.

Authorities said the situation is being monitored closely and that timely warnings would be issued if the threat of a severe heatwave increases.

Relief expected in upper areas

While southern parts of the country are expected to face rising temperatures, upper regions may see some respite due to two successive western weather systems. The first system is likely to affect northern areas from the night of April 27 through April 29, while the second is expected from May 3 to May 5.

These weather systems could lower temperatures in the affected areas by 2°C to 4°C.

Historical climate data shows that May and June are usually the hottest months in Pakistan. The areas considered most vulnerable to extreme heat include southern Punjab, upper Sindh and southeastern Balochistan, where average temperatures generally range between 43°C and 45°C.

Observational data further suggests that temperatures in these regions are already running 2°C to 4°C above normal.

PMD explains climate pattern

PMD spokesperson and Deputy Director Anjum Nazir Zaigham said El Nino and La Nina are two phases of the same climate system. He explained that during El Nino, waters in the central and eastern Pacific Ocean become significantly warmer than usual, which directly affects weather conditions in Pakistan.

According to Zaigham, this can lead to prolonged hot spells, weaker winds, reduced rainfall and, in some places, drought conditions. By contrast, La Nina is associated with cooler ocean temperatures and often brings stronger winds, more rainfall and relatively cooler conditions in Pakistan and other parts of South Asia.

Citing World Meteorological Organisation data, Zaigham said current sea surface temperatures are already 0.5°C above normal. He added that if the anomaly reaches 0.8°C, the likelihood of El Nino forming in May rises sharply to 61%.

With temperatures already trending above average and climate indicators moving in the same direction, the outlook suggests a hotter summer season may be taking shape across parts of the country.