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Modern Weather Forecasts Are Stunningly Accurate (theatlantic.com)
An anonymous reader quotes a report from The Atlantic: Meteorologists have never gotten a shiny magazine cover or a brooding Aaron Sorkin film, and the weather-research hub of Norman, Oklahoma, is rarely mentioned in the same breath as Palo Alto. But over the past few decades, scientists have gotten significantly -- even staggeringly -- better at predicting the weather. How much better? "A modern five-day forecast is as accurate as a one-day forecast was in 1980," says a new paper, published last week in the journal Science. "Useful forecasts now reach nine to 10 days into the future." "Modern 72-hour predictions of hurricane tracks are more accurate than 24-hour forecasts were 40 years ago," the authors write. The federal government now predicts storm surge, stream level, and the likelihood of drought. It has also gotten better at talking about its forecasts: As I wrote in 2017, the National Weather Service has dropped professional jargon in favor of clear, direct, and everyday language. "Everybody's improving, and they're improving a lot," says Richard Alley, an author of the paper and a geoscientist at Penn State.
Understanding months-long events like El Niño, for instance, has allowed meteorologists to go beyond the seven-day forecast. Alley, the Penn State professor, says that he is awed by the new models. Well-studied features of Earth's climate -- like the temperate Gulf Stream in the Atlantic Ocean -- emerge in computer models, even though developers have written code that only mimics basic physics. We are now surrounded by the products of these miraculous models. In 2009, a back-of-the-envelope study estimated that U.S. adults check the weather forecast about 300 billion times per year. Perhaps in all that checking we have forgotten how strange the forecast is, how almost supernatural it is that people can describe the weather before it happens. More than 1,000 years ago, the Spanish archbishop Agobard of Lyon argued that no witch could control the weather because only God could understand it. "Man does not know the paths of the clouds, nor their perfect knowledges," he wrote. He cited the Book of Job for authority, which asks: "Dost thou know when God caused the light of his cloud to shine? Dost thou know the balancings of the clouds ?"
Understanding months-long events like El Niño, for instance, has allowed meteorologists to go beyond the seven-day forecast. Alley, the Penn State professor, says that he is awed by the new models. Well-studied features of Earth's climate -- like the temperate Gulf Stream in the Atlantic Ocean -- emerge in computer models, even though developers have written code that only mimics basic physics. We are now surrounded by the products of these miraculous models. In 2009, a back-of-the-envelope study estimated that U.S. adults check the weather forecast about 300 billion times per year. Perhaps in all that checking we have forgotten how strange the forecast is, how almost supernatural it is that people can describe the weather before it happens. More than 1,000 years ago, the Spanish archbishop Agobard of Lyon argued that no witch could control the weather because only God could understand it. "Man does not know the paths of the clouds, nor their perfect knowledges," he wrote. He cited the Book of Job for authority, which asks: "Dost thou know when God caused the light of his cloud to shine? Dost thou know the balancings of the clouds ?"
I do not doubt that significant progress has been made in modeling weather and predicting some aspects of future weather. But so far this only changed weather forecasts from being "mostly random, not better than just predicting that tomorrow's weather will be just the same as today's weather" into the current "we can state some trend that is reasonably likely to be correct for the next few days". I can still read weather forecasts from yesterday evening in the news that say "0% probability of precipitation today for the city I live in", while I see rain falling outside the window.
"Stunningly accurate" would be a whole different thing, like the forecast being able to tell me "rain will start to fall at my location from 10:34h to 11:27h tomorrow" - and that they very much still cannot.
Said the weather was 29C and the thermometer outside said 34C in the shade...yeah....stunningly accurate.
Here in Norway we have learned to depend upon https://yr.no/ which provides both short-term (2+ days) and long-term forecasts:
When the short-term forecast states that it will be 0.5 to 0.8 mm rain (or snow equivalent) between 10:00 and 11:00 tomorrow, and that it will clear up starting at 13:00, this is very likely to be correct. If it isn't exactly right it is usually because the changes happen a little bit before or after the maximum likelihood prediction.
