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Old 30-09-2005, 06:48   #1
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Weather Maxims


The trouble with weather proverbs, rules of thumb, and maxims, is not so much that they're all wrong - but that they're not all right, for all times in all places.
The following explanations represent a very limited portion of weather science.
While they may not transform you into an expert, they should help you to understand how you can predict major meteorological events a few minutes, hours, or even days in advance.

Expect cloudy skies and uncertain weather when:
* barometric pressure decreases;
* night temperature is higher than usual;
* clouds are moving in different directions at different altitudes;
* small hair-like clouds are present high up in the sky;
* in summertime, clouds turn dark in the afternoon.

Expect showers when:
* cumuli (small cotton wool-like clouds) form rapidly in early afternoon (spring or summertime).

Expect good weather when:
* barometric pressure rises;
* temperature decreases rapidly during the afternoon.

Expect prolonged good weather when:
* the setting sun is like a fire ball and you can look at it directly;
* barometric pressure remains constant or rises slowly;
* morning fog dissipates within two hours of sunrise;
* the sun turns red when it sets.

High-Pressure systems are associated with clear skies and low probabilities of rain, while
Low-Pressure systems are associated with clouds and high probability of rain.

The way the wind direction changes can help predict the weather:
"A veering wind will clear the sky; a backing wind says storms are nigh."
A backing wind indicates the approach of a low pressure cell from the southwest.

Buys-Ballot Law: Since atmospheric pressure helps determine the weather, knowing from which way the wind is blowing can help you to locate where highs and lows are relative to your position. For example, if you stand with your back to the wind, a high pressure cell will probably be to your right, and a lower pressure to your lef. If your right is west, then you can predict fair or improving weather, because weather systems usually move from west to east.(Northern Hemisphere only)

Boating Weather Safety Rules (from NWS/NOAA)
* Keep an eye out for the approach of dark, threatening clouds, which may be associated with thunderstorms; a steadily increasing wind or sea; any developing decrease in visibility such as fog; and any increase in wind velocity opposite in direction to strong tidal current. A dangerous rip tide condition may form steep waves that can breach a boat.
* Check radio weather broadcasts for the latest forecasts and warnings.
* Heavy static on your AM radio may be an indication of nearby thunderstorm activity.
* If a thunderstorm catches you off guard, remember that not only gusty winds but also lightning poses a threat to safety.
A. Stay below deck if possible.
B. Keep away from metal objects that are not grounded to the boat's protection system.
C. Do not touch more than one grounded object simultaneously or you may become a shortcut for electrical surges passing through the protection system.
D. Put on a life jacket and prepare for rough waters.

E. & O. E.

Gord May

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"If you didn't have the time or money to do it right in the first place, when will you get the time/$ to fix it?"

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Old 30-09-2005, 14:23   #2
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I had the pleasure of working with a professional meteorologist back when I was in school. One of the areas he had a personal interest was weather maxims. He did a lot of actual research to see how true they really were in terms of percentages. Actually they are correct a fair amount of the time but far less than a real local forecast.

So while better than nothing, they are are never a lot to bet the crew and vessel with. If you could take the total of all the maxims you selected they do actually do a fair job of generalizing the weather based on actual fact.

The real problem is the measurements you can take where you are is not a good representation of the weather not where you are not. Unfortunately, the weather all comes from some where you ain't. I think real professionals have some degree of difficulty with forecasting the weather.

One good piece of trivia:

The weather tomorrow will be like today is 85% correct.

Paul Blais
s/v Bright Eyes Gozzard 36
37 15.7 N 76 28.9 W
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Old 01-10-2005, 05:44   #3
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How did sailors, farmers, and others whose lives and livelihoods depended on the weather, and who lived in an era before satellites, radar, and weather balloons, make sense of a force as huge and complex as the weather?

Largely by paying attention to patterns.

Though a constantly changing, shapeless swirl of water vapor, temperature, and barometric pressure, "the weather" becomes visible, or observable at least, in the guises of wind, rain (as well as snow, sleet, hail, and fog), and cloud formations. By noticing and remembering conditions prior to rough weather, these old-timers were able to impose some order on their experience of the world and even prepare for impending confrontations with Mother Nature, whether they were three days from land in the North Atlantic or trying to get the hay in before a summer thunderstorm in the heartland.

Red sky in morning - sailors take warning.
red sky at night - sailors delight.

What does the rhyme mean, and is it true?
As a matter of fact, the saying often holds true in the North America. Because the weather patterns in N. A. generally move from west to east, clouds arriving overhead at sunrise will make the sky will appear red, signaling a storm "moving in". When the storm eventually passes, the sky will clear in the western sky. If sunset occurs simultaneously, the light will cast a red glow on the clouds above, now moving towards the east.

Weather Humor:

William Bonner, an authority on forecasting with the University Corporation for Atmospheric Research in Boulder, Colo, once said, ”If the visibility is 15miles and there is not a cloud in the sky, you can bet it's not going to rain in the next 30 minutes.”

Meeorologist Jeff Haby claims that our actions actually determine the weather: ”I see that when people dress more warmly the weather will turn more cold, and when people dress less the weather will turn warmer. The weather is watching you!”

Get a rock from somewhere, and place it on your dock, boat, or anywhere you like. That’s all you have to do, and your ready for forecasting! Hang it from a chain, and get the supplemental predictions.
[If you dont want to use a rock, you can use a horse, works just as well ]
~ If it's dry ---- Weather's Clear
~ If it's wet --- It's Raining
~ If its white -- It's Snowing
~ If it's gone -- Hurricane !
Supplemental (chain-hung rocks)
~ If it's swaying --- Wind is blowing.
~ A shadow under the rock --- Sun is shining.
~ If it's jumping up and down --- Earthquake !

So, you thinks it’s rainy where you are?
World's Record Precipitation Events
Duration - Depth (Intensity) - Location - Date
1 min - 1.50" (90"/hr) - Barot, Guadeloupe - Nov 26, 1970
8 min - 4.96" (37.20"/hr) - Füssen, Bavaria - May 25, 1920
15 min - 7.80" (31.20/hr) - Plumb Point, Jamaica - May 12, 1916
20 min - 8.10" (24.30/hr) - Curtea-de-Arges, Romania - July 7, 1889
42 min - 12.00" (17.14/hr) - Holt, MO - June 22, 1947
Gord May
"If you didn't have the time or money to do it right in the first place, when will you get the time/$ to fix it?"

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Old 09-01-2006, 06:10   #4

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Hey gord
i sent a friend to your photos for the weather basics article and its gone
whats up
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