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The Basics
Study the picture above to get a good idea of some permanent systems on earth.
There are two zones between the land and the top of the atmosphere.
- Troposphere - This is in the lower portion and the depth varies
with the seasons , latitude and weather. There is a five mile depth at the poles to
ten miles high at the equator. This is the only place where our weather is.
Air here contains water vapor, dust, salt, and smoke. Without these dust particles
we would have no rain as they are the nuclei of all raindrops. Vertical movement of
air here is referred to as "currents" where the horizontal movement of air is called
"wind".
- Tropopause - This is the imaginary line that divides the Troposphere and
the stratosphere.
- Stratosphere - Tempeture's here remain fairly consistent at -67 F . This is the upper
portion of our atmosphere. There is no vertical movement of wind here only horizontal.
The wind speed here can reach several hundred miles an hour.
The Effect Of The Sun On Our Weather
The light waves from the sun are short wavelength. Many that approach our atmosphere
are reflected or refracted (bent) away from the earth by our atmosphere. Many do however,
pass through our atmosphere and hit the surface of the earth. When they do this they
loose little of their heat to the air because air cannot easily absorb the short
waves. The rays not absorbed by the earth are reflected a wavelength much greater
than those of incoming rays. The reflected rays are easily absorbed by our atmosphere.
This means that our air is then heated , expands and then rises. Cold air at higher levels
comes down , is heated and rises again.
The closer the sun's rays are to 90 degrees when they strike the earth the greater their
heating effect. Also, the longer the rays shine on the earth as in summer
the more earth heats up.
Wind
The surface of the earth is not uniform, heating is therefore, not uniform and we
get differences in pressure. One example of this is that land heats and cools
faster than water. In the summer we have large low pressure areas over continents
and high pressure areas over the oceans. In winter the reverse is true.
The air in the high pressure system tends to move towards the low pressure system.
The result is what we refer to as "wind". The greater the difference in pressure
(also, referred to as the "pressure gradient")the stronger the wind.
If that same air moves over the surface of the water the winds are stronger than
over land because there is less friction because there is no resistance created
by objects such as buildings and trees.
In a nut shell the sun rays are bent back by our atmosphere at a greater
wavelength consequently air is heated , expands and rises and cold air at
higher levels sinks.
If the world did not turn or had a uniform surface predicting the flow of
air would be easy to predict. It is because the earth turns that
the heating of the air is not uniform.
Wind
Air is a gas. When it is heated it expands (becomes less dense, lighter) and
rises. When it is cooled it contracts becomes heavier and sinks.
Air is usually heated by
the earths surface , when air rises the surface air
around it rushes in to fill the gap. This is the circulation that results in the
horizontal and vertical movement or air or "wind".
Pressure Belts
Our world is such that high and low pressure regions tend to form into "bands or
belts" that more or less encircle the earth.
Winds blow both northerly and southerly directions fro the highs toward the
adjacent lows but not directly North or South. The earths rotation causes the winds
to be deflected. The winds in the Northern Hemisphere are deflected to the right
and those in the Southern Hemisphere are deflected to the left.
The pressure belts in the picture above are not nearly as stable as the
picture may indicate. They follow the sun North and South with the season . They
are not particularly stable as far as latitude is concerned either.
Coriolis Effect
This deflection is known as the "Coriolis Effect". Another way of describing this
is to say air moving from high to low
pressure is deflected to the left. The deflection is the Coriolis force.
Warm air passing over a large body of water picks up a lot of moisture and
gives it up again when the air is cooled. This cooling may be accomplished
by the air rising , passing over a cold area, or running into a
a bank of cold air.
Land heats and cools faster than water.
Sea Breeze
Land tends to heat up more quickly than water areas during the day. The warm air
rises and the cooler air from the water rushes in to fill the gap.
Land Breeze
This is the exact opposite of the sea breeze. At night the land air
cools more quickly than the air over the water. This causes the cooler
air to rush toward the warmer air that is rising.
