Thursday, October 19, 2017

NOAA Winter Guidance

NOAA released their winter guidance today and before all of you snow lovers panic, let me try to be the voice of reason.

They break their outlook down into 3 categories: cooler than average, warmer than average, and equal chances.  The "equal chances" can be explained to me all day long and I'll still never understand.  Basically, IMO, they area saying that they just don't know with the available information.

They are calling a good chance for above average temperatures.  What is going to be?  1° above average or 4,5,6?  There's a huge difference.  Which is it?

They are calling for equal chances for above, below, and average precip. What about snow?

It's important to read the fine print in these forecasts as well.

"Other factors that influence winter weather include the Arctic Oscillation, which influences the number of arctic air masses that penetrate into the South and is difficult to predict more than one to two weeks in advance, and the Madden-Julian Oscillation, which can affect the number of heavy rain events along the West Coast."

Here's an example of what can happen.  I'M NOT SAYING IT WILL HAPPEN.  Look no further than December of 2012.  It was a VERY WARM month.  Look at all those highs in the 60s and 70s.  Temperatures were 5 degrees ABOVE average.  That's outrageous for any month.  HOWEVER, we all remember what happened on Christmas and the day following.  10-15 inches of snow and more than 250K lost electricity.  Some lost it for more than a week.

Again, I'm not saying December 2012 is going to happen, but I'm using it as a tool to explain how things happen in the weather.  While the winter as a whole could be close to average or even above average in terms of temperatures, 1 or 2 impactful events can change your entire perception

Hope I make sense and this helps out.

Tuesday, October 17, 2017

First Frost, First Freeze, Average Snow, Average 1st Snow

All of this data is based upon the standard 30 year average and courtesy of NOAA.

I thought this would be helpful to many of you.  Enjoy

Friday, October 13, 2017

Long Range Cold

I think warm weather fans are kinda getting tired of it too!  We'll probably fall just short of a daily record high in Little Rock Saturday.  That record is 93° set just a couple years ago in 2015.  At this time, I think we'll have a shot at 89 or 90°.  A strong cold front will move in Saturday night and Sunday with a few showers, but nothing heavy.   There's a chance some places don't see any rainfall at all.  Most of it will fall during the first half of the day as well.

Next week will be cooler, BUT there's a chance even cooler air arrives for the end of the month.  Many years ago, meteorologist Joe Bastardi with taught me the typhoon recurvature theory.  When you have a typhoon in the far western Pacific recurve to the north and then the northeast, it typically produces a trough in the central and eastern United States 6-10 days later.  Lo and behold, the models are forecasting that to occur.  So, if the theory holds true, the last week of the month should deliver a shot of cold air.  The models are now starting to indicate this.

The GEFS ensemble run last night does show the cooling in the long range.  In the 11-16 day time period (Oct 24th - Oct 29th), temperature anomalies in degrees C are around -1 to -3°.  Remember, this is over a 6 day period of time.  It does show the cooling and the chance for below average temperatures over the areas the trough should be situated at that time. The averages at this time are around 70° so it's POSSIBLE we could have highs in the 50s and 60s at some point towards the end of the month.  Under the right conditions, overnight lows could be cold enough to support our first frost and that would be typical according to climatology.  It will be interesting to watch NOAA and their 8-14 day outlook.  Those are manually drawn and NOT computer generated.  At this time, they indicate nothing but a high chance for above average temperatures.  Let's watch and see if it flips within the coming days. 

NOAA Winter Guidance