Slashdot Mirror
Perfect Weather on the Net
ctwxman continues:
I always like to start at NCEP (National Centers for Environmental Prediction) for a look at the dynamic models. Each is run using somewhat different equations, making them often come up with different, quite contrary solutions. Some of these models, like the GFS are worldwide in their coverage and forecast out an amazing 16 days (note: the word accurately was not used in the last sentence). Once the dynamic models are through, we can massage them against past performance under similar circumstances at specific places. These are the statistical models, referred to as MOS (Model Output Statistic) models. Again, there are somewhat different solutions from different models. If none of these work for you, run your own. There are programs available to allow you to run your own model, specifying the domain, grid spacing, time interval, etc. The most commonly used research model of this type is the MM5, produced at Penn State University. Run it on your PC! Of course, it's freely available and supported. Sometimes, the data you want already exists, but not in the form you'd like to see it. That's where software like GrADS comes in. Put out by the Institute of Global Atmosphere and Society's Center for Ocean-Land-Atmosphere Studies, GrADS claims to be an 'interactive desktop tool that is used for easy access, manipulation, and visualization of earth science data.' I agree with all except 'easy.' I run a version of GrADS on my server in order to produce localized forecast graphics like this that wouldn't otherwise be available. Yes, looking at satellite imagery and radar is a lot of fun... but the real fun is knowing what will be there before you look. And, astoundingly enough, we are significantly more accurate (and I get assaulted significantly less often at the grocery store) than even a few years ago.
It has to do with the way fronts and pressure systems move...if there's a red sky at night, it means a high pressure front has moved in (means clear weather); a red sky at morning means just the opposite, an area of low pressure has moved in.
Here's a site with more on weather proverbs:
Weather Proverbs
NOAA's National Climatic Data Center has a lot of the raw data available, most of it for free (especially if you're coming from a .edu domain). Both US and international data.
Oh, I don't know... how about Environment Canada? You know, the place the weather network and every other forecasting service in the country gets their data...
weatheroffice.ec.gc.ca
The Meteorological Service of Canada has a web page at:
http://weatheroffice.ec.gc.ca/canada_e.html . The going was a little rough there for a while (we don't have the resources of the big media outlets to make it look pretty) but it is getting better all the time. It is also the place where the information is guaranteed to be up to date.
Watch out about the images under "weather charts". They are still the large, old-style monochromatic images. (That will change, eventually, to smaller colour images).
Even if you don't want to run a climate model, try putting XPlanet on your background, and get the updated cloud images every 3 hours.
It's a great way to stay informed about what's happening weather-wise around you, and you'll be able to watch the weather-forecasts with an "I guessed as much", from being constantly aware of the cloud pictures.
When the Blizzard of '78 hit, you had, in essence, an inland hurricane. Two low pressure systems merged, producing a single system that was deeper than either of the original two. It then pulled moisture from the south, and cold air from the north. Voila, hurricane over land.
The origin can be traced to the Bible (possibly before, but don't know of any reference):
Matthew 16:3:
He answered and said unto them, "When it is evening, ye say, 'It will be fair
weather: for the sky is red.'
And in the morning, 'It will be foul weather today: for the sky is red and
lowring.'"
Not only can the colour of the sky be affected by pressure fronts as pointed out in other places, but it can also indicate the movement of cold fronts. I suppose the 'sailor version' is more well known in the US because almost the entire population imigrated by sea... but the 'shepherd version' which is more well known in Europe, will pervade agricultural commuities more.
"It's a great job... a magnificent physics puzzle, solvable with high level math and some acquired skill."
I hate to cast a damp towel on this, but personally, I find this is to be silly self-promotional drivel. What Weather forecasters won't tell you is that anything beyond a 3-5 day forecast is just a guess.
So what? There are a lot of fields in science where most of our knowledge is about making accurate guesses and then seeing how well they fit the reality. It's not just about weather, the same tools can then be used on other complicated dynamic systems.
Their accuracy rates beyond this period go down below 50%; which means that flipping a coin is more accurate.
Really? I'd hardly call predicting the weather a simple case of true-or-false. Otherwise they could simply always give the exact opposite result that the complicated computer simulation gives and arrive at over 50% accuracy.
Though there are some places (like Ireland, I've heard tell) where simply predicting rain every day will be correct 80% of the time.
You are better off saving your CPU cycles for something more valuable, like Primenet (www.mersenne.org), IMHO.
Computer scientists and their everlasting silly infatuation with primes... There are other important research areas, you know.
I run a Davis VantagePro Weather station. It relays data from a sensor cluster up on my roof to a console in my computer room via 900MHz radio. Then Davis' WeatherLink software submists it to weatherunderground and to my own website.
TAFs (as forecasts) may be accessed here.
METARs (as reports) there.
The only thing you have to know is the four letter ICAO location of your closest airport.
Go there to find it out, and then... you'll have to decypher the stuff. Have fun !
I know a PHP package that does it quite well.
Here's a picture from my street at 11:00 AM from back in late October. Orangish-brownish, although I think this had more to do with the San Diego wildfires burning 10 miles away moreso than weather fronts. ;-)
I could not justify my existence if I were a turkey farmer. Would I terminate myself? Undoubtably, yes.
Actually, Lorenz's first paper on the subject "Deterministic Nonperiodic Flow" was motivated by computer simulations he ran using a set of three highly coupled, non-linear differential equations that represented a simple weather model. The solutions to those equations will yield the very standard butterfly-wing graph, as well as exhibit sensitive dependence. It was on the basis of this model that Lorenz several years later coined the famous "butterfly effect" term. So, it was initially a weather model, and that's what my post referred to.
I'm not sure what the equivalent saying would be for SF. Probably something pithy about five to seven fog cycles, which is the biggest hazard on the bay.
The difference between Canada and the USA is that in Canada healthcare is a right and gun ownership is a privilege.
Official Site
Short Blurb from Time Magazine
Descriptive Article (with pictures)
Details Regarding its Supercomputer Status
spend time outside
My grandfather taught me to watch the birds. They get nervous when the weather is about to change.
Smell the air, look at the sky, examine the clouds, and feel the wind, the temperature, and the humidity.
I can almost always tell whether it's going to rain or not. In central Illinois, that's quite a trick.
sigs, as if you care.
Sorry, have to plug my own site here... :)
I know a website that does it all for you
"Shepherd" is a verb here, genius...
The United States of America: We do what we must because we can.
That gibberish is rated a 4?
:P
The "red sky" phenomenon is caused primarly by high straitform clouds reflecting the reddened sunlight at, well you know, sunrise and sunset. It has nothing to do with "high pressure fronts" whatever
the heck those are. Must be a Penn State graduate.
I've seen a lot of beautiful red sunrises with good weather afterward and spectacular red sunsets with deterioring weather following after midnight.
If you have a degree in Meteorology or Atmospheric Science (basically you took all the hard classes with Calculus) then you're a Meteorologist.
These days, you can get a broadcast Meteorolgy degree from Mississippi State or SUNY Albany, and become an weatherman without all the tough classes.
The logo you're talking about is the
AMS Seal of Approval.