WXSVR-AU Protocol

The databases above provide a way to interpret the NWS statements the WXSVR-AU application creates and disseminates to the Internet.  A set of shapefiles has been created to allow many APRS clients to graphically depict the watches and warnings.  The format of the shapefiles and beacon statements is being developed so that existing NWS client applications can be used with the Australian data.

The format for the statements generated by WXSVR-AU are:

Area Specific:
CWAPID>APRS::NWS_TTTTT:DDHHMMz,ADVISETYPE,zcs{seq#
CWAPID>APRS::NWS_TTTTT:DDHHMMz,ADVISETYPE,compressed zcs{seq#

General/Full Text Messages:
CWAPID>APRS::BOMCWA   :DDHHMMz,WARNTEXT{seq#

Objects:
FWAPID>APRS:;CWA_PID  *DDHHMMzLATLONICONADVISETYPE{seq#
FWAPID>APRS:;CWA_PID  *DDHHMMzLATLONICONADVISETYPE}multiline{seq#

CWA is the Forecast Area (See ZONE database above). 
PID is the product Code (See PRODUCTS database above).
TTTTT is ADVIS, WARN, WATCH, etc.
ttttz is the issue time.
DDHHMMz is the expiration time.
LATLONICON is the latitude, longitude, and symbol for the object (standard object format).
ADVISETYPE is things like FLOOD, FLASHFLOOD, SVRTSM, SEVERE_WEATHER, etc.
WARNTEXT is a plain text bulletin message for the warning.
zcs are comma separated zone codes or area codes (see the databases linked above to find the zone or area code for your area), or statement text.
compressed zcs is a compressed listing of zones or area codes (see example below)
multiline is the enclosing line structure for the object (see http://wxsvr.aprs.net.au/APRS_Multiline_Protocol.html).
{seq# is a simple checksum and sequence number for each message, and can be decoded as follows:

The first three characters are the "issue time" compressed by assigning 0-9 as themselves, A-Z as 10 thru 35, a-x as 36-59, where it is DHM (Day of the Month-Hour in 24 hour format and Minute). Up to 16 this reads as hexadecimal so {A8B** was issued on the 10th at 08:11 Z.

The fourth character is used to identify messages in the event that there are two seperate produts issued at the same time for the same area. In this case the fourth character will be A for the first product, and B for the next and so on.

The final character is used to associate all packets from the same warning. The first four characters for all packets associated with the same warning will be identical, and the last character will be incremented for each packet, so that they can be re-assembled in order by the client if required.

SCTNPW>APRS::NWS-WARN :251500z,WIND,NSZ213, {P7IAA SCTNPW>APRS::BOMSCT :HIGH WIND WARNING THROUGH SATURDAY NIGHT {P7IAB SCTNPW>APRS::BOMSCT :FOR SOUTH COAST {P7IAC

Compressed ZCS

Some warnings cover a large area, and the resulting APRS messages can be very long.

With only a handful of these types of warnings, the D700 memory is full no matter what the message groups setting. WXSVR-AU has a compact format for sending this type of information which looks like: