Texas Wheat Fortunes Hinge on La Niña

November 3, 2011

 

If a strong La Niña unfolds this winter Texas wheat production is doomed, but a weakening La Niña if it developed would increase rainfall, improving prospects in the number 3 US hard red winter wheat state.  Texas is more sensitive to La Niña rainfall fluctuations than any other winter wheat state,  

This report focuses on 5 cases when Texas planting conditions were severely delayed by fall drought.   The objective was to see if a productive harvest is possible after a poor start.   Three of the 5 years made a poor wheat crop,  but  wheat prospects improved with heavy winter rainfall the other 2 growing seasons.

  

 

Very dry planting conditions this fall slowed Texas wheat germination.  Only 38% of wheat was sprouted and   “emerged"  by October 30.     This was the second-slowest emergence rate in 27 years of USDA records, slightly ahead of 34% in 2000.

 

Five Fall Drought Analogs in Texas

The 5 analog years for fall drought and retarded wheat development were 1990-91, 1992-93, 1999-2000, 2000-01 and last fall,  2010-11.    Low wheat production would seem unavoidable from intense fall drought.  Amazingly, profitable wheat harvests were obtained in 1992-93 and 2000-01.   

Heavy winter precipitation was the key to success, restoring field moisture for wheat growth in the spring.   Winter coolness was beneficial also, conserving field moistures with lower evaporation.  Heavy winter rainfall turned around Texas wheat prospects:
    

 

 

 

Three Bad Harvests With Winter Drought

The 3 poor outcomes in 1990-91, 1999-00 and 2010-11 occurred from worsening drought, fall through winter.  Even though rainfall picked up in the spring,  it was too late to rescue wheat from a poor harvest.  Conditions were particularly dry last winter with a strong La Niña in effect.   Texas producers harvested only half a normal crop in the 2010-11 harvest.  Incredible drought lasted more than 6 months. 

 

 

Forecasts on La Niña  Vary

The Texas rainfall study for potential drought is  very important since not all scientists agree on the strength of La Niña in the upcoming winter.    Some international models predict strong warming in sea surface temperatures, turning into El Niño by March.

Presently, conditions are on the threshold of a “strong”  La Niña with sea surface temperatures 1.1 C below normal in the Niño 3.4 region.      The US Climate Prediction Center predicts La Niña will continue strengthening  this winter bottoming out near 1.5 C below normal.    Only minor warming is projected into spring 2012. 

The Australia Bureau of Meteorology (BOM) disagrees  saying “current observations indicate this La Niña will be considerably weaker than the strong 2010-11 event.”    Pacific Ocean cooling temperatures are evolving slowly,  Bureau scientists said in comments published October 26 in the bimonthly report. 

To see more La Niña forecasts click on this link:  http://www.martellcropprojections.com/CropProductionReports/La-Nia-Late-October-Update-