Last updated: October 5, 2015
Weather Patterns of the Pacific Coast
- Grade Level:
- Middle School: Sixth Grade through Eighth Grade
In this activity, students will learn about weather patterns that help them better understand their water resources.
The weather in the Pacific Northwest is dependent on the Pacific Ocean. Generally speaking, weather in the region is mild, with cool wet winters, and warm dry summers with extremes in temperature and precipitation being unusual. However, despite the moderating effects of the Pacific Ocean, the mountains are very important in terms of the distribution of precipitation across the region and the development of water storage in the form of a snowpack during the summer drought. The mountain, via topographical lifting and the rainshadow effect, causes some areas to be temperate rainforests, while others become deserts.
Condensation: The transition of water vapor into liquid
Dew point: The temperature at which relative humidity reaches 100% and liquid water condenses from the air.
Rainshadow Effect: As clouds pass over the mountains, they drop precipitation on the windward side. But, when the air drops on the leeward side, it warms up, causing the clouds to evaporate again into vapor due to the temperature rising above the dew point temperature. This adiabatic heating and cloud evaporation results in drier conditions on the leeward side of the mountains
Adiabatic Heating: The compression and heating of air as it descends from high elevation to low elevation
Snowpack: The seasonal accumulation of snow in the winter that is available for melting in the spring and summer.
Glacier: A body of compacted ice that flows due to gravity under the weight of the ice above.