Somewhere along the way, checking the sky turned into a subscription. Fat Tail is the correction: live readings from calibrated airport sensors near you, the same data pilots trust before takeoff, decoded for everyone and free for good.
The data has been sitting there this whole time, public and free, while apps charged you for a prettier version of it. Type a US ZIP code and take it. Live field report, nearest airport sensor, no signup, no trial, nothing to close. Like it? The app does this automatically, everywhere you go.
Every reading in Fat Tail comes from a real instrument at a real airport, professionally maintained, continuously calibrated, updated the moment conditions change. You see which station it came from, how far away it is, and how fresh the observation is. Pull down to refresh and a green sweep wipes the screen, new readings, straight from the field. When it's raining, Fat Tail says so, because a sensor six miles away is getting wet. No interstitial ad plays first.
Temperature, feels-like, wind, gusts, humidity, visibility, pressure, and cloud layers, big, bold, and straight from the source. Conditions rated with aviation color codes: green when it's clear, red when it's rough.
Animated NOAA radar centered on you, a full hour of measured frames, five minutes apart, with a tappable timeline. Real returns from real radar sites, nothing synthesized.
Enable the compass and the wind arrow tracks as you turn, always pointing the true direction the wind is moving, like holding a hand compass.
Hourly and 7-day forecasts from the National Blend of Models, the multi-model blend NWS forecasters themselves start from. Tap any hour or day to expand the full detail.
Every reading shows where it's headed, temperature, wind, and pressure trends measured over the last three hours. When pressure falls fast, Fat Tail tells you the weather is likely turning, before the radar shows a thing.
When conditions change fast enough, stations transmit special unscheduled reports. Fat Tail flags them the moment they appear, a built-in "something is happening right now" signal no model-based app has.
No accounts. No analytics. No servers watching you. Your location is used on-device to find nearby stations and never stored, shared, or sold. Free apps usually mean you're the product. This one just means it's free.
GPS finds your nearest station automatically, or type any US ZIP and get its field report. Save up to ten places (home, the cabin, mom's house, the job site) as one-tap chips. Checking on somewhere you love takes two seconds.
Every screen ends with the raw station transmission, and every chunk of it is tappable. Tap "BKN035" and learn it means broken clouds at 3,500 feet. By week two, you'll read METARs like a pilot.
Dark like a cockpit display, loud where it counts. Every screen ends with the raw station transmission.
Fat Tail is free forever, and it's just getting started. Here's what just landed, and what's next.
City search, offline: 31,870 US cities and towns, bundled inside the app. Type a name, get the nearest airport sensor. The whole index is 0.78 MB and searches entirely on your phone, so no server ever sees a keystroke. That's not a privacy setting, it's the architecture. Everything from 1.0.4 still stands: widgets, UV index, air quality, the refined Daily Brief. Still free. Still no accounts, no tracking, no ads.
Search any of 31,870 US cities and towns and get the airport sensor nearest it. The entire index ships inside the app at 0.78 MB, smaller than one photo, and every search runs on your phone. Your keystrokes have nowhere to go because nothing gets sent.
Home screen widgets with the essentials: measured temperature, conditions, and the station it came from, colored by the aviation category, green when it's clear, red when it's rough. The widget fetches its own reading, so the truth is on your home screen before you even open the app. Small and medium sizes, more coming.
The Daily Brief now carries the UV index, this hour and the day's peak, straight from the EPA, plus the air quality index from the AirNow monitor nearest you. Both measured by government instruments, both labeled with their source, both free. Sunscreen decisions and "should I run outside today" answered in one glance.
Open the app and get the day in three honest sentences, "Dry until 3 PM, then storms. Tonight clears, low 77°." Behind it, a full page: active warnings, an hourly temperature graph, golden hours for light-chasers, dry windows for dog walks, and the best hour to be outside, all built from station measurements plus the NWS forecast, with the receipts shown.
Every day, Fat Tail saves what the forecast promised and checks it against what the station actually measured. The Receipt shows yesterday's verdict; the ledger keeps the running score. Deeper grading, hour by hour and model by model, is still coming as Prove It Mode.
When a storm threatens, Fat Tail becomes a hurricane instrument: the official NHC forecast cone alongside live measured wind and pressure from stations in the path. Watch the barometer fall in real numbers as it approaches, not a model's guess, the actual atmosphere. And free, like everything else here, because the week a storm is pointed at your house is the single worst week to hit somebody with a paywall.
