Send an DMR message to w with zip like so (a w 14207) and receive back a weather forecast for your location. You can specify “where” “when” and “what”. The “where” can take the following form:
- Any US callsign
- Any callsign[-ssid] or object known to api.aprs.fi that has a location including AIS ships.
- City,ST (NOTE: City,ST must be the first part of the message. City and state must be separated by a comma. Spelling is based on the us.zip file at geonames.org. US postal service abbreviations for states.)
- 5 digit zipcode
- CWOP station id (I.E. DW6273)
- 4 or 6 character Maidenhead Grid. (cn81, or cn81uh)
- lat/lon Using decimal degrees I.E. 41.123/-122.1123
- 4 character ICAO station (KJFK KSFO etc…) returns METAR report.
- 3 character IATA station (SFO, LAX etc) returns METAR report.
If the resulting location is outside the coverage of the United States National Weather Service, an error message is returned. When an ICAO station is given, the default “what” is changed to METAR. (You can specify full, or brief along with the ICAO station to get a normal forecast instead of the METAR report.)
The “When” can be a day of the week, with an optional “night” to indicate the evening forecast. Abbreviations for days of the week are recognized (wed instead of Wednesday)
today — (default)tonighttomorrow [night]Monday [night]Tuesday [night]Wednesday [night]Thursday [night]Friday [night]Saturday [night]Sunday [night]
The “What” can be:
brief — default. Short forecast. Usually a single APRS Message.
full — multi line more complete forecast.
current — Returns current conditions from the nearest NWS station.
metar — Returns the current conditions from the specified. ICAO station in METAR form.
If an ICAO station is not specified, the nearest ICAO station to the given location is used.
cwop — Returns weather report from the CWOP station nearest to the given location.
If no location was given, it assumes your location.
If a callsign was given, it returns results from the CWOP station nearest to the location of the callsign
info — Returns name,address, license class from the FCC ULS for the given US callsign.
help or ? — Return a help message
whois — same as “info”
who-is — same as “info”
The brief forecast usually fits within a single APRS message. The full forecast will be split among multiple APRS messages. If there are any active weather hazards (such as winter weather warnings etc..) in the forecast zone, the hazard will be included with the forecast and may cause the brief forecast to flow into multiple messages. The “current” conditions are taken from the nearest National Weather Service reporting station.
Special “Outernet/OUTNET” flag. For users with Outernet satellite receivers (https://outernet.is/), the reply can be copied to the global Outernet satellite feed by adding the word “outnet” to your query.
Examples
Example forecast request messages sent to W
Any message less than 3 characters
Returns a brief forecast for the current location of the sending station.
Any US callsign
Returns a brief forecast for the city listed in the FCC ULS for the given callsign even if they don’t use APRS.
Boston,MA Saturday full
Returns Saturday’s full forecast near Boston, MA
bozeman,MT cwop
Returns the current conditions as reported by the nearest CWOP station to Bozeman,MT.
Sault Sainte Marie,MI
Returns a brief forecast for Sault Sainte Marie, MI.
Coeur D Alene,ID Tonight full
Returns the full forecast for tonight in Couer d’Alene, Idaho.
Tomorrow 96067
Returns tomorrow’s forecast for Mount Shasta, CA
Tonight
Returns the forecast for tonight at my current location
Tuesday night full
Returns the Tuesday night full forecast for the most recent location of the requesting station.
w1aw
Returns the current forecast for the location of station W1AW
usna-1 Sunday
Returns the forecast for the Army Navy football game on Sunday. (Assuming usna-1 is at the stadium)
CN81uh
Returns the forecast for the center of maidenhead grid CN81uh
41.123/-121.334
Returns the forecast for Lattitude 41.123N, Longitude 121.334W
current
Returns the current conditions as reported by the nearest National Weather Service reporting station.
metar
Returns the conditions at the nearest ICAO weather station in METAR form.
KSFO
Returns the current conditions at San Francisco International Airport in METAR form.
SFO
Returns the current conditions at San Francisco International Airport in METAR form.
KJFK brief
Return a brief weather forecast for JFK International airport. (note: this is NOT a TAF forecast)
w1aw metar
Returns a METAR report from the ICAO weather station nearest to station w1aw.
whois w1aw
Returns name,address,call class from the FCC ULS.
cwop
Returns the current conditions as reported by the nearest CWOP (Citizen’s Weather Observer Program) station.
“CWOP Station ID” (i.e. DW6273)
Returns the current conditions as reported by the specified CWOP station.
‘CALLSIGN’ cwop
Returns the current conditions from the CWOP station nearest to ‘CALLSIGN’.
outnet
Outnet can be added to any query to cause the report to also appear on the Outernet satellite APRS feed.
metar outnet
Returns a metar report for the nearest ICAO station. The report will also appear on the Outernet satellite aprs feed.
International users, note: your query should include a location, or have previously sent at least 1 position report. Otherwise, the system will not know where you are. United States users, if you do not include a location in your query, and have not sent a position report, the system will use your address as listed in the FCC ULS database.
Messages are “Acked” if requested. The program understands and uses “Reply Acks” if the originating station supports them. If the originating station sends an unnumbered message, then the reply will be unnumbered. However, the program DOES NOT attempt to resend un-acknowledged messages. If you didn’t get a forecast, send the request again.
If the requested location is offshore, then the weather service provides a marine forecast which will likely flow onto two or more messages.
If more than one object exists with the same name (AIS ships can have the same name as APRS objects), the first object returned by api.aprs.fi will be used. Currently there is no way to specify exactly which object.