Northeast Trade Winds
In the northern hemisphere the north flowing air at hight altitudes is bent
eastward which builds up an area of high pressure which then forces the air
to sink toward the equator.
Atmospheric Pressure
This is the weight of the air. This is usually designated in two
categories, Highs and Lows.
Movement Of High Pressure
Highs are large area's that can stretch for hundreds of miles. Winds
are usually weaker in High than in a low pressure system. Highs are formed
in the northern polar regions. They move initially southward , than they meet
the prevailing westerlies and are carried south eastward, then eastward and
then northeastward. All things are not equal on earth so the areas in which
Highs form change from summer and winter.
Squall Line
Squalls are a line of thunderstorms ahead of a cold front. There can be more
than one squall line in a front if the front is made up of very unstable
air masses. Squall lines produce very strong winds. The strong wind ahead
of the front is NOT a gust. A gust is wind that flocculates up to ten knots
on off. A gust can last for days. A squall is the sudden increase in wind where
the variation is fifteen knots and remains above 20 knots for more than a minute.
The sudden burst of air and increase in wind speed just before the front passes
over you is referred to as a squall not a gust.
The approach of the cold front makes the barometric pressure drop.
Fronts
Air masses move at varying rates of speed. Sometimes one air mass will meet or
overtake another mass that is warmer or colder. This is called a front. If a cold
air mass under runs and displace a warm air mass the front is called a
Cold Air Front. Cold fronts tend to move quickly 25 to 30 mph's.
If a warm air mass over rides and displaces a cold air mass, it is called a
Warm Front. In a Warm Front the barometer will fall but not
as quickly as the approach of a cold front. It occurs on the
East side of a low. Warm front usually produces better weather. The warm
air of a warm front can not push through cooler air so it rides up over it. Usually,
a cold front coming later will displace or overtake the warm front. When a warm front
passes the barometer will rise and temperatures will rise.
In the Summer Large Low Pressure over contents and the Highs are over
continents.
Winter it is the reverse.
Highs tend to move toward lows the result is wind. The greater the pressure
between the tow the stronger the wind.
Wind over water is always stronger as it meets no resistance.
When air masses that move at varying speeds sometimes one will overtake another
this is called a "Front". Every front is a low pressure area.
Below are the various types of fronts:
Cold Front:
 
Warm Front
 
Sometimes, a cold front will overtake a warm front as opposed to under running
a warm front this is called an occluded front (occlusion). There are two types
of occlusion.
On a fax it is usually represented by a solid line with alternating triangles
and circles pointing the direction the front is moving.
Rain and weather can occur up to 300 miles in front of a warm front. Normally,
weather clears right after a front passes.
-
Warm Type Occlusion - If the overtaking cold front is warmer than the cold portion of
the warm front it is called a warm type occlusion.
- Cold Type Occlusion - if the overtaking front is colder than the other this is called
a cold type occlusion.
Front usually bring fog or precipitation, Precipitation in the form of rain, snow and or drizzle is
common as much as 290 plus miles ahead of a warm front. Normally, the weather
will clear shortly after a warm front passes. The weather in front of a cold
front is usually only in front of it on the order of a few miles. However, a
band of bad weather several miles wide usually also follows a cold front. So, you
will have bad weather just before and just after a cold front.
There is also a stationary front which is exactly what its name suggest, stationary.
This would mean that the bad weather can stick around for days.
Weather in cold fronts usually occur only a few miles in front of the front.
Remember that EVERY front is a low pressure system. Air circulates around
a High and Low pressure areas. In the Northern Hemisphere the circulation is clockwise
around a high and counter clockwise around a low.
In the Southern Hemisphere the reverse is true.
Below is a table of the clouds. These are broken down into their known
catagory of high clouds, middle level clouds and low clouds. Clouds are
made up of water vapor. In 1929 an international conference was held
in Copenhagen and cloud classification was standardized. There are ten cloud types
each of which may have several variations.