When weather is moving through, a Live Activity tracks it right on the lock screen, the station's latest readings, the radar picture in miniature, and when it clears. Glance at your phone, know the storm. No unlocking, no opening, no hunting.
Weather apps forget everything the moment it happens. The Station Log keeps your station's history, yesterday's pressure crash as a graph, the hottest August 14th on record, and when the big one passes: your station's storm archive, measured minute by minute.
The radar network already tracks every organized storm cell, with its direction and speed. Rain Watch reads that tracking and tells you plainly: "Rain on the radar about 20 minutes out, moving in from the southwest." A radar estimate, labeled as one, never fake minute-by-minute precision.
Live more than 25 miles from your station? Fat Tail will show the nearest few stations side by side, plus the NWS estimate for your exact spot, labeled as the estimate it is. Measured and modeled, next to each other, so you can see the spread. No other app will show you that comparison, because it grades their homework too.
Twenty-seven plain-English guides: what every number means, how the instruments and radar work, how forecasts are made and where they fail, and what actually keeps you safe when the weather turns. Somebody would absolutely sell you this as a course. Here it is instead. No signup, no email capture, no paywall, not ever.
Right now. Fat Tail is live on the App Store for iOS, free. Android is on the roadmap because free weather should reach everyone. Download it here.
Yes, as of 1.0.4. Home screen widgets in small and medium sizes show the measured temperature, conditions, and your station, colored by the aviation flight category, green when it's clear, red when it's rough. The widget fetches its own reading, so it stays current even when the app hasn't been opened. Long-press your home screen, tap the plus, and search Fat Tail.
There isn't one, and honestly the question says a lot about where we've ended up. NOAA and the National Weather Service collect this data with public money. You already paid for it once. Charging you a second time to look at your own sky is a business model, not a service. Fat Tail delivers it well and gets out of the way: no accounts, no tracking, no paywalled features, no "upgrade to see the radar." Weather should be free. Walk outside, or check Fat Tail.
A METAR is the standardized weather report that airports transmit, temperature, wind, visibility, pressure, and cloud layers, measured by calibrated sensors and updated at least hourly (and immediately when conditions change fast). It's the data pilots check before every flight. Fat Tail decodes it into plain English, and lets you tap any part of the raw code to learn what it means. Full guide to reading a METAR →
Most weather apps show a model's estimate interpolated for your location. Fat Tail shows measurements from a physical instrument at a nearby airport. You see which station it came from, how far away it is, and how fresh the reading is. When it's raining, Fat Tail says so, because a sensor a few miles away is getting wet.
Airport instruments are professionally installed, continuously calibrated, and maintained to aviation standards, lives depend on them being right. Backyard stations are fun but wildly inconsistent (a thermometer above a driveway reads hot). Fat Tail always shows the distance to your station, so you know exactly where the truth is coming from. Why airport sensors →
It's confidence times coverage, roughly, the odds that measurable rain falls at any given point in the area during the period. In a Florida summer it usually means scattered storms will pop somewhere; your spot has about a 40% shot of being under one. Fat Tail shows the forecast probability and the measured reality side by side, and when the station reports rain, the measurement wins the screen. More on rain probability →
Stations normally report hourly, but when conditions change fast enough (a storm hits, visibility drops, wind shifts hard), they transmit an unscheduled special report. Fat Tail flags these the moment they appear. It's a built-in "something is happening right now" signal that model-based apps simply don't have. Watches vs. warnings →
Falling pressure means the atmosphere over your station is changing, often the first measurable hint of weather organizing, before radar shows a thing. Fat Tail tracks each station's three-hour pressure trend and warns you when it's falling fast. The number matters less than the direction. How to read a pressure trend →
No. No accounts, no analytics, no servers of ours watching you. Your location is used on your device to find nearby stations and is never stored, shared, or sold. The App Store privacy label reads "Data Not Collected", because there's nothing to collect.
Observations come from NOAA's Aviation Weather Center (the METAR network). Forecasts come from the National Weather Service's National Blend of Models, the multi-model blend NWS forecasters themselves start from. Radar imagery is NOAA NEXRAD served via Iowa State Mesonet. All public, all taxpayer-funded, all straight from the source.
METAR stations exist worldwide, so observations work in most countries. Forecasts and radar currently use US sources (NWS and NEXRAD), so international coverage is observations-first for now.
It's a statistics term: a fat-tailed distribution is one where extreme events happen more often than averages predict. That's weather, most days are ordinary, but the days that matter are the outliers. Fat Tail is built for those days: real measurements, because when the rare stuff happens, you don't want a smoothed-out guess.