80s in October: A Look at the COMMON Occurrence

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It's like clock work - throw in a period of above normal temperatures and the questions start flying. These questions range from "where's Fall?" to " Will we actually get cooler weather?" to my favorite, "Is this because of Global Warming?" I think it's important to first take a step back and realize that just because the calendar says it's Fall, it doesn't mean we flip a switch and all of a sudden the summer pattern that took a long period of time to form, just falls apart. The sun angle is still decently high and we've got soupy air still flowing north out of the Gulf. We WILL cool down, it's just a matter of time. The issue so far for this month, or I should really say for the first half of the month, is the southeast ridge. Admittedly I thought it would break down much quicker when I looked at the pattern setup a couple weeks back. Obviously that is not going to be the case. This is a STRONG system. Take a look at it for yourselves. Below you'll see a snapshot of what the atmosphere is doing at the 500mb level. See the orangy color? That's indicative of higher than normal pressures which when positioned to our south equates to warmer than normal temperatures. Below the 500mb chart you'll see a temperature anomaly which is just showing the departure from normal. 

Looking at the second map one could get scared. It looks like someone took a flame thrower and is scorching the entire east coast. This is what 10+ degrees above the norm looks like. But at the same token, Mother Nature likes to balance things out, look how COLD it is for 60% of the country. You can't just look at one area and proclaim "Global Warming is making it hot!". Look at the BIG PICTURE. It's called weather. It changes. 

Now take a look at the 500mb pattern for mid October. See the difference? All the significant ridging is gone. Now, mind you the farther we go out the more washed out the colors become and I fully expect there to be a trough that is a bit more pronounced in the east. Look out west. See those lines? They are lifting to the north which would indicate some ridging in the WEST. Now, let's look at the surface temperature anomaly... Yup. There it is. Cooler temps. I've got no doubt that once that ridge breaks down, we will see cooler temps. The second half of the month will certainly be cooler. The average for the entire month may be skewed a bit because of a very warm front half though. 

A good indicator of how things will play out is looking at our Sea Surface Temps... I brought this up in a blog I wrote earlier in the week. Believe it or not what goes on in the Indian Ocean can hint at what's coming down the pipeline. See the cooler than average water temps just west of Australia? That has everything to do with what ultimately happens with the Madden Julian Oscillation (MJO). When you've got cool water you typically inhibit convection so thunderstorm activity is much less. The Southern Oscillation Index (SOI) is also tanking which is a good indication that an El Nino is coming on. As I explained in that same blog earlier in the week, this won't be your typical El Nino - it will be Central Pacific based which paints a different type of late Fall and Winter forecast for our region. 

Let's get back to the MJO real quick so I can show you what's going on with it. It's currently in Phase 1.

That promotes WARMER than average weather along the east coast, as you can see here: 

Put the MJO in Phase 1 in December and the outcome is completely different: 

What I'm trying to get at here guys is that forecasting mid to long range is a COMPLETELY different animal than trying to nail down the 7 day. There are different variables at play and it's almost like a gigantic puzzle. Just because something is happening right now and looks to continue for a little while does NOT mean it will stick around forever. I am very confident in my idea that we will see an overall colder and snowier Winter than last year, I am also very confident that we WILL get in on fall-weather. It's just not going to happen overnight. 

On another note I don't think we are completely done with the tropics just yet. I think it's possible we get development in the Gulf and or near the Bahamas in the 10-15 day period. This theory is supported by the ridge in the east. Just a hunch but I wouldn't be surprised in the least if we did see something form and try to wreak havoc!  

Here's a look at some numbers for you. Number of 80s in October by the year from 2000 to 2017:

2000 - 3

2001 - 4

2002 - 4

2003 - 0

2004 - 0 

2005 - 0

2006- 2

2007 - 7

2008 - 2

2009 - 0 

2010 - 1

2011 - 2

2012 - 2

2013 - 6

2014 - 0

2015 - 1

2016 - 4

2017 - 5

And number of 80s by the DECADE dating back to the 1940s... Nothing abnormal here. I think the way it's reported by most media outlets is the only concerning aspect here. 

1950s - 26

1960s -21

1970s - 9

1980s - 18

1990s - 23

2000s - 22

2010s - 21

Avg. 20 per decade... Most in 1990 (8) Least in 2014 (0)