No End in Sight for Drought-Hit Antigua

22 06 2018

Dale C. S. Destin |

There is no end in sight for the current drought affecting Antigua. Not only there is no end in sight but it is expected to get worse, perhaps much worse.

Potworks Dam, a Billion Gallon Dam - Jun 5, 2018.

Potworks Dam, our billion gallon dam, is empty. Pic taken Jun 5, 2018, courtesy Karen Corbin – Humane Society.

Analyses done for the upcoming months, for as far as the (forecasting) eyes can see – through December 2018, suggest a moderate drought or worse will continue. For the drought to end, we need a very wet month or a few months of above normal rainfall – it’s possible but highly unlikely, based on projected climate signals.

LikelihoodOfRainfallForAntigua

The period with the highest likelihood of getting less than usual rainfall is July to September. It is near 100% certain that this period will be, at least, moderately dry i.e. rainfall in the bottom 20% of the historical record. This means that such dryness occurs no more than once every five years.

Already, June 1-20 is tied for the second driest across some parts of the island in over a generation. Further, the year, thus far, is the driest since 2015 and the second driest since 2003.

Meanwhile, the rainfall for the year has a 60% chance of being below normal. The projection is for the year to get around 965 mm (38 in) with a 70% likelihood of it being in the range 686 to 1295 mm (27 to 51 in).  On average, Antigua gets 1194 mm (47 in).

Rainfall For Anu 2018

Ongoing or potential impacts of the drought include the following:

  • Crop or pasture damage or losses
  • Decreased food production and crop scarcities
  • Financial losses primarily to farmers and related sectors
  • Water shortages and restrictions
  • Higher than usual grass and bush fires
  • Environmental degradations

The current and projected dry weather is largely due to the ongoing cooler than normal tropical North Atlantic, which is projected to remain this way through much of the rest of the year. The dryness could be intensified by El Nino, which is now likely to develop by October.

Recall that drought is not the absence of rainfall but rather lower than usual rainfall or a deficit in rainfall. Thus, relatively dry weather conditions will prevail for the drought period.

If you found this article informative, I would be very grateful if you would help it spread by emailing it to a friend, or sharing it on Twitter or Facebook.

Follow us for all you need to know about the current drought and all things weather and climate. Follow us on twitterfacebookinstagramtumblrflickrgoogle+, and youtube. Thank you!

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Updated Hurricane Season Forecast: Near Normal Season is Now Most Likely

12 06 2018

Dale C. S. Destin |

Good news: Our June updated forecast for the 2018 Atlantic Hurricane Season is now available and it indicates that the hurricane season will most likely be near normal. The prediction is for an accumulated cyclone energy (ACE) index of 93, 11 named storms, 5 becoming hurricanes and 2 becoming major hurricanes.

Jun2018HurrucaneSeasonForecast

This forecast is relatively good news for us because, during a near normal season, there is a 33% chance of a named storm (tropical storm or hurricane) affecting, i.e. passing within 120 miles of, Antigua and Barbuda. By comparison, during an active season, the chance soars to 75%. Further, we have never had a major hurricane during a near normal season.

Chance of Anu Being Affected By TS

These new numbers represent notable decrease below those of the previous forecast. Previously, the forecast called for an ACE of 119, 13 named storms, 6 hurricanes and 3 major hurricanes. Current and projected cooler than normal sea surface temperatures, across the tropical North Atlantic, are mainly responsible for the downward trend in this year’s forecast hurricane season activity.

Recall that the ACE is the overall predictor of a hurricane season, it is a measure that is based on the total number of storms, their intensities and durations.

A typical season has an ACE index of 106, 12 named storms, 6 hurricanes, and 3 major hurricanes. Major hurricanes have sustained wind speeds of at least 178 km/h or 111 miles per hour (e.g., Category 3 or higher), based on the Saffir Simpson Hurricane Wind Scale.

If this forecast pans out, 2018 would be the least active since 2015. Notwithstanding, a season with activity second only to 2017, since 2005, cannot be ruled out.

According to other forecasts surveyed, the latest consensus is for an ACE of 96, 12 named storms, 6 hurricanes and 3 major hurricanes. Thus, our forecast is calling for similar activity; however, regardless of the forecast, you should always prepare well each season, as it only takes one hurricane to ruin your year.

The Atlantic hurricane season started June 1 and will continue until November 30.

We will be updating this forecast by July 10.

If you found this article informative, I would be very grateful if you would help it spread by emailing it to a friend, or sharing it on Twitter or Facebook.

Follow us for all you need to know about the upcoming hurricane season and all things weather and climate. Follow us on twitterfacebookinstagramtumblrflickrgoogle+, and youtube. Thank you!





Usual Rainfall for April, Droughts Eased

31 05 2018

Dale C. S. Destin |

The rainfall for April 2018 was near normal; however, is the driest April since 2015. The island-average total for the month was 71.6 mm (2.82 in). This represents 84% of the usual amount of 85.6 mm (3.37 in).