All high-level clouds are white in color due to
the fact that at such extreme altitudes they are
made up only of ice crystals, as the water vapour
from which they are initially formed has frozen.
Isobars
These are lines of pressure.
Thunderstorms
There are several things that must be present in order for a thunderstorm
to form. One of those is strong upward air currents or lifting. This can
be caused by a cold front under running a warm front. The air must have
a large concentration of moisture or water vapor.
Often the cooler air brought to the earths surface by down drafts can
act as a upward air current again to produce the next thunderstorm. Thunder
storms generally last only an hour however, subsequent ones are formed so
quickly that it makes it appear that the one lasted a lot longer.
The cumulus cloud then forms from the air rushing in from around the area.
The cumulus cloud grows taller and becomes a cumulonimbus cloud. The rain drops
and ice particles become to heavy and fall to the earth. This falling produces
down drafts and cut off the inflow of air. This stops the growth process of the
storm. When the rain drops have fallen the air clears and the strom is over.
The cirrus clouds often are shaped like an anvil. The leaning direction of the
anvil will often tell us in which direction the storm is moving. The cumulus cloud
must grow taller in order to push the perception into the higher altitudes so that
the anvil of a cirrus can form. Cirrus clouds are made up of ice crystals NOT rain
drops. A roll cloud is formed at the edge of the cirrus cloud. This is due to
violent air currents along the leading edge. If you were to look at the leading
edge of the cirrus the roll cloud would look a little bit like a swirling cloud, placed
at the base and in front. The dark area of the thunderstorm. This dark area extends from
the base of the cloud to the earth. This dark area has a core which is usually
the strongest part of the thunderstorm. When the roll cloud passes overhead
you could experience violent shifting winds with strong down drafts. These winds
can reach sixty knots or more. Micro burst are a little different in that
they can reach speeds of 120 knots.
Micro bursts
This is a column of sinking air that spreads out in all directions when it
hits the surface. These straight line winds can be at 30 to 40 knots or as
high as 120 knots. They often appear in groups meaning that after the first
one passes it can be followed by several others. A Macro burst is essentially
the same thing as a micro burst only larger. A macro burst can cover an area
several miles.
Lightning And Thunder
A cumulonimbus cloud occurs and then a build up positive and negative electrical
charges occur within this vertically developing cloud. These charges occur between
the earth and the base of the cloud. When the charges become big enough we see
a lightning flash. Lightninging is often refereed to as either cloud to cloud
lightning or cloud to ground lightning. Actually, lightning is a series of
flashes or strikes back and forth within tenths of a second. A flash to the surface
is usually started by a faint leader followed by another flash from the
ground to the cloud. Lightning charges can reach up to thirty thousand volts.
Because lightning releases a large amount of heat energy in a short time it
causes the sound waves we call thunder. This release of energy comes from
the atmosphere around the lightning strike collapsing.
High Clouds - Have a mean lower low level of 20,000 feet.
Cirrus (Ci) - Thin Feather like clouds mainly composed of ice
crystals. They appear as white bands or wisps. Often these wispy
cirrus clouds are an indication that a cold front will be in the
area within 24 hours . They can also indicate the direction of
which a storm may lie. A way to remember this is if you look
at the clouds they will look like paint brush strokes. "The Gods
have painted arrow lines from which direction the cold storm will come."
Before and after sunset , cirrus clouds may still be slightly yellow or red
being high altitude clouds , they light up before lower clouds and fade out
much later.
Sometimes these are referred to as "Mares Tails".
-
Cirrocumulus - A White patch or sheet or layer of cloud,. This appears as ripples.
These clouds are small enough that they would not ob secure the
sun or the moon. This is sometimes known as the "Mackerel Sky".
They appear as rippled sand. One way to remember this is "Mackerel
from red tide lay on the rippled sand."
- Cirrostratus (Cs) - Very thin, whitish high sheet like cloud. This
cloud gives rise to halos. This is how you determine the milky veil of
fog or thin stratus and alto status from cirrostratus.
