[Propagation+Space Weather] Today's Space Weather Forecast Discussion on 2015 Sep 03 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 2015 Sep 03 1230 UTC.

Solar Activity

24 hr Summary: Solar activity reached low levels. Though now around the western limb, Region 2407 produced the largest flare of the period, a C1/Sf flare at 03/1137 UTC. Region 2409 (N04E33, Dro/beta) was stable and inactive. Newly numbered Region 2410 (S19E36, Bxo/beta) was also stable and managed only low level B-flare activity.

A coronal mass ejection (CME) from the NW limb was first noted in available LASCO-C2 imagery at 02/1325 UTC, however analysis of SDO/AIA and GONG/H-alpha imagery suggests this was an event from around the limb and not likely to have an Earthward component. No Earth-directed CMEs were observed in available coronagraph imagery.

Forecast: Solar activity is expected to remain very low with a slight chance for C-class flares all three days (03-05 Sep).

Energetic Particle

24 hr Summary: The greater than 2 MeV electron flux was at normal to high levels with a maximum flux of 2790 pfu at 02/1515 UTC. The greater than 10 MeV proton flux was at background levels.

Forecast: The greater than 2 MeV electron flux is expected to be at normal to moderate levels on days one and two (03-04 Sep) as a coronal hole high speed stream (CH HSS) has become geoeffective. The 2 MeV electron flux may see increased levels of normal to high on day three (05 Sep) as the CH HSS effects begin to wane. The greater than 10 MeV proton flux is expected to continue at background levels.

Solar Wind

24 hr Summary: The solar wind parameters measured at the ACE spacecraft were benign until about 02/1522 UTC when the phi angle changed from negative to positive due to the anticipated solar sector boundary crossing (SSBC) ahead of the co-rotating interaction region (CIR) associated with a positive polarity coronal hole. Wind velocities increased from near 380 km/s to 420 km/s as the CIR came into play. Winds have since gradually increased as the CH HSS is beginning to settle in as the dominant regime. Total magnetic field strength increased from 3-5 nT to about 8 nT with the CIR and has since decreased back to near 5 nT. The Bz component was mostly southward; however, the maximum deflection managed only -5 nT for a brief period when the CIR began.

Forecast: Solar wind speeds are expected to continue at higher than ambient levels for the next two days (03-04 Sep) before beginning to wane as Earth begins to exit the CH HSS on day three (05 Sep).

Geospace

24 hr Summary: The geomagnetic field was quiet to unsettled.

Forecast: The geomagnetic field is expected to have periods of unsettled to active conditions on day one (03 Sep) due to CH HSS influences. Day two (04 Sep) is expected to see quiet to unsettled conditions as the CH HSS effects continue. Day three (05 Sep) is expected to be mostly quiet, with isolated unsettled periods as CH HSS effects begin to wane.

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