Climatologically, the middle of July brings the warmest period of the year for the state. This week that climatology is being borne out with heat advisories over parts of the state because of excessive heat and humidity, said Dennis Todey, SDSU Extension climatologist.
“With the extreme heat, comes additional stress for crops and cattle to handle, as well as additional water use requirements,” he said.
Despite the recent dryness in some areas, crop conditions have held steady or improved over the last several weeks. However, because of the early season wet and cool conditions, crops are delayed in development. Only 6 percent of corn is tasseling compared to the five-year average of 9 percent.
Todey said that at this point the situation is not a huge concern, but bears watching during the rest of the season.
“The main issue could arise later, as delayed development goes into the fall season, where the timing of a hard freeze could impact yield at harvest,” Todey said.
From a precipitation perspective, Todey said the last month has proved interesting across the state.
“Conditions generally have dried over the state, slowing additional drought recovery. In some locations precipitation has been notably low,” he said, pointing out that Milesville in Haakon County had its fifth driest on record from mid-June to mid-July with only 0.33 inches of precipitation; and during the same timeframe, Martin has been second driest.
Todey noted that other climate stations in south central South Dakota ranked as the top 10 driest. In contrast, he said, over the last 30 days several northeast stations have received as much as 8.18 inches, recorded at the Clear Lake station.
“Several other stations from Bryant to Webster have also been ranked as the top 10 wettest counties. Some notable wet locations west of the Missouri River include Murdo in Jones County and Ludlow in Harding County, both of which have been in the top five wettest,” Todey said.
Laura Edwards, SDSU Extension climate field specialist, added that these numbers indicate the extreme variability, as well as winners and losers so far this year with precipitation.
“The fortunate aspect is, unlike last year, the dry areas have followed a relatively wet spring easing some of the impact of the dryness,” Edwards said “While conditions have been similarly dry to last year in a few places, the wetter spring has alleviated major issues so far. Temperatures overall have been fairly moderate over most crop areas limiting additional dryness problems.”
New outlooks from NOAA’s Climate Prediction Center for August and the August-October period, Todey said indicate no strong trends in temperature or precipitation.
“There have been no consistent patterns showing up in the climate computer models to this point. Climatologically, by late July, precipitation chances fall off while temperatures increase. This is consistent with what we have experienced this year. But there are still some chances for precipitation coming through the end of the month over most of the state,” Todey said.
Edwards said in the near future we are not likely to see any further drought improvement in the drought-covered areas of the southwest.
“With warm temperatures and limited chances for precipitation in that region for the next one to three months, there is little opportunity to make conditions better. For now, we hope that conditions hold steady,” Edwards said.
Most of the cropping areas in East River are currently drought free; but she said some dry soils do exist.
“Two dry weeks could introduce issues quickly especially during the reproductive period of corn occurring now,” Edwards said. “The high water crop water demands can dry soils quickly without additional precipitation. Thus, some additional timely rains will be needed to ensure continued good growing conditions.”