SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 15 August, 2026 T-index: 55 Bearings: 201 24 Distance: 1680 km First Mode |--------F r e q u e n c y (MHz)---------| Second Mode 1F 12-15 1E 2 1 5 10 15 20 25 30 35 40 2F 28-33 2E 10 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 14.8 12.9 7.4 ASSXMM MBFF%%%... 9.4 8.3 4.5 00 01 16.4 14.7 8.3 ASSSXM MMBBFF%%%. .. 10.2 9.6 4.9 01 02 16.2 15.9 8.9 SSSXX MMBBBF%%%. ... 10.3 10.4 5.2 02 03 15.7 16.5 9.1 SSSSX MMBBBP%%%. .... 10.4 10.9 5.4 03 04 15.0 16.7 9.2 SSSSX XMBBPP%%.. ... 9.9 11.1 5.4 04 05 14.7 16.6 9.2 SSSSX MMBBPP%%.. .. 9.8 11.0 5.4 05 06 14.4 16.0 8.9 SSSXX MBBBPP%%.. .. 9.5 10.6 5.2 06 07 14.1 14.9 8.4 ASSSXM MBBB%%%... .. 9.3 9.9 4.9 07 08 13.7 13.1 7.6 SSSXMM MBB%%%%... .. 9.2 8.8 4.4 08 09 13.7 9.9 6.0 ASXMMMM MFF%%%%... .. 9.2 6.6 3.5 09 10 11.5 2.2 0.0 XMMMMMMMMF F%%%%..... 7.9 1.4 0.0 10 11 9.1 2.2 0.0 XMMMMMMMF% %%..... 6.4 1.4 0.0 11 12 7.9 2.2 0.0 XMMMMMM%%% ..... 5.6 1.4 0.0 12 13 7.2 2.2 0.0 XMMMMMF%%. ... 5.1 1.4 0.0 13 14 7.0 2.2 0.0 XMMMMM%%%. ... 5.0 1.4 0.0 14 15 6.8 2.2 0.0 XMMMMM%%%. .. 4.9 1.4 0.0 15 16 6.6 2.2 0.0 XMMMMM%%.. .. 4.8 1.4 0.0 16 17 6.5 2.2 0.0 XMMMMM%%.. .. 4.7 1.4 0.0 17 18 6.0 2.2 0.0 XMMMMM%%.. .. 4.6 1.4 0.0 18 19 5.5 2.2 0.0 XMMMM%%%.. .. 4.1 1.4 0.0 19 20 4.9 2.2 0.0 XMMMM%%... . 3.6 1.4 0.0 20 21 4.5 2.2 0.0 XMMMM%.... 3.5 1.4 0.0 21 22 5.5 2.2 0.0 XMMMM%%.. 4.3 1.4 0.0 22 23 11.9 9.4 5.7 ASMMMBF F%%%.. 7.5 5.5 3.6 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) 15-Aug-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000