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View Full Version : Southern Mountain giving Mt Washington a run in wind speed



AlpineHikerFan71
02-19-2007, 08:54 PM
Looks like we have some competition from the southern Appalachians for highest wind speed. Except the one they put up on top of the mile high swinging bridge at Grandfather Mountain, only goes up to 224 mph still 7mph short of the rockpiles world record. It also has a built in feature that keeps it from freezing up, but then again they dont have as many foggy days where the rime ice accumalates like our Mt Washington

Here is the article link from a WInston Salem, NC newspaper

http://www.journalnow.com/servlet/Satellit...SJ_BasicArticle

treant985
02-19-2007, 11:08 PM
Looks like we have some competition from the southern Appalachians for highest wind speed. Except the one they put up on top of the mile high swinging bridge at Grandfather Mountain, only goes up to 224 mph still 7mph short of the rockpiles world record. It also has a built in feature that keeps it from freezing up, but then again they dont have as many foggy days where the rime ice accumalates like our Mt Washington

Here is the article link from a WInston Salem, NC newspaper

http://www.journalnow.com/servlet/Satellit...SJ_BasicArticle

That link doesn't seem to work...let's see if copying and pasting this one does:

www.journalnow.com/servlet/Satellite?c=MGArticle&cid=1149193235109&pagename=WSJ/MGArticle/WSJ_BasicArticle

I live in Winston-Salem (hometown for the paper article above), and have a house that's very near to Grandfather Mountain; the house is on Beech Mtn (bragging rights of highest incorporated town on the east coast).

The mountains of NC (esp. Grandfather and Mt. Mitchell) have a lot in common with those of NH. The all-time high at MWO is 72; the highest I found for Mt. Mitchell, back almost 80 years (although missing a big chunk of the 1940s and 1950s) was 81. As already shown, they can also get rather windy.

Even a lot of North Carolinians don't know about the mountains here. I've often left Winston-Salem in the 70s and arrived to Beech in the teens, which isn't much for you northeasterners, but still a pretty big change in temp for just 2 hrs in the car in North Carolina, which definitely doesn't have a 'cold reputation.'

treant985
02-20-2007, 12:19 AM
I went to the Grandfather Mtn website and looked at their old data. They've got high wind gusts for most days, back 50 years. Here are the highest they've recorded, although it's skewed towards recently due to better equipment over the years:



DATE GUST
01-25-2006 203.55
04-18-1997 195.50
02-28-2006 195.05
04-03-2005 194.35
04-02-2005 192.05
10-29-2006 192.05


The wind gusts have such weird decimals because they're measured in knots by their anemometer, then converted to MPH later.

Brad
02-20-2007, 05:25 AM
To get a idea what these mountains are like here are some pictures of hikes I did with my 2 grandchildren.

Grandfather Mt.
http://public.fotki.com/bradbradstreet/hikes/2005_hikes/09_grandfather/

and
http://public.fotki.com/bradbradstreet/hikes/2005_hikes/06_grandfather/

Mt Mitchell
http://public.fotki.com/bradbradstreet/hikes/2006_hikes/07_mt_mitchell/

and
http://public.fotki.com/bradbradstreet/hikes/2006_hikes/06_mt_mitchell/

Bill O
02-20-2007, 07:20 AM
Nobody really talks about Grandfather Mountain because their data is so suspect. The old anemometer location was totally un-scientific.

Approaching 200mph a couple times a year...come on. If that was really the case this forum probably wouldn't exist. Let's just wait and see what their new anemometer reports.

afmrintern
02-20-2007, 08:50 AM
Nobody really talks about Grandfather Mountain because their data is so suspect. The old anemometer location was totally un-scientific.

Approaching 200mph a couple times a year...come on. If that was really the case this forum probably wouldn't exist. Let's just wait and see what their new anemometer reports.

According to these articles, it seems that you are right on the mark:

http://www.boston.com/news/local/new_hampshire/articles/2006/04/03/scientists_grandfather_mountain_work_on_accurate_w ind_gauging/

http://www.dancaton.physics.appstate.edu/Columns/GFMweather.htm

AlpineHikerFan71
02-20-2007, 09:39 AM
Nobody really talks about Grandfather Mountain because their data is so suspect. The old anemometer location was totally un-scientific.

