[Propagation+Space Weather] Today's Space Weather Forecast Discussion on 2016 Apr 28 1230 UTC

[nw7us@sunspotwatch.com]

This e-mail posting is from the Radio Propagation Reflector that you're 
currently subscribed to.  Refer to the end of this e-mail for directions on how 
to change your subscription options, or to unsubscribe.
_______________________-start-_________________

Here is the current forecast discussion on space weather and geophysical activity, issued 2016 Apr 28 1230 UTC.

Solar Activity

24 hr Summary: Solar activity reached low levels. Region 2535 (N07E22, Cro/beta) remained mostly inactive for the first half of the period. At approximately 28/0126 UTC, this region produced a B8 flare that appeared to have an associated CME, first observed in SOHO/LASCO coronagraph imagery at 28/0216 UTC, departing the northeast limb. Analysis indicated that the Earth may see a weak glancing blow from this CME with an expected arrival early on 1 May. Region 2535 then produced three C1 flares at 28/0342, 0602, 0852 UTC, respectively. An additional CME was observed in coronagraph imagery at approximately 28/0636 UTC, believed to be associated with the C1 flare that occurred at 0602 UTC. Analysis is underway to determine if this CME has an Earth-directed component as well.

Region 2536 (N16E34, Dao/beta) exhibited slight growth in its trailer spots, but dissipation in its intermediate spots, and remained mostly inactive during the period. Region 2537 (S07W56, Dao/beta) continued to experience overall growth and separation between its leader and trailer spots. This region remained mostly inactive during the period, only producing optical subflares. The remaining regions were inactive and stable or in decay.

Forecast: Solar activity is expected to be at very low levels with a chance for C-class flares all three days (28-30 Apr).

Energetic Particle

24 hr Summary: The greater than 2 MeV electron flux continued at normal to moderate levels and the greater than 10 MeV proton flux remained at background values.

Forecast: The greater than 2 MeV electron flux is expected to continue at normal to moderate levels on days one and two (28-29 Apr) and decrease to normal levels on day three (30 Apr) due to electron redistribution from expected CIR and CH HSS effects. The greater than 10 MeV proton flux is expected to continue at background levels.

Solar Wind

24 hr Summary: The solar wind environment was indicative of a slightly enhanced state in the wake of waning positive polarity CH HSS influence. Solar wind speed was variable and measured primarily between 400-500 km/s. The IMF strength ranged predominantly from 4 to 6 nT, while the Bz component was variable between +/- 4 nT. The phi angle was in a mostly positive configuration, with a few isolated deviations into a negative sector.

Forecast: Solar wind parameters are expected to continue at slightly elevated levels early on day one (28 Apr) due to waning influences of the positive polarity CH HSS. A return to more ambient background levels is expected by midday on day one as the CH HSS rotates out of geoeffective position. Conditions are expected to become enhanced later on day two (29 Apr) due to an expected solar sector boundary crossing (SSBC) and preliminary CIR effects. Day three (30 Apr) is likely to see a further enhancement due to the anticipated CIR passage, followed by solar wind speed increases due to connection with a negative polarity CH HSS.

Geospace

24 hr Summary: The geomagnetic field was mostly quiet with an isolated unsettled period, likely in response to prolonged southward Bz orientation.

Forecast: The geomagnetic field is expected to be mostly quiet with an isolated unsettled period possible on day one (28 Apr) as CH HSS influences taper off. Day two (29 Apr) is expected to see geomagnetic responses start quiet, but elevate to unsettled to active levels later in the day as the solar wind environment is enhanced in response to the expected CIR. Day three (30 Apr) is likely to experience responses to minor storm (G1-Minor) levels due to the anticipated CIR and CH HSS effects.

Don't forget to visit our live space weather and radio propagation web site, at: http://SunSpotWatch.com/

Live Aurora mapping is at http://aurora.sunspotwatch.com/

If you are on Twitter, please follow these two users: + https://Twitter.com/NW7US + https://Twitter.com/hfradiospacewx

Get the space weather and radio propagation self-study course, today. Visit http://nw7us.us/swc for the latest sale and for more information!

Check out the stunning view of our Sun in action, as seen during the last five years with the Solar Dynamics Observatory (SDO): https://www.youtube.com/watch?v=zXN-MdoGM9g

We're on Facebook: http://NW7US.us/swhfr

Live data: SunSpotWatch.com

_______________________________________________
Propagation mailing list
Propagation@contesting.com

To change your subscription settings, or to unsubscribe, visit:
http://lists.contesting.com/mailman/listinfo/propagation