Beachy Weather
The weatherman don't know which way the wind blows.
With seven family members, we’ve confined our summer vacations to places within reasonable driving distance where we can rent an entire house. The last three years, we’ve gone to Kill Devil Hills in North Carolina’s Outer Banks.
We were pretty lucky the last two years, with decent weather almost daily. Less so this year, with rain throughout the day for much of the trip, presumably a byproduct of the tropical storm off Florida’s coast. That’s always a risk with a beach vacation.
What’s been especially bizarre, though, is the wild unpredictability of the weather. We’re in an age where the weather app on our phones provides hyper-specific forecasts like “light rain starting in 13 minutes” or “rain ends in 9 minutes,” and yet the hourly forecast has changed radically three times in the two and a half hours I’ve been up this morning. I’m not talking about the forecast changing from “40% chance of rain at 3 pm” to “70% chance of rain at 2 pm” or the like. Rather, it’ll go from predicting steady rain from 9 am to 5 pm to predicting no rain between 9 am and 3 pm to predicting thunderstorms from noon to 3. It’s been doing that since Wednesday.
While I always check the 10-day forecast for loose planning purposes, I don’t expect weather reports to be particularly accurate more than two or three days out. And, with tropical storms and hurricanes, I fully expect fluctuations even within the 24-hour forecast. Butterfly effects and all that.
But forecasts that change this wildly, this often are beyond useless.* I’d be better off just looking at the sky or asking an old farmer how his knees feel. Yet I reflexively keep checking the report as though they have some idea what the weather is going to do.
__________
*And, no, JKB, this doesn’t mean climate change is a hoax.
Here’s hoping for a great vacation for you and your family.
Seconded – have a great trip!
Here in SC, the weather has been something wet all week. Drizzle all the way to so hard I can’t see the mailbox from the porch.
We love the Outer Banks, although we usually stay in Corolla if we are meeting our friends from MD, or Hatteras if we get to choose. We have been the only people on the beach at Hatteras in the middle of the summer.
Hope the rest of the vacation is less rainy.
Competition seeks an edge, a differentiator.
So we get this “rain ends in 13 minutes” garbage.
Somebody in marketing realized that nobody expects the weather forecast to be accurate, so they differentiate on precision, with no regard to accuracy.
Precision instead of accuracy. Or at least the illusion of precision. It’s good enough to sell the phone, after which nobody cares.
@BugManDan: We’re actually headed up to Corolla (for the first time) Saturday. I decided that one week, bookended by miserable Saturday traffic, was just too short and we booked too late to get two weeks in any VRBO or AirBnB, so wound up booking back-t0-backs. We’ll see how it goes but the weather forecast (for what little it’s worth!) isn’t looking great.
I cant remember the exact statistic, but *supposedly* weather forecasts are as accurate now at 10 days as they used to be in the 1980s at like 3 days.
I don’t believe a word of it. I’ve stood in pouring rain while looking at a phone that says 0% chance all day. Yes, ZERO percent! That’s unfathomably confident. Sorry, but a forecast should never ever say 0 or 100%.
If you simply predict tomorrow will be like today, you’re actually not that much less accurate than a professional forecast. And I’m not saying this to denigrate the weather people. Modeling this is extraordinarily difficult, even if you had sensors everywhere and almost infinite computing power.
I figured that sooner or later OTB would get around to bitching about the weather.
@Franklin: As a guy who drove a convertible for a number of years—and would pretty much drive with the top down no matter how hot or cold if it wasn’t raining—I had that happen soooo many times with a 45 minute commute.
@CSK: Ha. Mostly, I’m just confuzzled that the forecasting is THIS bad. It’s changed like six more times since I posted. Indeed, we were all loaded up to walk to the beach when we heard thunder (not in the forecast!) and promptly walked back in. I’d rather them just put up a ¯\_(ツ)_/ emoji instead of a forecast if the conditions are that unpredictable.
Which weather app are you using and do you know where the forecast data is coming from?
For example, Accuweather uses it’s own model, some use NWS data but that often is for a wider area. And if what you are seeing there are rain cells, where those go exactly is hard to predict.
Here in Colorado during the summer we usually have storms roll in from the foothills in the afternoon. Where they form and hit really isn’t predictable until they are already formed. We had a quick sprinkle here yesterday while our friends two miles to the south got pounded with ping pong sized hail. We know the threat of a storm is present and plan accordingly.
I hope you have a lovely vacation!
A friend told me that a lot of historical weather data are collected by commercial flights, and when covid grounded/reduced the overall number of flights the volume of data collected dropped too. So, there’s a hole in the data set being used.
I have no idea if this is true or not, but if so, chalk it up to another thing to blame on the pandemic…!
@Franklin: I used to know an actual National Weather Service meteorologist and FWIW he was frustrated by the fact that although the NWS had all kinds of information at hand, they couldn’t get that directly to the public (this was before the interwebs) and the TV and Newspaper weather services did a terrible job of explaining what the forecast was saying (all while pretending the forecast was theirs and not the NWS). For example, if they predict a 50% chance of rain in an area, they count it successful if at some point during the day it rained in 40-60% of the area and was dry in the remaining area. All too often that just got translated as “Rain tomorrow! [Cute rubber ducky graphic]”.
I know that more than once, when I used…(I can’t remember the name but Apple bought it) it would say, “Rain in 10 minutes” and it never rained at my location, but if I was down at the harbor with a wide view I could see it was raining nearby.
