The Wi-Fi only works when it's raining

Let me see if I'm the first one to link to that classic story in the same series, "I cannot send email further than 500 miles"

http://www.ibiblio.org/harris/500milemail.html

Or the Magic/More Magic switch

http://www.catb.org/jargon/html/magic-story.html

It's fun when physical reality meets the abstract models that we have built in our heads of these machines.

Reminds me of an extremely similar case with a long distance microwave link at a mobile telecom provider in Australia that I worked for. They relied quite heavily on microwave link chains and this particular one was in northern Queensland where fixed lines were hard to find and no local engineers were locally present/aware of the changing environment.

Every week day + Saturday, from 7-3 the link would keep cutting out intermittently. Then work fine and the rest of the day and on Sunday… a crane, building a new residential building would operate during those hours right in the middle of the microwave path. Many weeks of theories and time wasted until someone had a chance to visit. :)

This is a bit ridiculous. How can you know that you have a ling of sight element to you network and not check that as the very first thing when you hear about rain effecting the wifi?

I had an experience like this once! My my laptop would inexplicably and intermittently stop connecting to the internet.

It turned out my bluetooth headset was using the same band as the wifi but I only figured this out after a few months and a replaced wifi card. I wouldn't wish that experience on my worst enemy.

I have a hard time believing this. Wifi can go through multiple walls. And if these were directional P2P links, they can easily go through and even around trees, I've deployed them in the past and they don't need perfect line of sight.

Granted the equipment could have been cheap, but this sounds questionable. He's asserting that the a few leaves at the top of a tree were blocking it when it wasn't raining? Idk.

FYI this being part of "April Cools" series heavily implies it's not a real tech issue but a riff on the "We can only send an email within 500 km" / "Can't print on Tuesdays" kind of articles.

TIL about Fresnel Zones!

Interestingly, objects outside the straight line between antennas can still cause interference! For best signal quality, the Fresnel zone between the antennas should be clear of obstructions. But perfection isn't achievable in practice, so RF equipment like Wi-Fi uses techniques like error-correcting codes so that it can still work without a perfectly clear Fresnel zone.

I wonder if other waves like pressure/audio waves also have a similar effect.

[1] - https://en.wikipedia.org/wiki/Fresnel_zone

(Side note, is this story old? 802.11n isn't particularly new enough to upgrade to.)

While we're on the subject: I still can't solve this and thought you'd either laugh or you are the only people who know what I'm going through :)

I have some fancy Asus Mesh wifi routers at home. I sit next to the cable modem and one mesh endpoint. My wife sits upstairs. there's an upstairs mesh endpoint but I think neither of us are usually connected to it (mostly serves to extend our connection to go to yard). But when my wife gets up from her desk and walks through our hallway (closer to the non often used mesh endpoint) our internet drops for a bit. My only guess is that the endpoints get mad at meat being in between their back haul? Anyone deal with this and figure out the solution?

The unusual internet setup is pretty important information to bury a few paragraphs in. Once that was explained it seemed like they should have started by checking nothing was blocking the antenna before tediously running around plugging the laptop into things and following cables and checking power supplies on the networking equipment?

Hindsight is 20/20 but I correctly guessed the ending as soon as that information was added.

From the article:

One such piece of magic new to 802.11n Wi-Fi is called "beamfoming"

That's not quite true. 802.1ln has MIMO (Multiple-Input Multiple-Output) processing, with "multiple" referring to the number of receiver and transmitter antennas. Beamforming is a special case of MIMO, and MIMO is a generalisation of beamforming.

In a "Line-of-Sight" channel with no reflectors, MIMO converges to a beamforming solution. Capacity is then limited by the ability for the rx/tx array to resolve each antenna in the tx/rz array: the diffraction limit.

In a "rich" channel, with reflectors, MIMO converges to a more complex solution, which takes advantage of the angular separation of the reflectors to resolve the individual rx/tx antennas, even if they are too close to each other to resolve with beamforming. Yes, counterintuitively MIMO capacity goes up as the channel become more complex/rich and less line-of-sight, whereas with just beamforming the capacity would typically go down.