Approaching 200mph a couple times a year...come on. If that was really the case this forum probably wouldn't exist. Let's just wait and see what their new anemometer reports.

Bill,
you are correct. Last time I was there and hiked Grandfather mountain looked up at the building there and that is where the anemometer is located so whent he winds blow up agaisnt the building the speed increases.

Sorry to out friends in NC, it is a beautiful area down there and have been vacationing in Banner Elk, NC but the wind speeds of the past I really cannot buy into. Like Bill said let see what the anemometer reads and then see. I do know that it can get quite windy down there though and am sure they have had wind speeds that are high but let see what the new anomemeter reads in the future.

But congrats to a beautiful area of the southern Appalachians down there. Sad to see the acid kill the firs on top of Mt. Mitchell as well, another great place.

Bill O
02-20-2007, 09:40 AM
The Winston/Salem article also mentions how recording wind speeds at those ranges is very inaccurate.

That's not exactly true. With a 3-cup Davis anemometer that may be the case, but with a static-pitot tube that argument is dead wrong.

The pitot tube is what airplanes use to measure their air speed, typically well above 200mph. They are accurate enough to allow planes to be spaced on approach. They are also accurate enough to allow the F-15's to fly over a stadium at the precise moment the National Anthem ends. Sure, GPS is involved, but airspeed is very important.

AlpineHikerFan71
02-20-2007, 09:47 AM
To get a idea what these mountains are like here are some pictures of hikes I did with my 2 grandchildren.

Grandfather Mt.
http://public.fotki.com/bradbradstreet/hikes/2005_hikes/09_grandfather/

and
http://public.fotki.com/bradbradstreet/hikes/2005_hikes/06_grandfather/

Mt Mitchell
http://public.fotki.com/bradbradstreet/hikes/2006_hikes/07_mt_mitchell/

and
http://public.fotki.com/bradbradstreet/hikes/2006_hikes/06_mt_mitchell/
Brad,
Some awesome photos there, brought back alot of memories from the late 90's when a good friend and mine hiked down there, makes me want to go back down there again. We went in mid fall (Early Oct). I wish I had a digitial camera then. but thanks again, awesome

treant985
02-20-2007, 10:31 AM
Nobody really talks about Grandfather Mountain because their data is so suspect. The old anemometer location was totally un-scientific.

Approaching 200mph a couple times a year...come on. If that was really the case this forum probably wouldn't exist. Let's just wait and see what their new anemometer reports.

I agree that several 190+ readings in a year is pretty unlikely. However, isn't it true that MWO has never observed another 180+ since that day with 231? I'm just going on memory from an old weather book by Ludlum, so I'm not sure. Was the 231 gust measured with a pitot?

Bill O
02-20-2007, 10:50 AM
I agree that several 190+ readings in a year is pretty unlikely. However, isn't it true that MWO has never observed another 180+ since that day with 231? I'm just going on memory from an old weather book by Ludlum, so I'm not sure. Was the 231 gust measured with a pitot?

I think that is true, unless it was in April, because nothing outside April is over 180mph.

The 231 was recorded with a modified 3-cup, not a pitot. Well, it worked on the same principal as a 3-cup.

treant985
02-20-2007, 04:52 PM
I think that is true, unless it was in April, because nothing outside April is over 180mph.

The 231 was recorded with a modified 3-cup, not a pitot. Well, it worked on the same principal as a 3-cup.

Do you know off-hand of any articles or studies that were done about the 231mph gust? I found some stuff in the June 1934 Monthly Weather Review, but I'm hoping for something a little more recent.

I'm sure a bunch of people questioned such a high reading during a minor storm, so it seems like there'd be several articles done where the author tried to verify/refute the reading.

The Grandfather Mtn anemometer only being able to go to 224mph reminds me of a similar circumstance in Alaska. Everyone there claims they'll never be able to officially break the North American low temp record (-81.4 in Snag, Canada) because the NWS minimum thermometers only go to -80. Of course, they could mark the glass if the mercury drops lower, but it'd be an ordeal to get the thermometer tested later, for accuracy.

Bill O
02-20-2007, 05:06 PM
I don't know any, but I'm sure they are out there.

I did stumble onto this information on MWO's site:

Wind Record (http://www.mountwashington.org/about/visitor/recordwind-1997challenge.php)

It's good to know that there is a National Extremes Committee, and that they agree that Mount Washington's 231mph is the record. I have a feeling there is a World Extremes Committee as well, and they also agree.