The presentation of the weather data is so good that many people in our neighboring countries have started to use YR instead of their local weather service.
Terje
"almost all programming can be viewed as an exercise in caching"
I wish every weather service published a graph that showed the progress of the correlation between their 1 to 7 day forecasts and what actually happened, somewhat like the graph for hurricane tracks in the referenced article. Published confidence levels would also help to know how locked-in a prediction was.
My experience has been that forecasts a day or two ahead are amazingly accurate, but that you can't rely on forecasts a week out for scheduling an important event.
With their C-x M-c M-butterfly.
A big part of this is that forecasts and current conditions have vastly smaller location granularity than in the past. In 1980, for a given state, you'd be lucky to obtain specific forecasts for maybe 10-15 large cities in the entire state (less for smaller states). I'm sure most of you have seen weather where it rained at your house, but just a few blocks down the street they didn't get rain at all. When your forecast granularity is representative of hundreds of square miles, then of course you can never be very accurate for that entire area.
Now the forecast is latitude and longitude based, and the precision is vastly finer. That alone increases the accuracy tremendously. Weather forecasts now are also down to "minutely" (as in hourly or daily) time spans. Again, same thing. When your forecast broke the entire day into "night" and "day" periods, you can never be very accurate. Most weather apps now forecast what will happen in the next hour down to the minute ("Light rain will begin in around 12 minutes"). It's easy to be accurate when you can forecast such a small time into the future.
There are many reasons weather is more accurate now, everything from the lead time (if your forecast has to be in to the newspaper before 5 AM so it can meet the press deadline, then you're accuracy will be reduced compared to a forecast calculated the moment it is asked for), to the technology that allows people to ask for and view data when they want it for a very specific area.
Better known as 318230.
Nothing more than a whore you are stating a lie like this. They haven't been within 10 degrees of being accurate this week with the colds and snows. Give us a break and rather than living a life of wishful thinking and dreams of a greater world live in the real one for a change.
We have a lot more data and we have a lot better understanding of the correlation betweeen past and present conditions around the world and future contitions at any given spot than we did 40 years ago.
Yes, there has been a huge improvement.
No, I am not surprised.
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
And how can the be accurate when they keep making up stuffs like weather bomb...
Example: last week when the Twin Cities was predicted to get 8-12 inches of snow and got 3-4.
Sunningly accurate weather forecasts? Bull. I'm a keen motorbiker and an accurate weather forecast would be a god send. In winter, my life depends on wearing the right gear for the right weather. I have lost count of the number of times that a weather forecast has said it will be dry only to be riding through pissing rain within the hour.
Here in Arizona they are consistently wrong. More often wrong than right.
I traveled with my family for a week in Paris last October. The forecast basically said it will be rainy all week and changed to sunny all week (which turned out to be correct) just one day ahead of our arrival. Not exactly what I'd call "stunningly accurate".
So the longer range forecasts are more accurate than ever. Why cut off at 10 days, then, and not 11? Sure, 10 is a very human number, but there's no scientific reason to assume it's a natural cutoff in reliability. Why not use the current methods for a 10-day forecast and extend it out to 100 days. Then study the accuracy and see if there's a sudden drop-off, and cut off the published forecasts just short of that. It would also be interesting if they would publish a confidence rating on the forecasts, so that we could see how it drops off as the time increases.
With the Internet, there's no space limit, so have the soft mushy short version that most people will stop with, but also put out more detailed information for people who really want to understand.
There's also the fact that there's more weather stations out there. When a citizen can buy a relatively inexpensive weather station and hook it to the internet, never mind all the cellphones with temperature, pressure, and humidity sensors, things are bound to improve.
I'm gonna call bullshit on this one. MAJOR bullshit.
I get my forecasts from https://www.theweathernetwork.com/, and if forecasts were now as accurate as this article claims, there'd be no reason for a 5-day forecast to change 10 times by the time we reach that day.
