SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 17 December, 2025 T-index: 95 Bearings: 201 24 Distance: 1680 km First Mode |--------F r e q u e n c y (MHz)---------| Second Mode 1F 13-21 1E 2 1 5 10 15 20 25 30 35 40 2F 29-41 2E 10 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 13.2 15.8 9.2 SSXXX BBBPP... 7.9 10.5 5.3 00 01 14.3 17.1 9.8 ASSXX XBBBPPP... 8.4 11.4 5.7 01 02 15.0 18.0 10.3 ASSXX XBBBPPPE.. 8.9 12.0 6.0 02 03 15.5 18.5 10.5 SSSX XXBBBPPE.. . 9.3 12.3 6.1 03 04 15.6 18.7 10.6 SSSX XXBBBPPP.. .. 9.6 12.5 6.1 04 05 16.3 18.5 10.5 SSSX XXBBBBPP%. ... 9.8 12.4 6.1 05 06 15.6 18.1 10.3 ASSSX XXBBBPPP%. ... 9.6 12.1 6.0 06 07 15.2 17.2 9.9 ASSSX XMBBBPP%%. ... 9.4 11.5 5.8 07 08 14.6 16.0 9.3 SSSSX MBBBPP%%.. .. 9.2 10.6 5.4 08 09 14.2 14.1 8.4 ASSSXM MBBB%%%%.. .. 9.2 9.2 5.0 09 10 13.1 11.1 6.9 SSMMMM MFF%%%%... . 8.9 6.9 4.2 10 11 12.6 2.4 0.0 MMMMMMMMMM MF%%%%.... . 8.6 0.0 2.0 11 12 12.0 2.4 0.0 XMMMMMMMMM F%%%%%.... 8.4 1.6 0.0 12 13 11.9 2.4 0.0 XMMMMMMMMM F%%%%..... 7.9 1.6 0.0 13 14 12.0 2.4 0.0 XMMMMMMMMF F%%%%.... 7.7 1.6 0.0 14 15 12.4 2.4 0.0 XMMMMMMMMF FF%%%..... 7.7 1.6 0.0 15 16 12.2 2.4 0.0 XMMMMMMMMF FF%%%.... 7.6 1.6 0.0 16 17 11.3 2.4 0.0 XMMMMMMMFF F%%%.... 7.1 1.6 0.0 17 18 9.7 2.4 0.0 XMMMMMMMF% %%%.... 6.7 1.6 0.0 18 19 9.0 2.4 0.0 XMMMMMMM%% %%..... 6.4 1.6 0.0 19 20 8.1 2.4 0.0 XMMMMMMF%% %.... 6.0 1.6 0.0 20 21 8.0 2.4 0.0 XMMMMMM%%% %.... 6.1 1.6 0.0 21 22 10.3 10.7 6.6 ASSXMBB %%%.... 7.0 7.1 3.8 22 23 12.3 13.9 8.2 ASSXXB BBP%%... 7.6 9.2 4.8 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) 17-Dec-2025 BoM Space Weather Services, Sydney Australia +61-2-9213-8000