You can sort of think of MIMO as being beamforming where beams are bouncing off widely spaced reflectors, but even that doesn't do it justice. In reality, each "beam" is replaced with complex wavefront ("mode") which is matched to the environment and each mode is orthogonal to the other.

Here's my own 500 mile email story. This happened to me about a year ago.

Just a normal day at the office when suddenly the internet drops out, except for my machine. Everyone else has a network connection, but no internet. Except for me, I can't reach devices on the local network, but I can reach anything outside.

Now, our network is not large or complicated. We have a consumer grade ONT and WiFi router provided by the ISP, and a big unmanaged ethernet switch. There's really nothing to go wrong here.

After some debugging, I notice that I have been assigned an IP address in my ISP's public block. Tracert seemed to show no local network between me and the WAN. It was as if the router had somehow connected my WiFi client directly to the ONT, bypassing the local network. That only barely makes sense, but it was my best guess so I condemned the router.

Next day, new router, same problem. I couldn't explain it. This time though, I didn't have an internet connection, but local network was reachable. Some sanity restored, ar least.

Turns out that our fiber line had been accidentally cut during construction work. Once the ISP fixed that, all was normal.

The question remains, how did I have internet connection through a severed fiber line? It's not likely that the router had a bizarre failure right before the line was cut. I suppose it's possible that Windows had sneakily connected me to some other WiFi network, but then why did I have a weird IP address?

I have no explanations

I own a Ford Focus and to this day I don't understand why sometimes the gear shifts make this cracking noise when decelerating to zero, but only when it is raining.

This reminds me of a taxi driver in Dubrovnik, Croatia who told me that his cel service would not work when it rained because the rain changed transmissions where he lived in a way that meant that his phone would connect to a cel tower one valley over which was in Bosnia where he didn't have a data plan.

Another classic:

Can log in while sitting down, can't log in when standing up.

I need to find the reference ...

Edit: OK, here's one version:

https://www.reddit.com/r/talesfromtechsupport/comments/3v52p...

These are great stories but awful experiences to live through. I am currently going through one right now. My wireless CarPlay connection shuts off whenever I drive past a particular highway section. It never happens anywhere else but this one area. There is nothing of note happening there (it's on a bridge over a lake) but just like clockwork, my entertainment system shuts down and refuses to connect. I have tried everything (reboots, firmware updates, wired connections, etc) to no avail.

The fix was easy: upgrade our hardware.

This made me smile. My brain autocompleted the fix to something like "help the neighbors trim their tree", but of course the fix is new hardware.

One of my most recent 'weird internet issues' was when I upgraded our 50mbit internet connection to 100Mbit and my laptop never really reached 100Mbit whereas my homelab easily got 100Mbit on speed tests.

It took me a while to realise the difference was that the homelab was physically connected and the laptop was using Wifi.

The laptop wifi was connected to the AP at ~1.2 Gbit and a different machine had the same issue. I decided to see what the internal network speed was and found that sending/receiving files to the homelab from a wifi device was also maxing out at ~90mbit.

This then steered me towards looking at the connection between the AP and the router, and I realised that the Wifi AP was connected at 100Mbit to the router instead of 1Gbit. Turned out the cheap CAT7 cable that I randomly used to connect Wifi to the router because it looked nicer than the existing cable was not actually a real CAT7 cable and only provided 100Mbit. Changing the cable fixed the issue! Out of paranoia I decided to replace all of my ethernet cables with decent quality ones.

I don't even remember where that 'fake' cable came from; probably from some random Aliexpress appliance that I bought at some point. I've had similar issues with USB cables that I've amassed, where I forget where they came from and only realise later that they barely fulfil their purpose.

Some years ago I put in a point to point wifi link for a family member, from house to garage "block". I specified a pair of Ubiquity Nanostations which are tiny, PoE powered and have a decent range.

The house end is inside a UK standard tiled roof - dense 3/4", allow for slat, so 1"+ thick and dense material.

The other end is 20m away (LoS) and external mounting was forbidden. The garage block has foil lined Kingspan style insulation. I managed to mount that end near enough to a skylight window to work OK. I then daisy-chained an access point off it.

All was fine until the sky light was replaced with a metalicised one. The signal just about worked until it rained which was enough to nobble it.