Potworks_Apr282018

The last three month period – February to April, upon which the assessment of the current intensity of the drought is based, had 126.2 mm (4.97 in), 65% of the normal total of 193.0 mm (7.60 in). This puts the meteorological droughts current intensity at slight, improving from moderate. With Potworks Dam about to go totally dry and the vegetation of the Island struggling, there is little doubt that most other droughts are at moderate levels or worse. Happily, the full impacts of the droughts are being masked by the presence of the desalination plants.  According to the Antigua Public Utilities Authority, around 85% of all potable water is coming from the sea via reverse osmosis and is expected to climb to near 90% in days.

The seven-month period – October 2017 to April 2018, the duration of the drought thus far, was seriously dry. The total for the period of 407.92 mm (16.06 in) is the lowest since 2001 and the eighth lowest on record dating back to 1928.

RainfallDeficitGraphic_April2018

Based on the last set of rainfall outlooks, the news is not good for rainfall. Overall, below normal rainfall is most likely for, at least, the next three months – June to August. Additionally, the projected rainfall for 2018 is below normal with a 60% confidence. Thus, there is every reason to believe that the droughts will continue and likely worsen.

Even if the rainfall total turns out to be near average, it will not be enough, especially with respect to the hydrological drought, as the monthly evaporation rates significantly exceeds rainfall totals for most of the upcoming months. The chance of the droughts ending is around 20% or slight.

Recall that the current drought started in October 2017 with the intensity at serious levels. On average, serious meteorological droughts last for close to a year, but not continuously at serious intensity. We have just passed the seven-month mark. Will it go another five months? The answer still looks more like to be yes than no.

Keep following us for more on this developing story and all things weather and climate.

 





Updated Hurricane Season Prediction: Less Active Season Forecast

13 05 2018

Dale C. S. Destin |

Our updated forecast for the 2018 Atlantic Hurricane Season is now available. It calls for a less active season than previously indicated and a less active season than 2017.  The prediction is for an accumulated cyclone energy (ACE) index of 118, 13 named storms, 6 becoming hurricanes and 3 becoming major hurricanes.

May2018HurrucaneSeasonForecast

These new numbers represent a slight decrease below those of the previous forecast. Previously, the forecast called for an ACE of 135, 15 named storms, 7 hurricanes and 3 major hurricanes. Recall that the ACE is the overall predictor of a hurricane season, it is a measure that is based on the total number of storms, their intensity and duration.

A typical season has an ACE index of 106, 12 named storms, 6 hurricanes, and 3 major hurricanes. Major hurricanes have sustained wind speeds of at least 178 km/h or 111 miles per hour (e.g., Category 3 or higher), based on the Saffir Simpson Hurricane Wind Scale.

The 2017 Atlantic hurricane season was one of the most, if not the most destructive for the Caribbean. Several islands experienced, at least, catastrophic damage. Barbuda, an island which is a part of the state of Antigua and Barbuda was decimated and left uninhabitable for a while.

Ten of last year’s 17 named storms reached hurricane strength—meaning they had sustained winds of at least 119 km/h or 74 miles per hour, and six of the 10 hurricanes were major ones. It was the seventh worst year on record, based on the ACE index of 223.

If this forecast pans out, 2018 would be the least active since 2015. Notwithstanding, a season with activity second only to 2017, since 2005, cannot be ruled out.

According to other forecasts surveyed, the consensus is for an ACE of 109, 14 named storms, 7 hurricanes and 3 major hurricanes. Thus, our forecast is calling for similar activity; however, regardless of the forecast, you should always prepare well each season, as it only takes one hurricane to ruin your year.

The Atlantic hurricane season begins in less than three weeks—June 1 and concludes on November 30.

We will be updating the forecast by June 10.

If you found this article informative, I would be very grateful if you would help it spread by emailing it to a friend, or sharing it on Twitter or Facebook.

Follow us for all you need to know about the upcoming hurricane season and all things weather and climate. Follow us on twitterfacebookinstagramtumblrflickrgoogle+, and youtube. Thank you!

 





Very Dry March; Droughts Reintensify

26 04 2018

Dale C. S. Destin |

March 2018 was the driest since 2014 and the 12th driest March on record dating back to 1928. The island-average total for the month was 17.8 mm (0.70 in). This represents only 34% of the usual amount of 51.8 mm (2.04 in).

D&P_RainfallGraphic_Mar2018

Rainfall in inches for the past 24 months. Multiply by 25.4 to get mm.

The last three-month period – January to March, upon which the assessment of the current intensity of the drought is based, had 116.1 mm (4.57 in), only 66% of the normal total of 176.0 mm (6.93 in). This puts the meteorological droughts current intensity at moderate, down from slight.

DroughtGraphic: Slight_to_Moderate

With Potworks Dam about to go totally dry and the vegetation of the Island struggling, there is little doubt that other droughts are at moderate levels or worse. Thankfully, the full impacts of the droughts are being masked by the presence of the desalination plants.

