Hurricane Irma Got Relegated

17 03 2018

Dale C. S. Destin |

Hurricane Irma was relegated from being tied for the second strongest Atlantic hurricane, in terms of wind speed, to being tied for being the third strongest. This is according to the final report on the system issued last week by the U.S. National Hurricane Center (USNHC). The USNHC, in its post-mortem report, lowered Irma’s maximum sustained winds from 185 mph to 180 mph.


VIIRS Satellite Image of  Hurricane Irma When it was at its Peak Intensity and Made Landfall on Barbuda at 0535 UTC (1:35 am) 6 September, 2017.

The downgrade of Irma, by 5 knots (5.75 mph), is relatively negligible; however, from the record book standpoint, it is notable. And looking at the raw data, the USNHC may have still been generous with the peak winds of 180 mph – it could have been lowered further.

There are some other notable things gleamed from the report that I would like to share. A report I would recommend persons to read.

Recall that many persons blamed Irma on climate change, something that I and others continue to debunk? It turned out that Irma’s strength had very little to do with warm sea surface temperatures – the link that is being made to climate change, and more to do with low wind shear and available atmospheric moisture, according to the USNHC report – not climate change.

USNHC has confirmed what we already recognized – Irma was a very small hurricane. Her hurricane force winds extended only 24 km (15 miles) from the centre. On average, the hurricane force winds from a hurricane extends out 64 km (40 miles). Her small size saved Antigua from similar type destruction to what occurred in 1995 from Hurricane Luis.

Along parts of the track of Irma, the effect of the winds on the sea was reminiscent of a tsunami. For example, in Puerto Piloto, the sea retreated offshore by up to 12 metres (39 feet) due to the force of the southerly winds on the eastern side of Irma’s circulation. No doubt similar would have happened for parts of Barbuda and elsewhere.

Irma's Storm-Surge as Recroded by Our Station at River Road, Codrington, Barbuda

Irma’s Storm-Surge as Recorded by Our Tide Station at River Road, Codrington, Barbuda

For Barbuda, the was a tsunami-like surge of 2.5 metres (9.3 feet) measured by our tide gauge at River Road, Codrington, which is on the southern side of the island. It is likely that the surge generated by on the north side was higher. These surges inundated significant portions of Codrington and the island as a whole, which is very flat. At least half of the island lies within 25 feet of mean sea level. The Codrington Lagoon remains breached from the massive surges and waves created by Irma.

In addition to the tsunami-like surge, there were monster waves as high as 8 metres (26 feet) caused by Irma. Such large waves on top of the high surge would have caused seawater to inundate areas well inland, causing serious erosion and saltwater intrusion into aquifers and agricultural lands.

Also confirmed was the fact that the ECMWF was by far the best performing model with respect to the track forecast. However, all the models were left wanting with respect to the forecast of intensity.

In weeks we will have the first set of forecast for the upcoming hurricane season, stay tuned for those.

Don’t forget to take our weather survey, which will help us to better communicate the weather to you: Weather Survey.

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Windmageddon To Produce Swellmageddon Across The Caribbean

3 03 2018

Dale C. S. Destin |

A gigantic low-pressure system, nicknamed windmageddon due to widespread damage and power outages it caused across the Northeast United States, is about to cause swellmageddon. Swellmageddon because the low-pressure area will cause enormous, dangerous and destructive sea swells that will wreak havoc on the shorelines of Antigua and much of the Caribbean.

High Surfs

Large Breaking Swells (High Surfs)

Large and dangerous battering swells, peaking in excess of 4 m (13 ft), are expected to pommel our shoreline starting Sunday and continuing until Friday. This is expected to be the worse swell event thus far for the winter season.


Such high swells will produce even higher surfs that will result in beach closures as swimming conditions will become extremely dangerous for beachgoers.

Swellmageddon will likely cause major beach erosion; flooding of low lying coastal roads; disruptions to marine recreation and businesses; financial losses and damage to coral reefs.

This major swell event may also cause disruptions to potable water from desalination as turbulent seas could increase the turbidity of the water above safe levels for the desalting plants.

