Temperatures during the past week were near or a bit below average for most of the North Dakota Agricultural Weather Network (NDAWN) stations. Today (Thursday) will continue that trend of cool summer weather and even tomorrow (Friday) the eastern part of North Dakota into northwestern Minnesota, albeit a bit warmer, will still be recording temperatures on the cool side of average. That will all change this weekend into next week as much warmer air is expected to move into the northern plains just in time for the Independence Day weekend. Temperatures are expected to be in the 80s with 90° plus potential on some days. This warm up will be associated with the development of a trough of low pressure in the Pacific Northwest that will build a temporary ridge over North Dakota.
That trough of low pressure should shift east gradually next week and in turn, bring with it thunderstorm possibilities after July 4. In the short term, there should be some scattered thunderstorms this weekend as the warm air surges back into the region with northern North Dakota the most likely location to record some rainfall. My strong suspicion is that most of the area will see little if any moisture until after Independence Day when the just described trough swings through.
Estimated relative humidity (RH) hours are given in Figure 1. There should be a more hours with higher RH values this week than were present during the past couple of weeks as more Gulf of Mexico moisture (higher dew points) is advected into the area. The projected Growing Degree Days (GDDs), base 32°, 44° and 50° for the period June 30 through July 6, 2016 are presented in Figure 2. Base 32° is now given instead of Base 34° per several requests. You are always welcomed to contact me with requests or questions. My contact information is below.
Daryl Ritchison, Extension Meteorologist