View Full Version : Weather geeks: Finding prevailing wind info?

08-04-2014, 03:41 PM
I'm planning my horse barn and I'm trying to decide on how to orient it to take advantage of summer breezes and block the worst of winter's winds. I'm in SC so the barn is going to be pretty simple & open since heat really is more of an issue than cold.

We've only been here a year, and I know where most of last year's winter winds came from, but that was supposedly an "unusual" winter. I've been looking for a map or table or something with general historical weather trends that include wind direction, and my Googling is getting me nowhere.

Anyone have any useful links or leads?

08-04-2014, 04:22 PM
Search for "wind rose" + "your town" for your area.

NOAA (National Weather Service) and/or USDA (Dept of Agriculture) should have that data for your hometown's airport on their website. --broken down by month.

Chessic Sense
08-04-2014, 05:29 PM
Keep in mind that major weather patterns are spirals. If the wind is northerly one day, it'll be southerly later as the pattern passes through. The only way to get it really lopsided is to consistently hit the top (or side or bottom) of high-pressure systems and the opposite for low-pressure systems. A canyon or something, of course, always changes the surface winds so that might override anything else.

08-05-2014, 08:15 AM
Fantastic, just what I needed, thanks!

Now, how do I read the thing? (http://jenk.org/G3.bin/var/albums/swj_pics/wind%20rose.gif?m=1407243094) :p

Is this telling me that the strongest gusts (storms) tend to come from the west, or that the wind in general is mostly out of the west ?

08-05-2014, 09:55 AM
Is this telling me that the strongest gusts (storms) tend to come from the west, or that the wind in general is mostly out of the west ?

The way I read it, it's not telling you anything about gusts, but about mean wind speed. In this case it's saying that the wind will be directly out of the west most often by a small margin, about 8% of the time (which makes sense as prevailing westerlies are the norm). Just eyeballing the bars for that, it will be 19-25 mph around 0.3% of the time, 13-19 mph more than 1% of the time, 8-13 mph around 1.2% of the time, 4-8 mph also around 1.2% of the time, and 1.3-4 mph 1% of the time. Repeat for all the other directions. West winds will be most prominent and slightly stronger on average, followed by east winds, followed by WSW. It will be calm 31.2% of the time. Pretty neat info, actually.
ETA: One thing this is NOT telling you is how this might vary by season.

08-05-2014, 10:24 AM
Try this link for Columbia:


That link will go to July 2014, but you can select any month in any year, and look at the bottom red-line chart to see the wind direction at several reporting times for every day that month.