October 2016 to March 2017 Climate Outlooks for Antigua and Barbuda

24 10 2016

Dale C. S. Destin |

The October 2016 to March 2017 climate outlooks are now available for Antigua and Barbuda. Our worst meteorological (Met) drought on record has come to an end; however, other droughts continue. It is unclear what will happen with respect to rainfall over the next six months as there are equal chances of below, near or above normal rainfall for October-December and January-March. Meanwhile, warmer than normal night-time temperatures are likely to continue.

Potworks Dam, Aug242016 (L) v. Sep62016 (R)

Potworks Dam, Aug 24 2016 (L) v. Sep 6 2016 (R). Pictures courtesy Karen Corbin – Humane Society. 

Drought

After over three years, the rainfall for September 2016 has brought the Met and agrometeorological (AgMet) droughts to an end. However, it was not enough to end the hydrological (Hydro) and socioeconomic (SE) droughts, which continue at slight levels or worse. The island-average of 213.4 mm (8.40 in) for September 2016 is the most for a September since 1995. Further, it is the wettest of any month since October 2012.

Drought Meter

Looking forward – below to near normal rainfall is likely for October-March. Meanwhile, there are equal chances of below, near or above normal rainfall for both October-December (OND) and January-March (JFM). Given these and other forecasts, there is a moderate chance of the country going back into Met and AgMet droughts, and the Hydro and SE droughts re-intensifying in the medium to long-term. Drought watches are in effect.

Rainfall Projection for Jul-Dec2016

El Nino Southern Oscillation (ENSO) – El Nino, is happily becoming a distant memory. There is now a 65% chance of a cold phase i.e. La Nina developing over the next three months.

If you are in our part of the world – the Caribbean, a La Nina would be more than welcome. Unlike El Nino, La Nina often brings us more than usual rainfall. Given our severe water crisis of the past three years, a La Nina is being prayed for.

Precipitation and temperature

Year-to-date, the rainfall for Antigua is 1.3 times more than all the rainfall for 2015. Further, it is the wettest January-September since 2013. Notwithstanding, we are still over an inch in the “red” relative to the long-term average of 792.5 mm (31.2 in).

The recent up-tick in rainfall seems to have flattened-out. There is no clear signal as to rainfall for the upcoming seasons: OND, JFM and October-March. The best forecast is trending toward near to below normal rainfall for the next six months.

The projected rainfall for 2016 is 757.3 to 1336.8 mm (29.8 to 52.6 in) or near to below normal. This is at least 182.0 mm (7.0 in) more than last year’s total. There is only a slight chance of above normal rainfall for the year.

For the period October to March, above normal temperature is likely. Further, night-time lows are likely to continue above normal through OND resulting in continued uncomfortable warmer than usual nights.  Relatively cooler nights are likely for JFM.

The hurricane season

The 2016 hurricane season will go down as the first active season since 2012. Thus far, the current Atlantic hurricane season has produced 14 named storms, 6 hurricanes and 3 major hurricanes.

The accumulated energy (ACE) index which matters most, has shot up to 119% of the average of 106 in less than a month from less than 50%. More than half of this ACE is due to the strength and duration of Major Hurricanes Matthew and Nicole.

In terms of numbers, the forecast for the season is on point as it called for around 15 named storms, 7 becoming hurricanes and 3 major hurricanes.

Notwithstanding the end of the season drawing near, we have been seriously impacted by tropical cyclones in November, recall Hurricane Lenny of 1999. Thus, we need to remain fully prepared, as it only takes one hurricane to set our life and community back by decades. Be prudent: stay prepared for the worst and hope for the best!

See the following links for the full outlooks: October 2016, October-December 2016, January 2016-March 2017October 2016-March 2017Drought, 2016 Updated Hurricane Season Forecast.

The next set of outlooks will be available by November 5, 2016.

