(Source: ARRL via Mike Terry)
NOAA’s Space Weather Prediction Center (SWPC) has issued a strong (G3) geomagnetic storm watch for September 7 through September 9. The SWPC said the watch for September 7 remains in effect due to the arrival of a coronal mass ejection (CME) and the effects of a CME on September 4.
“Additionally, a G3 watch is now in effect for the 8 and 9 September UTC days in anticipation of the arrival of another CME associated with the X9.3 flare (R3 — strong radio blackout) on 6 September at 1202 UTC (0802 ET),” the SWPC said early on September 7. “Analysis indicates likely CME arrival late on 8 September into early 9 September.” The September 6 flare is being called the strongest in more than a decade.
Its effect on HF radio propagation has adversely affected the Hurricane Watch Net (HWN), currently operating on 20 and 40 meters as Hurricane Irma sweeps through the Caribbean.
As of September 7 at 1400 UTC, the solar flux index stood at 127, the sunspot number at 27, the A index at 11, and the K index at 4. All HF conditions are being deemed as no better than fair. The possibility of extended auroral displays could work to the benefit of VHF and UHF operators who aim their antennas north to take advantage of “buzz” mode. SWPC posts a 30-minute forecast of visible aurora.[…]
Also, check out Tamitha Skov’s forecast on YouTube:
Last night, I tested a couple of HF radios and all but the strongest shortwave broadcasters (WRMI, RHC) were wiped out. Even the strong stations sounded like weak DX. This is truly an HF blackout.