PNA Index

The Pacific North America Index (PNA Index) describes the differences of the 500 hPa pressure level between the polar and equatorial zones of the Pacific and North America. The pressure difference is very important for the temperature and precipitation situation over North America during winter time.

PNA Index of the last 120 days:

PNA Index of the last 120 days
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Daily values from 1950 to date:

PNA Index since 1950, daily values
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