* Rapid corn planting progress likely this week
* Farmers sowing crop between showers
* U.S. corn seeding pace had fallen to record low
By Sam Nelson
CHICAGO, May 17 Less-than-ideal yet drier weather this week allowed U.S. farmers to begin catching up their corn planting pace that had fallen to a record low when the week began, an agricultural meteorologist said on Friday.
"They probably got quite a lot done," said Andy Karst, meteorologist for World Weather Inc. "There were only scattered showers this week, so many were able to work between showers."
Karst said scattered and light showers would continue Friday into the weekend, with heavier rainfall expected early next week, especially in the northern Midwest.
"Showers will continue next week, but they'll be light, and the last week of May should be fairly dry, so there will be good progress made," he said.
The improved crop planting weather this week allowed farmers in the fields, and very rapid progress is expected to have been made. Some observers are expecting seedings to be half or 60 percent complete by the end of this week, but still at a record slow pace.
"I'm adding 29 percent to my corn planting pace number, so that gets it up to 57 percent by this coming Monday," said analyst Mike Zuzolo of Global Commodity Analytics.
As of Sunday, farmers had seeded 28 percent of their intended corn acres, up from 12 percent a week earlier but far behind the five-year average of 65 percent, the U.S. Department of Agriculture said in a weekly report on Monday.
The planting pace for corn was the slowest for this point in the year in USDA records dating back to the 1980s, lagging 1984, when farmers had seeded 29 percent of their corn.
The figure fell below the average estimate of 29 percent from analysts' surveyed by Reuters ahead of the report.
For soybeans, the USDA said planting was 6 percent complete, up from 2 percent a week earlier. But the pace was the slowest for the 19th week since 1984, when soybeans were only 4 percent seeded. The five-year U.S. average is 24 percent.
U.S. corn yields are unlikely to reach their full potential this year as the slowest planting pace on record shortens the growing season, increasing risks that plants will pollinate under peak summer heat, agronomists said on Tuesday.
"We have taken some off of our yield potential," said Emerson Nafziger, extension agronomist at the University of Illinois. "Our preference is to have it in the ground by May 1."
Nafziger said that based on the last six years of the university's lab results for Illinois, corn planted after May 10 in the state, which ranks second in production of the crop, might see a yield loss of 6 percent. The yield losses increase to 12 percent after May 20 and 20 percent after May 31, he added.
Corn grown in the U.S. Midwest grain belt typically starts pollinating in July. Plant growth and yield potential can be reduced if plants are forced to devote energy to staying cool during the hottest days of summer.
Chicago Board of Trade corn futures were trading firm on Friday due to the slow seeding pace of the U.S. crop and related concerns about production declines due to the hampered plantings. (Additional reporting by Julie Ingwersen, Karl Plume and Michael Hirtzer in Chicago; Editing by Lisa Von Ahn)