Quick Start

Send an APRS message to WXCAN with a location. That is all you need.

Want more detail? Add full or extra. Want tomorrow? Add tm. Everything combines freely: ottawa tm full gives a detailed forecast for tomorrow in Ottawa.

Weather Requests

The general format is:

All three parts are optional and can appear in any order. If you omit everything, you get current brief weather at your APRS position.

Location Formats

WXCAN understands many location types:

Time Periods and Shortcuts

Add a time keyword to get a forecast instead of current conditions. Shortcuts save keystrokes on APRS.

Detail Levels

Three tiers. Each builds on the previous one. More detail means more APRS messages (responses are split to fit the 68-character limit).

• brief Default. Quick weather. Usually 1 message.
• full All weather measurements. 2 to 3 messages.
• extra Full weather plus environmental and planning data. 3 to 4 messages.

The tiers are incremental: full contains everything in brief, and extra contains everything in full.

brief What brief Returns

full What full Adds

Everything in brief, plus:

extra What extra Adds

Everything in full, plus non-weather environmental and planning data:

Kp, AQHI, and sunrise/sunset only appear for current conditions requests, not for forecasts of future days.

Forecast Responses

When you request a forecast (tomorrow, tonight, a weekday), the same detail tiers apply. The data comes from the forecast period instead of current observations.

Forecast extra adds UV, frostbite warning, and wind forecast text for that period. Kp, AQHI, and sunrise/sunset are not included in forecasts since they are current-moment data.

7-Day Compressed View

The 7d command gives up to 7 daytime forecast periods compressed into one APRS-friendly line. Night periods are excluded.

Each entry reads as: Day+/-Temp:Condition

• Day = 3-letter abbreviation of the period name
• Temp = high temperature with +/- sign (+4 means 4 degrees C, -2 means minus 2)
• Condition = compressed weather condition code

Day Abbreviations

7-Day Condition Codes

These short codes represent the forecasted weather condition for each day in the 7-day view:

METAR (Aviation Weather)

Get raw METAR observation data for any ICAO airport worldwide.

Use any valid 4-letter ICAO code. Works for international airports too (metar KJFK). Data comes from NOAA/NWS.

Drone / UAV Forecast

Purpose-built weather report for drone and UAV operators.

drone and uav are interchangeable. The report includes:

• Temperature, wind speed/direction, gust, visibility, dew point, POP
• Kp geomagnetic index (current + 0-3h + 3-6h forecast)
• NRCan geomagnetic zone code (VIC, OTT, MEA, FCC, PBQ, BLC, RES)
• All ICAO airports within 30 km with distance in km
• Current condition

Airport Search (Radius)

Find all ICAO airports within a given radius.

drone srch works the same way. Alternate syntax: uav montreal srch 50 (location before srch) is also accepted. Only CY* and CZ* airports (Transport Canada certified or registered) are listed.

Airport Info

Look up GPS coordinates, Maidenhead grid square, and tower radio frequency for any Canadian CY/CZ airport.

Frequencies come from OurAirports with corrections from the Nav Canada Canada Flight Supplement (CFS). Multiple tower frequencies are separated by a slash.

Weather Alert Subscription

Subscribe to receive automatic push notifications when Environment Canada issues weather alerts near your location. The location you provide when subscribing determines which EC alert region you are matched to. You will only receive alerts relevant to that area, not the entire province.

WXCAN pushes yellow, orange, and red level alerts only:

• Yellow: watches and advisories
• Yellow/Orange/Red: warnings (severity indicated by color in EC title)

Special weather statements (grey level) are not pushed.

How Alert Push Works

WXCAN checks all Environment Canada regional alert feeds for your province every 30 minutes. When a new alert is found near your subscribed location, you receive a compressed message:

What gets pushed and what does not:

Important details:

• Proximity-based. Alerts are matched to your nearest Environment Canada city. You only receive alerts whose EC region matches your location. You will not receive alerts for distant parts of your province.
• Fire and forget. Each alert is pushed once only. If your radio is off, you will not receive it and it will not be re-sent.
• No duplicates. If the same warning is still active on the next check, it is not re-sent.
• 30-minute cycle. There can be up to a 30-minute delay between EC issuing an alert and you receiving it.

60-Day Inactivity Expiry

Subscriptions automatically expire after 60 days of inactivity. Any message you send to WXCAN resets the 60-day clock. It does not have to be a subscription command. A weather request, a help request, a METAR query, anything counts as activity.

If your subscription expires:

• WXCAN sends you a one-time notice: WX alerts unsubscribed (inactive 60d). Send wxsub to re-enable.
• You stop receiving alert pushes
• You can re-subscribe at any time by sending wxsub again

On-Demand Alert Check

Check for active weather alerts near any location without subscribing. Only yellow, orange, and red level alerts are returned. Special weather statements are excluded.

Accepts city name, grid square, or no location (uses your APRS position). The bot resolves your location to the nearest EC city and shows only alerts whose region matches that city.

Inline Warnings

When you request weather for a location that has an active yellow, orange, or red alert in the EC city XML data, it is automatically prepended to the response. You do not need to request it separately.

The prefix indicates severity: WX!YLW: (yellow), WX!ORG: (orange), or WX!RED: (red). This is separate from the subscription push system and appears regardless of whether you are subscribed.

Message Splitting

APRS messages are limited to 68 characters. When a response exceeds this, WXCAN splits it into numbered parts:

Each part is sent with a message ID requesting an ACK. The bot waits up to 5 seconds for your acknowledgment before sending the next part. There is a 2-second pause between parts. If no ACK is received after 2 attempts, the bot moves on. You may still receive the message even without ACK.

No Location? No Problem

If you omit a location, WXCAN looks up your last known position on aprs.fi. This works if you have transmitted a position beacon recently.

If no position is found on aprs.fi, you will receive: No location provided & no APRS position found.

Why "Cond: Unknown"?

Some smaller Environment Canada stations do not report a text condition (Cloudy, Clear, Sunny, etc.) in their current observations. All numeric data (temperature, wind, pressure, humidity) is still available and accurate. This is an EC data gap at certain stations, not a bot error.

Data Sources

Help Command

Send help or ? to WXCAN to receive a compressed command reference via APRS. The help text is split across multiple messages.