UGA Extension Viticulture Blog

Outlook for August and Aug-Sep-Oct shows likelihood of above normal temperatures

NOAA’s Climate Prediction Center releases monthly climate outlooks in mid-month showing one-month and three-month outlooks for temperature and precipitation.  They are probabilistic forecasts, which means they tell you the likelihood of above, near or below normal conditions but not how extreme they might get.

For example, in the one-month temperature outlook for August, you see that all of Georgia is in a slight chance of above normal temperatures but less than 40%.  If it were 40%, as in the 3-month map, then there would be a 40% chance of above normal temperatures, a 33% chance of near normal conditions, and a 27% chance [100-(40+33)] of below normal conditions.  The “EC” in the precipitation map indicates equal chances of each category, essentially a crap shoot this time of year since most summer precipitation is driven by small-scale weather patterns like daily thunderstorms or tropical storms with paths that cannot be forecast until after they develop.

The good news is that drought is very unlikely to develop this year, which is great for crops although in some areas rainfall may be too much of a good thing as the grapes ripen.  You can see updated versions of these maps at http://www.cpc.noaa.gov.