According to the National Weather Service in Hastings the Central Plains are being affected by the Madden-Julian Oscillation, MJO. Tropical rainfall exhibits strong variability on time scales shorter than seasonal El Nino. These locations in tropical rain fall often go through an entire cycle in 30-60 days. These oscillations are naturally occurring and have a significant impact on the wintertime jet stream and atmospheric circulation over the North Pacific and western North America.
The result of the MJO currently is warmer weather here in the Central Plains. The MJO is currently going through phase four and moving into five. This means low pressure is moving through the desert southwest. The point is that there is no cold air in sight for at least the next two weeks. According to the NWS this is understandable as temperatures were colder than normal during October and November.
Aloft in the atmosphere, a trough, an elongated area of low pressure, will move onshore in the west and will cause heights to rise and result in a deep trough from North Dakota to Texas. This will increase northwest flow as it moves west. Moving in to take its place will be a ridge, an area of high atmospheric pressure, but that will quickly deamplify as a shortwave trough crosses the Northern Rockies.
What this means at the surface is that the NWS Hastings County Warning Area will see low pressure head across Canada and send a cool front that will cross the area on Wednesday. High pressure will emerge from the Western states but quickly be replaced by low pressure which will induce a warm front. After one last blast of low pressure, high pressure will begin to build over the weekend.
Over the week temperatures should be 10-15 degrees above normal, with lows above 7-15 degrees above normal. Wednesday and Thursday will windy with breezy conditions.
The pattern will remain basically dry, with any precipitation being in the form of rain. The best chances for a slight chance of rain will be Wednesday; the next chance is Saturday night. However, any precipitation that falls will be light.
While details are still hard to pin down this far out, anyone hoping for a white Christmas should be ready to be disappointed. Dry weather seems to be prevalent throughout these next few weeks.