When it got annoying enough, me and said family member plotted and I rocked up when someone was absent for the weekend. I moved the garage station to the outside. It now looks like a bird box. I put up a real bird box at the other end too. The fake box would get baked in the sun but the real one is always shaded.

I had a similar experience about shipping pallet being fully loaded fixing server connectivity issues almost two decades ago: https://chir.ag/tech/?49

What kind of a tree is it?

I dislike calling this "magical thinking", just because the plausible causal relationship takes a little time to discover, it's not implausible at the outset.

In fact, the causal relationship between rain & wifi is taken as a given by the author:

If anything, rain makes wireless signal quality worse

It's not too surprising to discover a causal relationship between two things we already know are causally related.

Similar but opposite story:

20ish years ago I hung out in an IRC channel in which, during autumn/winter months, one person would frequently get disconnected and when he came back complained about foggy weather.

He had a laser line or sight connection. It could handle rain (with some degradation), but thick fog killed it.

I don't know if this is fake, but it could be true. I had a similar situation working for a WISP around 2010.

Every night, for about 10 minutes, the connections from our HQ to a relay tower became flaky. At the time we were using two Mikrotik 5GHz cards and some large antennas.

You could sit in front your computer and wait, a few minutes after the sunset, for the monitoring alerts start arriving. After a week trying everything, including changing hardware (to the same specs), I was very disappointed with the thing and got out to smoke around the sunset.

Then some huge lamps we had around the building switched on, based on a light sensor. Immediately I received the SMS alerts on my phone. I ran into the building, turned off the external lights and bingo: 0% packet loss.

It turns out that the building management had changed all of external lamps the week before, with new sodium-vapor bulbs. And for some reason, on the first 5 to 10 minutes with these lights on, it caused very high interference on the 5GHz band.

Changed the lamps, problem solved.

I had more thought of an issue regarding bad grounding (i.e. grounding rods dried out and only work properly when the earth is wet), but trees are even more unexpected.

Why does this sound like it was written by AI?

Once I had an Internet cable that stopped for a while whenever I turned on the microwave (understandable), and also stopped when started raining. The trickiest part was that it turned off just for a while and ONLY at the beginning of the rain.

I called the telecom company many times. They charge per visit in case no problem is found. I always had to explain the situation and ask the technician not to charge me and come when it started raining, a very hard thing to do because we cannot predict forecast and the network went down for 10 min only.

It does not seem a big problem, after all, I could just wait 10 minutes. After this happened multiple times a day every rainy week, making me lose meetings, work, server connections, etc... I had to patiently chase the telecom company and even ask for the personal phone numbers of technicians (to ping them when it was going to rain) until they finally found a solution.

I once had a Time Warner tech blame the moisture content of the air for impacting the copper cabling to explain outages at our apartment. This both makes more sense and, I suppose, is more interesting.

I had one recently - old Nintendo switch; worked fine when docked, couldn't get an internet connection on wifi.

Turns out it had been so long that the wifi MAC was picking up a DHCP address that was blocked at the firewall; the dock had its own MAC so it got a good address.

Reminds me of that old tale about a lady whose phone would not ring, and her dog would bark before the phone rang.

My Wifi doesn't work properly when it's raining, can be combine forces?

My guess was that the directional antennas were off by enough that it didn't work well in clear conditions, but the rain refracted the signal enough to work. The actual answer was better :D

Once upon a time, I owned a 1998 Volkswagen Wolfsburg Edition, a sleek and vibrant red car that turned heads wherever I went. As a city worker, I found it convenient to park my car at the train station and commute to work.

One particularly exhausting day, I trudged back from the train to the parking lot, eager to get home and unwind. As I approached my car, I noticed something peculiar—all the windows were missing. Panic gripped me, and I initially thought someone had vandalized my beloved vehicle. However, as I walked around the car, I couldn't find a single shard of glass on the ground. Upon closer inspection, I realized that the windows had simply been rolled down. Relief washed over me as I rolled them back up and drove home, putting the strange experience out of my mind.

