April 2016

Propagation Summary
Following disturbed conditions on March16 and17, caused by a high-speed solar wind stream flowing from a geo-effective coronal hole on the sun’s surface, quiet Solar conditions have prevailed for the remaining days of March, with the Solar Flux at 90, The planetary A index at 5, and the K Index at 2.

Propagation Forecast for April
April will start out with disturbed conditions, particularly on April 3 and 4, with the Solar Flux at 90, the A Index at 30 and the K Index at 6, which usually indicates storm conditions.   Calmer conditions should prevail until April 10-14 when storm conditions are likely, but quiet to unsettled conditions are expected from April16th.
( http://www.swpc.noaa.gov/products/27-day-outlook-107-cm-radio-flux-and-geomagnetic-indices )

Meteor Showers in April
The Lyrids are due on April 21-22, but the 2016 showers are forecast to only be 10-15 meteors per hour, which may not be much use for meteor scatter propagation, but in past years these meteor showers have been at the rate of around 100 per hour.
( http://earthsky.org/astronomy-essentials/earthskys-meteor-shower-guide#lyrids )

Radio Propagation Blog
Bob Zanotti and Bob Thomer, known as the 2 Bobs on Swiss Radio Internetional have done a number of podcasts on switzerlandinsound.com , featuring some re-recordings and some original programming of their long running Dx programme.  An interesting edition about shortwave propagation can be found here
The next propagation report will be in June. Links to propagation articles can be found on my propagation links page at : www.jameswelsh.org.uk 

August 2013

Propagation Summary

Solar activity was low during the second half of July, apart from three C3 Solar flux events.  The first two occurred at 15, and 16 July, followed by a third event on 21^st July.  The Solar flux also reached high levels every day during this period.  The Geomagnetic field ranged from quiet to minor storm levels, peaking on 15 July, then unsettled to active conditions were observed from 20 July onwards.

Propagation Forecast up to 17 August 2013

Solar activity is expected to remain low with a chance for isolated minor radio blackout conditions throughout the period due to active region flare activity.  The Solar Flux is expected to be at high levels through 20 August, due to a Coronal Hole High Speed Stream.  The Geomagnetic Field is expected to be generally quiet to unsettled for the majority of the period with the exception of 9-11 August and 14-15 August due to a recurrent Coronal Hole High Speed Stream.  Weekly updates to this forecast are available at: http://www.swpc.noaa.gov/ftpdir/weekly/WKHF.txt

The Sun's 2013 Solar Activity Peak Is Weakest in 100 Years

Though the sun is currently in the peak year of its 11-year solar weather cycle, our closest star has been rather quiet over all, scientists say.  This year's solar maximum is shaping up to be the weakest in 100 years and the next one could be even more quiescent, scientists said  "It's the smallest maximum we've seen in the Space Age," David Hathaway of NASA's Marshall Space Flight Center in Huntsville, Ala., told reporters in a teleconference.  The full article can be found at: http://www.space.com/21937-sun-solar-weather-peak-is-weak.html   (Via Mike Terry) 

Links to these articles and more can be found at: http://www.jameswelsh.org.uk

July 2013

Propagation Summary

Solar activity was at low to moderate levels during the second half of June.  The majority of the low level activity was on 18-22 June,  then high levels were observed on 23 June in response to coronal hole high speed Stream. 

Geomagnetic field activity was at quiet to active levels. The period began with quiet levels on 17-19 June, but due to an increase in solar wind speeds, the geomagnetic field responded with unsettled to active periods late on 20 June.  The conditions then worsened to minor storm periods on 21-23 June due to another coronal mass ejection.

Propagation Forecast

Mostly quiet conditions are expected from 30 June to 04 July. By 05-06 July, quiet to unsettled conditions are expected with the arrival of another Coronal Hole High speed Stream Quiet conditions are once again expected from 07-16 July. Quiet to unsettled conditions are expected on 17 July with unsettled to active levels from 18-20 July due to Coronal Hole activity once again.  

Solar Observatory Launched:

NASA's newest space telescope, a unique solar observatory named "IRIS", is orbiting Earth  following a successful launch on June 27^th.  Leaving from the Vandenberg Air Force Base in California, an Orbital L-1011 aircraft carried IRIS inside a Pegasus XL rocket out over the Pacific Ocean, where the rocket separated from the belly of the airplane and blasted into space.  http://www.swpc.noaa.gov/ftpdir/weekly/WKHF.txt 

Shortwave Central

You can find up to date forecasts for shortwave conditions and articles about broadcast and amateur radio at: http://mt-shortwave.blogspot.co.uk/

June 2013

Propagation Summary

Solar activity reached high levels during the second half of May, in fact the highest levels of activity since 2013 began.  Between 13 and 14 May, newly-numbered Region 1748 produced 2 flares, producing several radio emissions.  Solar activity remained at high levels on 15 May, but activity declined to moderate levels on 16 May with a single M1 Flare.  Moderate levels continued through 17 May and low levels of activity prevailed until a M5 Coronal Mass ejection hit Earth's magnetic field on May 24th at around 1800 UTC.