@James Joyner: Yeah, this is weather app salesmanship. We’re up in Corolla (leaving tomorrow morning, traffic willing), have had the same “Rain in 9 minutes! Rain ending!” nonsense. There was a North-running Gulf system that overtook an East-running front and created a lot of pop-up rain between the two fronts. As a bonus, there are now like a dozen low pressure and high pressure bumps around this convergence – it’s lumpy “fronts” like I’ve never seen before. That’s making for, I think, a lot of unpredictability about where exactly the rain will appear.
I use NOAA and flight forecasts to get reasonable information on probabilities, but apps that sell you on precision are only good when the rain lines are distinct.
@Andy: I just use iPhone’s Weather app, which uses NWS data. ((It was fed by the Weather Channel until recently.)
I read Nate Silver’s book The Signal and the Noise some years ago. Interesting. He made a living playing on line poker until too many players got as good as he was. He noted that weather forecasters tend to forecast “wet”. The theory being that people who’s picnic is rained on after you said dry get angrier than people who unnecessarily canceled because you said rain and it didn’t.
@ptfe:
If the Weather Channel app, which I use, has hourly data that says 10% chance of rain every hour for the next twelve, does that mean a 10% chance of rain some time today or a 120% chance? I read somewhere that they put a lot of research into how to state probabilities that feel right to the average user. Which is to say they have no precise meaning.
Precise here meaning precise definition. Numerically precise is a different matter. As @Tony W: notes, engineers make a distinction between accuracy and precision. A thermometer can be precise to 0.1 degrees, but only accurate to +/- 2 degrees.
@CSK:
Everybody talks about the weather but nobody does anything about it.
@MarkedMan:
I think the app was Dark Sky. I use android and lost access to it when Apple bought it. And then, I think Apple integrated Dark Sky’s tech into their in-house weather app and took DS off the app store.
I use Carrot. Not because it is more accurate (or precise), but because it is pretty funny. By default, it calls you “meatbag.” Upon opening it today, it greeted me with:
Who doesn’t like that in their weather forecast?
You can set its aggression level. I don’t know the lowest options, but the two most aggressive are homicidal and overkill (includes profanity). You can also set your politics as liberal, conservative, centrist, libertarian, communist, or apolitical.
@Bill Jempty:
Well, as we say here in New England, wait 15 minutes and it’ll change.
@gVOR10:
My understanding is, at least for the NWS, the usual meaning for “10% chance of rain” is 10% areal coverage. That is, the forecaster predicts that 10% of the forecast area will get some rain during the forecast period. Reading the NWS forecast discussion is often useful. Eg, where I am, the forecast may say 20% chance of rain while the discussion says they expect rain to be confined to the mountains and not spread out over the plains. I’m glad I don’t have to do forecasts for my NWS area (north central and much of northeast Colorado). The mountains/plains interactions get downright weird sometimes.
Corolla was barely a strip mall when my family went there in the late ‘90s. My kids go there with their mom’s family these days and they tell me it’s quite built up.
Corolla was barely a strip mall when my family went there in the late ‘90s. My kids go there with their mom’s family these days and they tell me it’s quite built up.
@Kurtz: it was Dark sky. I used it despite seeing a comparison that showed it ranked pretty low in accuracy. So why did I use it? I have no idea. But when I actually needed an actual weather prediction for something important, I went to weather.gov
@CSK:.. Well, as we say here in _____*, wait 15 minutes and it’ll change.
*Insert name of any of the 300+ cities and towns in the 14 states where I worked the telephone lines over 35 years. I can’t speak for the other 11 States that I’ve visited. Only stayed long enough to hear “Have a day.” as I beat it out of town.
@Mister Bluster:
Oh, hell, they probably say it at the North Pole.
Surely it means the opposite, with the climate changing so quickly that the weather forecasts cannot keep up.
@ptfe: I dunno. I’ve never needed to know “rain in 9 minutes,” so I just ignore that feature on my phone’s main screen. First world issue.
@CSK: Where I grew up (Seattle) the line goes “Don’t like the weather? Come back in 1o minutes.” That and “Seattle Rain Festival: July 1-June 30.”
@CSK:
Here along the Colorado Front Range, I take a somewhat longer perspective: “We have four seasons here, and we’re not afraid to use them all in any given week.”
@Bill Jempty:
Well, collectively we are, but not in ways that make people happy. For example, we’re working on “There’s just too damned much rain in the desert Southwest.”
The “rain in 9 minutes” is weather radar stuff.
Weather radar is available on multiple apps, so you can see where the showers are and where they are moving…and cut out the middleman.
@Andy: I will note that the Apple and TWC are giving me significantly different forecasts, for whatever reason, even though I assume they’re both using NWS data.
@Tony W:
I’m thinking how many times I’ve seen rain on one side of thestreet and nothing on the other. Obviously the edge of the rainstorm has to be somewhere, plus clouds get moved by winds all the time.
So saying rain will begin in a specific area in a given time strikes me more as ludicrous than hubris.
@James Joyner:
I think that Apple uses whatever forecasting model Dark Sky used. When it was independent, Dark Sky relied on multiple sources for raw data, including NWS then applied its own algorithms to produce their forecast.
I don’t know for sure, but it’s a safe guess that Apple purchased Dark Sky at least in part for the machine learning techniques the latter developed for its forecasts.
Oops wrong thread.
@Kathy: Especially true down in Oz. I visited Darwin at one point and it was insane watching a torrential downpour hit one side of a street while the other side would be totally dry.
….how does it DO that?!
The Rain in Spain Stays Mainly on the Plain
Wasn’t someone there recently? Reynolds? Maybe we can get a confirmation on this.