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September 2016 to February 2017 Climate Outlooks for Antigua and Barbuda

29 09 2016

Dale C. S. Destin |

The September 2016 to February 2017 climate outlooks are now available for Antigua and Barbuda. Over the long-term (September-February), above to near normal rainfall is expected. However, in the short-term – September to November (SON), below to near normal rainfall is expected. The droughts are more likely than not to remain as is or end over the short-term. Meanwhile, uncomfortably warm temperatures are expected for the upcoming six months, especially during the short-term.

Drought

August 2016 is the wettest since 2011 and the wettest of any month since November 2014. It was a wetter than normal August with an island-average of 130.3 mm (5.13 in). Notwithstanding, it was not wet enough to end the droughts, which have gone past 38 months.

Looking forward – there is a moderate chance (55%) of the droughts either not getting worse or ending during the period SON. Conversely, there is also a moderate chance of the SON period having below normal rainfall. Notwithstanding, over the long run, above to near normal rainfall is expected. Thus, drought watches are in effect instead of warnings.

jun-nov2016_rainfall

The warm phase of El Nino Southern Oscillation (ENSO) – El Nino, came to an end in May. At which time, the chance of a cold phase i.e. La Nina was in excess of 75%. However, as of this month, the probability of La Nina is at 55% and declining.

If you are in our part of the world – the Caribbean, a La Nina would be more than welcome. Unlike El Nino, La Nina often brings us more than usual rainfall. Hence, given our severe water crisis of the past three years, to not have a La Nina as “promised” would be a great disappointment.

The rains over the past weeks have put a huge dent into the droughts. We are experiencing one of our wettest, if not wettest September in over 20 years. There is optimism that a few of the droughts have ended. More will be said on this, after a full assessment, by the middle of October.

Precipitation and temperature

Year-to-date, Antigua, on average, has had more than twice the amount of rainfall than for the same period last year. Notwithstanding, we are still over three inches in the “red” relative to the long-term average for January-August of 647.7 mm (25.50 in).

This up-tick in rainfall has a reasonable chance of continuing over the long-term: September 2016 to February 2017, there is an 80% probability of above to near normal rainfall. However, the projected rainfall for 2016 is 657 to 1218.5 mm (25.9-48.0 in) or below to near normal.

For the seasons SON (autumn) and DJF (winter), there are equal chances of below, near or above normal mean temperatures. However, over the long-term, mean temperatures are likely to be above normal. Higher than usual night-time low temperatures are likely to continue through November, resulting in continued uncomfortable warmer nights.

The hurricane season

We are passed the peak days of the hurricane season for us and for the season overall. However, we are still very much in the most active period of the hurricane season – August to October. Thus far, the 2016 Atlantic hurricane season has produced, 12 named storms, four hurricanes and one major hurricane.

The 12 named storms are 50% more than the average of 8 to date [September 25]. However, the accumulated energy (ACE) index which matters most, is less than 50% of the average of 106. The relatively low ACE is indicative of the fact that the storms have been generally weak.

The forecast is for a near normal season with around 15 named storms, 7 becoming hurricanes and 3 major hurricanes; this includes those already formed.

Notwithstanding the forecast, we need to be fully prepared, as it only takes one hurricane to set our life and community back by decades. Be prudent: prepare for the worst and hope for the best!

See the following links for the full outlooks: September 2016, September-November 2016, December 2016-February 2017September 2016-February 2017Drought, 2016 Updated Hurricane Season Forecast.

The next set of outlooks will be available by October 5, 2016.





Our May Newsletter is now Available

19 05 2015

Dale C. S. Destin |

We’d like to present you with our May newsletter. In this newsletter, you’ll find highlights of recent weather and climate news. Additionally, there are outlooks for the upcoming six months. Links are also provided for further information. Please read and feel free to share you feedback.

Newsletter_Pic

 

Follow us also on @anumetservice, facebook and tumblr for the latest on the current drought and other weather & climate news.








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