Martell's Weekly Weather Wrapup

August 19, 2011 10:31 AM

The following content was provided by meteorologist Gail Martell of

Yield potential is already lost
USDA last week released official yield estimates for corn pegging Illinois at 170 bu. per acre and 3% below trend. Summer heat and drought stress argues for a much lower yield and 8% below trend.

"Rain makes grain" in July, the trade motto goes, referring to heavy rainfall in the key pollination stage. Corn requires .20 inch of water, per day for ideal fertilization, even more when conditions are windy and hot. Very unfavorable pollinating conditions were present this year with extreme heat (4 F above normal) and sub-par rainfall down 25% below average.

Illinois corn was developing very rapidly in August. State corn by mid month was 74% in the dough stage and 30% denting. Advanced development in corn would not be so remarkable, except when you consider state corn was planted 7-12 days late. Premature ripening is a red flag for drought stress and yield reductions.

US rainfall past 50 days

The Illinois corn conditions have been worse than the national average all through the summer growing season. Good-excellent corn peaked at 67% on July 7 and then falling to 50% G-E on August 7. Poor-very poor corn at the same time increased to 17%, and up 8%. We’ve never seen a good crop coming out of mediocre mid August ratings, similar to Illinois’. The average cut in the yield was 7% below trend.

Soybeans Need Rain, Yield Potential Already Lost
Top soybean districts in the heart of the Midwest have experienced worsening drought over the past 6-7 weeks. Most dry are farms in central and southeast Iowa, two-thirds of Illinois and roughly 40% of Indiana. Also worsening by the day are dry field conditions in southern Minnesota, Wisconsin and eastern Missouri. Rainfall is down around 40% below average in 6-7 weeks in hardest hit areas.

Yield potential is already lost. USDA cut the U.S. soybean production 8% in the August report. This is partly due to smaller plantings this season but also from lower productivity in drought. Pod setting was 70% under way August 14.

Heavy rainfall is predicted in the more southern growing areas of the Midwest this weekend, along with the Mid South and Delta. Rainfall may reach 2 inches or more from recurring strong thunderstorms. The forecast is more "iffy" in northern Midwest soybeans however.

The atmosphere in the central U.S. has become more humid and unstable due to a moist air stream the Southwest monsoon wind circulation. Strong thunderstorms erupted this morning in Missouri and southern Illinois. More rain is to come to the lower Midwest and Mid-South from thunderstorms driven by the monsoon.

Sov Econ Trims Russia Grain Harvest Estimate
The respected analysis group Sov Econ has reduced the Russia grain harvest estimate to 87-90 million metric tons (MMT). A crop above 90 MMT is off the table, presumably because of damaging drought in European Russia this spring. The main crops produced in the Central District are spring wheat, rapeseed, sugar beets, tubers and pulses. Vegetables are also widely grown but would not be included in the grain harvest estimate.

European Russia Drought

The 87-90 MMT new crop estimate is way higher than last year's 61.3 MMT harvest, decimated by drought, but below the 96 MMT produced in 2009 considered to be "normal."

Yields were coming in at 2 metric tons (MT) per hectares compared to 3 MT/hectare normally. Production losses of 35% are extreme giving rise to pessimism on crop outcomes. Indeed the yields in the Black Earth area, within the Central District, are the most productive in all of Russia, typically. Harvesting was 43% finished August 9 in this area based on official Russia data.

Very severe drought occurred in the Kursk, Tambov, Penza and Voronezh districts, where rainfall accumulated from March through June was 40% of normal, or less. Some Russia grain farms near the border with Ukraine fared better, receiving upwards d to 80% of normal rainfall. Drought culminated with an intense heat wave, spurring rapid grain ripening from mid June to mid July.




Back to news


Spell Check

No comments have been posted to this News Article

Corn College TV Education Series


Get nearly 8 hours of educational video with Farm Journal's top agronomists. Produced in the field and neatly organized by topic, from spring prep to post-harvest. Order now!


Market Data provided by
Brought to you by Beyer