Category Archives: Tropical Cyclones

A large circulation sproducing heavy rainfall, very strong winds and storm surges

Hurricane Matthew nears Western Haiti 4 and 5 October 2016

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Hurricane Matthew threatening Florida

Hurricane Matthew continues it's slow movement north towards the western portions of Haiti. The storm is moving at 9 km/h northwards as a powerful Category 4 storm sustaining winds of 120 knots at the core with higher gusts to 140 knots (Approximately 220 km/h with higher gusts to 260 km/h).
cimssmodelformatthewThis is the most powerful storm since Hurricane Felix in 2007 and news reports already confirm 3 fatalities at the present time. Further fatalities cannot be ruled out especially across Haiti.forecastcone




Path of Hurricane Matthew

Path of Hurricane Matthew

According to the National Meteorological Centre of Haiti, the Hurricane Matthew has a central pressure of 943 hPa. Hurricane winds are occurring within 45 km of the centre and storm force wind extend outwards to 315 km from the eye.

Western Haiti affected by Hurricane Matthew

The CIMSS forecast models suggests that the eye of Matthew would pass over the far western fringe of the country placing the towns / cities of Jeremie and Les Cayes at significant risk. Other smaller towns at risk include Dame Marie, Port A Piment and Tiburon

Haiti is an impoverished country and such a storm would have a significant impact and cause major disruption to the country.

Very heavy rainfall, storm surges and landslides are being forecast given the strength of the storm. The outer rain bands are starting to impact the southern coastal fringe of the country.

The western part of Haiti does not contain too many substantial towns or cities as shown on the “Urban Extents Map” but as shown on the population density map, the western side of the country is moderately to densely populated implying the region includes numerous small villages, farms, farming communities and rural towns. In this regard, the storm will have a major impact to the country.

The storm will also have a significant impact to eastern Cuba due to the number of large towns or cities within the region.

Forecasts are being made for rainfall to reach as much as 1,000 mm in isolated locations of Haiti which would cause landslides and serious flooding.

Forecast models suggests the storm emerging into the Bahamas within two days and traversing towards or close to Florida and possible impact within the Carolina's of the United States in six days. Major uncertainty exists beyond three days but it is clear that the whole south eastern sea board of the United States including the states of Florida, Georgia, South Carolina and North Carolina is now under threat from the storm. There is a possibility of landfall in eastern North Carolina in six days but this is to early to tell at the present time.


1 - CIMSS - Forecast model for Hurricane Matthew acquired 4/10/2016.
2 - National Meteorological Centre Haiti.
3 - National Weather Service (USA).
4 - NASA Worldview - Population plots for Cuba, Haiti and Jamaica.

Typhoon Chaba nears Taiwan October 3 to 5 2016

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The North west Pacific Ocean is clearly a region that favours powerful tropical storms. Barely days after Typhoon Megi made landfall across eastern Taiwan, another powerful typhoon has developed close to Taiwan. This time the storm is not forecast to make landfall on Taiwan.

Typhoon Chaba is travelling north but located approximately 500 km east of Taiwan as another powerful Category 4 storm on the Saffir Simpson Scale. The storm is sustaining winds of approximately 125 knots (Approximately 231 km/h) with higher wind gusts to 150 knots (Approximately 278 km/h) at the core. A well defined eye features on satellite photos with deep convection visible. Satellite photos also suggests an intense and compact storm.

The storm is forecast to reach peak intensity as a powerful Category 4 storm with peak wind gusts of 135 knots (Approximately 250 km/h) with higher gusts of 165 knots (305 km/h) and hence the storm could approach a Category 5 system at peak intensity as it moves north towards the Ryukyu Islands then towards southern Japan.

However, the storm is forecast to weaken once it starts to encounter more shear, cooler waters and land masses of Japan.

Sea surface temperatures of the region are around 29C to 30C but temperatures drop further north.

Forecast models suggests a weakening storm making landfall across Japan in coming days.

This shows how vulnerable the region is to such powerful storms. This is the forth typhoon that has reached Category 4 on the Saffir Simpson Scale within the past 30 days across the region.


CIMSS - Forecast plot for Typhoon Chaba dated 3 October 2016.
NASA Worldview – Satellite photo of Typhoon Chaba acquired 3/10/2016.

Hurricane Matthew Carribean Sea – October 1 to 5 2016

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A small but intense tropical storm just to the north of Columbia (South America) within the Carribean Sea transitioned from a Category 1 hurricane into a Category 5 hurricane rapidly. The transition appears to have taken place within a span of 12 hours. The storm has since weakened to a Category 4 storm.

Meteorologists are stunned as this storm developed from almost nothing to a Category 5 hurricane within a time period of 36 hours.

The storm briefly reached Category 5 on the Saffir Simpson Scale with peak winds at the core approaching 146 knots (Approximately 270 km/h). The storm is currently sustaining winds of approximately 130 knots (Approximately 241 km/h) close to the core. It is still a significant storm and a potentially dangerous storm for Haiti, eastern Jamaica and Cuba.

The storm initially tracked west but is now turning northwards and threatening Haiti, Jamaica and Cuba. The storm is currently located at 13.2 degrees north and 73.3 degrees west and expected to maintain its course as suggested by the CIMSS model.

The storm is expected to weaken as it encounters landmasses but once it reaches the Bahamas, the storm is forecast to regain some strength as a Category 3 storm. There is significant uncertainly at the present time as to whether the storm will impact Florida or traverse along the eastern seaboard of the United States and remain off the coast.

Given its strength, it is one storm being watched by NOAA and Hurricane Hunter aircraft are being flown into the storm to allow meteorologists to monitor its progress.

There appears to be an eye wall replacement cycle occurring or trying to occur but satellite photos clearly shows a tiny eye surrounded by deep convection.

Given the strength of the storm, this has potential to be a significant and damaging event especially for Haiti. Forecasts are being made for rainfall of 400 to 625 mm over southern and western Haiti.

A forecast of 250 mm to 500 mm of rain is being made for eastern Jamaica.

Such rainfall would be life threatening with flooding and mudslides suggested.

This is one storm given its behaviour that will receive much media attention across the region over coming days due to its strength.


1 - CIMSS - Forecast track of Hurricane Matthew acquired 2/10/2016.
2 - CIRA - False colour of Hurricane Matthew acquired 2/10/2016..
3 - National Hurricane Centre.
4 - NASA Worldview (TERRA) satellite photo of Hurricane Matthew dated 1/10/2016.