Weeks passed, and the incident faded from my memory. Then, on a lazy Saturday morning, I sat on my back porch, sipping a hot cup of coffee and enjoying the tranquility of the day. Suddenly, the sky darkened, and a light rain began to fall. As the raindrops pattered against the roof, I heard an unexpected sound—the distinct whirring of car windows rolling down.

Perplexed, I set my coffee aside and hurried to the front of the house. To my astonishment, I found my Volkswagen's windows had mysteriously lowered themselves, allowing the rain to pour into the car's interior. It dawned on me that the windows' odd behavior must have been caused by a short circuit in the electrical system.

From that day on, I knew my 1998 Volkswagen Wolfsburg Edition was more than just a cool, bright red car—it had a quirky personality of its own, keeping me on my toes with its unexpected window antics.

I know of a case in the Caribbean where where a line of sight connection between two buildings of a bank was being interrupted by a tree from a competitor bank. They asked the competitor would they mind cutting the tree and the answer was sure for the small fee of 1 million, Third hand info but I did hear from a network guy I worked with.

My garage door opener works much better when it’s raining and also at night. I’m out case, our solar inverter (or one or more of the optimizers at the panels) creates enough noise to interfere.

I also believe our microwave is adding noise to the same circuit our WiFi router is on. Despite using 5GHz, WiFi is severely degraded whenever the microwave is on.

When I started reading this it seemed like “internet” and WiFi were being conflated, for example on our neighbourhood WhatsApp group there are often people asking “Is anyone else’s WiFi down?”, when what they should ideally be asking is if anyone else’s (fibre) internet is down. In such cases I internally frown a little, but leave it there.

Anyway, for the situation in this link, they actually have a WiFi bridge from their house to their office which has the connection to an ISP, so it is absolutely accurate to say the WiFi was down in this case.

When it's extremely windy, our office Internet or Wifi speed slows down. Haven't worked out why yet. We have fibre to the building, so it's unlikely the uplink. But you never know.

Reminds me of this story about repairing a large power line:

https://www.jwz.org/blog/2002/11/engineering-pornography/

My Wi-Fi used to work better in the rain because our signal was fairly weak as it was coming from the apartment behind the wall and the channels were generally crowded so (I assume) rain helped to at least insulate us from the networks in the buildings across the courtyard.

I recall there was a story about a computer mouse not working when it was sunny? It had to do with the sensor. I can't find it so I'm starting to doubt if that actually happened...

Edit: Found it: https://news.ycombinator.com/item?id=37585548

I was expecting a story about frolicking about in the sun. I'll settle for a hardware troubleshooting adventure.

The article briefly mentions that this was unbelievable because rain should make Wi-Fi worse not better.

That parallels my experience but I didn’t realize was commonly understood. I noticed that in the hot summer the Wi-Fi reception in my yard (IE, farther from the access point in the house) is worse. Eventually I decided that summer heat is really proxy for humidity and that it wasn’t unreasonable for high water concentration in the air to provide an obstacle to Wi-Fi signal.

This reminds me of when I took my PS5 to my family's house for Christmas vacation. We both have the same SSID because I set up both access points but they changed the password when they forgot it because they're a bunch of bozos.

My PS5 controller refused to connect to my PS5 and I couldn't figure out why. I gave up and after a few days tried again only to realize that the PS5 controller can't connect to the PS5 wirelessly when the wifi was connected but the password was invalid. I still don't know why it was a problem or if it still is a problem but it was a monster to debug. lol

The reason I didn't fix the wifi in the first place was that I didn't have a spare USB C to USB A cable to hardwire my controller and I was playing a singleplayer game. I think it was last of us.

One of the sysadmins at a friendly company had the same problem... only that it was a >2km link in a densely built-up city and it turned out to be a crane that moved in on rails each morning with the beginning of a shift and then moved out in the evening!

Took a guy standing there with binoculars to realize what was going on...

I also had another story: my friends asked me to troubleshoot their DSL connection. It dropped out sometime after the sun set and came back in the morning.

Sure enough, this turned out to be RFI from newly installed solar invertors, creeping down the shield of an unused CB radio coax that ran parallel to the phone wiring.

Grr, I hate DSL...

