The May 28 through June 3 weather forecast:
The next 7 days is expected to bring extremes in temperatures with precipitation projected to occur during three time frames. The first of these is the rain that is moving through the region today (Thursday). This is associated with an area of low pressure coming out of the northern Rockies with rainfall amounts near or under 0.50 inches in most locations. As this storm moves into Ontario tonight it will pull down some very cool air for the time of year. Tomorrow (Friday) should be windy (NW) with steady or perhaps even falling temperatures as an area of high pressure with origins in the Arctic moves south.
That high pressure is expected to bring a light wind, clear sky and temperatures cool enough for possible frost in some portions of North Dakota on Saturday morning. The highest threat for temperatures near or below 36° (when frost may form near the ground) at this time appear to be across the north central, northeastern and near the James River Valley areas of the state. Those would be the locations with the lightest wind and best radiative cooling potential. Although remaining cool Saturday afternoon, a surge of much warmer air will move back into the region on Sunday, meaning no frost concerns for that morning, but that warmer air (warm front) will probably trigger off some showers on Sunday (generally light) for the second round of rain in the next week.
The final threat of rain, likely in the form of thunderstorms will come next Tuesday/Wednesday (June 2/3) as a strong low pressure center moves across the northern plains. Ahead of that low, some very warm air will advect north with two days where maximums in the 80s are foreseen in most parts the state. Meaning from a frost threat for some on Saturday to well into the 80s early next week. With more heat and moisture available, the thunderstorms projected next Tuesday and/or Wednesday would in turn have the potential to produce localized 1 inch plus rainfall, the heaviest of the next 7 days. After that thunderstorm risk, a cool down to average or below average temperatures in the June 4 through June 6 timeframe looks probable.
Projected growing degree days (GDDs), base 34°, 44° and 50° for the period May 28 through June 3, 2015 are presented below. A high percentage of these GDDs will be accumulated June 1 through June 3.
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