Good morning Weather2020 bloggers,

The weather pattern will go through some major changes in the next five days. Right now the United States is mostly in west to east flow aloft, what we call zonal flow aloft. By the end of the week a big dip in the flow will develop over the western states. Let’s take a look:

2On this first map there continues to be strong hints and indications of a positive Arctic Oscillation and a positive North Atlantic Oscillation. Here’s how you can tell. As you look at the flow aloft, the map to the left which shows the flow at around 18,000 feet above us or the 500 mb level, you can see one stream of flow across the Pacific Ocean going over a ridge off the California coast.  And, then there is a little dip approaching the Missouri River Valley, and another system just off the northeastern coast. More importantly, take a look at the northern stream across far northern Canada. There is little obstruction to the flow, thus no blocking, and this is indicative of the AO and NAO positive indexes.

By the end of the week, that disturbing northern stream continues, but look at what is coming back.  A big dip in the flow over the southwestern states. This is something we must monitor closely. This next map is valid Friday night at midnight:

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Now, I am sure many of you are going to jump from conclusion to conclusion as these changes are modeled by the computer models. I suggest just monitoring these models and let’s wait before we make any conclusions on whether it will snow or now, where the best chance of snow will be located or not, etc.  Just last night the European model and the GFS model had very different solutions for this weekend and next week. The European Model had snow near KC where the GFS had it yesterday, but then the overnight GFS had no snow. Let’s give it two or three more days as the models are not handling this change very well at all.  Using the LRC, this first storm is doing beginning to look more like it should, and the second storm was lost by the GFS model last night, so it was likely just way off.

Right now, it appears the warm pattern will be continuing with a lack of any major Arctic air blasts showing up. Some Arctic air is building, and some blocking has been modeled in around seven to fourteen days. Let’s see how this develops.

Have a great day, and we will look deeper into these developments in tomorrow’s blog. Take a look at my dogs at sunrise this morning. This is Breezy, the big one, and Sunny, my 8 month old.

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Gary