I feel like this story started off seeming way more mysterious than it actually was because it took so long to get to mentioning the crucial bit (the long distance WiFi bridge).

I read about random bit flips but haven't read a good anecdote about it, if anyone can be so kind.

Nice story! My guess was on either the water cooling an overheated device, or weight of water bending the roof on which the antenna is attached.

This should have been a microwave link from the start.

Good read, but i was convinced as soon as i read the title that the rain was shielding the house from a near by transmitters that was blasting too much power.

TL;DR: A tree grew into the signal path. Rain weighed it down, bending it out of the way.

Rain can improve signal quality by lowering the noise floor. Essentially, it drowns out the weaker signals originating from other emitters, making your own signal stand out.

As soon as they mentioned the directional wifi i knew it was something physically between the antennas but was guessing human behavior. The tree was a surprise.

Back in the dialup days, my dialup would die, and be unable to re-connect at dusk. Other than that, it was fine, for dialup.

I hate how fake this sounds since it's a funny story.

Trees leaves being weighed down by a slight drizzle? What tree does that? None around where I live.

A tree blocking signals that strong as well? Doesn't make sense to me either.

To add another weird tech issue to this collection: The camera shy Raspberry Pi. A model of the RPi would reboot when photographed with a flash: https://www.bbc.com/news/technology-31294745 (2015)

Happy April 1st! This post is part of April Cools Club: an April 1st effort to publish genuine essays on unexpected topics.

Honestly, reading "April 1st!", I was expecting this to be one of April's fools but it turned out to be a true and amusing story.

The author was lucky to solve a technical problem in a non-technical way, unlike me!

A decade ago, I had a weird Internet connection issue. The upload speed suddenly dropped to near zero kb/s while the download was alright. I contacted my ISP, and for weeks, they were unable to figure out what was going wrong. I reached out to my neighbor and offered him to pay his Internet bill in exchange for sharing his Wi-Fi with me until my ISP solves my problem, and he kindly agreed. After about three months, my ISP's technical staff was still unable to fix the issue. I gave up, and guess what I did to get around this?! I just moved away to another distant home.

Could also have be that the neighbor have a not compliant WiFi device that send out deauthentication packages, then it would also work better during rain.

And the same upgrade would often fix it

"Close the window you're letting all the WiFi out"

I thought it would be because waves travel longer distances on water.

The title might've been a Fleetwood (the other kind of) Mac reference.

    o/~ Wi-Fi's only working when it's rainin'
        Players only stutter when they're buff'rin'
        Websites, they will page load oh so slooooww
        When the rain falls down, you can download

This is how you know the WiFi is Garbage - only happy when it rains.

At least you get a clue in this case (and the famous 500 miles email), I was having sporadic disconnections with cable internet for the last 2 month and my ISP can’t find anything wrong.

Had to switch back to DSL and pay more for slower speed.

At Pinterest, when we were working from one of the founder's apartment, the internet went down. Lots of debugging later and we traced it to a cable that a squirrel had chewed threw..

Issue: rain caused tree branch to go lower unobscured wifi

I enjoyed the story, but the writing I enjoyed even more. I really liked the tone and wittiness.

Sounds like it would be a neat excuse to get the children to go out when it's sunny!

I got this far:

"The office and our apartment were a few blocks away from each other..."

and figured it had to be a line of sight transmission.

I encountered this in summer of 1993 when the company I worked at installed infrared (I think) transmission across our two offices, separated by 250m. When the summer sun swept behind the transmitter in the northwest-ish, the wifi went out for about an hour each evening.

I will be adding this one to https://500mile.email ! What a great story.

I remember hearing about a few common failure modes for early internetworking of adjacent buildings. The first being running a bare twisted pair cable between buildings. Worked fine until the next lightning storm, and then a nearby strike fries the equipment on both ends. You have to use grounded conduit to run strands between buildings my dudes.

But the other one was setting up WiFi between buildings, and tended to be more of a problem in academia because the yearly cycles make it a bit more likely. If you set it up in the fall, and everything works all winter until spring comes, when the water in the deciduous tree leaves attenuates the signal. The nasty part of this one is not the failure mode but the timing. Everyone has been happily using and depending on their sweet sweet bandwidth for six months and poof, it’s just gone one fine April morning.

This reminds me of when I used to work for an ISP. Every November the "my internet doesn't work when we turn on the Christmas tree" calls would start. It was usually interference from cheap tree lights, but occasionally it was people unplugging the router to plug in their Christmas tree :D

"Thunder only happens when it's raining"

https://youtu.be/Y3ywicffOj4

1:15

I've had a similar weather experience where my internet connection dropped when it was cold. Turns out some water had seeped into the optical fiber connector, when it froze it broke the connection, and it would recover when it thawed. This one was a nightmare to troubleshoot.

Weighing down the leaves is one possibility, but is it also possible that water adhering to surfaces was creating reflections and providing alternative paths for the signal? I don't know if such a thing could happen at that frequency, but if you imagine looking out a window at night towards a window in a distant building, with a tree blocking the direct line of sight, and someone in the window sending you a message with a flashlight, you would only see the light via reflections. On a dry night the reflections might be matte and hard to see, but on a rain-soaked night you might be able to see stronger and sharper reflections on metal poles, walls, or puddles that were visible from both windows.

I was fully expecting the answer to be that the rain was tamping down some unknown source of wifi interference... Which is a reasonable hypothesis if the packet loss is also within the home network.

I was not expecting the home Internet all went over a long range WiFi bridge, but knowing that a tree makes far more sense as the problem. Strange how it correlates with rain that way.

As soon as it mentioned the line of site antennas I knew it had to be a tree. It often surprises me how much branches can sag from the weight of rainwater

Actually experience the same thing but for different reasons.

I've lived in the same place for 25 years, so I've seen the invention of wifi and then checking every few months for other users on wifi analyzer, I've seen it grown and grown.

Well in that 25 years they've built so many surrounding apartment complexes that the 2.4ghz saturation is absolutely insane. I cannot believe how many networks show up on the analyzer in 2024, has to be well over 100.

But when it rains, it cuts off dozens of those other apartments, and I get better signal inside my own apartment.

Another fun story is the "My Car does not start when I buy Vanilla ice cream": https://news.ycombinator.com/item?id=21779857

Reminds me of a song by Fleetwood Mac. Wifi only woooorks when it's raaaaining ...

We had an office in a very old building downtown with no access to fibre. The best internet we could get at the time was a 3G router in the window. Every afternoon at the same time our connection would drop down below 1 Meg and become unusable. Eventually we realised that down the street there was a large school and every afternoon when classes were over, hundreds of young people would turn in their phones and saturate our cell.

Here I thought it would be because it would be interfering with noise from other networks.

Offtopic.

Not sure how you're styling your links, but in a dark mode view, they are effectively illegible.

https://imgur.com/a/aSbpVF8

The WiFi only works when it's raining (ps. one critical part of my WiFi setup is outdoors and depends on having a clear line of sight)

Reminds me of that time when my desktop computer wouldn't turn on if the printer's USB was plugged in to the wrong kind of port. Took me some time to figure that one out.

Or that other time, when my mom's phone started crashing all of a sudden. Until we discovered, that it was caused by her new ID card in the folding phone case touching the back of the phone.

>> Maybe an antenna connector has corroded from spending years outdoors? Nope.

Most people living in large metros will never fathom how wifi will simply stop working in the suburbs. It is easy to forget that Internet cables -normally hidden in cities- are completely exposed to elements in suburbs

Lost wifi while at parent's ? Check the roof!

I remember when I had ADSL2, I would get increased packet loss when it rained. After I failed to find the culprit, technicians from ISPs tried to debug it to no avail. It turned away when the connection got upgraded from ADSL2 to VDSL2.

That would be ironic on your wedding day.

The author’s completely over the top reaction to the plausible and not especially weird titular statement gets old, quick.

Especially when they reveal that the network is using wifi antennas over a non-insignificant distance in an urban setting. Of course it’s the local wireless point to point bridge! The first thing you’d do is look down the line of sight for interference.

bit disappointed ... this is a very obscure set up and frankly speaking under those circumstances sth like "rain affects the wifi [either way]" is obviously not even close to magical thinking. definitely not worth almost 1000 upvotes.