The Nigerian Meteorological Agency (NiMET) has warned that the expected poor visibility across the country may cause flight cancellations and delays.
NiMET also cautioned against extreme dust weather conditions in some parts of the Northern states of Nigeria, just as it said that the Southern states should expect thunderstorms.
The regular weather forecast released to journalists by Professor Mansur Matazu, the Director-General, NiMET, said that the expected flight delays and cancellations are for the safety of air travellers.
According to NiMET, the expected extreme weather conditions would occur throughout the country from November 17 through 20, 2021.
NiMET pointed out that the significant visibility deterioration was expected on Saturday, November 20, in some northern cities such as Maiduguri, Kano, Katsina and Sokoto with visibility values ranging from 5,000-2,000m with isolated cases of visibility below 1000.
It said most parts of the central states are expected to be partly cloudy with sunny intervals, while the southern states are expected to be cloudy with prospects of isolated thunderstorms.
The statement hinted that dust is expected to be raised at Faya Largeau in the Chad Republic, a major dust source region for Nigeria and West Africa.
He emphasised that the Saharan high-pressure cell and its pressure belt across the Saharan deserts with centre value at 1021hPa on November 17, 2021, is expected to intensify further to about 1025hPa on 18th and 1027hPa on both 19th and 20th.
The statement added: “The tightening of its (Saharan) pressure gradient is expected to be strengthened on 18th and 19th. Stronger surface (10m) winds at the dust source (Saharan) regions is expected.
“Strong upper-air wind speed of about 40 – 45 knots, at the dust transport (925hPa) level, with the direction that favours dust dispersion from this source region to the northern parts of Nigeria.”
According to the statement, two major dust plumes are expected to be successively raised at Faya Lareau in the Chad Republic on November 18 and 19, adding that the dust is expected to progressively reduce the horizontal visibility values in the extreme northern parts of Nigeria from Friday, November 19, 2021, to less than 5000m.
Matazu, thereby, advised motorists to drive with caution especially in the extreme northern parts where reduction in visibility is envisaged.
The agency emphasised further that more attention is expected especially during the early morning period when horizontal visibility is mostly impaired.
It emphasised that hot and dry atmospheric conditions associated with harmattan could result in heat exhaustion and advised the people to keep the body hydrated by drinking water, saying that this is good to avoid “heat stroke.”
It noted that due to the dust weather, temperatures at night could be very low, and advised for wearing of adequate clothing.
The expected reduction in visibility may disrupt flight operations through cancellation and delay of flights; this is for the safety of air travellers.
The Agency, however, said that it would continue to monitor the weather and the public updated.