KANSAS CITY — Weekend rains initiated a harvest pause in central and eastern Kansas June 19-21 after two weeks of hot, dry weather afforded a strong start to harvest in the nation’s top winter wheat production state.

About a third of the state was nearly completed when precipitation hit, providing a cooldown period that kept high temperatures and strong winds from potentially lowering test weights in wheat ready to harvest. Rain was beneficial to later-planted fields where the crop still was in the latter stages of development, such as northern areas of Kansas, as well as in Nebraska, South Dakota and Montana.

The US Department of Agriculture, in its weekly update to crop progress and conditions, said harvest completion by June 21 was 25% in Kansas (compared with 4% a year ago, 24% as the recent five-year average for the date), 85% in Oklahoma (35%, 65%), 85% in Texas (53%, 66%) and 7% in Colorado (0%, 1%).

Wheat harvest through Kansas thus far did not advance as expected. Numerous factors had harvesters scouting fields to check for readiness, rather than moving north from field to field. Whether or not a field was ready to be cut depended on which variety was planted and when, as well as timing of fungicide treatments.

At the same time, two freeze events in April impacted fields differently based on development stage. Come harvest, some fields where plants’ primary tillers were killed by freezing often had secondary tillers coming up that needed another week to go from green to brown and dry off enough to collect.

There was also a big temperature and moisture differential between north-central and south-central Kansas, with the former staying cooler and dryer, Justin Gilpin, chief executive officer of Kansas Wheat, said in a weekly update.

“There was more than three weeks’ difference in development between Republic and Sumner counties,” Mr. Gilpin said, noting by example the crop “jointing in Republic the same day it was heading in Sumner. It’s the biggest developmental difference we’ve seen in a long time.”

Yields and quality in south central Kansas were as expected based on central Oklahoma conditions and testing. Harvest moved at a rapid pace in southwest Kansas, where there were fewer acres to combine. Drought stress last fall meant only 30% to 40% of planted acres emerged before dormancy. Continued drought conditions during key spring development phases led to widespread abandonment and numerous acres earlier were zeroed out by insurance adjusters. Yields in the stressed region thus far have been lower, as expected, but wheat quality was encouraging, traders said.

Plains Grains, Inc., on June 19 released its first results from the 2020 hard red winter wheat crop with 42 of an expected 500 samples tested. PGI said the average protein was 11.1%, average thousand kernel weight was 33 grams, average grade was No. 1 hard red winter and test weight was averaging 62.7 lbs per bu.

 “Hot, dry and windy weather dominated the weather pattern in the central and northern areas of the US where the crop is still anywhere from a few days to weeks from harvest,” PGI said at that time. “Drought continues to worsen in those same areas and is negatively affecting wheat in the final stages of development and will likely affect the final yield and quality in those areas.”

The USDA’s latest assessment of the winter wheat crop’s condition indicated improvement in the northern Plains where the crop was in the later developmental stages, and a decline in the southern Plains, parts of which had wheat growing in drought conditions. Overall, conditions of the hard red winter crop were holding steady, with beneficial rains soaking some lower production states in the Pacific Northwest.

The USDA pegged good-to-excellent ratings in principal hard winter wheat states with 50% or more left to harvest in the week ended June 21 at 42% in Kansas (45% a week earlier), 29% in Colorado (31%), 62% in Nebraska (43%), 80% in South Dakota (77%) and 85% in Montana (82%).

Harvest continued unabated in dry southwest Kansas after the recent rain event mostly skirted the region. Parts of Stanton County, Kan., along the Colorado border, received a mere 1½ inches of rain since June 2019, and the other five counties in the southwest corner of the state were similarly short on moisture, as are their counterparts in southeast Colorado and the Oklahoma panhandle.

Western areas of Stanton County, Kan., were expected to wrap up a 10-day harvest period by June 27 in the absence of rain disruption, Kansas Wheat said in its Day 7 Harvest Report.

Matt Overturf from Skyland Grain in Johnson, Kan., said acreage in the area was down 15% to 20% from 2019. With dryland yields ranging thus far from 15 to 30 bus an acre and irrigated fields from 45 to 50 bus, the grain company was expecting only a third of the bus received in 2019.

Fall crops also are struggling in the absence of healthy soil moisture profiles, leading Mr. Overturf to suggest an increase in seeded wheat acres was possible this fall.

“If Mother Nature gives us a little help, we can grow a good crop,” he told Kansas Wheat.

One county north along the border with Colorado sits Hamilton County, where yields have varied widely, some as low as 5 bus an acre, though the average looked to be closer to 30 bus, grower Jason Ochs of Syracuse, Kan., told Kansas Wheat.

“Where the rains didn’t hit, yields won’t be as good,” he said, predicting the crop will be about half of last year’s, which was a record-high for the county.

But test weights there averaged about 60 lbs per bu, and proteins were testing around the mid-11% range, higher than the initial cuts in south-central Kansas. Harvest was expected to wrap June 28 in Hamilton County, where Mr. Ochs estimated 70% of wheat seeded was hard red and 30% was hard white winter varieties, such as the Kansas Wheat Alliance variety Joe.

Meanwhile, the soft winter wheat harvest continued to move north and east from the Gulf. The USDA indicated harvest completion in principal production states by June 21 was 41% in Missouri, which compared with 16% a year ago, 41% as the 2015-19 average for the date), 26% in Illinois (12%, 37%) and 13% in Indiana (8%, 16%).

In lower production states, completion was 93% in Louisiana (94% as the average),  79% in Arkansas (84%), 66% in Mississippi (86%), 76% in Alabama (87%), 93% in Georgia (95%), 70% in South Carolina (84%), 52% in North Carolina (56%), 62% in Tennessee (68%) and 55% in Kentucky (57%)

USDA good-to-excellent crop ratings by June 21 in the principal soft wheat growing states were 45% in Missouri (39%), 65% in Illinois (60%), 63% in Indiana (66%), 64% in Ohio (71%) and 61% in Michigan (65%).