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.

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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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