US Climate Diversity and Weather Patterns

US Climate Diversity

• The US has diverse climates, varying from lush Hawaiian islands to semi-arid deserts in the southwest.
• This diversity in physical conditions leads to a wide variety of natural resources.
• Regional differences in climate affect precipitation and temperature.

Temperature and Precipitation Patterns

• Temperature decreases as latitude increases moving north.
• Precipitation increases as you travel from west to east.
• California (west coast) is relatively warm and dry.
• Florida (east coast) is hot and wet.

Influence of Jet Stream

• The polar jet stream significantly influences US weather.
• It migrates northward in summer and southward in winter, bringing in large low-pressure systems from the Pacific Ocean.
• The Cascade, Sierra Nevada, and Rocky Mountains absorb much of the moisture from these systems before they reach the east coast.
• This leads to significant differences in precipitation levels based on geographic position relative to the mountains.

Orographic Effect

• Orographic effect (rain shadow) refers to the process where mountains absorb moisture from air masses, leading to drier conditions on the leeward side of the mountains.
• Uninterrupted flat land, like the Great Plains, allows air masses to reorganize, leading to potential major clashes that can create violent thunderstorms, especially during spring and summer, and sometimes intense storms (Nor'easters) when they reach the East Coast with heavy rain, wind and snowfall.
• The Great Plains experience extreme climate swings due to these movements.