Sunday, September 29, 2013

Update... Chili-NO-Beans Cold Front

1:45 PM Monday Update... With each new model run, forecasting the coolest air so far this season is gaining more confidence.

There's going to be a rather large temperature swing from Friday into Saturday.  Some locations may get very close to 90 Friday, then only make it into the 60s for high temperatures on Saturday and Sunday with lows in the 40s.  There could even be some 30s across far northern Arkansas.  Beyond this cold front, I noted in the original blog post that the blast of cool air will be short lived.  However, the newest run of the Euro says "not so fast my friend."  While it's too early to forecast this, it's hinting the cooler air may stick around a lot longer with a tough developing over the central and eastern United States.  This would prolong the great air mass deeper into October!

Here are a couple maps from the run of the European model this morning.

This is the Euro valid at 1PM Saturday.  The black lines are isotherms, lines of equal temperature.  Look how tightly packed they are across Arkansas.  This rapid change in temperature within a short distance indicates the presence of the cold front.  The contrast across the state is sharp.  Readings in NW Arkansas are in the 50s with 80 degree+ temperatures across the SE corner.
This is Sunday morning at 7AM.  The line running from near Mena to Little Rock up to NE Arkansas is the 50 degree line.  The Euro is telling us all the locations north of that line are in the 40s and south of it in the 50s for lows.  Better get the heater checked out!!

We always look for that first real cold front of the fall which brings enough chill to the air, many rush to the store and buy ingredients for chili. If it's real chili, it has NO beans in it, IMO

As first discussed here a few days ago, the coolest air of the season so far is scheduled to arrive late this week.  While there are timing differences between the two major models I look at, both the GFS and the Euro shows the cool air mass settling in next weekend.  While I know many of you have been awaiting this for several months, this batch of cool air will likely not last all that long.  The below average temperatures should be in and out within just a few days and we'll begin another warm up.  More on that later, let's just enjoy what we have in "front" of us!

This is the European model valid Friday at 7PM  This indicates the front is through most of the state with north and northeasterly winds ushering in very cool air.  See those black lines circling the low over the Great Lakes?  Those are "isobars", lines of equal barometric pressure. With the counterclockwise circulation of air around and into the low at the surface, the air BEHIND the front is very dry and cool.  A round of showers and storms could accompany the front as it marches through the state.
The 18Z Sunday run of the GFS model shows a little slower scenario.  This brings the front through Arkansas Saturday morning.  However, no matter which model you look at, both show the colder air making a visit into Arkansas.  But how cold?
You're going to need to click on this to make it larger. I know these numbers are tough to read.  This is the European model valid at 7AM next Sunday morning.  This shows you the lowest temperature between 1AM and 7AM.  Lows that morning are in the 40s statewide and I would not be surprised to see some 30s across some of the coolest locations over the north.
And the Euro valid at 7PM Saturday shows you the expected daytime highs.  Most of the state, according to this, should ONLY reach the 60s for highs Saturday afternoon.  This is several days away and will likely change, but this is entirely possible.  Thanks to for the 2 maps above.  Great site for model data!!!!
In summary, stay tuned.  IF all this comes together, it's chili time!  Those leaves will be changing soon!


lana chumley said...

I am ready for Fall colors, cool nights, and an end to summer!

Brandon Ryan said...

Your prediction was a little off. The cold front that came to my house had beans.

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