Update - 09/30/2015

See the previous post by clicking here.  In that post I discussed the cool down, especially later this week and had a question about a freeze across parts of the corn belt.  I'll address that at the end of this blog post.

In that previous submission I did Sunday, there was a map of potential rainfall through the week.  The first system did bring scattered showers and a few thunderstorms to the central part of the country but most areas remained dry.  Most of the precipitation fell in narrow bands.  In fact here locally, the airport rain gauge received 0.13" of rain while just 1 1/2 miles northeast had nearly an inch.  So it goes with "convection".

During this past year I have mentioned a cycling pattern that set up in the fall.  This pattern that persisted into late summer has now definitely shown signs of breaking down.  The transition from the old to the new will be very challenging for forecasters and computer forecast models will have many difficulties in the output of solutions.  Take for instance Hurricane Joaquin that is currently spinning away near the Bahamas (see the satellite image below).  As of Wednesday afternoon it was moving slowly southwest but at some point the computer models turn it and take it in varying directions.

The following map shows some of the possibilities based on all different kinds of computer model solutions and initial input.  If you were a forecaster, where would YOU say it will track? (click for a larger version)

What will complicate this forecast is that another system (the X on the satellite image below) currently moving southeast through the Midwest will amplify and intensify into a strong upper storm.  Will it ingest Hurricane Joaquin?  If it does, it would be a similar event as Hurricane Sandy was back in the fall of 2012.

The satellite image shows both Joaquin and the disturbance over western  Iowa.

One of the computer models has the following solution...

So does any of what is happening on the east coast matter to the high plains?  Yes, it does at least indirectly.  First the disturbance amplifying into the southeast will help draw colder air into the midwest and eventually force gulf moisture back up through west Texas on the backside of the colder airmass. The unknown path of the hurricane and IF it merges with the upper system will likely block the flow aloft.  This could cause an upper low to dig into the western U.S. or Rockies (other reasons why this might happen) and would provide a boundary across the plains for a source of lift for more plains precipitation.  The latest 7 day precipitation outlook from the Weather Prediction Center follows:

The colder airmass following the intensifying upper low may not have quite enough to get a widespread freeze across the corn belt but it will be pretty chilly.


If you missed the post on the fall/winter/spring outlook, it can be found here