Stu Ellis Farmgate Blog: Will It Ever Rain Again? Oh, Really. June 27th 2012

Stu Ellis, formerly with University of Illinois Extension, serves as the Farmgateblog.com blogger and editor. Ellis has been a presence in Illinois agriculture for more than thirty years and he brings an impressive array of credentials to his new position.

The majority of the Cornbelt has suffered under a stifling drought, despite the fact everyone had counted on the La Nina weather of the past two years shifting to an El Nino pattern that would be more conducive to better crops.  However, the expected rains have not been forthcoming and the needed abundant crop yields are withering daily.  Will this weather continue for the rest of the year, or can we expect any changes?

The forecast for the current week remains hot and dry with temperatures in the 100-degree range for parts of the Cornbelt.  USDA’s crop ratings tumbled substantially Monday and will likely do the same again next Monday.  However, weather models are pointing to more moderate weather with moisture beginning next week.  While an El Nino weather pattern will not come overnight like a cold front with thunder and lightning, the weather will be shifting to a wetter pattern, says Iowa State University economist Steven Johnson.  In his recent newsletter,  Johnson’s thesis is that you should still hold out hope for the weather to change, even if it was not on the growing cycle of most of this year’s Cornbelt crops.

Earlier this month Johnson said the Climate Prediction Center reported there is a 50% chance that El Nino conditions will develop in the second half of 2012.  While a 50-50 chance of something is not great, keep in mind that percentage has been rising steadily for a number of months, and now having a six month window identified for the change to happen is progress.  The Climate Prediction Center is part of the National Weather Service and reports, the“The CPC/IRI forecast calls for ENSO-neutral conditions through JAS (July-August-September), followed by an approximately 50% likelihood for El Niño during the remainder of the year.”
Johnson says El Nino summers tend to provide corn yields that are above trend lines, and he pointed to 2004 and 2009, which had the highest yield averages.  Whether there will be enough left of this summer to make a difference is uncertain.  But the atmosphere is confused as well, says Johnson, because of the rapid demise of La Nina and the stalled arrival of El Nino.  He quoted weather sources that indicate the atmosphere is lacking energy and is the result of the absence of either weather pattern now.  Johnson says as the El Nino slowly arrives (not a weekend phenomenon) the stagnant dry condition should slowly abate.  That shift will ease the dryness in the US, Russia, and China, while the wet conditions in India and Southeast Asia decline.  With a forecast for change, but change that is slow in coming, there will be continued futures price volatility, says Johnson.  He expects current USDA yield estimates to decline, because “they appear to be too high.”
Johnson says that after two years of La Nina, moisture has been removed from the atmosphere and any rain events are much weaker, which may be seen in the minimal showers that have periodically been recorded.  And he adds that when there is a rapid departure of either a La Nina or El Nino, the weather stagnates until one pattern or another regains control. Thus, the hot and dry holding pattern we have seen for several months.
With the neutral pattern we have been in since April, Johnson says weather researchers have been looking for indications that either a La Nina will return again or an El Nino will move in to dominate the weather.  He says the latter would be a welcome change for production agriculture, but would also impact the commodity market because it would point to a return to wetter conditions also for South American agriculture and temper the bullish prices of the past year.

He says the next indication of whether the current neutral conditions are giving way to an El Nino will come about July 10 when the National Oceanic and Atmospheric Administration will report the latest sea surface temperature data used for predictions.

Summary:
Weather patterns change slowly, but in the shift away from La Nina, the current neutral condition has left the atmosphere with little moisture and little energy.  Subsequently, the hot and dry conditions that have plagued much of the Cornbelt have not been driven out by the cooler and wetter conditions of El Nino.  While there is a 50% chance of an El Nino developing in the second half of 2012, the chances have increased over the past few months.