Mike D
02-20-2007, 05:49 PM
The Grandfather Mtn anemometer only being able to go to 224mph reminds me of a similar circumstance in Alaska. Everyone there claims they'll never be able to officially break the North American low temp record (-81.4 in Snag, Canada) because the NWS minimum thermometers only go to -80. Of course, they could mark the glass if the mercury drops lower, but it'd be an ordeal to get the thermometer tested later, for accuracy.

It doesn't detract from your point, but as I understand it, mercury is never used in thermometers for readings that low. Alcohol is typically found in low thermometers, but I wonder if the ones in question are digital, not using any liquid at all.

treant985
02-21-2007, 12:04 AM
It doesn't detract from your point, but as I understand it, mercury is never used in thermometers for readings that low. Alcohol is typically found in low thermometers, but I wonder if the ones in question are digital, not using any liquid at all.

Thanks for correcting my post. I'm usually the one who tells people that they use alcohol in the minimum thermometers, instead of mercury. I think that, as long as it's deemed an accurate device, observers can use whatever kind of thermometer they want.

I've read that the observer in Embarrass, MN, used a digital one until it broke at -64F on the coldest day anyone had recorded in MN. It cost him the state all-time low record (to nearby Tower, which got to -60), even though he had labs verify the -64 reading. He switched to alcohol minimum thermometers after that.

It's been a while since there were temps in AK down to -75 or lower (Jan 1989 I believe), so I bet that all those were done with alcohol thermometers, but it would be interesting to see how many places use digital ones now.

treant985
02-21-2007, 06:37 PM
I don't know any, but I'm sure they are out there.

I did stumble onto this information on MWO's site:

Wind Record (http://www.mountwashington.org/about/visitor/recordwind-1997challenge.php)

It's good to know that there is a National Extremes Committee, and that they agree that Mount Washington's 231mph is the record. I have a feeling there is a World Extremes Committee as well, and they also agree.

Here's a little background info that I came across:

I read a report by the Army Corps of Engineers from 1985 that mentions global weather extremes. They say that "in such strong winds, no apparatus can record the airflow except approximately, and actual velocity (of the 231 gust) may be in error by 10 to 40 miles per hour."

However, "a value of 225 MPH, after anemometer calibration, is given in some sources." I guess, after a while, they figured the 231 was close enough to not warrant any corrections.

Interestingly, the Army report says that the 231mph gust had the same force as a 180mph gust at sea level, which may put the 207mph gust at Thule, Greenland (elev. 990ft), as #1 in terms of actual force.

By the way, this Thursday is supposed to be windy up in the NC mountains, so it'll be interesting to see if the new anemometer at Grandfather Mtn is reporting data publically by then. I emailed them to ask if the data currently online is from the new one or the old anemometer, but I've yet to hear back.

Bill O
02-21-2007, 06:51 PM
Here's a little background info that I came across:

I read a report by the Army Corps of Engineers from 1985 that mentions global weather extremes. They say that "in such strong winds, no apparatus can record the airflow except approximately, and actual velocity (of the 231 gust) may be in error by 10 to 40 miles per hour."

However, "a value of 225 MPH, after anemometer calibration, is given in some sources." I guess, after a while, they figured the 231 was close enough to not warrant any corrections.

Interestingly, the Army report says that the 231mph gust had the same force as a 180mph gust at sea level, which may put the 207mph gust at Thule, Greenland (elev. 990ft), as #1 in terms of actual force.

By the way, this Thursday is supposed to be windy up in the NC mountains, so it'll be interesting to see if the new anemometer at Grandfather Mtn is reporting data publically by then. I emailed them to ask if the data currently online is from the new one or the old anemometer, but I've yet to hear back.

Well, that report is flat out wrong. A 231mph gust at 6,288ft would feel stronger at sea-level...no matter how you cut it. The air is denser at sea-level, so at the same speed it exerts more force.

I'd also hold a serious argument to an error of 10-40mph. Maybe in 1934, maybe with a 3-cup at 200mph, but not with a pitot tube. The claim that no device can measure such high winds accurately is crazy. Did they not have sonic anemometers back then? What about wind tunnels? The produce wind over 150mph in those, and I bet they measure it accurately within 1-2%.