Geomagnetic field activity reached minor to major storm levels on 20 May in response to the 17 May coronal mass ejection.  More information about Solar Flare classes can be found at: http://spaceweather.com/glossary/flareclasses.html

Forecast of Solar and Geomagnetic Activity up to 15 June 2013

Solar activity is expected to be low to moderate throughout the forecast period. High levels of activity are possible on 25 May and again after 7 June.  The Solar flux is expected to be at high levels from 24-31 May associated with a recurrent Coronal Hole High Speed Stream.  In the absence of any Earth-directed coronal mass ejections, the remainder of the forecast period is expected to be characterized by quiet to unsettled levels of activity with the possible exception of 28 May, when another Coronal Hole high speed stream brings active levels.  Daily updates are available at: http://www.swpc.noaa.gov/ftpdir/weekly/WKHF.txt

 

The current prediction for Sunspot Cycle 24 gives a smoothed sunspot number maximum of about 66 in the autumn of 2013.  The smoothed sunspot number has already reached 67 (in February 2012) due to the strong peak in late 2011, so the official maximum will be at least this high and this late. We are currently over four years into Cycle 24. The current predicted and observed size makes this the smallest sunspot cycle since Cycle 14 which had a maximum of 64.2 in February of 1906. From: http://solarscience.msfc.nasa.gov/predict.shtml

April 2013

Propagation Summary

Solar activity was very low to moderate during late March. Low activity dominated the week with low level C-class flares observed on 18-20 and 23-24 March.  The Solar Flux was mostly low, increasing to moderate levels on 18-20 March.

Geomagnetic field activity was at quiet to active levels. The period began with mostly quiet conditions.  An increase to quiet to active levels was observed on 21 March due to effects from two Coronal Mass Ejections. (CME’s) on 17 March. Quiet conditions prevailed for the remainder of the period with the exception of an isolated active period at the close of 23 March.

This increase in activity was possibly related to the weak CME observed on 19 March.

 

Forecast of Solar and Geomagnetic Activity up to 20 April 2013

Solar activity is expected to be very low to low throughout the period. A slight chance for M-class flare activity is possible from 01-13. High levels of activity are expected from 29 March-04 April due to recurrent Coronal Hole high speed stream.   A return to normal to moderate levels is expected for the remainder of the period.  Geomagnetic field activity is expected to begin the period at mostly quiet levels. Quiet to active conditions, with a chance for minor storm periods are expected on 28-30 March.

 

Solar Cycle 24 Progression

The Solar Cycle 24 progression charts show that the average sunspot numbers continue to remain well below estimated levels.  The last major peak was in late 2011 which gave an average sunspot number of 95.  This figure dropped to around 30 in early 2012, but is now around the 55 mark. This is one of the most uneventful solar cycles since records began.
http://www.swpc.noaa.gov/SolarCycle/

 

Lyrid Meteor Showers

On April 18-15, there a major Lyrid meteor shower is forecast.  For details of how meteor scatter works, here is a link to an article: http://www.qsl.net/g3wzt/g3wzt_ms.html

March 2013

Propagation Summary.

Conditions during February have been fairly quiet as predicted with sunspot activity well below predicted levels.

Forecast of Solar and Geomagnetic Activity until 23 March 2013

Solar activity is expected to be at very low to low levels throughout the forecast period with a slight chance for an M-class event after 10 March. The Solar flux is expected to be at normal to moderate levels.  Geomagnetic field activity is expected to be at quiet levels through the majority of the forecast period. Unsettled levels are predicted for 01 and 21 March when recurrent coronal hole high speed streams are forecast.

 Solar Cycle 14 Peak Prediction

The current prediction for Sunspot Cycle 24 gives a smoothed sunspot number maximum of about 66 in the autumn of 2013. The smoothed sunspot number has already reached 67 (in February 2012) due to the strong peak in late 2011 so the official maximum will be at least this high and this late.  We are currently over four years into Cycle 24. The current predicted and observed size makes this the smallest sunspot cycle since Cycle 14 which had a maximum of 64.2 in February of 1906. http://solarscience.msfc.nasa.gov/predict.shtml

The Boulder K Index

The ‘K’ Index is a good way of predicting shortwave conditions.  Usually, if the K Index reaches 5, there is usually a shortwave blackout due at some time.  A live and updated chart of the K index can be found at: http://www.solarham.net/planetk.htm

 

February 2013

Propagation Summary.
Sunspot activity was predominantly at low levels with very low levels observed on 17 January. The largest flares of the period were on 07 and 11 January which was a c5 flare.  Then on 16 January, a long duration C2 flare occurred.  The Solar Flux was at moderate levels on 14-16 January and again on 19-20^th.  High levels were observed n response to a shock arrival from a Coronal Mass ejection on 13 January. Geomagnetic field activity ranged from quiet to active. 

Forecast for Solar and Geomagnetic Activity until 16 February

Solar activity is expected to be at very low to low levels until 30 January.  A chance for M-class flares exists from 31 January through to 15 February.  By 16 February, very low to low levels are expected.  The Solar Flux is expected to be at normal to moderate levels until 23 January, then on 24-25 January there is a chance of an increase to high levels.  Low to normal levels should then prevail 26 January to 9 February until the end of the forecast period.  Geomagnetic field activity is expected to be mostly quiet through the forecast period with unsettled periods expected on 23 January and 9-10 February.

From: http://www.swpc.noaa.gov/ftpdir/weekly/WKHF.txt

 

Sun to Skip Solar Cycle 25?

According to three independent studies of the Sun's interior, visible surface and corona, solar cycle 25 will have significantly reduced activity, or may not even appear at all. “This is highly unusual and unexpected,” says Frank Hill, associated director of the National Solar Observatory's (NSO) Solar Synoptic Network. “But the fact that three completely different views of the Sun point in the same direction is a powerful indicator that the sunspot cycle may be going into hibernation.”  You can read this article in full by Dr Emily Baldwyn of Astronomy Now Magazine at: http://www.astronomynow.com/news/n1106/15solar/