I've been playing with the program since some days. I'm new at it.
My first impression are very good but the program need some enhancement about the icons displaying the current or forthcoming weather. Currently it is really sad, everything is designed blank. If you want your program to be widely used, you should definitely work on that area. Most people want to know by a glimpse what is the current weather but also what is the weather for the next few days. If I look at the next 3 days, the icons are not appealing. I have a sun or I have a sun with clouds next to it. But there are a lot of tendancies. Cloudy with no sun, lightly cloudy with sun, heavy clouds with sun, rain, showers rain with sun, thunderstorm, hailstorm, etc...
Let me give you some example of a french program I use - you can find it here http://www.lachainemeteo.com/meteo-bure ... -meteo.php
http://img846.imageshack.us/img846/4940/chainemeteo.png
It is multiple snapshots of different cities in France and I edited the snapshot in Paint.
As you can see, with just a glimpse, you immediately see what is the current weather but also what will be the weather tomorrow and after tomorrow, etc... Same for the temperature. With yowindow, we only have the maximum temperature for the next three days. But I'm sure people would like also to know what will be the lowest. Must I leave my home with only my shirt or must I take my scarf?

In A you can see sun with medium clouds.
In B you can see the next day is less cloudy. Immediately you notice it. Currently I can't notice that in yowindow and for me it is a major drawback. It lacks some nice, appealing, pleasant icons you can immediately determine what the weather will be.
In C you can see a very nice icon displaying rain shower with some sun.
In D we have a thunderstorm with rain and some sun.
It would be great to have similar icons, for each possible weather condition we should have a specific icon, a nice, appealing, attractive icon.
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Could it be possible as I've mentioned just above to add the minimum temperature for the previsions? And also the possibility to remove the wind previsions? What is great in your program is that you can tick or untick almost everything. That is REALLY great because many times you can't set the program the exact way you want. However the wind previsions are displayed by default and cannot be removed. So an option to display temperature, wind and maybe more options should be perfect. The end-user must decide what is displayed.
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My last suggestion should be to add a pressure history for the last 30 hours. When you have an indication of pressure 1030hPa decreasing, what that really means globally? One hour ago the pressure was 1031 or 1040, this is not the exact same thing. With an diagram history, we could immediately see how the pressure performed the last 30 hours. Let me give you an example of what we could get:
http://img854.imageshack.us/img854/7159/yotry.png
I summarize in that picture all my current wishes.
1 - New icons. I just quickly copy the icons of my french program described above, in the yowindow. It is not perfect of course, it is just to give an idea. Suddenly the previsions look more appealing aren't they?

2 - The minimum temperature are displayed. And of course those who don't want to see the minimum temp could untick inside the options program. Same for the wind or the high temp.
In area "B" (top of the image), the time bar with weather. I don't know how it really works now. I just give you my opinion of what as an end-user I should be glad to see there.
Say we are at 08h00AM. The prevision for the day are sun the morning and sun with a bit of clouds the afternoon. We would then have what is displayed in my image. Then the morning goes by and it rains instead of sun. I should be glad the time bar retains that information and when we are at 20h00PM, someone asks me what was the weather, I can show him: look, this morning it was raining and this afternoon was a bit cloudy with sun.
I don't know how complicated this can be to code but just an idea.
3 - My pressure history. Very usuful to have the history back to 30 hours. And you can notice aboce the figures a white arrow pointed down. If people don't want that pressure history, they just have to press the arrow and the diagram disappear and everything is back to normal, as now. And people like me willing to see the history would click on it to display the diagram. Everybody is satisfied.
On the right the number indicates in hPa how much each bar at different times fluctuated. In my image, 12 hours ago, we are at +5. So as currently we are at 1031hPa, 12 hours ago we were at 1036hPa. With such a clear diagram, you immediately see how the pressure fluctuates.
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A last request: could you please add the possibility to display the moon rise and moon set? If you can, would be a nice addition.
And thank you for your great program.
