SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Geraldton Perth Date: 13 February, 2026 T-index: 75 Bearings: 162 341 Distance: 373 km First Mode |--------F r e q u e n c y (MHz)---------| Second Mode 1F 52-62 1E 24 1 5 10 15 20 25 30 35 40 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 5.4 5.0 3.1 BB%%.. 00 01 5.7 5.5 3.4 BB%%.. 01 02 6.3 5.9 3.6 ABF%%.. 02 03 6.8 6.1 3.7 ABB%%.. 03 04 7.1 6.2 3.7 ABBF%.. 04 05 7.2 6.2 3.7 ABBF%%. . 05 06 7.3 6.0 3.6 ABBF%%. . 06 07 7.1 5.8 3.5 ABFF%%. . 07 08 6.9 5.4 3.3 BBF%%%. 08 09 6.6 4.7 3.0 ABFF%%.. 09 10 6.2 3.8 2.4 BFFF%%. 10 11 5.8 0.8 0.0 FFFFF%%.. 11 12 5.5 0.8 0.0 FFFFF%%. 12 13 5.1 0.8 0.0 FFFFF%.. 13 14 4.8 0.8 0.0 FFFF%%. 14 15 4.7 0.8 0.0 FFFF%%. 15 16 4.6 0.8 0.0 FFFF%%. 16 17 4.5 0.8 0.0 FFFF%.. 17 18 4.3 0.8 0.0 FFFF%.. 18 19 4.1 0.8 0.0 FFFF%. 19 20 3.8 0.8 0.0 FFF%.. 20 21 3.7 0.8 0.0 FFF%. 21 22 4.1 2.5 1.7 AFF%. 22 23 4.7 4.2 2.7 AB%%. 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) 13-Feb-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000