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The Palmer Drought Index

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At this time, in Oklahoma, we are experiencing a serious drought. Ponds are empty, lakes severly below normal levels and fire danger at extreme levels. Already, 500,000 acres have burned in NE Oklahoma and 30 structures including 18 homes have been destroyed. Is there an end in sight? I started researching the drought situation and realized how little I knew about the resources available to the public for doing so. Since I didn't know much about it, I figure some of you might be curious too. I decided to post a portion of my findings here. The following is copied from NOAA's Drought Information Center concerning the Palmer Index:

The above map is produced by NOAA and is based on the Palmer Drought Severity Index.
The Palmer Index is most effective in determining long term drought—a matter of several months—and is not as good with short-term forecasts (a matter of weeks). It uses a 0 as normal, and drought is shown in terms of minus numbers; for example, minus 2 is moderate drought, minus 3 is severe drought, and minus 4 is extreme drought.

The advantage of the Palmer Index is that it is standardized to local climate, so it can be applied to any part of the country to demonstrate relative drought or rainfall conditions. The negative is that it is not as good for short term forecasts, and is not particularly useful in calculating supplies of water locked up in snow, so it works best east of the Continental Divide.

Another cold front moving through

Report for 11/27/05 part II