Monday, January 06, 2014

Solar Flux Finally Hits 200+

In the past few days, the various observatories taking 10.7 cm solar flux data have all had readings above 200 for the first time in Cycle 24.

The highest solar flux measurement was 262, taken at the Dominion Radio Astrophysical Observatory on January 3. The "WWV" solar flux peaked at 218, and on January 5 it was still 204.

These are uncorrected solar fluxes, and the Earth reached perihelion for the year on January 4. Even so, when corrected to 1 Astronomical Unit, the higher values exceed 200.

Low mid-latitude K indices have helped HF propagation, though strong aurora and polar absorption have degraded high-latitude paths. This is due mostly to a coronal hole, followed by a minor proton storm caused by several events on the sun.

Forecasts are for a minor magnetic storm in the higher latitudes, as ejected coronal mass from several solar disturbances does a near miss of this planet. Watch the K index, even though it is currently still at a nice low 2.

We may also see sudden HF blackouts if the expected class M solar flares materialize.  The current probability of this is currently estimated to be around 75%.

Today saw a brief opening of strong signals up to about 35 MHz here in California. Distances were consistent with F2 propagation.  Since these are business and public safety radios using FM and designed for local coverage, it's likely that stations optimized for ultra-weak-signal F2 propagation worked higher up than this.

Obviously, Cycle 24 is having the second peak predicted by many, as the other magnetic pole on the sun changes polarity. With spring DX coming, this cycle is not out of surprises yet.