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Forecasting

with the installation of a new satellite dish at Bermuda Weather Service (BWS).The dish is tuned to a geo-stationary weather satellite with a sub-point on the equator.

with the installation of a new satellite dish at Bermuda Weather Service (BWS).

The dish is tuned to a geo-stationary weather satellite with a sub-point on the equator.

"With this new system, we can intercept the signal from the satellite directly,'' explained Roger Williams of BWS. "That enables us to get much higher resolution and updates every 15 minutes. Under the old system, the lower-resolution imagery could have been two hours old by the time we got it.'' The new hook-up provides not only the visible channel and the infra-red channel, but also the water vapour channel. By looping the three together, Mr.

Williams explained, much more accurate information can be obtained.

"We can track developing small storm systems and squall lines, which may only have a time frame of an hour before they hit. The new system is also really useful for following and tracking tropical storms.'' Mr. Williams said the new-found ability to calibrate the temperature of cloud-tops would enable the BWS to accurately pinpoint areas such as the eye of hurricanes and areas of severe convection. More accurately categorising hurricanes and detecting minor changes in their intensity will be another benefit.

Dr. William Gray, who forecasts hurricane activity, has forecast 11 named storms this year, against an average 9.7 such storms in a season. Dr. Gray's precise forecast was for 55 named storm days this year against an average 38.

One reason the new satellite dish would be helpful in tracking all this activity, Mr. Williams said, was because of a paucity of surface observations given Bermuda's isolated mid-Atlantic location.

"Predicting the likelihood and intensity of rainfall still tends to be a bit of problem,'' Mr. Williams said. "With this new dish, especially for tropical weather systems, we will be able to begin to quantify rainfall.'' An integrated workstation linked to the new system will be delivered in August. Other plans call for integrating radar imagery and putting summary information on the BWS Internet site, to which new graphics are also in the process of being added.

In related stories: The BWS is pursuing an initiative known as the "Slosh Model''. It covers not rainfall, but Sea, Lake and Overland Surges from Hurricanes.

"There has been a tacit agreement from the United States for a dialogue for them to develop a basin model of Bermuda based on a grid along the east coast of the United Sates,'' Mr. Williams said.

Data will be input to the Slosh Model to enable surge predictions to be made for any particular storm or scenario.

"Historically, we have not been able to predict storm surges, but now we could forecast, say, a ten-foot surge in St. George's and advise people accordingly,'' Mr. Williams said.

BWS meteorologist Jimmy James has had two photographs which he took of cloud formations prior to the arrival of Hurricane Lily last year accepted for publication in Weather , the international monthly journal of the Royal Meteorological Society.

One of Mr. James' photographs will grace the cover of the magazine, and another will be published inside.

Mr. James said he could not recall a Bermuda story featuring in the magazine before.

HURRICANES SUPPLEMENT HUR