I can't point anyone to a resource (that I know of) that can be used to look it up, simply because I don't write down the numbers, and the site doesn't let you go back to older forecasts, but I can guarantee that even the 24-hour forecasts are way off. 2 weeks ago, in the midst of a full week of -10C (and lower) temperatures, it was forecast that we'd see +6C the coming Wednesday. I watched that forecast for days, they stuck with it for a while, then on the day before (and **even on that same day**), they still called for +4C, and by the time everything was said and done, the temperature *never* actually rose above 0 on that Wednesday.
This is just one example, but I swear I see something like this EVERY. SINGLE. WEEK.
If they're still off by more than 4C within less than a day of their forecast, please define what "stunningly accurate" actually means.
[Old fart rant]
I'm absolutely convinced forecasts from 10+ years ago used to be *way* more accurate than they are today.
I am stunned of how wrong they get it. Sometimes they can't even agree with the current data, like "we forecast a maximum of 22C for today, current temperature 23.5". I'm always thinking of the first part from "Two Man in a Boat" when they get it (once again) spectacularly wrong.
To who?
I see lots of people claiming they know better than the study but it doesnâ(TM)t seem to be based on any rigorous research.
The issue with complex modelling has traditionally been in computational power vs usefulness. With weather modelling, you can generate a very accurate prediction a week ahead. Problem with it was in 1980, you needed so much computational power, you would get this "forecast" finally calculated a few years after it was relevant. Computational power to do it in time frame that was useful was simply not there.
Today it is there, so meteorologists can get calculations for days ahead done in time frame which is useful, i.e. before the events they're trying to predict occur, rather than long after.
Models improved too, but most of that improvement has actually been "add even more detail to do something with all the increasing computational power".
What do you expect? In this so called age of "science" when hoaxes like global warming and evolution are pushed by so called "scientists" who are basically just morons with liberal agendas, why would you be surprised that no one beleves them any more?
He that observeth the wind shall not sow; and he that regardeth the clouds shall not reap. - Ecclesiastes 11:4-6
In 2016, in the mid-Atlantic region, we had a mild winter. There was one snow event only - but that event dumped about 33-36 inches in the Baltimore/DC metro region. That event was informally called Snowzilla, and it was predicted to the tee, 8 days out. That was probably the most amazing forecast achievement I've seen.
Of course, the meteorologists still screw it up, sometimes fantastically. But other times, they knock it out of the park.
"Cold front will arrive next Tuesday morning and lows will be in the teens and highs in the 30s by Thursday afternoon."
That's funny that you put it that way, because that's how they USED (~ 1980s) to predict the temperature: in the lower 70s, mid-20s, etc. Nowadays, all the TV stations here in Chicago give impossibly exact numbers: 32 for the high, 14 for the low, etc.
Weather forecasting hasn't got better, at all.
My Gran, rest her soul, was always far better at weather than any bloody meteorologist and that over her life of 95 years. Was she perfect? No, but a lot more use than any bloody meteorologist.
Add computers and satellites and they suddenly think they're all bloody geniuses.I'd actually say they're worse or the same. Probably get better results reading entrails.
just to claim their climate change hoax is real. therefore their models must first be flawless, what they start claiming now.
fucking manipulations by little monkeys who think they have what it takes to be brainy.
At 3am the morning before, forecasters calling for an inch of snow.
Later that same day: A foot of snow.
Or what about the snow on no forecast that suddenly arrives one day.
Forecasts are better to be sure but to call them "stunningly accurate" is laughable.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
On an aggregate we've come a long way. Not news... The more detailed the harder it is. You can improve a skill overall but make imperceptible improvements at components of it or even go backwards at them.
The models are are more detailed now and they get results faster so they can do better now than in the past; as well as constantly update with new data but they do not yet model all the local impacts or report it to specific locations. 100% accurate will always be wrong for people physically located between boundaries (or if people move around) depending on the resolution of the regions.