How about the space shuttle? I'm guessing their pitot tube used for landing measures airspeed using decimal places.

treant985
02-21-2007, 07:52 PM
Well, that report is flat out wrong. A 231mph gust at 6,288ft would feel stronger at sea-level...no matter how you cut it. The air is denser at sea-level, so at the same speed it exerts more force.

I'd also hold a serious argument to an error of 10-40mph. Maybe in 1934, maybe with a 3-cup at 200mph, but not with a pitot tube. The claim that no device can measure such high winds accurately is crazy. Did they not have sonic anemometers back then? What about wind tunnels? The produce wind over 150mph in those, and I bet they measure it accurately within 1-2%.

How about the space shuttle? I'm guessing their pitot tube used for landing measures airspeed using decimal places.

Yea, since the report is over 20 years old, it doesn't factor in any newer wind-sensing instruments. Just think of how much technology in general has advanced in the past 20 years. I think part of the 'discrepancy' between measuring wind speeds has to do with the fact that devices in wind tunnels are probably much better at measuring a constant stream of air, compared with anemometers that have to adjust quickly to rapidly-changing gusts. If the wind kept up at 231mph for maybe half a minute (in the 1930s) or a full second or two (nowadays) then it would obviously be a lot more reliable reading compared to just a quick burst that registered 231mph.

I think you've got the right idea about the wind force but may have just incorrectly read my post. I meant that the 231mph gust at 6288 feet is equivalent in force to a 180mph gust at sea level, so you're right that 231mph at sea level would feel much stronger than it would at MWO.

The 10-40 mph 'error' was only in reference to the device used to measure 231mph in the 1930s, not the standard error one can expect in any attempted measurement of winds that strong.

treant985
02-21-2007, 07:56 PM
I just read another forecast for the NC mountains that say that the winds this Thursday and Friday could be the strongest yet this winter. I guess that doesn't necessarily mean the strongest gusts, but I'll keep an eye on the Grandfather Mtn (and Mt. Mitchell, too) online live weather stations to see if any register a triple-digit gust.

Bill O
02-21-2007, 08:02 PM
Sorry, I did read that wrong. 231mph at 6,288 would feel like 180mph at sea level. Sorry about that. But if you are looking at how fast the air particles are moving over the summit, 231mph is always 231mph.

The beauty of the pitot is that it continuously measures the wind. It doesn't sample once every 5 seconds or .1 seconds, it is continuous. Save for some compression of the air in the tube.

Now, the 1934 device and many other types of anemometers have momentum. They can't physically capture a one second gust. The tend to dampen out the gusts.

Arthur Dent
02-22-2007, 07:10 PM
Bill O-"The 231 was recorded with a modified 3-cup, not a pitot. Well, it worked on the same principal as a 3-cup."The anemometer that was used to measure the 231 mph wind was known as 'old No. 2' and it is located in the museum on the summit. It wasn't a 3 cup but about a 6" diameter cylinder or drum, maybe 2" thick, with 6 'scoops' on its diameter to catch the wind. The wind speed was measured by timing 'clicks' from electrical contact closures made every so many revolutions of the drum. There is a photo of this anemometer (between p170 and p171) in 'The Worst Weather on Earth' published by the MWO in 1991.

Bill O
02-22-2007, 08:12 PM
The anemometer that was used to measure the 231 mph wind was known as 'old No. 2' and it is located in the museum on the summit. It wasn't a 3 cup but about a 6" diameter cylinder or drum, maybe 2" thick, with 6 'scoops' on its diameter to catch the wind. The wind speed was measured by timing 'clicks' from electrical contact closures made every so many revolutions of the drum. There is a photo of this anemometer (between p170 and p171) in 'The Worst Weather on Earth' published by the MWO in 1991.

That's right. I kept the description simple since a 3-cup and old no 2 both work on the same principal...they spin in a circle. And wind speed is proportional to have fast it spins.

When I left the Obs a few years ago they were testing a modern day "old no 2." Essentially a large steel drum with scoops that spins in a circle, heated by a stove coil. To say the least, it was scary to be near when spinning at any speed.

treant985
12-20-2007, 06:35 PM
Grandfather Mtn. has a been using a new anemometer sited according to standard observation rules since Feb of this year.

