Weather Forecast (07/29/21)
This past week was another period with well above average temperatures (Figure 1). Most of the region recorded temperatures anywhere from 3° to 6° above average. There were pockets of even warmer temperatures in localized areas. These next 7 days look to be noticably cooler with some locations even recording a high in the 70s on a day or two. Overall, mainly low to mid 80s expected during this forecasting period. In other words, a period of near average temperatures, although, there are signs that well above average temperatures may return in the 6-10 day period just beyond this forecasting period. I have a feeling that there will be at least a couple of periods of thunderstorms in the next week, but odds favor more missing than hitting which will mean yet another week with many areas struggling with a lack of adequate moisture.
This past week the main rains were across southern North Dakota into west central Minnesota. Most northern areas recorded little or no precipitation in the past week (Figure 2).
Several of you requested that I post rainfall departures from average this growing season. Figure 3 has the departures from average rainfall from May 1 through July 27.
The projected growing degree days (GDDs) base 50°, 44° and 32° for the period of July 29 through August 4, 2021 can be found in Figure 4. With temperatures near or slightly above average these next 7 days, GDDs will be lower than what was recorded in the past few weeks.
Using May 1 as a planting date, the accumulated growing degree days for wheat (base temperature 32°) is given in Figure 5. You can calculate wheat growing degree days based on your exact planting date(s) here: https://ndawn.ndsu.nodak.edu/wheat-growing-degree-days.html
Using May 10 as a planting date, the accumulated growing degree days for corn (base temperature 50°) is given in Figure 6. You can calculate corn growing degree days based on your exact planting date(s) here: https://ndawn.ndsu.nodak.edu/corn-growing-degree-days.html
Soybeans also use base 50° like corn, but NDAWN has a special tool for soybeans that, based on your planting date and cultivar, can estimate maturity dates based on average temperatures, as well as give you GDDs based on your planting date(s) you set. That tool can be found here: https://ndawn.ndsu.nodak.edu/soybean-growing-degree-days.html
Director of the North Dakota Agricultural Weather Network (NDAWN)