The old weather man prof they had on PBS was talking about changes over time. They thought there was some heat island with the Cities but only now do they have detailed trend data on it being as high as 10F warmer (but 8F more common.) They are not yet modeling the impact of the twin cities, landscape, big fires, or reporting based on your planned GPS route for the next 5 days. That is coming...
Democracy Now! - uncensored, anti-establishment news
"Late night and early morning low clouds and fog"
Anybody wanna tell me where you hear that every day?
However I concur with the article. Weather, especially hurricane forecasting is top notch. It would be a real shame if anything happened to it on the whim of some crazy politician.
“He’s not deformed, he’s just drunk!”
He doesn't mention that God answers the question by admitting that he is a fertility god invented by a slew of religions before the bible.
I'd say they are correct about 75% of the time.
Here in Montreal I have the feeling the weather predictions were far more accurate in the 1990s and 2000s. Lately they have been consistently wrong summer and winter. They keep forecasting major snowfalls and nothing happens.
Mostly random stuff.
perhaps they should drop the title "meteorologist".
these are the same scientists telling us global warming and evolution are "facts"
More than 1,000 years ago, the Spanish archbishop Agobard of Lyon argued that no witch could control the weather because only God could understand it.
Some people complain Harry Potter is evil because of "magic". Same complaint for other shows.
Yet they go home, wave their hands, and suddenly night turns to day (hit the light power switch.)
Their house is somehow cool in the Dog Days of summer. (AC)
They open a door, pull out cold food that was cut/killed weeks ago, and it's still good. They put it in a different box, and 2 minutes later it's hot. (fridge, microwave.)
They handle a small box and suddenly demon voices imitating their friends are responding to them. (cell phone.)
They handle a different box and far-away scenes and audio appear, some that don't exist. (TV)
Noisy flying demons fly thru the clouds to induce rain. (Cloud seeding)
Be careful flinging around the word magic, because soon it might be everyday common knowledge. Burning all the witches might leave you stuck longer in the dark ages, struggling to survive.
OTOH, some witches might open up Pandora's box, never mind SkyNet.
If the universe is someone's simulation -- does that mean the stars are just stuck pixels?
Forecasts may be more accurate, however many weather institutions like The Weather Channel have succumbed to the perceived demand for sensationalism over science. You are more likely to view video of homes being destroyed by hurricane Andrew or see Jim Cantore being blown over ad nauseum rather than get valuable empirical data or helpful information like what local shelters are open in the event of a storm.
I spoke to a guy at the UK met office about this in the 90s and he explained how they were basically compute limited. They run a number of sims with randomized perturbations at the start and see which outcomes are the most common across perturbations. They were using all their Crays full whack and that's what determined and limited the accuracy of the results. 30 years later, compute power is somewhat cheaper and my desktop is faster than one of those Crays.
I should use this sig to advertise my book ISBN-13 : 978-1501515132.
Changing topics slightly but if you look at the pollen / allergy state (not forecast) from 5 sites for your city you will get 5 entirely different reports ... and that is for "current conditions"... "mold" especially seem to be just a random number they generate. WTF?
I am not in countries neighbouring Norway. In fact, I am an ocean away, in Canada, but I do use YR.no.
First, it powers the XFCE Weather Plugin. Some of us still use Linux for the desktop (remember that?), unlike many on Slashdot.
Second, the web site loads fast, and does not use AJAX and other abominable practices (as opposed to Canada's TWN and Wunderground).
Third, the UI is simple and to the point.
Fourth, they have a API that can be used from many applications (one is the XFCE Weather plugin), including Home Assistant.
Fifth, they provide a cloud forecast, which is useful for astronomy.
Accuracy is good for temperature and precipitation. For clouds, it is not as accurate (but most of other services suffer from that too).
Thanks Norway ...
2bits.com, Inc: Drupal, WordPress, and LAMP performance tuning.
I find temperatures pretty accurate as far out as a few days. I think general regional forecasts are pretty good as well. Although I think beyond a few days accuracy goes down fast. I think long term predictions are not very useful, and the reason daily forecasts are better these days is that the data is updated more often. We have more weather satellites and ground based stations.
