Propagation News 12 January 2014

Solar activity for the last three weeks was low on most days, moderate on some days and high on the occasional day. Solar activity was high on the 1st and the 7th of January. An X1 class solar flare took place on the 7th, this was the first X class flare since the 19th of November last year. Solar flux levels initially declined slight lower than forecast, reaching 116 units on Boxing Day and then climbed higher than forecast to peak at 237 units, that’s the highest daily figure for this sunspot cycle and also since August 2002. By the 9th levels had declined to 184. The 90 day solar flux average on the 9th was 152 units, which is also the highest for this cycle. X-ray flux levels increased from B3.5 units at the end of the year to C1.8 units by the 5th of January. Geomagnetic activity was quiet every day except for the 1st and 2nd of January which increased to an Ap index of 15 and 18 respectively. That was the only coronal hole disturbance to take place.

Finally, the solar forecast for the coming week. While the large sunspot region is still in view that rotated into view on the 1st solar activity could be at moderate to high levels, however, as the region rotates out of view towards next weekend solar activity is expected to decline to low levels. Solar flux levels should decline to around 130 units. Geomagnetic activity is expected to be at low levels unless an Earth directed coronal mass ejection increases activity. No coronal hole disturbances are expected. MUFs during daylight hours at equal latitudes should be around or slightly above 30MHz. Darkness hour lows should be about 8MHz. Paths this week to the Middle East should have a maximum usable frequency with a 50 per cent success rate of around 30MHz. The optimum working frequency with a 90 per cent success rate will be about 25MHz. The best time to try this path will be between 0900 and 1500 hours UTC.

And that’s all for this week from the propagation team.

Category: GB2RS Propagation News