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EPO data


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Thanks, Will. Daily actually will be very useful at some point.

Couldn't I get this into monthly values as well by doing some sort of math? How would I go about this?

I'm assuming just adding up the days and dividing by the # of days in that month? I'm assuming its linear that way.

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Also, is there any links out there which give you weekly data for NAO, AO, PNA, WP, EA, EA/WR, TNH, and the GLAAM? Or at least daily numbers then you could just figure out weekly readings that way.

It's nice to see monthly data but there are often times where the month number doesn't exactly tell the entire story of how things exactly transpired that month.

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I'm assuming just adding up the days and dividing by the # of days in that month? I'm assuming its linear that way.

So they don't standardize the data at all?

What I could do then is just add up all the data for an entire month then divide the number of days and just see if that equals the monthly number?

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Thanks, Will. Daily actually will be very useful at some point.

Couldn't I get this into monthly values as well by doing some sort of math? How would I go about this?

First take the average of all the values of each month. Then take all the monthlies from your desired baseline period and average them. Subtract the result from every value in the dataset. Take the standard deviation of all values IN THE BASELINE PERIOD, and divide EVERY VALUE by that number. You can also standardize separately for every month of the year to get a better picture of individual values' significance, but the NOAA does not do that (one look at the AO data confirms this... I personally use my own monthly renormalized dataset when doing correlation work.

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First take the average of all the values of each month. Then take all the monthlies from your desired baseline period and average them. Subtract the result from every value in the dataset. Take the standard deviation of all values IN THE BASELINE PERIOD, and divide EVERY VALUE by that number. You can also standardize separately for every month of the year to get a better picture of individual values' significance, but the NOAA does not do that (one look at the AO data confirms this... I personally use my own monthly renormalized dataset when doing correlation work.

Alright lets see if I have this down...

1. Add up all the daily values for each month then average the sum by the number of days in each month

2. I would then take each monthly number and divide it by the number of years (in this case that would be 69 years...1948-2011) to get an average for each month

3. I would then take each monthly value and subtract it from the average which I computed in step 2.

4. When I have the standard deviation I divide that by the number I computed in step 3.

If this is correct, I can do this process for any of the indices I want?

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I made a rebuild of the EPO, 3 months ago, if anybody wants to use it just goto http://www.wxmidwest.com/epo/

It is updated for September as well...

Have a Good One...

This is pretty awesome! Awesome job and thanks :thumbsup:

Still though would really like to go and see daily data and make weekly readings as well to go along with the monthly data.

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Question...

How did you compile this? Did you use the daily data?

I used excel, and monthly ncar data...

although if you are savy you can use Fortran/C+

but It's quicker to format in excel then compile it in code...

bounded area with mean of 500mb Geo-potential heights

Nope, I used the formula, and then 1 bounded area mean minus another bounded area mean, then standardized for 1981-2010 Climatology, then changed Polarization (+/-)to be in step with EP/NP

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I used excel, and monthly ncar data...

although if you are savy you can use Fortran/C+

but It's quicker to format in excel then compile it in code...

bounded area with mean of 500mb Geo-potential heights

Nope, I used the formula, and then 1 bounded area mean minus another bounded area mean, then standardized for 1981-2010 Climatology, then changed Polarization (+/-)to be in step with EP/NP

Just a few questions so I can hopefully understand this better as I'm totally lost :lol:

When you say "bounded area with mean 500mb heights...what does that mean?

By formula you mean formula used by the CPC, correct? (I could find this on their site?)

1 bounded area mean minus another bounded area mean...?

If you wanted to get the 1981-2010 standardization....are you talking about the 1981-2010 standardization of each individual month or the entire period as a whole? And to find this do you just take all the data from 1981-2010 and do the adding/subtracting/dividing?

changing polarization of the EP/NP...does this just mean you reversed the signs? For example, if Jan 1950 was +0.72 it would then be -0.72?

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I made a rebuild of the EPO, 3 months ago, if anybody wants to use it just goto http://www.wxmidwest.com/epo/

It is updated for September as well...

Have a Good One...

Thats some great info, thanks for the link. I do prefer to keep the sign the way it was though. Its hard to grasp a +EPO has being the cold pattern. But its easy enough to just flip the signs.

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Just a few questions so I can hopefully understand this better as I'm totally lost :lol:

When you say "bounded area with mean 500mb heights...what does that mean?

By formula you mean formula used by the CPC, correct? (I could find this on their site?)

1 bounded area mean minus another bounded area mean...?

If you wanted to get the 1981-2010 standardization....are you talking about the 1981-2010 standardization of each individual month or the entire period as a whole? And to find this do you just take all the data from 1981-2010 and do the adding/subtracting/dividing?

changing polarization of the EP/NP...does this just mean you reversed the signs? For example, if Jan 1950 was +0.72 it would then be -0.72?

yes, if you goto the page the formula and bound areas for 500mb geopot heights are there, at the top.... 2 lat-lon confined boxes (bounded areas) , 1 Box Minus the Other, as far as the standardization goes, you pretty much explained it, use data from 1981-2010 climatology as a way to standardize the entire dataset.

Yes, I changed signs.. hopefully some folks can get some use out of it. I hear some folks at one of the stations in Alaska NWS stations are taking advantage of it..

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yes, if you goto the page the formula and bound areas for 500mb geopot heights are there, at the top.... 2 lat-lon confined boxes (bounded areas) , 1 Box Minus the Other, as far as the standardization goes, you pretty much explained it, use data from 1981-2010 climatology as a way to standardize the entire dataset.

Yes, I changed signs.. hopefully some folks can get some use out of it. I hear some folks at one of the stations in Alaska NWS stations are taking advantage of it..

Awesome, thanks! This definitely is a great link and great work. I'm sure many should make great use out of it.

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Thats some great info, thanks for the link. I do prefer to keep the sign the way it was though. Its hard to grasp a +EPO has being the cold pattern. But its easy enough to just flip the signs.

I'm with you, I've never adjusted to the new EP/NP stuff because of the difference in sign.

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weatherwiz, they do, but never have consistent daily datasets, I've seen them browsing ftp directories...

It's just not kept up, here is an example:

http://www.cpc.ncep.noaa.gov/products/SCM/archive/ond2010/daily_teleconnections.index

back track into the dirs, the data is really incomplete..

That's pretty awesome just too bad there isn't consistent datasets.

I've tried to do something like this in the past but stopped for a while and never got back.

What I was doing was just using the reanalysis maps and looking at the 500mb height patterns for a two-week period. For example, I was doing the NAO and I started with January 1st, 1950-January 13th, 1950 and looked at what the height anomalies were in the NAO region to determined if it was positive or negative or somewhat neutral.

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The Daily Data it there, it's in NC form, I want to find something to read it.... the Direct daily GH values then make daily TeleC's from that. Just don't have the skill to open those .nc datafiles yet...

I see...I definitely don't have the skills to open files like that or would even know how :lol:

Good luck though!

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  • 4 weeks later...

Here's an excel file of daily and weekly NAO data. Daily data is in the first tab along with 7 day moving average. The second tab is weekly data only (easier and shorter to read). I calculated by doing a simple 7 day average. The 'correct' way might have been to re-standardize it or to calculate it based on weekly 500mb composites, but it would make very little difference. December 31st and sometimes December 30th are left out of the weekly data because I did not do a 53rd week for those 1 or 2 days. I can do it for the PNA and/or AO too if you'd like.

http://www.mediafire...pnafho66ihoc51e

Data source:

ftp://ftp.cpc.ncep.noaa.gov/cwlinks/

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