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PostPosted: Sun Jan 15, 2006 7:46 pm 
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Fred just tried the latest script and it plotted a empty map. Seems like there should be some fog somewhere in the US.


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PostPosted: Sun Jan 15, 2006 8:01 pm 
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Location: Suoi Tien, Vietnam
I have tested for the US and it give some fog. Are you sure you deleted all trailing spaces?

Fred


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PostPosted: Sun Jan 15, 2006 8:33 pm 
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Location: Bristol, UK
Hi Fred,

Thanks for the feed-back.

I obtained my formula from a web site that gives

FSI=(Tsurface-T850)+(Tsurface-surface Dew point)+Wind850

I've plotted your script along side mine and, funnilly enough, they give very similar results!

Using my information I've taken 20 as being the critical value of a high chance of fog. It's interesting to see that your value of 31 falls, again, in a similar place to mine. In my script I've tried to suggest increasing chances of fog with shading.

The plot thickens (or should I say the fog thickens)!

We need a referee to give us some definitive guidance.

Any takers?

Regards,

Dave.


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 Post subject:
PostPosted: Sun Jan 15, 2006 8:41 pm 
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Hello Dave

Yes, up to now I saw 4 different formulas for fog. Programming it is not difficult but first someone must give the right formula.

Who can help?

Greetings

Fred


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 Post subject:
PostPosted: Sun Jan 15, 2006 8:55 pm 
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Location: Bristol, UK
Hi Fred,

One thing I've noted is that in general, despite the fact we haven't yet sorted this officially, the areas that show up as high fog risk areas, both with your script and mine do seem to corespond with plotted areas of fog or at least mist.

True, there are some fog plots outside the limits, and indeed some plots of good visibility within the limits, but in general i have seen some sensible results.

Kinetic,
Are you having luck with Fred's script or mine yet?
I definately had a good plot for the States last night, and that was before I made any changes.

Regards,

Dave


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 Post subject:
PostPosted: Sun Jan 15, 2006 10:53 pm 
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Hi Dave
The script seems to be working, here is a link to my output.

http://cascadwx.com/MAPS/fog.gif


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PostPosted: Mon Jan 16, 2006 7:11 am 
Hey gang:

I copied the two scripts that were on here, and ran each one. Then I tweeked the original script, but now get funky results. Here is the modified script:

#Fog stability Index-------FSI=(Surf temp-850mb temp)=(Surf temp-Surf Dew point)+850mb windspeed.#

ANALYZE,OVER FILL COLOR=121:121:121 FILS=4 GRTN=10 STOR=1
ANALYZE,OVER FILL COLOR=164:164:164 FILS=2 GRTN=20 STOR=2
ANALYZE,OVER FILL COLOR=210:210:210 FILS=0 GRTN=30 STOR=3
ANALYZE,OVER FILL COLOR=159:255:255 FILS=0 GRTN=40 STOR=4
ANALYZE,OVER FILL COLOR=255:255:166 FILS=0 GRTN=50 STOR=5
ANALYZE,OVER FILL COLOR=0:196:0 FILS=0 GRTN=60 STOR=6
ANALYZE,CONT EQUA=20 COLOR=255:0:0 LINE=3 CINT=10 LINE=2 COLOR=0:0:0
STOR=7 SSUM=1:2 STOR=8 VKNT WSPD H850 STOR=1 SSUM=2:3 STOR=2 SDIF=1:2 STOR=1 TEMP HSFC STOR=2 TEMP H850 STOR=3 SDIF=1:2 STOR=4 DWPT HSFC
ANALYZE,CONT CINT=5 DOTS STOR=5 SSUM=1:2 STOR=2 VKNT WSPD H850 STOR=1 SSUM=2:3 STOR=2 SDIF=1:2 STOR=1 TEMP HSFC STOR=2 TEMP H850 STOR=3 SDIF=1:2 STOR=2 DWPT HSFC
stamp

I am not much of a script geek, but could someone advise me why the results are poor? I don't know, maybe someone will come up with something more solid.

Thanks,
Randy


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 Post subject:
PostPosted: Mon Jan 16, 2006 9:00 am 
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Joined: Tue Nov 25, 2003 4:22 pm
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Location: Suoi Tien, Vietnam
As I already explained before here the original script cannot work. It starts with displaying something without analyzing it before. You can test this by yourself:
1. Run a completely different script (if possible something for a stability factor, then a STOR-command is used)
2. Now run the fog-script. You will see that the output will more or less look like the output from step one. In fact it displays the contents of the STOR-command of step 1 that are still in memory.
3. Run the fog-script again. This time you will get pretty good results. This is because the last part of the script (the analyse) is OK and this time it displays the results of step 2 that are still in memory (the STOR-command).

My last script should work better, because it starts with the analyzing part. Problem here is that I found 4 different formulas for fog. Which one is correct? Who can give the one and only right formula?

Greetings

Fred


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 Post subject: Re: fog scripts
PostPosted: Mon Jan 16, 2006 6:23 pm 
Hi Fred:

I must have missed your first post somehow, but if the original script is invalid, why use it? As to you coming up with four different formulas for fog, I'm not sure there IS a correct one. I would think you use the formula which yields the best results based on trial and error, and other data. But hell, what do I know??? :lol:

RG


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 Post subject:
PostPosted: Mon Jan 16, 2006 6:48 pm 
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Joined: Tue Nov 25, 2003 4:22 pm
Posts: 198
Location: Suoi Tien, Vietnam
My script was posted: Sun Jan 15, 2006 5:42 pm on page 1 of this topic. I am afraid that my meteorologic knowledge is still not enough to decide if the script and the formula is correct. So if some people will try this script and tell me if this is the right formula or they give a better one I will modify the script.

Greetings

Fred


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