Origin of Wind

NWS - Wind is simply the air in motion. Usually when we are talking about the wind it is the horizontal motion we are concerned about. If you hear a forecast of west winds of 10 to 20 mph that means the horizontal winds will be 10 to 20 mph FROM the west.

Although we cannot actually see the air moving we can measure its motion by the force that it applies on objects. For example, on a windy day leaves rustling or trees swaying indicate that the wind is blowing. Officially, a wind vane measures the wind direction and an anemometer measures the wind speed.

The vertical component of the wind is typically very small (except in thunderstorm updrafts) compared to the horizontal component, but is very important for determining the day to day weather. Rising air will cool, often to saturation, and can lead to clouds and precipitation. Sinking air warms causing evaporation of clouds and thus fair weather.

Pressure gradient is the difference in pressure between high and low pressure areas. Wind speed is directly proportional to the pressure gradient. This means the strongest winds are in the areas where the pressure gradient is the greatest.

Cloud Classifications

NWS -  By convention, clouds are vertically divided into three étages (levels); low, middle, and high. Each étage is defined by the range of levels at which each type of clouds typically appears. The types of clouds are...

Cirrus (Ci), Cirrocumulus (Cc), and Cirrostratus (Cs) are high level clouds. They are typically thin and white in appearance, but can appear in a magnificent array of colors when the sun is low on the horizon.

Altocumulus (Ac), Altostratus (As), and Nimbostratus (Ns) are mid-level clouds. They are composed primarily of water droplets, however, they can also be composed of ice crystals when temperatures are low enough.
Cumulus (Cu), Stratocumulus (Sc), Stratus (St), and Cumulonimbus (Cb) are low clouds composed of water droplets.

If you recall that the polar and subtropical jet streams are the dividing points between the polar, temperate, and tropical regions you will also notice the maximum height of the tropopause also decrease in each region as one moves from the equator to the poles.

Level Polar Region(PR), Temperate Region (TR), Tropical Region (TrR)

High Clouds - PR10,000-25,000 feet (3-8 km)  TR16,500-40,000 Feet (5-13 km)  TrR20,000-60,000 feet (6-18 km)
Middle Clouds PR 6,500-13,000 feet (2-4 km) TR 6,500-23,000 feet (2-7 km) TrR6,500-25,000 feet (2-8 km)
Low Clouds PRSurface 6,500 feet (0-2 km) TRSurface-6,500 feet (0-2 km) TrRSurface-6,500 feet (0-2 km)