"Red sky at night, sailors delight. Red
sky in morning, sailors take warning."
A reddish sunset means that the air is dusty and dry. Since weather in
North American latitudes usually moves from west to east, a red sky at
sunset means dry weather—good for sailing—is moving east. Conversely, a
reddish sunrise means that dry air from the west has already passed over
us on their way east, clearing the way for a storm to move in.
"If a circle forms ‘round the moon,‘Twill rain soon."
or "If there’s a halo around the sun or moon, expect rain quite soon."
The circle that forms around the sun or moon
is called a halo. Halos are formed by the light from the sun or moon
refracting (bending) as they pass through the ice crystals that form
high-level cirrus and cirrostratus clouds. These clouds do not produce
rain or snow, but they often precede an advancing low pressure system
which may bring bad weather.
"If smoke hovers low near the ground it is likely to rain."
Smoke particles tend to absorb moisture from the air. The more moisture
present in the air, the more a particle of smoke will absorb, and the
heavier it gets. Heavy, moisture-laden smoke particles do not disperse
as easily as the lighter, dry ones do.
"When sounds travel far and wide, A stormy day will betide."
Sound travels at different speeds through different substances. It
travels faster through a solid substance than it does through air, for
instance. Sound travels better in air that is heavily laden with
moisture than it does in dry air.
"If birds fly low, Expect rain and a blow."
When the air pressure is high, it is easier for birds to fly at a higher
altitude. If the air pressure is low, indicating bad weather, birds
can’t fly as high because the air is less dense.
"Trace in the sky the painter’s brush,
The winds around you soon will rush."
The "painter’s brush" are cirrus clouds. These are high-level ice clouds
that often precede the approach of a storm system.
"Mares’ tails and mackerel scales
Make lofty ships carry low sails."
Mares’ tails are cirrus clouds, called this
because they sometimes resemble the flowing tail of a horse in the wind.
Mackerel scales are altocumulus clouds. They appear broken and scaly.
Neither of these cloud types will bring rain or snow themselves. They
do, however, precede an approaching storm front by a day or two.
"Pale moon rains; Red moon blows."
White moon neither rains or snows." The more dust particles there are in
the air, the greater the chance that moisture will have something on
which to form raindrops. Drops of rain cannot form unless they can form
around a "condensation nucleus," which is a dust particle, ice crystal,
or some similar tiny object suspended in the air. When moonlight passes
through air laden with dust particles, it appears pale or reddish. When
the air is very clear, it appears white.
"If clouds move against the wind, rain will follow."
Clouds that are moving in a direction that differs from the way the wind
is blowing indicates a condition known as wind shear. This sometimes
indicates the arrival of a cold front. Weather fronts usually bring
rain.
"You can tell the temperature by counting a cricket's chirps."
Crickets are accurate thermometers;
they chirp faster when warm and slower when cold. They are extremely
accurate. Count their chirps faster for fourteen seconds, then add
forty, and you have the temperature (in Fahrenheit) of wherever the
cricket is.
"Flies – Flies bite more before a rain."
This rule does not always apply, but insects do calling more during
moist weather, as flying is more difficult. Heat causes human sweating,
which makes you a more appetizing target. Theses two reasons, plus a
release of more body odors when atmospheric pressure on your body
lowers, will add up to the rule that flies and insects are more
bothersome just before a rain than at any other time.
"The higher the clouds, the better the weather".
Higher clouds indicate both dryness of air and higher atmospheric
pressure. Both these qualities are present with fair weather.
"Rainbow in the morning gives you fair
warning. A rainbow afternoon, good weather coming soon."
As weather moves mostly from west to east, if the sun raises in the
east, with a rainbow and its showers in the west, then rain will soon be
on its way. Whereas if a rainbow is seen in the afternoon/evening and
the wind is still blowing westerly then the weather should break soon,
as there are enough breaks in the cloud for the sun to shine through,
and fair weather will follow.
"Sharper the blast, sooner 'tis past."
Cold fronts bring bad, squally and sometimes violent weather, but pass
through quickly.
"When the dew is on the grass, Rain will never come to pass. When grass
is dry at morning light, Look for rain before the night."
Dew forms when grass gets colder than the dew-point temperature (the
temp at which dew forms). At night, grass cools when heat from the
ground radiates upward. In a clear, dry atmosphere, this heat escapes
the atmosphere and rises into outer space. In a moist and humid
atmosphere, water vapor absorbs some of that heat and can redirect it
back down to the ground, warming up the grass, and thus keeping it dew
free. Dew on the grass is therefore a sign of a high pressure system,
and good weather.
"When clouds appear like rocks and towers,
the Earth's refreshed with frequent showers."
This proverb references the foreboding visual characteristics of storm
clouds — known as cumulonimbus clouds. These towering behemoths reach up
to 75,000 feet in the sky, and before turning anvil-like, they appear as
rocks being stacked upon each other. So when rocks and towers appear in
the sky, expect storms.
"When the glass falls low, prepare for a
blow; when the glass is high, let your kites fly."
This is a simple proverb about watching and reading barometric pressure.
In the early days of this weather gauge, it was called a “glass”
(because a glass tube housed the mercury). When the “glass” is low —
that is, when the mercury is low, meaning low pressure — you can expect
rain and generally poor weather. When the mercury is high, a high
pressure system is in (or coming in), and fair weather can be enjoyed.
"When leaves
turn their back ‘tis a sign it’s going to rain."
Some trees, such as oak and maple, have leaves that will curl when the
humidity is very high and the wind is blowing strongly. Both these
conditions indicate an approaching storm.
"I know ladies by the score
Whose hair foretells the storm; Long before it begins to pour
Their curls take a drooping form."
Human hair, especially blond hair, has a tendency expand in length as
the humidity rises. This may cause naturally-curly hair to droop. Or it
may cause straight hair to curl up a little. The higher the humidity,
the more likely it is to rain.
"If birds fly low expect rain and a blow."
When the air pressure is high, it is easier for birds to fly at a higher
altitude. If the air pressure is low, indicating bad weather, birds
can't fly as high because the air is less dense.
"Pale moon rains; red moon blows. White moon
neither rains or snows."
The more dust particles there are in the air, the greater the chance
that moisture will have something on which to form raindrops. Drops of
rain cannot form unless they can form around a "condensation nucleus,"
which is a dust particle, ice crystal, or some similar tiny object
suspended in the air. When moonlight passes through air laden with dust
particles, it appears pale or reddish. When the air is very clear, it
appears white.
"Seagull, seagull, sit on the sand; It’s
never good weather when you’re on land."
If there’s one bird that will know when a storm is approaching
over the ocean, surely it’s the seagull. Seagulls spend the majority of
their time flying over the ocean or sitting on its surface, so if you
see them lingering on land it’s a sure sign there’s ill weather at sea.
One reason why they do this is they can sense changes in barometric
pressure—and hurricanes have the lowest pressure of any kind of storm.
Another explanation for why gulls land and wait for storms to pass is
because the incoming low pressure also discourages thermals (the rising
currents of warm air that allow birds to effortlessly soar to higher
altitudes).
"When the wind is in the north, the skillful
fisher goes not forth.
When the wind is in the east, ’tis good for neither man nor beast.
When the wind is in the south, it blows the flies in the fish’s mouth.
When the wind is in the west, there is it the very best."
