Predicting Weather By The Moon - Xavier University Libraries

Weather By The Moon
Reading Weather
maps
Most newspapers display daily weather maps, distributed
by the local meteorological service. The maps are
accurate and describe the current situation; and are generated
from an internation radar and satellite hook-up. Teams
of media weather-forecasters employ 3 or 4 different computerized
models from at least half a dozen satellite agencies.
Because some satellite readouts are taken from different
vantage points and times of the day, they often appear
contradictory. In such cases forecasters arbitrarily
decide which one to utilize. If the weather forecast in the
morning says it will be a fine day and by lunchtime there is
a downpour, then they picked the wrong model. The maps
don’t lie - it is only the interpretation of them that may be
off. There is a tendency to describe the weather as fickle,
if it does not match what was forecasted. But the weather
knows what it is doing. Perhaps in such cases it is the forecasters
who are fickle.
WHAT ARE ISOBARS?
We are all familiar with the black contours or whorls
on every weather map. They signify lines of equal pressure.
Presuure is the total weight of air, or vertical mass
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