Rainfall_Accu_Anu

Interestingly, in a negative way, the rainfall accumulation for the year, thus far, is not very dissimilar to that of 2015 and 1983 – the driest and second driest years on record, respectively. We make no conclusions here but it may be an ominous sign.

The six-month period – October 2017 to March 2018, the duration of the drought thus far, was seriously dry. The total for the period of 326.4 mm (12.85 in) is the fifth lowest on record dating back to 1928. It is also the lowest total for the given period since 2001. The rainfall deficit since the drought started is at 260.1 mm (10.24 in).

Based on the last set of rainfall outlooks, the news is not good for rainfall. Overall, below normal rainfall is most likely for the six-month period April to September. Thus, there is every reason to believe that the droughts will continue and likely worsen.

Even if the rainfall total turns out to be near average, it will not be enough, especially with respect to the hydrological drought, as the monthly evaporation rates significantly exceeds rainfall totals for most of the upcoming months. The chance of the droughts ending is slight – less than 30%.

Recall that the current drought started in October 2017 with the intensity at serious levels. On average, serious meteorological droughts, for Antigua, last for close to a year, but not continuously at serious intensity. We have just passed the six-month mark. Will it go another six months? The answer looks more likely to be yes rather than no.

Keep following us for more on this developing story and all things weather and climate. Follow us here on wordpress and also via twitterfacebookinstagramtumblrflickrgoogle+, and youtube.





Early Forecasts for 2018 Atlantic Hurricane Season

11 04 2018

Dale C. S. Destin|

Our early season forecast for the 2018 Atlantic Hurricane Season calls for above normal activity. The prediction is for an accumulated energy (ACE) index of 135, 15 named storms, 7 hurricanes and 4 major hurricanes.

Apr2018HurrucaneSeasonForecast

A typical season has 12 named storms, 6 hurricanes, and 3 major hurricanes. Major hurricanes have sustained wind speeds of at least 178 km/h or 111 miles per hour (e.g., Category 3 or higher), based on the Saffir Simpson Hurricane Wind Scale.

The 2017 Atlantic hurricane season was one of the most destructive for the Caribbean; several islands were almost totalled. Barbuda, one half of the twin island state of Antigua and Barbuda was left uninhabitable for a while. Ten of last year’s 17 named storms reached hurricane strength—meaning they had sustained winds of at least 119 km/h or 74 miles per hour—and six of the 10 hurricanes were major ones.

If this forecast pans out, 2018 would be the second most active since 2010; second to last year’s season.

The Atlantic hurricane season begins on June 1 and concludes on November 30.

We will be updating our 2018 forecast by June 10.

According to other forecasts surveyed, the consensus is for an ACE of 105, 14 named storms, 6 hurricanes and 3 major hurricanes. Thus, our forecast is generally calling for higher activity than most; however, regardless of the forecast, you should always prepare well each season, as it only takes one hurricane to ruin your year.

Follow us for all you need to know about the upcoming hurricane season and all things weather and climate. We can be followed on  twitterfacebookinstagramtumblrflickrgoogle+, and youtube.





2nd Wettest February In Years, Yet Less Than Usual Rainfall

1 04 2018

Dale C. S. Destin|

February 2018 was the second wettest since 2011, yet the rainfall total for the month was below the usual.  The island-average total was 35.8 mm (1.41 in); however, the usual amount for the month is 55.9 mm (2.20 in). Clearly, with only 64% of February’s rains falling, there was no positive impact on the drought situation being experienced.

Slight Meteorological Drought

Rainfall in inches for the past 24 months. Multiply by 25.4 to get mm. For records, the year given marks the start of the period.

The three-month period – December to February, upon which the assessment of the current intensity of the drought is based, had 198.6 mm (7.82 in). This puts the meteorological droughts at slight. However, with Potworks Dam about to go totally dry and the vegetation of the Island struggling, there is little doubt that other droughts are at moderate levels or worse. Of course, and thankfully, the full impact of the droughts is being masked by the presence of the desalination plants.

Drought Level is Slight

Based on the last set of rainfall outlooks, the news is not good for rainfall. Overall, below normal rainfall is most likely for the six-month period March to August. Thus, there is every reason to believe that the droughts will worsen. Even if the rainfall total turns out to be near average, it will not be enough, especially with respect to the hydrological drought, as the monthly evaporation rates significantly exceeds rainfall totals for most of the upcoming months. The chance of the droughts ending is slight – less than 30%.

Recall that the current drought started in October 2017 with the intensity at serious levels. On average, serious meteorological droughts last for close to a year, but not continuously at serious intensity. We have just passed the six-month mark in the drought. Will it go another six months? Unfortunately, the answer looks more like yes than no.

Keep following us for more on this developing story and things weather and climate. We are available on twitterfacebookinstagramtumblrflickrgoogle+, and youtube








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