The forecasts are stunningly accurate, but getting it wrong is newsworthy and is remembered FAR longer than getting it right. Go and use ACTUAL FUCKING DATA not your asspull recollections and you will see how accurate they are.
Frigging armchair weathermen fucking piss me off.
Wrong. Just utterly wrong, but you are barking to show your fellows how smart you are, smarter than those book learnin' spectacle wearers. Moron.
Just because you hate science because it refuses your ignorant religion and doesn't pander to your political ideology it doesn't make AGW either a hoax or a liberal agenda, fuckwit.
Or are you always doing this when you're safe from consequences and can run to daddy to protect you?
Know what else saved your grandpappy from an early grave? He wasn't an asshole to people. Give it a go one decade. It'll extend your life by years.
... all from serious national institutes in Europe, for the next days in Berlin: https://kachelmannwetter.com/d...
As you can see, only 3 days into the future the predicted temperatures vary by 4C and the predicted precipitation (tab labeled "Niederschlag")looks almost randomly different between the models.
This is all but "stunningly accurate".
The issue you may be having is that the forecast is accurate but the news aggregator that is presenting it to you doesn't understand it and misrepresents it. In particular the 'x% probability of rain' element is widely misunderstood. '40% chance of rain' means 40% chance of raining at any point during the given period within the catchment area, and not, as popularly interpreted, including by news papers, as '40% of it raining at the moment the given time period specified in all locations in the catchment area'.
At the end of the time period, that should read.
For completeness, it might mean that the chance of it raining in any given hour of the time period, including the one at the end of the period, might be as low as, say, 5%, even though rain on that day at some point is fairly likely. It's relatively counterintuitive for most people, even when newspapers report it correctly, and they might want to consider changing the system.
E.g. if any hour rain has a totally independent chance of 5%, the chance of rain during 24 hours is 1-(0.95)^24, or 70%. Of course, if it is raining at 3pm, it's often raining at 4pm - i.e. it's not independent. But saying there's a 70% chance of rain over 24 hours is useful if you are a farmer wondering if it's worth running the irrigation system or harvesting what that day.
At a 99.5% chance of no rain (0% of rain when rounded) per hour there's still an 11% of chance it will rain that day.
This is the second article that's fake. The first was about the "smart" anti-vaxxers. You guys need to watch what you're posting here.
20 years go, models were based on surface weather stations, a few hundred points of data for a typical country. Satellite data was mostly pretty pictures for humans to gawk at. Now Satellite data assimilated into the analsysis that is used for computerized forecasts. Much higher resolution data also. Satellite is now the main source of improvement. weather RADAR data is currently also pretty pictures mostly. *nowcasting* is about assimilating RADAR which is similar or higher res than typical satellite data.
My wife and I spend a lot of weekends hiking. I watch weather forecasts to determine plans (including camping plans) days or even a week in advance. Is it going to be sunny or heavy rain? Modern weather forecasts are better than flipping a coin, but not by much. I usually end up looking at weather radar a day in advance (for day trips) and make my own forecast.
[Insert pithy quote here]
I'll be stunned when NOAA stops showing a current temp of 35 F, then immediately below it claiming a high of 32 for the day.... You would think they would at least adjust the prediction so it would match actual data...
Here's how weather forecasts for the next day or two are stunningly more accurate.
Next week's story:
Given how precise 2 day weather forecasts have become since 1980, the national weather
bureau hundred year forecast is a rise in average temperatures of 1.5 F and a rise in sea
levels of 1.75 feet affecting 4% of the continental USA's population.....
Easy to see the jack-hammering of we're 99.999% accurate in ultra long term predictions, for that emergency, a 25% capital tax is imposed on all citizens, permanent residents, non-profits and corporations with the $20 trillion proceeds being split 50/50 between bureaucrat pensions and building government owned solar farms.
Yesterday, the forecast for today here was sunny. This morning I'm looking out at ominous clouds and my phone just gave me a "rain shower coming" notification. Stunning. Simply stunning.