* Narrow window to plant corn early next week
* Top producers Iowa and Illinois slowed by rain
* US corn planting pace at record low
By Sam Nelson
CHICAGO, May 3 Wet and chilly weather into the weekend will continue to slow plantings of the U.S. corn crop that already has fallen to the slowest seeding pace on record, an agricultural meteorologist said on Friday.
"Rains will occur into the weekend in the central Midwest and northeastern Delta, shifting into the southeast early next week," said Joel Widenor, meteorologist for Commodity Weather Group (CWG).
Drier and warmer weather is expected early next week giving some farmers a narrow window of opportunity to plant corn but showers are expected again later next week, Widenor said.
The best opportunities to plant corn will be in the eastern Midwest with the most notable struggles in the western states, including top producers Iowa and Illinois, according to CWG.
Rain around the U.S. Midwest kept farmers out of fields last week, matching the slowest corn planting pace ever, government data released on Monday showed.
The weather also took a toll on the developing winter wheat crop, which deteriorated to its worst condition for this time of year in 17 years.
The U.S. Department of Agriculture said corn planting as of April 28 was 5 percent complete, just 1 percentage point ahead of where farmers were a week ago. The pace was the slowest since 1984, when farmers also had completed just 5 percent of their corn planting.
The USDA's weekly crop progress report showed the 5 percent corn planting completion pace as of Sunday was a huge drop from 49 percent a year earlier and down sharply from the 31 percent five-year average seeding pace.
Analysts had predicted corn planting to be 9 percent finished, according to the average of 13 estimates in a Reuters poll that ranged from 7 percent to 11 percent.
Chicago Board of Trade corn futures were trading higher on Friday, boosted by concerns of production losses due to late corn seedings. (Additional reporting by Mark Weinraub in Chicago; Editing by Chizu Nomiyama)