SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 21 July, 2026 T-index: 65 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 28-32 2E 10 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 14.9 12.3 7.2 SSSMMM MBFF%%%... . 9.5 7.8 4.4 00 01 16.6 14.4 8.2 ASSSXM MMBBFF%%%. ... 10.5 9.3 4.9 01 02 16.5 15.6 8.8 SSSXX MMBBBF%%%% .... 10.7 10.2 5.2 02 03 16.2 16.3 9.1 SSSSX MMBBBB%%%% ..... 10.8 10.7 5.3 03 04 15.2 16.5 9.2 SSSSX MMBBBP%%%. ... 10.2 10.9 5.4 04 05 15.1 16.3 9.1 SSSSX MMBBBP%%.. ... 10.0 10.8 5.3 05 06 14.6 15.7 8.8 SSSXX MMBBP%%%.. ... 9.7 10.4 5.2 06 07 14.6 14.5 8.3 ASSSXM MBBB%%%%.. ... 9.6 9.7 4.8 07 08 14.4 12.6 7.3 SSSXMM MBFF%%%... ... 9.5 8.4 4.3 08 09 14.1 8.6 5.3 SSMMMMM MFFF%%%... .. 9.4 5.7 3.1 09 10 11.1 2.2 0.0 XMMMMMMMMF F%%%..... 7.7 1.5 0.0 10 11 8.5 2.2 0.0 XMMMMMMF%% %..... 6.0 1.5 0.0 11 12 7.4 2.2 0.0 XMMMMMF%%. .... 5.2 1.5 0.0 12 13 6.8 2.2 0.0 XMMMMM%%%. ... 4.8 1.5 0.0 13 14 6.3 2.2 0.0 XMMMMF%%.. .. 4.7 1.5 0.0 14 15 6.1 2.2 0.0 XMMMMF%%.. . 4.6 1.5 0.0 15 16 6.1 2.2 0.0 XMMMMF%%.. . 4.6 1.5 0.0 16 17 5.9 2.2 0.0 XMMMM%%%.. . 4.5 1.5 0.0 17 18 5.6 2.2 0.0 XMMMM%%%.. . 4.2 1.5 0.0 18 19 5.3 2.2 0.0 XMMMM%%%.. . 3.9 1.5 0.0 19 20 4.8 2.2 0.0 XMMM%%%... 3.4 1.5 0.0 20 21 4.7 2.2 0.0 XMMM%%%... 3.4 1.5 0.0 21 22 5.8 2.2 0.0 XMMMM%%... 4.3 1.5 0.0 22 23 11.0 7.9 4.9 SMMMMFF %%%.. 6.8 0.0 3.3 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) 21-Jul-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000