* Warm-up next week to melt snowcover
* Cold snap later in the week eyed
* Minimal improvement seen for river water levels
By Sam Nelson
CHICAGO, Jan 4 (Reuters) - Threats of winterkill to the drought-stricken U.S. hard red winter wheat crop grown in the U.S. Great Plains is currently minimal but forecasts for a cold snap next week need to be monitored, meteorologists said on Friday.
"Colder air does arrive in the Plains and western Midwest around mid-month, but winterkill threats are still low," said Joel Widenor, meteorologist for Commodity Weather Group.
A blanket of insulating snow currently covers much of the Plains wheat crop that struggled to become established during fall seeding because of extremely dry soils amid the worst drought in over 50 years.
"Drought relief to the west will remain limited," Widenor said.
Dry weather is expected in most of the U.S. grain producing areas through the weekend followed by rain and some snow early next week in the Plains states of Oklahoma and eastern Kansas, according to Andy Karst, meteorologist for World Weather Inc.
"The weather forecast is all over the map but this morning it looks like 0.20 inch to 0.60 inch of precipitation with the heaviest amount in Oklahoma," he said.
Karst said warmer weather next week would melt most of the snowcover in the U.S. Central Plains hard red winter wheat region, leaving the crop exposed to potential winterkill.
"Colder weather is expected beginning late next week so that will need to be watched for possible winterkill," Karst said. Karst said the melting snow next week would lead to only minimal improvement in water levels in the Mississippi River.
Widenor said showers expected to spread from the Southern Plains into the southern and eastern Midwest and Delta by the middle of next week would offer up some improvement in moisture for mainly Texas and Oklahoma.
"While a major turnaround in river levels is not expected, the showers may help to temporarily slow further declines (of water levels) in the mid-Mississippi Valley," Widenor said.
Snowfall in parts of the U.S. Plains last week had little impact on historic drought gripping the region, but parts of Illinois, Wisconsin and the Southeast showed slight improvement, weather experts said.
A weekly report issued Thursday by a consortium of federal and state climatology experts said that as of Jan. 1, 42.05 percent of the contiguous United States was in severe to exceptional drought, down from 42.45 percent the previous week.
(Additional reporting by Julie Ingwersen in Chicago; Editing by Nick Zieminski)