Tuesday, July 24, 2012

The Drought Eases In South Carolina

It takes time to move into a drought.  Likewise, it takes time to move out of a drought.  The recent rains have definitely eased the pain for South Carolina.  According to the latest drought monitor from the USDA only 22% of the state is in a severe drought or worse compared to 32% the previous week.  Much of the Pee Dee region is out of the drought completely.

Click on image for a larger view.  Image Credit: USDA.

The first four months of the year were a continuation of the drought that started in January 2010.  Only four months out of the past 28 months had been wet by the end of April.  The total rainfall by then for 2012 was 8.71 inches at the Columbia Metropolitan Airport or just over 2 inches per month.

However, the weather pattern began to change to a wetter one in May.  Columbia received 15.50 inches of rain from May 1st through July 23rd at the airport.  The city received 17.61 inches during the same period.  July is normally the wettest month of the year, but we are running above normal this year.

The hardest hit area in the state continues to be the west central section of South Carolina near the Savannah River.  Parts of Aiken, Edgefield, Greenwood, Abbeville, and all of McCormick counties are still in an extreme drought.

While the situation improves in South Carolina it is getting worse for much of the country.  The USDA reported last week that much of the country was now experiencing some form of drought.  A record 81% of the contiguous U.S. was in an incipient drought or worse.  That was up about 2% from the week before.

Click on the graphic or table to see a larger view.  Image Credit: USDA.

Back in February I began advising people to consider backyard gardens as a means to save on their food bill.  The reason was that it was apparent that many of the vegetable growing areas would be stressed this year.  I did not expect the Corn Belt to be hit so hard by a heat wave (in some cases record heat) and a flash drought.

The graphic below shows the stress for crops across the country.  It is a map of the Evaporative Stress Index (ESI) which is a drought index based on remotely sensed evapotranspiration (ET).  The ESI quantifies anomalies in the ratio of actual to potential ET (PET) mapped using thermal-band imagery from geostationary satellites.  The map is an average for the month prior to July 18, 2012.

A larger view can be seen by clicking on the image.  Image Credit: USDA, ARS-HRSL.

It clearly shows the stress for the Midwest drought as well as the high plains.  You can see the green areas over South Carolina indicating less stress to the crops.  There are still pockets of stress in the state, but the situation is improving.

The National Oceanic and Atmospheric Administration (NOAA) is forecasting some improvement in the drought for South Carolina.  However, much of the country is likely to see the drought persist or get worse.  This is particularly true for the Midwest where August to forecast to be hotter and drier than normal.

Seasonal Drought Outlook.  Image Credit: NOAA\CPC.

Drought conditions are likely to improve further for South Carolina later this year and through the winter.  This is because El Niño is likely to be in progress.  El Niño’s tend to produce cooler and wetter conditions for the southern states during the winter.  No it doesn’t mean it will snow this winter, but the last El Niño did produce a couple of snowstorms in the winter of 2009-2010.