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Here is the current forecast discussion on space weather and geophysical activity, issued 2015 Apr 23 1230 UTC.
Solar Activity
24 hr Summary: Solar activity was at moderate levels once again. Region 2322 (N11, L=117), now just beyond the west limb, produced the largest flare of the period, a long duration M1/Sf flare at 23/1007 UTC, as well as an associated Type II radio sweep (664 km/s est. shock speed). Region 2326 (N20W71, Cao/beta) redeveloped from an area of enhanced plage to become a Cao spot group as it reached the west limb. This region was also responsible for a few low-level C-class flares during the period. Region 2331 continued to show separation between its leader and trailer spots, with slight growth and consolidation observed in its leader spots. The remaining regions were either stable or decaying. No coronal mass ejections (CMEs) on the Sun-Earth line were observed over the period. However, as imagery becomes available, any CME associated with the M1 flare will be analyzed for potential impacts at Earth.
Forecast: Solar activity is expected to be low with a chance for M-class (R1- Minor) flares over the next three days (23-25 Apr). Region 2322 remains the region most likely to produce M-class (R1-Minor) flares until it transits far enough around the west limb to no longer pose a flare risk. Probabilities will decrease slightly for days two and three (24-25 Apr) once it rotates around the limb.
Energetic Particle
24 hr Summary: The greater than 2 MeV electron flux was at normal to moderate levels, due to elevated but decreasing solar wind velocities. The greater than 10 MeV proton flux was slightly enhanced, but remained well below the S1-Minor alert threshold.
Forecast: The greater than 2 MeV electron flux is expected to be at normal to moderate to levels for days one through three (23-25 Apr). The greater than 10 MeV proton flux is likely to remain slightly enhanced over the next three days (23-25 Apr), but remain below the S1-Minor alert threshold, barring any enhancements from the recent long duration M1/Sf flare.
Solar Wind
24 hr Summary: Solar wind parameters reflected waning coronal hole high speed stream (CH HSS) effects. Solar wind velocities exhibited a slow but steady decrease from near 550 km/s to end of period speeds just under 430 km/s. IMF total field averaged near 5 nT, while Bz saw a maximum southward deflection to -4 nT. Phi angle remained in a positive (away) orientation for most of the period.
Forecast: Solar wind parameters are expected to continue to show waning CH HSS effects over the next three days (23-25 Apr). EPAM values suggest there is still a chance the CME from 18 Apr may arrive at Earth, but effects are likely to be limited based on the relatively slow transit time it has taken to reach Earth.
Geospace
24 hr Summary: The geomagnetic field was quiet to unsettled levels, with an isolated active period from 23/0300-0600 UTC, as CH HSS effects continue to wane.
Forecast: The geomagnetic field is expected to be at quiet to unsettled levels with occasional active periods for day one (23 Apr) as residual CH HSS effects continue. Mostly quiet conditions are forecast for day two (24 Apr). Unsettled to active conditions are expected to return on day three (25 Apr) from disturbances following a solar sector change to a negative orientation.
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![Today's Space Weather Forecast Discussion - 2015 Apr 23 20:07 UTC]()
Live data: SunSpotWatch.com
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