Space Weather Forecast Headline: Chance of G1/Minor Geomagnetic Storms Day 1 (17 Sep).

Analysis of Space Weather Activity over past 24 hours

Solar Activity: Solar activity has been Very Low, with no significant flares observed. There are currently two sunspot regions on the visible disc, both simple unipolar spots located in the far west.

There were no Earth directed CMEs observed during the period. 

Solar Wind / Geomagnetic Activity: Solar winds, as measured at L1 by SOLAR-1, indicated a mixture of effects from coronal hole fast winds and possible minor coronal mass ejection influence. Solar wind speeds have been on an erratically downward overall trend, initially Elevated, around 580km/s, with recent observations near 470km/s. The Interplanetary Magnetic Field was Weak varying between 4-7nT. The north-south component was also Weak varying between +7/-5nT, but was predominantly positive (northward).  Geomagnetic activity has been Quiet to Unsettled (Kp 0-3). 

Energetic Particles / Solar Radiation: GOES18 >10MeV proton flux was at normal background levels.

Four-Day Space Weather Forecast Summary

Solar Activity: Solar activity is expected to remain Very Low or Low with only a very slight chance of reaching Moderate levels should any isolated Moderate-class flares occur.

Solar Wind / Geomagnetic Activity: A moderately-fast Coronal Mass Ejection that left the Sun on 14 Sep may pass ahead of Earth orbit early Day 1 (17 Sep), but may give a glancing impact. 

Predominantly Slightly Elevated speeds are expected through the remainder of Day 1 (17 Sep) with a slow, erratic decline thereafter as the high-speed stream eases.

Geomagnetic activity is expected to be mainly Quiet to Unsettled on Day 1 (17 Sep), with a chance of reaching Active (Kp4) or G1/Minor (Kp5) storming levels should any potential Coronal Mass Ejection influence combine with ongoing coronal hole effects. Days 2-4 (18-20 Sep) should see a return to persistently Quiet or Unsettled levels (Kp 1-3).

Energetic Particles / Solar Radiation: GOES18 >10MeV proton flux is at background levels and not expected to change significantly during the forecast period.