US warns of growing El Niño risks

The US National Oceanic and Atmospheric Administration (NOAA) said Latin America and the Caribbean (LAC) could be facing a far different scenario for weather-related events in the months ahead compared to 3Q17.

In its latest 2018 update, NOAA sees a higher chance of El Niño-related development in the coming months with a growing risk of floods and droughts in South America, while expecting the Caribbean to see fewer such events than normal.

The August update stands in stark contrast to 3Q17, which was marked by the multi-billion dollar impacts of Hurricanes Harvey, Irma and Maria and cool waters in the central Pacific (La Niña) giving relief to South America from the coastal El Niño-related disasters seen earlier that year.

NOAA has raised the likelihood of below-normal activity this season for Atlantic basin tropical cyclones to 60%. NOAA's Climate Prediction Center (CPC) also announced a more than 62% likelihood of El Niño formation during this year's hurricane season, growing to 71% by November-January.

NOAA said in its latest update that sea surface temperatures across the tropical Atlantic Ocean and Caribbean Sea have remained much cooler than average. A combination of stronger wind shear, drier air and increased stability of the atmosphere in the region where storms typically develop will further suppress hurricanes. Storm activity to-date and the most recent model predictions also contribute to the update.

For the entire season, which ends Nov. 30, NOAA predicts between nine and 13 storms (winds of 39mph or greater) of which four to seven will become hurricanes (winds of 74mph or greater), including two potential hurricanes (winds of 111mph or greater).

So far, the season has seen four named storms, including two hurricanes. An average six-month hurricane season produces 12 named storms, of which six become hurricanes, including three major hurricanes.

Back in May, when NOAA's CPC first forecasted activity levels for the 2018 Atlantic hurricane season, it had given a 25% chance of a below-average level of storms forming. At that time NOAA was calling for 10 to 16 named storms, five to nine hurricanes and one to four major hurricanes.

A composite forecast of various sources, compiled by reinsurance and ILS-related news site Artemis, continues to call for a total of 12 named storms, six hurricanes and two major hurricanes across the 2018 Atlantic season.

El Niño on tap

In its bi-monthly report, the CPC said it favors "the onset of El Nino in the coming months" with growing likelihood of El Niño to occur in late 2018-early 2019. El Niño is a major factor in NOAA's updated forecast, as it now sees a much greater chance of the climate phenomena developing with enough strength to suppress tropical storm development during the latter part of the season.

CPC noted that when El Niño occurs, with unusually high temperatures in equatorial Pacific Ocean waters, in the December-February period, this causes dry conditions in northern Brazil and the potential for warmth in southern Brazil, wet conditions in Argentina, Uruguay and Paraguay, as well as coastal flooding in Peru and Colombia.

South America experienced severe impacts related to El Niño during the southern summer of 2015-2016.

Pictured: Flooding in Peru caused by El Niño in March last year.

Preparedness urged

"Today's updated outlook is a reminder that we are entering the height of hurricane season and everyone needs to know their true vulnerabilities to storms and storm surge," said Brock Long, who is the administrator of the US Federal Emergency Management Agency (FEMA).

"Now is the time to know who issues evacuation orders in their community, heed the warnings, update your insurance and have a preparedness plan. Don't let down your guard, late season storms are always a possibility, always keep your plans updated," said Long.

"There are still more storms to come - the hurricane season is far from being over. We urge continued preparedness and vigilance," added Gerry Bell, lead seasonal hurricane forecaster at CPC.