A high surf warning is expected to be issued by the Met Office for Antigua and the rest of the northeast Caribbean. Other Offices are expected to issue warnings for as far west as the Bahamas and extending south to the Windward islands. Swells could exceed 5 m (17 ft) across the Bahamas.

The impact on shorelines will not be the same everywhere. Depending on the depth and the natural shelter of the coastal waters the impact will be different. Shallow north-facing shorelines are expected to see the highest swells and surfs.

In open waters, the swells from swellmageddon will be virtually harmless to small craft operators as they will be long-period waves with gentle gradients.

Windmageddon will not cause any destructive winds across us, far from, but it will cause them to come from some very unusual directions for this part of the world. They are going to becoming from the south, west and north at times over the next several days before return the usual direction of east next weekend.

Keep following us for more on the weathermageddons and for everything weather and climate.

Drought Eased A Bit For Antigua

2 03 2018

Dale C. S. Destin |

Near normal rainfall for January has eased the drought across Antigua from serious to moderate levels. The island-average rainfall for January was 62.5 mm (2.46 in), 91% of the usual total.

The three-month period – November to January, upon which the assessment of the intensity of the drought is based, had 211.6 mm (8.33 in). It is the second driest such period since 2000 and the 13th driest on record dating back to 1928.

Based on the last set of rainfall outlooks, the news is not good for rainfall. Below to near normal rainfall is expected for the period March to May. Thus, there is every reason to believe that the droughts will worsen or remain the same. There is only a slight chance of them ending over the above mentioned period.

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.

While we can only speak definitively to meteorological droughts, there is little doubt that we are also experiencing agricultural, hydrological and perhaps socioeconomical droughts. These are likely to become more noticeable in the incoming months; however, the full impact will continue to be masked by the presence of desalination plants.

Potworks Dam Feb 13, 2018, Courtesy Karen Corbin - Humane Society

Potworks Dam Feb 13, 2018, Courtesy Karen Corbin – Humane Society

Potworks Dam, the country’s largest catchment with a capacity of around a billion gallons of water, continues to show signs of drying up. Around the middle of February, the water level had fallen to about a quarter or less. It could be totally dry in couple months.

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


February to July 2018 Climate Outlooks for Antigua and Barbuda

8 02 2018

Dale C. S. Destin |

Antigua and Barbuda is back in a meteorological drought again. The latest round of climate outlooks suggest that it is unlikely to worsen and could even end in a few months. However, with us entering the heart of the dry season, the prospects of real relief are not good. Beyond the next few months, it is very unclear as to how the rainfall will perform. Meanwhile, temperatures will vary over the upcoming six months.

Rainfall and drought

At least, a meteorological (Met) drought has returned to Antigua and Barbuda as of October 2017. The rainfall totals for our two wettest months – October and November, were below and well below normal respectively. Combined, it is the driest October-November period since 1983 – 34 year ago or in a generation.


Looking forward – the Met drought is likely to remain the same or perhaps come to an end in the next three months or so. Rainfall totals for December and January were near normal and the outlooks for February-April is for above to near normal rainfall.

Although the Met drought may not get any worse, we could still slip into a hydrological drought, if we are not already in one. Catchments are on the decline, as is normal for the dry season, and will unlikely be recharged by the rainfall of the upcoming three months.

Beyond April, rainfall performance is quite uncertain – the signals are all over the place. Hopefully, in a month’s time things will become relatively clear.

The cold phase of El Nino Southern Oscillation (ENSO) – La Nina is evident although an episode cannot yet be declared. La Nina is weak and expected to come to an end around April; hence, having very little impact on rainfall across our area.

If you are in our part of the world – the Caribbean, a moderate or strong La Nina is almost always welcome, particularly in the summer when it has a usual positive impact on rainfall. The opposite – El Nino, has a negative impact. Outside the wet season – July to December, ENSO has little or no effect on our rainfall.


Temperatures were generally near normal for the October-December (OND) period. However, the mean minimum temperature was above normal – the second highest since 2002, based on preliminary data.

The warmer than normal mean minimum temperature for OND was due mainly November and December having above normal nighttime low temperatures. This was reflected in the mean maximum temperature, where November and December also experienced warmer than normal daytime high temperatures.

