Solar Activity

» 24 hr Summary: Solar activity was at low levels. Weak C-class X-ray activity was observed from Regions 4256 (S19, L=159), 4262 (S13W54, Cso/beta) and 4266 (N16W04, Cro/beta). The spotted regions on the visible disk were mostly quiet and relatively stable. No Earth-directed CMEs were observed in available coronagraph imagery.

» Forecast: Solar activity is expected to remain low over 27-29 Oct.

Energetic Particle

» 24 hr Summary: The greater than 2 MeV electron flux remained at normal to moderate levels during the period. The greater than 10 MeV proton flux was near background levels.

» Forecast: The greater than 2 MeV electron flux is expected to continue at normal to moderate levels, and the greater than 10 MeV proton flux is expected to remain near background levels over 27-29 Oct.

Solar Wind

» 24 hr Summary: Solar wind parameters returned to nominal levels. Total magnetic field strength averaged ~6 nT. No significant periods of southward Bz were observed. Solar wind speeds generally varied between ~350-415 km/s. Phi angle was variable early in the period and mostly steady negative after ~26/1900 UTC.

» Forecast: An enhancement in solar wind parameters is likely later on 27 Oct due to the anticipated influence of a CME that left the Sun on 23 Oct. On 28 Oct and through 29 Oct, influence from a large, positive polarity coronal hole is likely to cause significant increases in both Bt and solar wind speeds.

Geospace

» 24 hr Summary: The geomagnetic field was at quiet levels during the period.

» Forecast: The geomagnetic field is likely to reach active levels later on 27 Oct due to the anticipated arrival of the CME that left the Sun on 23 Oct. G1 (Minor) conditions, with a chance for G2 (Moderate) levels, are likely on 28-29 Oct due to the anticipated onset of influence from a positive polarity coronal hole.


Prepared by:
The U.S. Dept. of Commerce, NOAA, SWPC