SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Geraldton Perth Date: 18 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 53-65 1E 24 1 5 10 15 20 25 30 35 40 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 6.7 5.3 3.4 BBF%%.. 00 01 7.1 5.8 3.6 ABFF%.. . 01 02 7.6 6.1 3.8 ABBF%%. . 02 03 8.0 6.4 3.9 ABBF%%% .. 03 04 8.2 6.4 4.0 ABBFF%% .. 04 05 8.5 6.4 4.0 ABBFF%% .. 05 06 8.2 6.3 3.9 ABBFF%% .. 06 07 7.9 6.0 3.8 ABBF%%% .. 07 08 7.7 5.6 3.5 ABFF%%. . 08 09 7.6 5.1 3.2 BBFF%%. . 09 10 7.5 4.2 2.8 ABFFF%%. . 10 11 7.4 2.0 1.5 AFFFFF%%. 11 12 7.0 0.8 0.0 FFFFFF%%.. 12 13 6.5 0.8 0.0 FFFFFF%%. 13 14 6.2 0.8 0.0 FFFFFF%.. 14 15 6.0 0.8 0.0 FFFFF%%.. 15 16 5.9 0.8 0.0 FFFFF%%. 16 17 5.6 0.8 0.0 FFFFF%%. 17 18 5.2 0.8 0.0 FFFFF%. 18 19 4.8 0.8 0.0 FFFF%%. 19 20 4.6 0.8 0.0 FFFF%.. 20 21 4.7 0.8 0.0 FFFF%%. 21 22 5.5 3.2 2.2 BFF%.. 22 23 6.2 4.6 3.0 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) 18-Nov-2025 BoM Space Weather Services, Sydney Australia +61-2-9213-8000