Cirrostratus nearly always causes the sun or moon to produce this halo effect.
A good way to remember this is "All Halo the God Cirrostratus". This can
indicate precipitation within 24 hours.
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Middle Clouds - These lie between 20,000 feet and 6500 feet. These
are water droplet clouds. There are only 2 cloud types in the Middle
range and they both begin with Alto.
Alto cumulus (Ac) - These clouds resemble the wool on the back
of sheep. These balls of wool are usually arranged in groups. They can
be white or gray. These take the form of a sheet, or layer of puffy wool.
Precipitation is likely within 10 to 20 hours, usually
proceeds a cold front.
Alto stratus (As) - Uniform sheet cloud. Gray or Bluish, uniform
appearence, totally or partly covering the sky. It can at times ob secure the
sun or moon completely. Sometimes they can be seen encircled by a corona
( A set of one or more rainbow colored rings surrounding the sun, moon, or
other source of light). Precipitation is likely within 10 to 20 hours. This usually
represents warm air riding over cold air in front of a warm front.
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Low Clouds - These extend from 6500 feet down to earth's surface.
Stratocumulus (Sc) - Globular masses or rolls. These are gay or whitish.
These almost always have dark parts. These have a thick layer like appearence. These
could form into Nimbostratus.
Strong winds occur underneath the waves or rolls of the layers. Under the
thick parts strong updrafts can occur. The air inside the layer is also
turbulent.
Stratus clouds are low clouds with a uniform sheet or layer like appearence.
- Stratus(St) - Low , uniform layer of clouds resembling fog but not
going down to the earths surface. Generally, gray, can produce a drizzle or light snow.
Not a good indicator of weather.
Nimbostratus (Ns) - Low , shapeless clouds, dark gray in color.
Produces constant rain and or snow. Sheets of rain can often be seen.
Wind is also associated with these clouds.
These can block out the sun and or moon.
The clouds below are classified as low clouds however, the ones below
are at times, exceptionally low clouds. The range is 1600 feet to
mean high of 20,000 feet. These are also clouds with vertical development.
Cumulus (Cu) - Dense, dome-shaped, puffy looking clouds. Typically
known as the cauliflower puffs. If there is little or no vertical development
the weather should be fair however, these can develop into cumulonimbus. They
are usually white at the top and darker or gray at the bottom.
Cumulonimbus (Cu) - Cauliflower , towering clouds with cirrus veils on
top. These are known as the "thunderheads". Stormy, windy weather with heavy rain.
These can also have the anvil looking top which indicates VERY high winds.
The tops can extend beyond one hundred thousand feet.
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Fog, Dew Point , Relative Humidity and More
Fog - Fog is essentially a cloud resting on the surface of the
earth. It consist of water droplets that are suspended in the air
and can not be differentiated between each other. So, is a VERY light
rain in some respects. Fog usually forms from the bottom up and the land or water
must be cooler than the air next to it, and this air must be colder than the
air above.
Types Of Fog
- Radiation Fog - This is formed by the cooling of nearby land. This happens on a clear
night as the result of the radiated heat on the ground going up the clear
sky. This is often called ground fog. In order for radiation fog to exits
the winds must be relatively calm, the sky clear, the air must be moist, the air
next to the surface of the earth must be colder than the air a short distance up.
Radiation fog is most prevalent in the middle and high latitudes.
- Advection Fog - This is formed as a result of warm air flowing over
the cooler waters of an ocean or lake. May form day or night and in any season
and is prevalent over the seas.
- Coastal Fog - Warm ocean air is carried across coastal waters. It may
blanket an entire coastline.
- Precipitation Fog - The warm raindrops having fallen through a colder
air layer can make the air mass reach its saturation point and fog will then form.
This is typically known as "Frontal or Rain" fog.
