SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: PortHedlandPerth Date: 16 May, 2025 T-index: 90 Bearings: 191 12 Distance: 1323 km First Mode |--------F r e q u e n c y (MHz)---------| Second Mode 1F 17-20 1E 4 1 5 10 15 20 25 30 35 40 2F 35-39 2E 13 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 15.1 11.1 6.0 ASXMMMM MFFFF%%... 9.7 6.5 3.6 00 01 17.5 13.1 6.9 SSXMMM MMBFFFF%%% ... 11.1 7.8 4.1 01 02 17.9 14.3 7.4 SSSXMM MMMBFFF%%% .... 11.6 8.6 4.4 02 03 17.9 15.0 7.7 ASSXMM MMMBBFF%%% .... 11.6 9.0 4.6 03 04 17.5 15.3 7.8 ASSXXM MMMBBFF%%% ... 11.3 9.2 4.6 04 05 17.0 15.1 7.8 ASSXXM MMBBBF%%%. .. 11.1 9.1 4.6 05 06 16.8 14.6 7.5 ASSXMM MMMBFF%%%. .. 11.0 8.8 4.5 06 07 17.2 13.6 7.1 SSSXMM MMMFFFF%%% ... 11.1 8.2 4.2 07 08 17.3 12.0 6.4 ASSXMMM MMMFFFF%%% ... 11.1 7.2 3.8 08 09 16.3 8.8 5.0 ASXMMMMM MMFFFF%%%. .. 10.5 5.2 3.0 09 10 13.0 2.1 0.0 XMMMMMMMMM FF%%%.... 8.6 1.3 0.0 10 11 10.3 2.1 0.0 XMMMMMMMFF %%%... 6.8 1.3 0.0 11 12 8.4 2.1 0.0 XMMMMMMF%% ... 5.7 1.3 0.0 12 13 7.3 2.1 0.0 XMMMMMF%%. .. 5.1 1.3 0.0 13 14 6.8 2.1 0.0 XMMMMM%%.. . 4.9 1.3 0.0 14 15 6.4 2.1 0.0 XMMMMF%%.. 4.7 1.3 0.0 15 16 6.4 2.1 0.0 XMMMMF%%.. 4.6 1.3 0.0 16 17 6.1 2.1 0.0 XMMMMF%... 4.4 1.3 0.0 17 18 5.9 2.1 0.0 XMMMM%%... 4.2 1.3 0.0 18 19 5.6 2.1 0.0 XMMMM%%... 3.9 1.3 0.0 19 20 5.5 2.1 0.0 XMMMM%%... 3.8 1.3 0.0 20 21 5.1 2.1 0.0 XMMMM%... 3.7 1.3 0.0 21 22 5.7 2.1 0.0 XMMMM%%.. 4.2 1.3 0.0 22 23 11.2 6.3 3.7 AMMMMMFF F%%.. 7.0 0.0 2.5 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) 16-May-2025 BoM Space Weather Services, Sydney Australia +61-2-9213-8000