About Tropical Cyclone Advisory

Example of text advisory

Tropical Cyclone Advisory (TCA) is provided from Tropical Cyclone Advisory Center (TCAC) designated by ICAO as advisory information for MWOs (meteorological watch offices) which issues SIGMET for tropical cyclones.
TCAC Tokyo issues TCAs when a tropical cyclone of Tropical Storm (TS)* intensity or higher, or a tropical depression which is expected to become TS intensithy wihtin 24 hours exists in the area of responsibility of the Center.

TCA contains the following data;
Time of origin (UTC), name of TCAC, name of tropical cyclone, advisory number
Analysis information: observed position of the centre (lat/lon in degrees and minutes), location of CB cloud (lat/lon in degrees and minutes) and vertical extent (flight level), direction and speed of movement (KT), changes in intensity, central pressure (hPa), maximum surface wind (KT)
Forecast information (+6, 12, 18, 24 hours): forecast time (UTC), centre position, maximum surface wind.

* Tropical Storm: A tropical cyclone with its maximum surface wind speed (10-minite average) near the center is in the range of 34 knots to 47 knots.

Example of graphical advisory

TCA in graphical format (TCG) contains gale force wind area in addition to the information included in text format TCA.
In TCG, CBs which meet the following conditions are determined as CB associating a tropical cyclone:

a) CBs existing within a gale force wind area;
b) CBs existing out of a gale force wind area, but connect to CB grids within a gale force wind area; and
c) CBs covering a wide area (about 100 km x 100km scale).

When TCA is issued for a tropical cyclone which is expected to reach Tropical Strom intensity within 24 hours, gale force wind area is not depicted. In this case, CBs existing near the center (within a 160km radius) of the tropical cyclone will be depicted.

Example of IWXXM Format Advisory

Please click the following link to download an example of IWXXM Format Advisory
Example of IWXXM Format Advisory

The details about IWXXM Format are explained in the following documentation:
GUIDELINES FOR THE IMPLEMENTATION OF OPMET DATA EXCHANGE USING IWXXM THIRD EDITION (MAY 2019), ICAO.