Good morning bloggers,
Did you see the “spider weather cast” from last night? Here is the link:
Today will be day five, and the last day of the heat wave. We are expecting another high temperature in the middle 90s with a weak cold front approaching the area which will bring us a chance of a few showers and thunderstorms later tonight into Thursday. A major change in the weather pattern is showing up in a few ways. Before we begin this discussion, let’s take a look at what I put in yesterday’s blog entry:
September Rainfall by year (Last 10 years)
- 2013: 0.81″ (September 1st, an inch fell downtown, but only 0.26″ fell in Overland Park)
- 2012: 2.89″
- 2011: 1.14″
- 2010: 7.58″
- 2009: 2.02″
- 2008: 9.82″
- 2007: 2.47″
- 2006: 2.22″
- 2005: 3.61″
- 2004: 3.48″
- 2003: 2.61″
- September average rainfall: 4.62″
- Average last 10 years: 3,78″
The 0.81″ of rain that has fallen this month came just as September began two Sunday’s ago. We are still waiting for our next significant chance of rain, but many chances are now showing up and confidence is growing that we will have a few days with rain and thunderstorms during next two weeks. Let’s take a look at the beginning of the change:
Fall is rapidly approaching and the jet stream is finally strengthening. The jet stream is created by temperature contrast and as colder air masses begin forming way up to the north over northern Canada and Alaska and across Siberia and near the North Pole, huge temperatures gradients will begin developing in the next two to three weeks and the seasons will change. Colder air will be forced south and storm systems will begin getting stronger. We are still in the final stages of last years weather pattern, but as the jet stream drops south a new weather pattern will blast last year’s weather pattern into history and we will finally have something very new developing. Yes, the new LRC 2013-2014 is about to begin evolving. We will have to be patient, however, because it doesn’t happen instantly, but rather it develops over a period of weeks from later this month into November.
The 500 mp forecast map above shows, what looks to me to be just a gradual strengthening of the old pattern, but still the very beginning of something new. I am hoping that the subtle differences that I see could help set us up into a slightly better chance of heavier rainfall, and that first good chance shows up around Sunday, hopefully after the Chiefs/Cowboys game. Here is a surface forecast map valid at 1 AM Monday morning (Sunday Night):
A weak cold front will drift through us Thursday, and then it will be in the area Friday through Monday. On Friday, drier air will take over allowing for some great weather Friday into Saturday. By Sunday, the cold front will have stalled and it should bend back to the north in response to a strengthening Pacific Jet Stream that will move out over the western states. And, a series of weak disturbances will be approaching over the weekend as well. The chance of thunderstorms will increase Sunday into Monday, but then there are many other chances showing up in the next seven to ten days after Monday. Here is one rainfall forecast that came out overnight from the GFS model. Hopefully we can get some wet systems in here before we lose the summertime humidity. It is much harder to be wet in October and November, but a new pattern will be setting up and there is a lot of hope that it sets up wetter than the past two years.
Thank you for spending a few minutes sharing in Kansas City’s increasingly exciting weather pattern. Let us know if you have any questions or comments and have a great Wednesday!