An APRS weather station is an amateur radio station that, instead of only beaconing where it is, beacons what the weather is doing where it sits — wind, temperature, rainfall, humidity, and barometric pressure — into the worldwide APRS network. Mixed in among the cars, balloons, boats, and digipeaters on a live APRS map is a quiet, dense layer of surface weather: hundreds of thousands of amateur and automated stations reporting local conditions every few minutes, all in the clear, all viewable from a browser.
This guide explains what an APRS weather station actually is, how the WX symbol and its data fields work, how a reading travels from a backyard anemometer to a marker on a live map, how to read that marker once it is in front of you, and why this layer matters for SKYWARN and storm spotting. If you are new to the protocol itself, start with What is APRS? and come back; everything below assumes you know roughly what a packet and an iGate are.
At its simplest, an APRS weather station is a normal APRS station with a weather instrument attached. A licensed operator connects a weather console — a Davis Vantage, an Acurite, a Fine Offset clone, or any instrument that exposes its readings — to software or to a weather-capable terminal node controller (TNC). That software reads the live sensor values, packs them into the APRS weather format, and pushes the resulting packet either onto the local APRS frequency via a radio, or directly into APRS-IS over the internet.
The important distinction from a plain position beacon is the payload. A car running APRS sends a latitude, longitude, course, speed, and a symbol. A weather station sends a position too — it is, after all, a fixed point on the earth — but its data field is given over to meteorology rather than motion. The protocol reserves a specific, compact text layout for this, so any APRS client, including the aprs.world live map, knows exactly where to find the wind speed, the temperature, and the rest.
Weather stations are typically fixed and beacon on a slow cadence — every five to ten minutes is common — because surface weather does not change second to second and there is no value in flooding the channel. That slow, steady rhythm is part of what makes the weather layer so well behaved on a map.
On the map, a weather station almost always wears the canonical WX symbol: a blue circle with a white letter W. That symbol is the network's shorthand for "this marker carries weather data, click it." When you scan a region on a live map and want to find the weather layer specifically, the blue-W markers are what you are hunting for. You can see how it sits among the rest of the catalogue on the APRS symbol chart, and the broader logic of how symbols are encoded is covered in APRS Symbols Explained.
WX is simply the amateur radio abbreviation for "weather" — it predates APRS by decades. When operators talk about a wx station or wx aprs, they mean exactly the weather-reporting stations described here.
The APRS weather format is a fixed-position text string appended to the position report, and each field has a defined meaning. A full weather packet can carry:
Two points trip people up. First, the on-air units are fixed by APRS's early standardisation; a good viewer converts them to whatever units you prefer, so do not read too much into the raw encoding. Second, not all fields are mandatory — a station only sends what its hardware measures. A bare-bones temperature-and-pressure station is a perfectly valid weather station; a full Davis rig with anemometer, rain gauge, and hygrometer fills in every field. When a value is missing, the protocol uses a placeholder, and a sensible map omits that row rather than showing a zero that would be misread as "no wind" or "0 °C".
The path a weather reading takes is the same backbone every APRS datum rides, just with a meteorological payload. There are two common entry points.
Over RF, then via an iGate. A licensed station keys its radio and transmits the weather packet on the local APRS frequency (144.800 MHz across much of IARU Region 1, 144.390 MHz in Region 2, varied in Region 3). A nearby iGate hears it, decodes it, and uploads it to APRS-IS. This is the classic on-air weather station.
Directly into APRS-IS. Many weather stations have no transmitter at all and instead feed their readings straight into the APRS-IS internet network as an internet weather station. This is common where the operator wants their data on the map but has no need to occupy the RF channel, or where local RF coverage is poor.
From APRS-IS onward the flow is identical to any other APRS data, and it mirrors what the APRS web tracker guide describes for positions:
api.aprs.world — holds a persistent connection to APRS-IS and parses every packet it sees.End-to-end, a fresh reading appears on the map within seconds of the packet hitting APRS-IS. The slow part is never the network — it is the station's own five-to-ten-minute beacon interval. If a weather marker has not updated in eight minutes, almost always the station simply has not transmitted yet, not that the map is stale.
To look at APRS weather, you do not need a licence, an account, or any hardware — only a browser. Open the live map at aprs.world (or aprs.fi, the long-standing reference visualizer; both consume the same APRS-IS feed), and the weather layer is already there among the markers. A few practical habits make it easier:
Because APRS is entirely in the clear, every one of these readings is public by design. There is nothing private to unlock — the whole network is a public bulletin board, weather included.
Putting your own weather station on APRS is a matter of three pieces: an instrument that measures the weather, something that formats the readings into an APRS weather packet, and a path onto the network. The specific products in each slot change over the years, so treat the following as categories rather than a shopping list, and check current documentation before buying.
