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Weather
WEATHER
Since weather and climate play such a significant part in human activity, providing timely and accurate
weather warnings and forecasts is one of the most important functions of every national meteorological
service (NMS). This function also gets the most attention from decision makers and the public. Indeed,
because of the significant improvement in safety and protection of property through timely and accurate
weather information, Government, like its counterparts worldwide, views national weather service outputs
as a public service and continues to finance and support them.
National Weather Service
Weather information provided on a daily basis meets a
broad spectrum of local and national needs such as:
• Early warning for natural disaster mitigation (for the
Cayman Islands: hurricanes, thunderstorms, floodproducing rain, etc.)
• Information on changes in weather to help the public
in planning daily personal and social activities
• Advice for sustaining and improving environmental
quality
• Day-to-day and seasonal and climate forecasts and
other products in support of weather-sensitive
economic sectors
All user groups rely heavily on this broad range of
services to make sound decisions concerning public safety
and cost efficiency.
Government policy makers, international agencies
and other individuals use products and services from
national weather services in support of such areas as
agriculture, recreation and tourism, construction, water
resource management, etc.
Administration and Equipment
The Cayman Islands National Weather Service, under the
administration of the Civil Aviation Authority, is
responsible for the monitoring of meteorological events
and provision of meteorological information. A good
example of this would be the “cooperative upper air
station” that provides critical information to the National
Hurricane Center in Miami, Florida, for hurricane
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forecasting and tracking.
Surface and upper air weather observations from the
service are sent to the regional meteorological centre in
Washington, DC. From the centre, these observations are
transmitted into a worldwide network for use by other
meteorological as well as non- meteorological concerns.
The data is also available for use in numerical weather
prediction models for use in the production of mediumand long-term regional and global weather and climate
forecasts, as well as for global aeronautical planning by
the aviation community.
Cayman’s service operation includes an upper-air
station, surface weather observations, climate data
processing, analysis and storage, as well as public and
aviation forecasting. The service now has at its disposal
one of the most advanced international satellite
communication systems (ISCS) for the purpose of
receiving and disseminating weather observations to the
regional centre in Washington, and on to the rest of the
world.
The ISCS system also receives weather charts and
alphanumeric information along with data from
numerical weather prediction models (NWP). The NWP
data enables the development of regular and specialized
weather charts and forecasts through 120 hours or five
days. Another valuable piece of equipment is a highresolution satellite system that continuously receives and
displays visible, infrared and water vapor satellite
pictures, at resolutions from one to four kilometres. This
Weather
11 July and 2.89 inches of rainfall was recorded.
Even though the hurricane season was fairly
uneventful, the Cayman Islands did experience some
severe weather events in 2003. Heavy rain caused major
flooding on 19 January and 27 June in Grand Cayman. The
very high rainfall total in January was particularly unusual
and included the highest 24-hr total since records
commenced in 1957. This single 24-hour total on January
18th also exceeded any previous January total on record.
Flooding in both cases was localized to southwestern
Grand Cayman.
satellite system is an extremely valuable tool in monitoring
the development of weather systems.
Staffing and Training
The staff consists of two fully trained junior technicians,
five trained senior technicians and four trained weather
forecasters. Routine hourly surface weather observations
are taken at the Owen Roberts International Airport for 17
hours daily (6 a.m. through 10 p.m.) with 24-hour service
envisaged for the future.
Rapid advances in information and communication
technology today have led to continuous improvement
and refinement in weather forecasting and observing. As
a result, continued professional development training of
staff is required to stay abreast of the latest technological
developments, operational techniques and research.
During 2003, one officer completed his mid-level
technician course in climatology and hydrology at the
Caribbean Institute of Meteorology and Hydrology in
Barbados. A second officer completed the senior technician
weather forecasting course at the Institute in late October.
Additionally, two officers were hired by the Civil
Aviation Authority to work at the Gerrard Smith
International Airport in Cayman Brac with dual
responsibilities of weather observers and air traffic
assistants. These officers were sent to Grand Cayman in
early March to take a two-month course in weather
observations. A third officer was added later in the year
with all three officers scheduled to take an entry-level
technician course at CIMH in Barbados February 2004.
This training will provide these personnel with the skills
to make quality hourly surface observations during
operational hours (7 a.m. through 7 p.m.) at the Gerrard
Smith airport, thus fulfilling international requirements.
Weather Statistics
The average annual temperature was 28.4 deg. C/83.2
deg. F. The highest monthly average temperature recorded
was 29.9 deg. C/85.9 deg. F during the month of August,
with the lowest monthly average of 25.3 deg. C/77.6 deg.
F occurring in January.
The highest recorded temperature occurred on 11
August and was 34.4 deg. C/94.0 deg. F. The lowest was
20.0 deg. C/68.0 deg. F on 10 January.
The warmest day was 11 August with an average of
30.0 deg. C/86.0 deg. F. The coolest day was 20 December,
with an average of 24.0 deg. C/75.3 deg. F.
Rainfall totalled 1844.6 mm/72.62 ins., which is 16.21
inches higher than the 30-year normal of 56.41 inches. The
wettest month was June with 392.4 mm/15.45 inches
recorded. The driest month was April with 4.3 mm/ 0.17
of an inch recorded. The most rainfall in a 24-hr period was
240.1 mm/9.45 ins., on 18 January.
There were 187 days free of rainfall and 178 days on
which rainfall was recorded. There were 62 days on which
thunder occurred.
The average barometric pressure was 29.96inches/
1014.6millibars. The highest pressure was 1023.1millibars/
30.21inches recorded on 21 December. The lowest pressure,
1004.8millibars/29.67inches, occurred on 18 March.
The average wind was from the East at 10 knots with
April, June and July being the windiest months with
average wind speeds of 12 knots.
Annual average humidity was 77%, with the highest
monthly average of 79% recorded in February, July and
October, and the lowest of 75% in April, May and December.
The most humid day was 1 September with a very muggy
95%, while 29 December with 58% was the lowest.
There were 18 clear days, 249 partly cloudy days and
98 cloudy days.
2003 Weather
Hurricane Season
2003 had an active season with 14 named storms; seven
became hurricanes with three evolving into major
hurricanes with wind speeds of 110mph or greater. The
long-term average is 10 named storms, six becoming
hurricanes, three major — Category 3 and higher or wind
speeds greater than 110 mph. Despite the active season
only one storm, Tropical Storm Claudette, moved through
the northwest Caribbean. Claudette passed 160 miles
southwest of Grand Cayman on 10 July. The storm
produced cloudy skies, fresh winds and rough seas on 10-
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Weather
The staff of the National Weather Service, back row, from
left: Mr. John Tibbetts (Chief Meteorological Officer),
Mrs. Sharon Ebanks, Mr. Avalon Porter, Mrs. Charlene
Bodden, Mr. Allan Ebanks and Mr. Gilbert Miller. Front
row, from left: Messers Limardo Scott, Winston Gall,
Kerry Powery and Floyd Webb. Missing from the photo
is Head of Meteorological Services Fred Sambula.
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