This last weekend was pretty windy in the NC area. I emailed the caretaker of the mountain; he said their top gust was 98mph with sustained winds of 60+. Not much compared to MWO's windy days, but still pretty impressive to approach 100mph.

I believe they recorded a 102mph gust on Nov 10, which is their highest reading using the new anemometer in a better location.

Bill O
12-20-2007, 06:43 PM
Grandfather Mtn. has a been using a new anemometer sited according to standard observation rules since Feb of this year.

This last weekend was pretty windy in the NC area. I emailed the caretaker of the mountain; he said their top gust was 98mph with sustained winds of 60+. Not much compared to MWO's windy days, but still pretty impressive to approach 100mph.

I believe they recorded a 102mph gust on Nov 10, which is their highest reading using the new anemometer in a better location.

It would be interesting if they still had the old anemometer running at the same time. Then they could compare how ridiculous their old data is.

Mike D
12-21-2007, 12:57 PM
It would be interesting if they still had the old anemometer running at the same time. Then they could compare how ridiculous their old data is.

We will be running a wind comparison study (summer only) to compare the record wind site, the new instrument tower, and a few other summit locations. It will be interesting to compare strong winds from different directions at different spots around the summit.

Of course, our study will use identical instruments, whereas Bill's idea for Grandfather Mtn is to compare their anemometers.

Bill O
12-21-2007, 02:02 PM
We will be running a wind comparison study (summer only) to compare the record wind site, the new instrument tower, and a few other summit locations. It will be interesting to compare strong winds from different directions at different spots around the summit.

Of course, our study will use identical instruments, whereas Bill's idea for Grandfather Mtn is to compare their anemometers.

That's great. Can't wait to see the data.

treant985
12-23-2007, 12:08 PM
Beech mtn in NC recorded 86.3mph gust this morning. I believe that Grandfather's station is still down since the solar panel blew away this last weekend and messed up their electronics.

BillPatt
12-24-2007, 10:14 AM
Mercury is never used in low temperature thermometers for one simple reason - it turns into a solid at about -40F (or -40C).

Wikipedia lists it as -38.83C, -37.89F

treant985
12-24-2007, 11:51 AM
Maybe this has been discussed elsewhere, but does anyone have a list of, say, the top 10 or 15 gusts recorded at Mount Washington? I can use the monthly charts to find the highest for each month, but of course that just shows the strongest and may miss other high ones that just missed being that month's strongest.

Bill O
12-24-2007, 01:26 PM
Maybe this has been discussed elsewhere, but does anyone have a list of, say, the top 10 or 15 gusts recorded at Mount Washington? I can use the monthly charts to find the highest for each month, but of course that just shows the strongest and may miss other high ones that just missed being that month's strongest.

I've never seen it, but it could be easily extracted from the database.

You might have to say that only one peak gust can count per day. Otherwise, I bet all 10-15 occured on the same day as the 231mph gust.

treant985
01-28-2008, 09:53 PM
We will be running a wind comparison study (summer only) to compare the record wind site, the new instrument tower, and a few other summit locations. It will be interesting to compare strong winds from different directions at different spots around the summit.

Of course, our study will use identical instruments, whereas Bill's idea for Grandfather Mtn is to compare their anemometers.


I hope that the info from the study will be available online once it's done. Mike, do you have any info like what kind of equipment you'll use, a map of where the anemometers will be located, etc?

I believe there's an article on this website somewhere that claims that the change of location in 1980 may be the reason why the observatory hasn't really come close to a 200 mph reading since the record. So the study this summer could be very interesting.

Would there be any chance of having multiple permanent anemometers year-round in the future (based on what the study returns), and visitors to the site can see both readings (or at least the higher one)?

FisherCat
02-01-2008, 07:56 PM
We will be running a wind comparison study (summer only) to compare the record wind site, the new instrument tower, and a few other summit locations. It will be interesting to compare strong winds from different directions at different spots around the summit.

Of course, our study will use identical instruments, whereas Bill's idea for Grandfather Mtn is to compare their anemometers.
Any heads up on the locations? I've always thought for all the hiking we've done up there that we have almost been blown over in Edmands Col, only to emerge out and there hardly be any wind at all elsewhere. I know this has something to do with the topography of that area, so is there a certain criteria that will be met by the satellite sites?