NORTHERS - "Northers" are cold , wet, northeast air masses which are pushed to the south normally between November and February by large Arctic air masses. These "Northers" manifest themselves in Belize as colder-than-normal temperatures, wide spread heavy rains and choppy seas spawning light craft warnings. These northers are usually predictable both in forecast and in duration. Belizeans have adapted well to these disturbances and they usually only disrupt operations on the sea such as fishing and diving. The northers can make visiting the rainforest a pleasant experience as the cooler temperatures make hiking through the forest comfortable.
HURRICANES - The more dangerous disturbance are the non-frontal, low pressure, large scale storms called hurricanes. These storms are spawned over the eastern Atlantic from the warm tropical waters and develop a highly organized circulation. Hurricanes are classified as tropical depressions when wind speeds are less then 64 knots, and full blown hurricanes once they reach sustained winds of 64 knots.
June 1 is the official beginning of the Atlantic Ocean, Caribbean Sea and Gulf of Mexico hurricane season because conditions are just becoming ripe for tropical storms and hurricanes. But historically, most hurricanes occur between August and October in Belize.
Though only 5% of hurricanes recorded in the Atlantic reached Belize between 1886 and 1978, the country has a devastating history of encounters with these powerful storms. The 1931 hurricane nearly destroyed Belize City taking 1000 lives. Hurricane Janet destroyed Corozal Town in 1955. And in 1961, Hurricane Hattie struck Belize with winds of 300km/hr, killing 275 with its 13 foot tides.
How hurricanes form and the ingredients needed to form one are well known .Ocean water above 80 degrees F is needed for hurricanes to begin and keep up their strength. The major source of energy for hurricanes is the warm, humid air above the tropical Atlantic. As the air rises around the storm's center it cools. The cooling moisture condenses to form clouds and rain. Condensation releases heat and it is this released heat that powers hurricanes. If the layer of 80-degree water isn't at least 200 feet deep, a tropical storm could die before gaining hurricane strength. Storms stir up the ocean. If this stirring brings up cool water from the bottom, the storm will lose its power plant of warm surface water.
A hurricane begins in an area over a warm ocean where winds coming from different directions converge. As the winds come together the air is forced upwards. If the air is unstable, that is if it has a tendency to continue rising once given an upward shove, a storm can begin growing. To have the needed supply of moisture, the air up to about 18,000 feet above the ocean needs to be humid and somewhat stable as strong winds above can shear a storm apart. As this air is pulled into the storm it supplies even more energy.
The final ingredient needed for a disturbance to grow into a tropical storm and then a hurricane is an upper atmosphere high pressure area above the growing storm. The air in such high pressure areas is flowing outward. This helps push away the air that's rising in the storm, which encourages even more air to rise from the ground. A hurricane's winds are caused by air near the ocean rushing inward to replace air that's rising in the storm. The Earth's rotation gives the incoming air a counterclockwise spin in the Northern Hemisphere. Southern Hemisphere hurricanes spin clockwise. A hurricane grows weaker when it moves over cool water or over land, which cuts off the supply of warm, humid air, which is the storm's energy source.
If you would like to chart the progress of hurricanes during this season, we have provided a NOAA GIF-format hurricane tracking chart for you to download (hur_track.zip 51K). You can print out this chart and then map the coordinates of the hurricane as they are reported.
We've also provided a CURRENT FORECAST OF TROPICAL STORM FORMATION. PLEASE NOTE: This link will open a new window on your monitor with the most recent forecast. You can close this small window after reading it. Please note that if you are running on minimum memory, you may not want to create another window as it could freeze Netscape.
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