General Weather Information

"My windmeter is measuring a much lower windspeed than the local reports"

Windspeed is simultaneously simple to measure, and complicated. When you see local measurements of windspeed, it is taken at a local airport, or in an open area. With no obstructions, wind will often be higher in those locations than in the city. They also do not record windspeed each second, but rather an average windspeed. Additionally, official windspeed is measured well above the ground; the Federal Standard is 10 meters (32.8 feet).

In most cases, what is needed is the wind speed where you are, not at the local station. that is why you have a handheld windmeter. If you need to take measurements for other pruposes - reporting to a weather network, determining wind velocity for a wind farm, or general trends of the environment, a different product will be more suitable, where the wind speed can be measured at the appropriate height, and over a longer period.

External References:
http://www.awea.org/faq/wwt_basics.html
http://www.nwstc.noaa.gov/DATAACQ/d.ASOShuman/ASOSHome.htm

"The temperature reading is too high."

The temperature reading does take some time to adjust, and it all depends on the change in temperature from storage to measurement, and the airflow. In very cold weather, if you take a thermometer from a 70 degree house to outside where it is 5 degrees, it will take a long time to register the correct temperature. The plastic case will retain heat, and it takes time for that to adjust. To reduce the time it takes to get a correct reading, wave the windmeter in the air, place it on a conductive surface (metal works well), and avoid holding the case with bare hands.

"Something is wrong with the altimeter; the altitude changes, but I haven't moved it."

You need to first understand how altitude is measured. Most people understand that as you dive deeper in a pool, the pressure increases. You can understand this as all the water above creating the weight on you. Well, the same thing is true of air pressure. Air has a certain weight, and there is a lot of it between the earth's surface and space. You most likely have experienced this if you dramatically increase your elevation - taking off in an airplane (although it is due to pressurized cabins rather than elevation change...) or driving or climbing a high hill or mountain.

Altitude is measured from the change in air pressure. As you increase elevation, there is less air pressure (think of it as less air between you and space). This relationship is basically linear at lower elevations; for every 10 feet increase in elevation the pressure is about 0.01 inHg less, at altitudes below 5,000 ft. You can easily test this: use your altimeter (GEOS11 or Xplorer 4), and set it on the floor. Read the value of the barometer. Now climb one flight of stairs, which would typically be 10 feet. The barometer value will now be 0.01 inHg less.

However, air pressure is not stable, it is constantly changing. When you watch weather reports, you will see references to the High and Low pressure areas. Over the course of several days, or even several hours, the air pressure will change, often by 0.10 inHg. Leaving your altimeter in the same location, a change of pressure by 0.10 inHg will result in a change of 100 feet!

Over a short period of time or periods of little weather change, your altimeter will remain steady. We have tested the Xplorer 4 and GEOS 11 by starting at point A, taking the altitude reading, traveling to Point B at a higher elevation, and returning to point A. This would be a "Point-to-Point" reading. We found the Xplorer 4 will be within +/- 30 feet, and the GEOS11 within 10 feet. Most consumer-grade altimeters have a point-to-point accuracy of +/- 100 feet.

Pilots face this issue with their own altimeters. Everytime they fly, they must calibrate the altimeter to the current air pressure. The GEOS11 and Xplorer 4 include useful measurements for pilots, such as QFE and QNH. This website can explain that information better than I can: http://www.auf.asn.au/groundschool/umodule3.html

External References:
(Layman's Terms): http://www.challengers101.com/Pressure.html
(technical): http://en.wikipedia.org/wiki/Atmospheric_pressure