A licence is required only for the RF path, because that involves transmitting on amateur bands. The internet-only path still follows APRS-IS access conventions but does not put you on the air. Beyond that, the right choice depends on your goals: RF weather stations strengthen the local on-air network and help fill coverage, while internet feeds are simpler to stand up and just as visible on the map.
A subtle but genuinely useful distinction is between a WX-capable station and a weather object.
A WX-capable station is a real station with its own callsign and its own sensors. The weather you see belongs to that station, at that station's location, reported by that station. It is autonomous.
A weather object, by contrast, is an item that one station injects into the network on behalf of a location that has no transmitter of its own. APRS objects are named, position-bearing entities created and maintained by a host station — think of a station relaying a government or airport weather feed, or marking conditions at a remote point. The object shows weather at a place, but it is owned by another callsign; if that host station stops transmitting the object, it ages off the map. Objects can also be effectively positionless in origin — created by a station that simply asserts a location for the item.
For a map reader the practical takeaway is this: when you click a weather marker, the callsign you see may be the station that owns the data rather than a physical box at that exact spot. That is not an error; it is the difference between an independent weather station and a relayed weather object. Both are legitimate, and both belong on the map.
The reason this layer matters beyond hobbyist curiosity is density. Across a populated region, APRS weather stations form an informal mesonet — a fine-grained mesh of surface observations updating every few minutes, far denser than the official station network in many areas. For SKYWARN spotters, storm chasers, and EmComm volunteers, that mesh is a live situational-awareness tool.
When severe weather approaches, the patterns that matter are visible across neighbouring stations on a live map: barometric pressure dropping sharply, wind direction veering, gusts spiking, rainfall counters climbing fast. Watching a row of stations along a frontal boundary report those changes in sequence gives a spotter a sense of where a cell is and how fast it is moving — useful context to fold into a report alongside what they see out the window.
Two honest caveats keep this in proportion. First, APRS weather supplements, never replaces official radar, watches, and warnings; it is amateur instrumentation of varying calibration, not a certified observation network. Second, coverage is uneven — dense in some regions, sparse in others — so the picture is only as good as the local station population. Used with that understanding, though, a live APRS weather map is a genuinely valuable layer for anyone watching the sky.
An APRS weather station is an amateur radio station that beacons live meteorological readings — wind, temperature, rain, humidity, and barometric pressure — over the APRS network instead of, or alongside, a plain position. The data comes from a connected weather instrument such as a Davis or Acurite console, gets formatted into an APRS weather packet, and is transmitted on the local APRS frequency or fed straight to APRS-IS. Once on the network it appears on any public APRS map.
WX is the long-standing amateur radio abbreviation for weather, and in APRS it identifies a packet that carries meteorological data. A WX-capable station usually shows the blue-circle-with-white-W weather symbol on the map, and its packet encodes wind direction and speed, gust, temperature, rainfall, humidity, and barometric pressure in a fixed text format. Not every field is mandatory; a station sends whatever sensors it has.
Open a public APRS visualizer such as aprs.world or aprs.fi in any browser — no licence or login is needed to look. Weather stations appear under the WX symbol, and clicking one shows its latest wind, temperature, rain, humidity, and pressure readings. You can search a specific callsign on the station page to see that station's recent weather history.
A full APRS weather packet reports wind direction in degrees, sustained wind speed, peak gust, air temperature, rainfall over the last hour and last 24 hours plus rainfall since local midnight, relative humidity, and barometric pressure. Stations report only the parameters their hardware measures, so a simple station might send just temperature and pressure while a full Davis Vantage rig sends everything. Values are timestamped by the network when they arrive.
You need a weather instrument that exposes its readings, a way to format those readings into an APRS weather packet, and a path onto the network. A common combination is a Davis or similar weather console feeding software or a weather-capable TNC, which then either keys a radio on the APRS frequency or uploads directly to APRS-IS as an internet weather station. Specific models change over time, so check current amateur weather software documentation for supported instruments.
A WX-capable station beacons weather data tied to its own callsign and position, so it is a real on-air station with sensors. A weather object is a positionless or position-bearing item that one station injects on behalf of a location that has no transmitter of its own — for example relaying a government weather feed. On the map the object shows weather at a point but is owned and maintained by another callsign, not by an independent station at that spot.
Yes. A dense field of APRS weather stations gives SKYWARN spotters and storm chasers a live mesonet of surface wind, pressure, and rainfall that updates every few minutes across a region. Watching pressure fall sharply or gusts spike at neighbouring stations on a live map helps build situational awareness, though APRS weather supplements rather than replaces official radar and warnings.
No. Viewing the live weather feed on a public APRS map requires no amateur radio licence and no account. You only need a licence if you want to transmit your own weather station's readings on the amateur APRS frequency. Internet-only weather feeds into APRS-IS still follow APRS-IS access rules, but simply watching the map is open to anyone.