Predicting Weather By The Moon - Xavier University Libraries

OTHER WEATHER CONDITIONS
NAME
DEW
FOG
.
FROST
SNOW
HAIL
WHEN LIKELY
Full Moon
Waning Gibbous
Last Quarter
New Moon,
1st Q to
Waxing Gibbous.
Full Moon to 3 rd Q
At night; New Moon
to Waxing Gibb..
In day, Waxing Cresc.
to Last Q., including 1 st Q.,
Waxing Gibb., Full M. and
Waning Gibb.
187
HOW FORMS
Temperature of the ground
drops to cause condensation of the
air immediately above it. Need still,
clear night. Must be high humidity
in the air next to the ground, low
humidity in the air just above it.
Absence of cloud allows ground
to cool enough for moist air just
above it to condense. In the desert,
dew is often the main water source
for plants and animals.
As for dew, but deeper layer
of moist air is required. It is possible
to have dew without fog but
not fog without dew. Fog is low
cloud and forms mainly at night.
On clear nights, when conditions
allow for fast cooling to
below freezing. (Slow cooling only
results in dew.)
Freezes in atmosphere before
it falls. Ice crystals bond in cloud
and then fall through cold air. Sign
of high winds, blizzards, or avalanches.
Rapid freezing, drops and
melts and freezes again as it encounters
warmer and colder air.