A deep freeze early this week likely harmed some of the U.S. Plains hard red winter wheat crop that was in the jointing stage of development, adding to the woes of a lingering drought, an agricultural meteorologist said on Tuesday.

"It (freeze) was well within the parameters of damage in southwest Kansas, the west Oklahoma Panhandle, far northwest Texas and southeast Colorado," said Don Keeney, meteorologist for MDA Weather Services.

Early morning temperatures for the past three days fell into the single digits (degrees Fahrenheit) and teens in those areas, Keeney said, and remained that low for six or seven hours.

"For damage to occur to jointing wheat, temperatures would need to fall below 24 F for three or four hours, and we certainly saw that," he said.

The low early Tuesday in Gage, Oklahoma in the heart of wheat country was 15 degrees F and the low tomorrow morning will be warming up to 32 F, Keeney said. "This is it for the real cold weather, it should be 10 to 15 degrees warmer tomorrow," he said.

Keeney said the low temperature early Tuesday fell to 10 degrees F in southeast Colorado, a geographic area that likely would be comparable to Oklahoma for the growth stage of the wheat plants.

The U.S. Department of Agricuture's (USDA) weekly Oklahoma crop progress report released on Monday showed 41 percent of the winter wheat crop was in the jointing stage of development. Wheat plants in the Texas Panhandle likely are advanced beyond that percentage and the crop in southwest Kansas is jointing as well.

Travis Miller, an agronomist at Texas A&M University, told Reuters late on Monday that the state "did not dodge a bullet. It is a mess out there, both from freeze and drought."

Commodity Weather Group (CWG) on Tuesday said only "spotty" damage is expected to jointing wheat in the Southern Plains and emergent corn in eastern Texas from the lows in the 20s F this morning.

"Recent rains have benefitted about two-thirds of the Plains wheat and the southwestern third will remain at risk for building dryness next month as jointing and early heading occur," said CWG meteorologist Joel Widenor.

Wheat fields in key growing areas of Texas have been two to three weeks ahead of normal maturity due to recent beneficial moisture and warm conditions before the freeze that descended on the Plains over the weekend.

Much of the new winter wheat crop in the U.S. Plains has been struggling due to extended drought, making the young plants vulnerable to wild weather fluctuations. Recent snow and rain have improved conditions, but the crop generally is still seen as likely to have much-shortened production potential.

"Wheat is a wreck looking for a place to happen," Miller said.

The Texas Agricultural Statistics Service on Monday afternoon said that the Texas winter wheat crop was rated 47 percent poor to very poor due to the drought, 34 percent fair and 19 percent good to excellent.

Kansas wheat was rated 31 percent poor to very poor, with 40 percent fair and 29 percent good to excellent. The Oklahoma crop was rated 33 percent poor to very poor, 41 percent fair and 26 percent good to excellent, according to state agricultural officials. (Additional reporting by Carey Gillam in Kansas City; Editing by Chizu Nomiyama)