Thursday, October 18, 2012

Winter Outlook for 2012-13

The Climate Prediction Center released its early outlook for the upcoming winter this morning.  Much of the western U.S. will see warmer than normal temperatures while cooler than normal temperatures are expected for the Florida peninsula.  Equal chances of above or below normal temperatures are forecast for much of the East.

Much of the West will be dry particularly in the Pacific Northwest.  The Central Gulf region is expected to be wetter than normal.  This may help ease the drought in Georgia and South Carolina.

Click on either graphic for a larger version or go here for the temperature map and here for the precipitation map.  Image Credit: NOAA\CPC.

A weak El Nino is expected to persist into the winter months and may strengthen a little into the end of the year.  However, it is not expected to exert a great influence on the weather.  The outlook tilts toward conditions usually encountered in an El Nino.

One caveat that must be acknowledged is that the outlook does not include impacts that may arise from a changing Arctic.  Recently the Arctic Oscillation and North Atlantic Oscillation have both trended toward negative phases.  If this persists into the winter, then the East will be colder than normal with a more volatile weather pattern (meaning more snowstorms).  However, these oscillations cannot be forecast more than two weeks in advance (bummer!).

Thus, the outlook for South Carolina is for near normal conditions on both temperature and precipitation.  However, this may belie the true picture.  The evolving pattern is more likely to provide the state with big swings in temperatures with occasional wet weather system moving in from the Gulf or Midwest.  Coastal storms may be more of a problem in mid to late winter.  There will likely be some relief from the dry conditions.

What does this mean for the ongoing U.S. drought?

The drought update for the U.S. issued today shows that 75% of the country is in some form of drought.  This is an improvement over three months ago when the figure was 81%.  However, 19% of the country is still in an extreme or exceptional drought and this includes parts of central Georgia.

Image Credit: USDA.

The National Oceanic and Atmospheric Administration (NOAA) updated its drought outlook through the end of January 2013.  Much of the western and central U.S. will see a persistence of drought and it should get worse in the Pacific Northwest.  There is likely to be some improvement over the eastern third of the nation.

Image Credit: NOAA.

Wheat growing areas could be impacted by the ongoing drought in the central U.S.  The western corn belt is also likely to be impacted by the continuing drought.  However, the drought should ease in the eastern corn belt.  Keep in mind that the UN is forecasting a developing global food crisis in 2013 impacting more of the third world nations due to agricultural concerns in places like the U.S.