- Steam Fog - Usually on large rivers such as the Mississippi or the Ohio
river. This is usually a problem for boaters in early Autumn. Cold air passes over warm
water and in so doing creates vertical air currents. This creates something we refer
to as "steaming". Much like steam from a hot cup of coffee.
- Sea Smoke - In the winter cold air blows off the land over warmer water can
create very thick fog known as Sea Smoke.
Water evaporates into the air from the oceans, lakes and rivers. This water can
exist in three forms in the air; vapor, liquid and solid.
Saturation- Is the point at where the air mass will not hold absorb any more water.
The higher the temperature, the more water vapor the will hold before it is said
to be saturated.
Relative Humidity - This is a measurement of percentage. This is based on
the maximum (saturation point) amount of water vapor present before the dew point
or a 100% is reached for that air temperature. This maximum
amount (which is not the same measurement
as relative humidity but is the saturation point) decreases with a decrease
in temperature. This means that the number, whatever that is, for that
air mass at that temperature
will decrease as the temperature falls. This means that it will
allow for less water vapor before condensing.
The relative humidity of a mass of air (a percentage) increases as its
temperature falls. This means as the temperature falls within an air mass
the relative humidity percentage will go up. When that percentage
some of the moisture condenses into a visible form. The temperature at which
this occurs is called the Dew Point.
Remember humidity is the amount of water vapor in the air. Relative
humidity is ratio of the amount of water vapor in the air to the saturation point or 100%
humidity.
The air becomes saturated , the water will condense become liquid. The
condensation takes the form of fog, dew, rain.
Apparent Wind - Wind measured in direction or degrees from the bow also
measured is the speed of the wind.
Barometer - Each day there is a normal rise and fall occuring with highs
at 10:00 and 2200 hours. Low at 0400 and 1600 hours. The average change
during these times is
about .05 inch or pt 01 inch per hour.
A large drop means strong winds
The violence and speed of an approaching storm are
indicated by the rate and the amount of fall of the barometer.
If the average fall per hour the barometer is .02 to .06 the distance
from the center of the strom is roughly 150 to 250 miles.
If the fall is 06,08 or 1.2 the center is 100 to 150 miles away. If it is
2 the storm is 50 to 80 miles away.
If on a clear day the barometer rises sharply prepare for strong winds.
A falling barometer and easterly winds means bad weather.
Rising barometer with west winds is fair and clearing weather.
Winds -
When the tree's are swaying and the flag is blowing straight out you
can estimate the winds at 12- 22 Knots.
If you hear the wind whistling and tree's swaying hard or white caps
everywhere the wind is 22-27 knots.
Tricks Of The Trade
Am Radio You can often hear a storm coming when you tune to any am radio station that
is not designated.
Trees - If you are in sight of land, look at the trees, prior to a storm they will
turn their leaves over making the tree appear to be a lighter green. A few areas
of light green on a tree mean a small rain storm. When the majority of the tree
is light green you can bet a strong storm is coming.
Wind Chill - If you are out on your boat and feel a small cool breeze at your ankles
a small shower is coming if the breeze is near your knees and stronger a large
storm is brewing and headed your way.
Anvil Top - When you look at an Anvil cloud you may notice a wisp shape across
the front this indicates strong winds at the surface.
Timing Thunder - Note the time between a lightning flash and ITS thunder than
multiply by 2 (or divide by 5) and that will tell you how far away it is in
statue miles . Remember that sometimes there is so much lightning that it may be
difficult to pinpoint a particular bolts thunder.
For More Weather Information Please Ask For Our Weather CD.
Lightning
Lightning has fascinated and excited humans for as long as they
have watched the skies. Meteorologists know the cloud conditions
necessary to produce lightning, but cannot forecast the location
or time of the next stroke of lightning from a storm. At any moment,
there are as many as 1800 thunderstorms in progress somewhere on the
Earth, and each is producing deadly lightning.
