Space Weather Forecast Headline: Slight chance of isolated Moderate-class flares. Chance of G1/Minor Storm Day 4 (25 Oct).

Analysis of Space Weather Activity over past 24 hours

Solar Activity: Solar activity has been Low with occasional Common-class flares, peaking at C3.5 at 22/0309 UTC. There are two sunspot regions on the disc. One area, in the far west is a relatively straightforward bipolar region. The region in the northwest quadrant, is the biggest region and has increased in magnetic complexity in its intermediate region.

During 21 Oct, a coronal re-alignment was seen in the Sun's northern hemisphere. This appears to have been responsible for at least one Coronal Mass Ejection (CME). Analysis suggests the CME will mostly pass behind Earth's orbit, but given the central location of the likely lift off point, a glancing blow is possible, likely during Day 4 (25 Oct). 

Solar Wind / Geomagnetic Activity:  Solar winds, as measured by SOLAR-1 at L1, showed weak connection the fast winds of a coronal hole Wind speeds have generally been Slightly Elevated, though did become Elevated for a time between 21/1354 UTC and 21/1533 UTC. Interplanetary Magnetic Field, Bt, started moderate and since 21/1755 UTC has been slowly decreasing, becoming generally Weak from 22/0057 UTC. The north-south component, Bz, has been generally weak and southward (negative), but did become weak and northward (positive) for a time between 21/2329 UTC and 22/0347 UTC. Geomagnetic activity was Quiet to Active (Kp 2-4) with a G1/Minor Storm (Kp 5) interval 21/2100-2359 UTC. 

Energetic Particles / Solar Radiation: No solar radiation storms were observed with the count rate of energetic particles persisting at background levels.

Four-Day Space Weather Forecast Summary

Solar Activity: Mainly Low activity is expected to continue, but with a slight chance of increasing to Moderate.

Solar Wind / Geomagnetic Activity: 

During 21 October, a coronal re-alignment was seen in the Sun's northern hemisphere. This appears to have been responsible for at least one CME, alongside the creation of a new coronal hole near centre disc. Analysis of the CME suggests it will mostly pass behind Earth's orbit, but a glancing blow is possible, likely during Day 4 (25 Oct). 

Weak influence from coronal hole fast winds is expected to ease during Day 1 (22 Oct), with the slightly elevated wind speeds erratically declining towards background on Day 1 into Day 2 (22-23 Oct). However, a newly developed coronal hole near centre disc could give fast winds Day 3 into Day 4 (24-25 Oct), although confidence in this is low. MOSWOC Enlil is not providing useful guidance at this point, as it has been over-estimating the current fast winds, and has not yet captured any fast winds from the new coronal hole.

Geomagnetic activity is expected to be Quiet to Unsettled (Kp 0-3), with Active (Kp 4) intervals possible at first. The potential onset of fast winds during Days 3-4 then perhaps bringing Unsettled to Active (Kp 3-4) conditions with a slight chance of G1/Minor storm (Kp 5) intervals, increasing to a chance of G1/Minor storm (Kp 5) intervals during Day 4  (24 Oct).

Energetic Particles / Solar Radiation: No solar radiation storms are forecast with the count rate of energetic particles expected to persist at background levels.