How to Make a Weather Station for Your Child
Since much of the work will have to be done outside, where the weather is, you’ll need a waterproof box. Something plastic is great, like a cooler, or you can cover a box with plastic. Attach an inexpensive thermometer to the bottom of the box. Take the box outside and set it on one side with the thermometer in the back. The box should be put somewhere save and sturdy, on the north side of a building where it will get the most shade. Use a rock or something heavy to hold the box in place.
Keep a weather journal to list your observations so that you will be more capable of making weather predictions and forecasts. Once a day, at least, record the measurements from each of your weather instruments at your weather station you will be building. Your weather station will include a journal, barometer, thermometer, hygrometer, rain gauge, weather vane and compass. Keep the weather chart in neat order so that it’s easier to notice weather patterns and certain data.
In your journal make columns down. Draw lines to separate the columns into the following categories: date, time, temperature, barometric pressure, humidity, precipitation type, precipitation amount, and wind direction. Each day record something, even if it’s “zero”, in each column, on each line. For example, if there is no precipitation that day list “none” in the “precipitation type” column.
A barometer is a device that is sensitive to any change in weather conditions. The barometer will stay indoors to get the most accurate readings. To make the barometer you’ll need a glass or beaker with straight sides, a twelve-inch ruler, some tape, a foot-long piece of clear plastic tubing, a stick of chewing gum and some water.
Stand the ruler in the glass making sure the back of the ruler is pressed up against the inside of the glass. Tape into that position or use a dot of hot glue to hold into place. The ruler should be placed to where the numbers can be seen from the front. Place the plastic tube next to the ruler. The tube should not touch the bottom of the glass but should rise about a half-inch from the bottom. Tape or glue the tube to the ruler.
Chew the gum to make it soft and in the meanwhile, fill the glass half full of water. Use the plastic tube as a straw and suck the water halfway up the tube. Hold your tongue over the end of the tube to keep the water in the tube at it’s current level. Quickly move tongue and position the gum over the tube hole to seal it. Mark the ruler to show where the level is inside the tube. When you notice any change in the water level make another mark on the ruler. Over time the water level in the tube will rise and fall. Pay attention to these fluxuations and record them.
The reason the water rises and falls in the tube is because of air pressure exerted on the water in the beaker. As the air presses down on the water in the glass (increased atmospheric pressure) more water is pushed into the tube making the water level rise. When the air pressure decreases on the water in the glass some of the water will move out of the tube making the water level fall. The change in barometric pressure will help you in your attempts to forecast the weather. Decreasing air pressure usually indicates the approach of a low pressure area which generally brings clouds and precipitation. Increasing air pressure normally means that a high pressure area is approaching which usually brings clear or fair weather.
A hygrometer measures the amount of moisture, or humidity, in the air. To build the hygrometer you’ll need a piece of wood or flat styrofoam, 9″X4″, a flat piece of plastic, 3″X3″, such as from a milk jug. You’ll also need 2 small nails, 3 strands of human hair, each about 8″ long, a dime, some glue, some tape, a hammer and some scissors.
Cut the piece of plastic into a triangular shape and tape the dime near the point of the triangle. Poke one of the nails through the pointer near the base of the triangle piece. Wiggle the nail until the pointer moves freely and is loose around the nail. Glue the hair strands to the plastic between the dime and nail hole.
Position the pointer on the wood or styrofoam base about three fourths of the way down the side. Attach the nail to the base with pointer being able to easily spin around on the nail. Attach the other nail an inch from the top of the base, in line with the pointer. Pull the hair strands taut so that the pointer points parallel to the ground. In other words, make sure the point on the pointer is perpendicular to the hair. The hair should hang vertically and the pointer should point perfectly horizontal. Glue the ends of the hair to the nail and trim off any excess.
The hair cells will indicate the level of moisture in the air by expanding and contracting. When the air is moist the hair will expand and lengthen making the pointer angle downwards. When the air is dry the hair will contract and shorten causing the pointer to point upwards. When you make your hygrometer observations each day make a mark to indicate where the pointer is pointing. Over a period of time you’ll be able to see the humidity patterns that will help you with your weather predictions.
A rain gauge is also a necessity for your weather station. The rain gauge stays outdoors but not in the weatherproof box. Having the rain gauge where you can reach it from the weatherproof box will be a big plus. It will make it much easier to record your data if your barometer and rain gauge are in close proximity of one another. The rain gauge consists of a glass beaker or household glass with straight sides and numbers for measuring, a coat hanger or bent wire, and a hammer with nails. Twist the wire or hanger into a spiral that will hold the beaker or glass. Hammer the holder onto a piece of wood or directly onto a fence post or another sturdy object.
Since wind often accompanies rain the rain gauge needs to be somewhere where it won’t blow over and spill. Make sure there are no trees, wires or roof ledge overhead before setting the rain gauge. The edge of a fence or the edge of a pole that doesn’t have wires is a good choice. When the beaker is placed and the rain falls take your measurement and empty the glass.
After you’ve made a weather vane you’ll be able to tell which way the wind is blowing. To make the vane you’ll need a long wooden dowel approximately half the size of a broomstick, an aluminum pie pan, a 12″ ruler, some nails, a metallic washer, a hammer, some glue, a small knife, good scissors, and some wire.
Use the knife to cut a vertical slit at each end of the ruler. The slit should be a half-inch in depth. Directly in the center of the top portion of the stick, hammer a nail all the way through. Turn the wood around several times until the stick easily turns around on the nail. Using the scissors cut the pie plate in two sections: one that is shaped like a triangle and looks like an arrow tip. The other is cut as follows: make a square with one side of the square longer than the opposite side. The two side pieces should angle off to go from the short side to the long side. Glue the head and tail pieces into the cut slots at the ends of the ruler. Be sure the glue has dried well before taking the vane outside.
Attach the weather vane to the dowel rod by placing the metal washer on the end of the dowel then hammering the nail through the ruler and into the wooden dowel. Make sure the vane will spin easily around the nail. Mount your weather vane near the rain gauge if possible. Try to position the weather vane above the fence or pole but make sure the dowel is steady and straight. The head of the pointer will always point in the direction from which the wind is blowing. If the head is pointing to the east, the wind is blowing from the east. Be sure and record your daily wind direction readings in your weather journal.
The compass is the final piece to your weather station and it can be made very easily. To make the compass you’ll need a flat area where the sun shines and there is no shade. A straight stick or dowel, 18 inches long, four heavy rocks the approximate size of golf balls and some small stones for marking.
Locate the flat sunny space nearest your weather station. Dig a hole six inches deep. Bury the base of the stick. The stick should stand up to a height of 12″. Locate where the north is. In the morning, about 7 a.m. or so, place a small marking stone at the end of the shadow that is cast by the stick. Later in the afternoon the shadow should be about the same length as it was in the morning but in a different location. Place a marking stone in this place, marking the afternoon shad9ow. Position your right foot on the morning stone and your left foot on the afternoon stone. Your body now faces south.
Once you have located the southern direction place one of the heavy stones on the ground about a foot in front of the stick. Position a second stone in the north position. Position the other two heavy rocks at the east and west positions. Now your compass uses the sun to show you the directions for weather data.
Use your new instruments to track the weather, wind, rain and other data. Keep the data over a period of time and try to notice patterns on your own. When the wind blows from a certain direction does that mean rain? Does the barometer have to be at a certain reading before the rain will come? Use the weather station and journal as a science project or just to practice being a junior meteorologist.
