What can I say but it really sucks down here in Patagonia.   Of course that is only the weather I’m talking about!  Everything else about Chalten is great.  Plenty of good people to hangout with, good climbing in town and no lack of food to eat.   We’ve only been here ten days but it seams like much longer, it also feels like we have to leave in no time at all (though we really have till the 6th of Feb).

I spend a lot of my time staring at my computer looking at every different available weather forecast on the internet, hoping that one of them is going to show good weather.  Right now they all show bad weather.  In a recent NatGeo Magazine article by Kenneth Brower I came across of very fitting quote describing the weather down here.

“…for these far southern latitudes circumscribe  the entire globe almost without interruption by land.  Low pressure areas are free to chase one another eastward around the bottom of the planet like a howling dog in pursuit of its own tail.”

The above quote is entirely true but occasionally the dog does get dizzy enough that he can’t find his tail and there is a moment of calm weather.  Here are some of the charts we look at to figure exactly when that is going to happen:

The low pressures system are completely free to roam at 60S

This is our main source of weather info

The above meteorogram is produced from NOAA and is available for any latitude and longitude.  You can find the website we use here:   http://ready.arl.noaa.gov/READYcmet.php The lat and long we use is for Cerro Torre which is approximately  -49.19 and -73.1 and the dataset we use is the GFS 0-180 hr.

The the bottom data set from the chart above is showing Mean Sea Level pressure.  We want it to be high as good weather is almost always associated with high barometric pressure.  When the really good weather hits the MSL pressure will go above 1020 HPA and stay around there for a few days.    We also need to look at the winds as they are the most ferocious part of the weather down here.  We’ve found climbing in weather with winds of 10 Knots or above is almost impossible and generally no fun.  Good weather will have winds below 5 knots.  And then there is the precicpitation which is shown with the green bars that represent millimeters in 3 hours.  Obviously lower the number is better.  We have found  that generally when the precip totals are below 3mm every three hours it is climbable.

Another site I use to double check the NOAA site is meteoexploration.com There’s lots of cool weather info there for mountain ranges all over the world.  If you are at interested in mountain weather go check it out.

Same as the NOAA chart with a few more pieces of data

And lastly for a good visual over view of what is actually happening with the high and low pressure systems I goto a US Navy site here: https://www.fnmoc.navy.mil/ and choose the 1000-500 Thickness [dm] and Sea Level Pressure [mb] loop chart for South America.

Sea Level Pressure Chart with 6hr Precipitation totals

What we want this chart to show is the high pressure system sliding down farther southeast and resting around 50s and 70w.  Currently the high pressure is way to far north and the boundary between the high and the low systems is running right over over us.  This is bad.  It is also bad when the lines become closer together. The closer the lines the steeper gradient between the high and the low systems which makes the winds even faster!

Hopefully in the next few weeks the dog will indeed get tired of chasing his own tail and we will actually get to go climbing!  If not I may go crazy enough to start chasing my own tail.