SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Geraldton Perth Date: 4 November, 2025 T-index: 110 Bearings: 162 341 Distance: 373 km First Mode |--------F r e q u e n c y (MHz)---------| Second Mode 1F 53-64 1E 24 1 5 10 15 20 25 30 35 40 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 7.2 5.2 3.3 BBFF%.. 00 01 7.6 5.8 3.6 ABFF%%. . 01 02 8.1 6.1 3.8 ABBFF%. . 02 03 8.5 6.3 3.9 ABBFF%% .. 03 04 8.8 6.4 3.9 ABBFF%% .. 04 05 9.0 6.4 3.9 ABBFF%% ... 05 06 8.7 6.3 3.9 ABBFF%% .. 06 07 8.5 6.0 3.7 ABBFF%% .. 07 08 8.2 5.6 3.5 ABFFF%% . 08 09 8.1 5.0 3.2 BBFFF%. . 09 10 7.9 4.0 2.7 ABFFF%%. . 10 11 7.5 0.8 0.0 FFFFFFF%%. 11 12 7.1 0.8 0.0 FFFFFFF%.. 12 13 6.5 0.8 0.0 FFFFFF%%. 13 14 6.1 0.8 0.0 FFFFFF%.. 14 15 5.9 0.8 0.0 FFFFF%%.. 15 16 5.7 0.8 0.0 FFFFF%%. 16 17 5.5 0.8 0.0 FFFFF%.. 17 18 5.1 0.8 0.0 FFFFF%. 18 19 4.7 0.8 0.0 FFFF%%. 19 20 4.5 0.8 0.0 FFFF%.. 20 21 4.7 0.8 0.0 FFFF%.. 21 22 5.5 2.8 2.0 AFFF%.. 22 23 6.6 4.4 2.9 ABFF%%. 23 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT =============================================================================== |. USABLE LESS THAN 50% OF DAYS |% USABLE 50% TO 90% OF DAYS | |B BOTH E and F MODES 90% OF DAYS |M MIXED FIRST AND SECOND F MODES | |F FIRST F MODE ONLY |E E-LAYER PROPAGATION |P 90% E and 50-90% F | |S SECOND MODES ONLY |A HIGH ABSORPTION |X COMPLEX MODES | (c) 4-Nov-2025 BoM Space Weather Services, Sydney Australia +61-2-9213-8000