Looking down the road – there is equal chance of the mean and maximum temperatures for the next three months – February to April, being below, near or above normal. However, the minimum temperature is likely to be above to near normal.

For the period May-July, the mean temperature is expected to be above to near normal. There is equal chance of the maximum and minimum being below, near or above normal.

See the following links for the full outlooks: CariCOF Newsletter – summary and outlooks for the region; precipitation outlooks and temperature outlooks.


Drought Again For Antigua

27 01 2018

Dale C. S. Destin |

None_to_Serious_DroughtAntigua is back in drought again. There are several types of drought and as of three months ending December 2017, rainfall figures indicate that Antigua has slipped into, at least, a meteorological drought.

The drought started October 2017, when less than 40% of the normal total rainfall fell for the month. It was the second driest October since 2000 and the 13th driest on record dating back to 1928. Normally, October is the wettest month of the year – averaging 161.0 mm (6.34 in); however, this year, only 61.2 mm (2.41 in) fell.

November did not fare any better with respect to rainfall, actually, it was worse. November only got around 32% of its normal rainfall. It was the driest November since 1997 – two decades ago.

Normally, November is the second wettest month of the year, averaging (5.97 in) – only (1.95 in) fell last November. Instead of being the second wettest, it was the second driest month of 2017 and the seventh driest November on record dating back to 1928.

December had near normal rainfall – far from enough to have much of a positive effect on the drought. By the end of the three-month period ending December – the rainfall deficit for the said interval was around 49% or (8.00 in). It is the sixth driest October-December period on record. At this deficit, the meteorological drought is deemed to be at serious levels.


There is no firm end in sight for the current drought – the chance of it ending over the upcoming three months is moderate, at best. It is more likely to remain the same or get worse.

On average, serious meteorological droughts last around 11 months. The chance of a serious drought ending in a hurry i.e. in less than six months is less than 20%.

Already there are signs of catchment drying up. Potworks Dam, the country’s largest catchment, by far, is well below half. In the past, such a drought would be more impactful socioeconomically; however, with the advent of at least two major desalination plants in the past three years, much of the impacts are being masked.

Potworks Dam Jan 16, 2018, Courtesy Karen Corbin

Potworks Dam Jan 16, 2018, Courtesy Karen Corbin – Humane Society

The last meteorological drought – the worse ever on record, came to an end September 2016. The meteorological drought also degenerated into agricultural, hydrological, socioeconomical and ecological droughts, which were quite costly to the economy of Antigua and Barbuda.

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



Snow in the Sahara Desert – Unbelievable But True!

11 01 2018

Dale C. S. Destin |


A few days ago, snow fell over parts of the Sahara Desert. To many this was unbelievable, especially in this era of fake news and alternative truth. However, it really snowed in the Sahara Desert, and not for the first time. Precipitation (rain, snow, hail, etc.) in deserts are rare but certainly not unheard of.

Algeria - dark green

Location of Algeria – dark green


Snow covered dumes in the Sahara Desert. Photo by Geoff

Snow in the Sahara Desert near the town of Ain Sefra, Algeria – 07 Jan 2018. Photo by Geoff Robinson 

It is understandable the disbelieve one would have about the news of snow taking place in the Sahara Desert. After all, it is “only” the hottest desert in the world – consisting of some of the hottest places on Earth. The mean temperature is around 29 °C (84 °F) but can reach as high as 50 °C (122 °F).

What is not well-known is the fact that very cold temperatures do occur in the Sahara Desert. Temperatures, particularly during winter can fall below freezing (below 0 °C or below 32 °F). So, temperatures do become conducive for snow in the Sahara, at times. However, temperature is not sufficient for snow – moisture is needed.

Contrary to popular belief, precipitation does take place in deserts, including the Sahara. Not a lot takes place but they do get precipitation. There is no universal definition for a desert but a good working one is an area receiving less than 250 mm (10 in) of rainfall annually.

In the case of the Sahara, the annual rainfall is less than 100 mm (3.9 in). It rains from December to March and in August. The rains in August are said to be characterized by thunderstorms, which can produce flash floods. And of course, snow falls at times during the winter months, as was the case a few days ago.

It snowed in the same location last year; however, before then it had not snowed in 2012 and 1979 -nearly 40 years ago.

Sahara snow event of 2012 as reported by Algerian TV channel, Central TV

Weird precipitation events are rare for deserts but they do occur:

In January 2013, a NASA satellite observed the Taklimakan Desert, in western China, covered with snow. The Taklimakan Desert temperature range from – 20 to 38 °C (68 °F to 100 °F) and the annual average rainfall is less than 40 mm (1.60 in).

In August 2011, Stephane Guisard of the European Southern Observatory photographed snow in the Atacama Desert. The annual average rainfall is around 1 mm (0.04 in).

A dusting of snow in the Atacama Desert

A dusting of snow in the Atacama Desert. Photograph was taken by Stéphane Guisard on 1 August 2011. 

In March 2015, Flash floods took place in the Atacama Desert – the driest desert in the world and one of the driest places on Earth. The annual average rainfall is around 1 mm (0.04 in). The floods caused two deaths and left 24 persons missing.

Precipitation may be rare for the deserts of the world but far from unprecedented. No only do they get light precipitation but also solid, on occasions.


Windy Weather to Cause More Hazardous Seas and Economic Losses

8 01 2018

Dale C. S. Destin |

Hazardous seas being caused by frequently strong winds – gusting to near gale force at times, will continue to keep most mariners in or near port over the upcoming week – causing further significant economic losses for many.

Seas around Antigua and Barbuda have been rough for most of the year, so far, and are set to remain that way or even worsen over the next seven days, at least. As usual, this type of weather is very disruptive to marine activities and have a negative economic impact, particularly on fisherfolk, those alone the fisheries value-chain and those involve in offshore pleasure cruises and adventures.

Small craft warning remains in effect for hazardous seas around Antigua and Barbuda and will likely remain in place for the rest of the week. Hence, small craft operators, especially inexperienced ones, should avoid navigating in these conditions.

Warnings are also in effect for beach-goers as high surfs are affecting beaches, producing beach erosion and dangerous swimming conditions. Beach-goers should avoid the waters, especially those on the northern and eastern side of the islands. These high surfs are likely to subside to more manageable levels by Tuesday.

High surfs can also cause strong rip currents, which can carry even the strongest swimmers out to sea, and seawater splashing onto low-lying coastal roads, causing damage. Further, high surfs can also knock spectators off exposed rocks and jetties. Breaking waves may also occasionally impact harbours making navigating the harbour channel dangerous.

The wind speed will range between 14 and 22 knots (16 to 25 mph) and at times gusting to near 30 knots (35 mph). The winds will be strongest on Tuesday and Friday and will blow from near east for most of the week.

Wind speed – valid at 6 am, Tue, Jan 9, 2018

Seas will remain hazardous with steep waves ranging between 2 and 3 metres (7 and 10 ft), occasionally reaching near 4 metres (13 ft), mainly in open waters on the eastern or windward side of the islands.

Significant wave height (ft) – valid at 6 am, Tue, Jan 9, 2018

These strong winds not only cause hazardous seas but also cause certain onshore activities to be uncomfortable, if not dangerous. Hence, certain outdoor work will be hampered, if not halted, at times; thus, reducing productivity in other sectors.

The windy conditions and hazardous seas will also be experienced by all the islands of the Eastern Caribbean along with Hispaniola and the Bahamas, particularly the Atlantic coastal waters or the eastern and northern coastal waters.

The strong winds are not due to any storm system but rather because of steep pressure gradients across the area. Recall that winds blow due to pressure differences or pressure gradients, and the greater the gradients the stronger the winds and vice versa.

Also, the strength and position of the ever-present subtropical/Atlantic high-pressure system modulate the steepness of the pressure gradient. The closer and or stronger the subtropical high, the steeper the gradient, the stronger the winds and vice versa.

The subtropical high-pressure system will be stronger than normal for much of the next week; hence, the forecast continuation of strong winds, hazardous seas, disrupted marine activities and economic losses.

Although windy, the weather will be mostly dry with only occasional brief showers likely.

Follow us for all you need to know about this windy weather and all things weather and climate. We can be followed on twitterfacebookinstagramtumblrflickrgoogle+, and youtube.


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