As the thunderstorm forms, it produces ice in the upper
cloud. The formation of ice in a cloud is an important
element in the development of lightning. Those storms that
fail to produce large numbers of ice crystals may also fail
to produce lightning. Strong rising and sinking motions within
the cloud are important too, as they enhance collisions among
cloud particles causing a separation of electrical charges.
Positively charged ice crystals rise to the top of the thunderstorm
and negatively charged ice particles and hailstones drop to the middle
and lower parts of the storm.
As the differences in charges continue to increase, positive
charges rise up taller objects such as trees, houses, and telephone
poles. The charge can also move up you, causing your hair to stand on
end! This is natures way final way of warning you that lightning can
strike very soon near you.
The negatively charged area in the storm sends out a charge
toward the ground called a step leader. It is invisible to
the human eye and moves in steps towards the ground. It takes
less than a second for lightning to get close to the ground,
and when it does it is attracted by all of the positively
charged objects causing a channel to develop. You see the
electrical transfer in this channel as lightning. There may
be several repeated transfers of electricity within the channel.
These are observed as flickering lightning.
Lightning Medical Impacts
Lightning usually claims only one or two victims at a
time and usually does not cause the mass destruction left
in the wake of tornadoes or hurricanes. Lightning generally
receives much less attention than any other weather hazards.
During a thunderstorm, each flash of cloud to ground
lightning is a potential killer. However, lightning deaths
can be prevented only if people are aware of the dangers and
seek shelter in a building or a hard topped vehicle.
Lightning can strike as much as 10 miles away from
the rain area in a thunderstorm. That is about the
distance that you are able to hear the thunder from
the storm. If you can hear the thunder from a storm, you
are close enough to be struck by lightning.
Where organized sports activities are taking place,
coaches, umpires, referees, or camp counselors must protect
the safety of the participants and spectators by stopping
the activities sooner so that participants and spectators
can get to a safe place before the lightning threat becomes
significant.
Lightning Facts
An average of 87 lightning fatalities are reported
each year between 1959 and 1995.
About 10% of the people struck by lightning are killed ...
This leaves the other 90% with various types of injuries.
The primary cause of death from lighting is cardiac arrest.
Unlike high voltage electrical injuries with
which massive internal tissue damage may occur,
lightning seldom causes substantial burns.
Most lightning burns are caused by objects such as rainwater,
sweat, metal coins, and necklaces being heated up and causing
the burn.
Lightning tends to cause injury to the nervous system and
may affect any or all parts of the nervous system.
If the brain is affected, the result is often difficulty
with short term memory, coding new information, and accessing
old information.
Most lightning injuries and deaths can be prevented with
advance planning, being aware of the developing weather situation,
and good common sense.
NOAA Weather Radio can help keep you informed with the
latest thunderstorm information and safety reminders.
Lightning Safety
Being outdoors is the most dangerous place
to be during a lightning storm. The National
Weather Service advises that when you hear thunder
or see lightning to quickly move indoors or into a
hard topped vehicle and remain there until well after the
storm has passed.
Any location is dangerous during a
lightning storm, however some areas are
more dangerous than others. Some of the
riskiest locations include:
Anywhere near the water:
Boating
Fishing
Swimming
Activities on the Beach
Areas near tall trees:
The Golf Course
Picnic Areas
Hiking Trails
Isolated tall trees pose the greatest danger!
High terrains such as hill tops and ridges
High places such as house roofs during construction
Open areas like fields
Dangerous situations can arise when big groups of people
come together outdoors during a lightning storm.
This includes baseball, football, soccer, and tennis
games, as well as community fairs and outdoor festivals.
It is important that everyone know some
outdoor and indoor safety rules.
Outdoor Safety Rules
Knowing outdoor safety rules can help save your life
or that of loved ones.
When lightning approaches, get inside a completely enclosed building.
Carports, open garages, storage sheds, metal sheds, and covered patios
are not safe shelters.
If no enclosed building is available, get inside a hard-topped,
all metal vehicle.
