Weather Imagery

If you find that your BMW 650 CS/GS/Dakar tail light doesn’t work at all or flickers when riding, chances are the metal power terminals inside the bulb socket are no longer making a good connection with the metal bumps on the tail light bulb. This is a very common problem with the BMW 650 of all makes, models, and years. Fortunately, there is a very easy fix.

Due to excessive vibration, temperature changes, and replacing light bulbs, the two metal power terminal tabs inside the tail light socket deform and get pushed too far back inside the tail light chassis. This prevents the tail light bulb from making good contact with the power terminals and the smallest vibrations can cause the electric connection to break temporarily or indefinitely.

To fix the problem, all you need to do is pry the two metal power tabs forward just a little so that they make a better connection with the metal bumps on the tail light bulb. If you look at the back of the bike, the red tail light casing on the 650 CS/GS/Dakar is held in place with two screws. If you remove these screws the red tail light casing comes off and you have access to the light bulb inside. At this point, turn the ignition on, but you don’t need to start the bike. Remove the light bulb by pushing in and twisting clockwise about 1/8 turn. If the bulb flickered while removing it, then the bent power terminals are most likely the cause.

Looking at the tail light bulb you should see two metal bumps. These bumps need to make a good connection with the two metal power terminals inside the tail light casing. Turn the ignition off and find a small tool that you can use to pry the power terminals forward just a bit. Make sure the bike is off and you don’t want the power terminals tabs inside the tail light casing to touch.

After you have made the adjustment, turn the ignition back to “on” and re-insert the taillight bulb. If the bulb is lit, then you are done. If it still flickers a bit and doesn’t stay lit, then you will need to continue prying the tabs forward until a good connection is made. It took me 4 tries before I fixed mine because I didn’t want to pry them too far forward.

Tornadoes don’t really hop, jump or skip. They can pull back up into the clouds and come back down sometime later, but this usually occurs over a fairly large distance. On a smaller scale, people tend to believe tornadoes can hop or jump over one house while totally destroying the one next to it. While this is true that a tornado can completely destroy one house and minimally damage another right next to it, the real reason has nothing to do with a tornado jumping or skipping. It has to do with the internal structure and varying intensity of a tornado.

The funnel of a tornado is sometimes composed of two or more vortexes which are just like smaller tornadoes that spin around in a circle (as seen in the picture to the left). This kind of tornado is called a multiple-vortex tornado and is almost always responsible for narrow paths of extreme destruction. We normally can’t see the individual vortexes because condensation and debris obscure the internal structure and give a tornado that wedge shape appearance.

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With today’s land starved metropolitan cities expanding further into their rural surroundings, a strange consequence occurs that directly affects the local weather, in particular temperatures and rainfall. No, this doesn’t have anything to do with global warming. Instead, the principal involved has to do with how much of the sun’s energy is absorbed as compared to how much is reflected on a much smaller scale.

As a city increases in size, the amount of heat it absorbs from the sun increases. Vegetation and trees which cool the air through shade and evaporation are replaced with tar roof tops, dark colored roads, and asphalt parking lots which absorb more energy. The sun’s energy is then converted to heat which in turn heats the surrounding air. This is referred to

as the “urban heat island affect“. It has been well documented that cities like Houston, TX and Atlanta, GA are on average 7°F to 9°F warmer than their surrounding environments. In addition, tall buildings and other structures can alter wind patterns which can force the air to rise. Temperature differentials and rising air currents help to destabilize the atmosphere which can create clouds and help promote rainfall.

NASA and the University of Arkansas have used satellite mapping and ground-based weather station readings to figure out how widespread this phenomenon actually is. Turns out, Houston and Atlanta have quite a few days in which the “urban heat island affect” triggers thunderstorms. During the 1996 Olympic Games in Atlanta, scientists were allowed the opportunity scrutinize data collected by the National Weather Service’s ground-based weather collection equipment used to predict weather for the athletes. After scrutinizing the data, meteorologists Robert Bornstein and Qing Lu Lin of San Jose State University discovered 5 out of 9 days of precipitation were caused by the urban heat island effect.

Air that is warmer than the surrounding air tends to be more buoyant and as a result it wants to rise. Such is the case when a city’s temperature is 8°F warmer than the surrounding environment. As the warm air rises, cooler air fills in the void of the hot rising air. If the air contains sufficient amounts of moisture and has a high enough relative humidity level, clouds may form. As these clouds drift downwind, they can further develop and produce rain. NASA has proven that urban heat islands increase rainfall amounts on the down-wind side of the city:

Using the world’s first space-based rain radar aboard NASA’s Tropical Rainfall Measuring Mission (TRMM) satellite, Shepherd and colleagues found that mean monthly rainfall rates within 30-60 kilometers (18 to 36 miles) downwind of the cities were, on average, about 28 percent greater than the upwind region. In some cities, the downwind area exhibited increases as high as 51 percent.

Can this phenomenon be reduced or eliminated? It’s unlikely it will be eliminated and there could be some argument in trying to reduce it. By creating more rain days, cities are showing signs of being more “green” due to an increase in vegetation. Considering cities will only get larger, it’s best to try and understand as much about the heat-island affect so that agricultural tracts of land can be better positioned and city engineers could design more efficient irrigation systems.

In February 1971, Dr. T. Theodore Fujita published a research paper entitled “Proposed Characterization of Tornadoes and Hurricanes by Area and Intensity”. In the paper, he discussed how tornadoes should be rated on a scale to better understand the damage associated with intensity and wind speed. Over the next few years and the super outbreak of 1974, Dr. Fujita’s scale for measuring tornadoes became invaluable and the F-Scale became widely adopted.

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