Dale C. S. Destin |
The June to November 2016 (summer and autumn) climate outlooks are now available for Antigua and Barbuda. We are optimistic that some droughts will come to an end over this period. Meanwhile, uncomfortably warm temperatures are expected for the upcoming six months. June to November is also the Atlantic hurricane season; it is likely to be the most active since 2012.
May 2016 was wetter than last year’s; however, it was still a relatively dry May – the second driest in nine years. Hence, the droughts (meteorological, agricultural, hydrological and socioeconomic) continue across Antigua and Barbuda. We are now entering the 36th month of mostly moderate or worse rainfall deficits.
Looking forward – some droughts are likely to ease. At worst, slight meteorological and agricultural droughts will exist at the end of the March-August and December 2015-November 2016 periods. Meanwhile, a moderate drought or worse is possible at the end of the January-September 2016 period.
The warm phase of El Nino Southern Oscillation (ENSO) – El Nino, is expected to end in weeks and a transition to the cold phase of ENSO – La Nina, is expected during our wet season – July to December. This is good news for us in that La Nina, unlike El Nino, generally encourages rainfall across our area, mainly during the wet season. This is one of the main reasons why we are optimistic about the possibility of drought ending rainfall over the next six months, if not sooner.
However, there is some caution with our optimism as La Nina is not guaranteed nor are its normal positive impacts on our rainfall. Further, the strength of the La Nina is highly uncertain. A strong La Nina favours more rainfall, whereas a weak one favours less.
Precipitation and temperature
Over the coming three months – June to August (JJA), above to near normal rainfall is expected. This could result in the meteorological and agricultural droughts coming to an end or at worse be at slight levels at the end of the period. Unfortunately, these rains are unlikely to end the more serious hydrological and socioeconomic droughts; these will likely continue at moderate or worse levels.
September to November (SON) is also expected to have above to near normal rainfall. SON is on average our wettest “season”, accounting for nearly 40% of our yearly rainfall. Thus, if this forecast pans out, all droughts would be significantly eased, if not end. This is especially true if the JJA forecast holds true also.
So far, 2016 is about 70% wetter that last year, but it’s still much drier than normal. It is now almost certain that the dry season (January-June) will be drier than usual for the third consecutive year.
The summer heat is likely to be on, as warmer than usual temperatures are forecast for June to August. With high confidence of warmer than usual weather, there is also the potential for extreme temperatures. The heat could be very distressing for many especially since night-time temperatures are likely to be higher than usual. This has negative implications for health especially among older adults, infants and young children.
The hurricane season
Relative to the last three years, we are likely to have the most active Atlantic hurricane season since 2012. Notwithstanding, the forecast is for the season to fall in the near normal range with around 14 named storms, 7 becoming hurricanes and 4 major hurricanes.
Like our wet season, the great determinant of the hurricane season is ENSO. El Nino tends to suppress tropical cyclone (depression, tropical storm, hurricane) activity, while its sister-phenomenon – La Nina, does the opposite. Hence, the eventual activity of the season is largely dependent on the strength of La Nina which is quite uncertain, at this time. Stronger La Ninas tend to favour more active seasons than weaker ones.
For Antigua and Barbuda, the probability of a named storm (tropical storm or hurricane) affecting the islands during an active season is quite high (around 74%) and much higher than during a normal or quiet season, with around 59% and 26% probabilities respectively. Meanwhile, the probability of us being affected by a hurricane during an active season is around 49% as opposed to 18% in a normal one and 10% in a quiet one.
Irrespective the kind of Atlantic hurricane season that occurs, we need to be fully prepared, as it only takes one hurricane to set our life and community back by decades. Prepare for the worst and hope for the best!
The next set of outlooks will be available by July 3, 2016.