Get out of the water! Get off the beach and out of small boats
and canoes. If caught in a boat, crouch down in the center of the
boat away from metal hardware. Avoid standing in puddles of water,
even if wearing rubber boots. Thunderstorm winds create large waves
and turbulent water, so please wear a life jacket!
If you cannot reach shelter, avoid being the tallest object in the
area. Do not take shelter under an isolated tree or the tallest trees
in the area. If you are in the woods, find shelter under the shorter trees.
If only isolated trees are nearby, crouch on the balls of your feet.
A rule of thumb to follow is to stay twice as far away from a tree
as it is tall. Don't lie on the ground.
Avoid caves or overhangs. The ground current from lightning is very
strong and can jump the Gap.
Avoid leaning against vehicles and get off bicycles and motorcycles.
Indoor Safety Rules
When lightning strikes a building, house or other structure,
it follows metal conductors such a electrical wiring, plumbing,
and telephone lines from the structure to the ground. When this
process occurs, it usually leaves the inhabitants unharmed.
Once lightning enters the home it can surge through
the electrical, phone, plumbing, and radio/television
reception systems. It can also travel through any metal
wires or bars in concrete walls or flooring as well as
windows and doors. It is important to avoid these conductors
during an electrical storm.
Phone use is the leading cause of lightning injuries
within the home. Lightning can travel long distances in
both phone and electrical wiring, especially in rural
areas where other conductors are limited.
Basements should be used with caution during thunderstorms
because they usually contain conductors. Avoid contact with
washers and dryers since they not only have contacts with
the plumbing and electrical systems, but also have an electrical
path to the outside through the dryer vent. Concrete floors
should also be avoided as they usually contain some form of
reinforcement which can easily become electrified by a nearby
lightning strike. Avoid bathing during a lightning storm as
the household plumbing can carry a deadly current.
Hurricane - Also known as tropical cyclone.
Hurricanes are not related to warm or cold fronts.
Hurricanes have winds in excess of 74 mph.
A tropical depression is a closed circulatory system that has winds between
20 mph and 73 mph.
Isobar - Lines connecting points of equal barometric pressure.
- Small Craft Advisory:
Observed or forecast winds of 18 to 33 knots
Small Craft Advisories may also be issued for hazardous sea
conditions or lower wind speeds that may affect small craft operations.
Issued up to 12 hours ahead of conditions.
(There is no legal definition of the term "small craft.")
- Gale Warning: Observed or forecast winds of 34 to 47 knots.
- Storm Warning: Observed or forecast winds of 48 knots or greater.
- Tropical Storm Warnings: Observed or forecast winds of 34 to 63 knots associated with a tropical storm.
- Hurricane Warning: Observed or forecast winds of 64 knots or higher associated with a hurricane.
- Special Marine Warning: Observed or forecast winds of 34 knots or more associated with a squall or thunderstorm and expected to last for 2 hours or less.
*Issued up to 24 hours ahead of conditions.
THERE IS NO SUBSTITUTE FOR KNOWING THE RULES OF THE ROAD !
ONE OF THE MOST SOUGHT AFTER RULES OF THE ROAD CD IS NOW HERE !
WHY CHOOSE THIS CD?
- This is the ONLY CD With a 90% SUCCESS rate passing the Captain's Exam.
- It is the ONLY CD written by Instructors in an easy to understand format.
- Captain Aquatic has personally tested ALL Rules Of The Road Cd's on the market and only approves this one.
- It is the ONLY CD that comes with full instant access to USCG Approved instructors for ANY questions you
have as you learn.
- NO OTHER CD DOES THAT. NONE.
- IT IS THE ONLY CD ENDORSED BY OLD SALTS NETWORK, MMCA AND CAPTAIN AQUATIC. IT HAS WON NUMEROUS AWARDS FOR SUCCESS RATE.
- WEEKEND BOATER-This CD/DVD teaches the Rules Of The Road in an EASY to understand format and comes
with FULL instant access to USCG Approved Instructor to answer ANY questions you have while you go through
it.
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