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Weather Forecast (07/12/18)

The July 12 through July 18, 2018 Weather Summary and Outlook

As Yogi Berra once said, “It’s deja vu all over again.” In other words, it was yet another week with temperature averaging above normal. A few North Dakota Agricultural Weather Network (NDAWN) stations were near average, but generally, in much of the region the temperatures were two to four degrees above normal (see Figure 1).


Although there were no widespread rain events, there were enough regional thunderstorms clusters that nearly all NDAWN stations recorded some rain in the past seven days. The graphic below does not include the rain from early Wednesday morning that impacted areas in northern North Dakota into far northwestern Minnesota.


Since the start of meteorological summer on June 1, most NDAWN stations have recorded average or above average precipitation (Figure 3). The most pronounced areas with rainfall deficits in the past six weeks are the central Red River Valley areas in both North Dakota and Minnesota as well as extreme northwestern Minnesota.

The persistent above average temperatures that have been recorded since the beginning of May will continue for the next seven days, although, a brief period of below average temperatures are predicted to occur for a few days next week. Projected growing degree days (GDDs) Base 32°, 44° and 50° for the period of July 12 through July 18 are presented in Figure 4.


With some rainfall expected in the next seven days, plus several days with high dew points, the projected hours with relative humidity above 85% may exceed 40 hours over much of eastern North Dakota (Figure 5). Some drier air is expected early next week (with the cooler temperatures mentioned), meaning the highest disease risk looks to be through Sunday.


Using May 5 as a planting date, the accumulated wheat growing degree days (Based 32°) through July 10, 2018 are presented in Figure 6. Use this link to find your exact GDDs for your planting date(s).


Using May 10 as a planting date, the corn accumulated growing degree days (Base 50°) through July 10, 2018 are presented in Figure 7. Use this link to find your exact GDDs for your planting date(s).



Daryl Ritchison


Interim Director of the North Dakota Agricultural Weather Network



This site is supported in part by the Crop Protection and Pest Management Program [grant no. 2017-70006-27144/accession 1013592] from the USDA National Institute of Food and Agriculture. Any opinions, findings, conclusions, or recommendations expressed are those of the website author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture.

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