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Here is the current forecast discussion on space weather and geophysical activity, issued 2015 Nov 19 1230 UTC.

Solar Activity

24 hr Summary: Solar activity was at low levels due to a C1 flare at 18/2009 UTC that occurred from an active region at or just beyond the NE limb as seen in GOES-15/SXI imagery. Some spots associated with the active region were just becoming visible in SDO/HMI-Intensitygrams late in the period, but assignment as a new spot region awaits the regions rotation further onto the visible disc for proper evaluation and classification. Region 2456 (N06W08, Dai/beta) underwent some dissipation amongst its trailer spots early in the period, before emerging again later in the period as regrowth. Despite the structural variability of the region, it remained in a simple bipolar configuration and was inactive. All remaining regions were also inactive or in decay.

An enhancement in the plage field of spotless Region 2453 (N06W74) was observed in SDO/AIA-304 imagery and coincided with a coronal disruption noted in SDO/AIA-193 imagery at about 18/1830 UTC. This activity appeared to be associated with a coronal mass ejection (CME) from the W limb, first observed in SOHO/LASCO-C2 imagery at 18/1900 UTC. Analysis indicates the CME will be off the Sun-Earth line. No Earth-directed CMEs were observed in SOHO/LASCO coronagraph imagery during the period.

Forecast: Solar activity is expected to continue at very low levels, with a chance for C-class flares over the next three days (19-21 Nov), primarily due to the flare probabilities of Region 2456 and the active region near the NE limb.

Energetic Particle

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

Forecast: The greater than 2 MeV electron flux is expected to be at normal to moderate levels on day one (19 Nov). On days two and three (20-21 Nov), an increase to high levels is likely as higher solar winds interact with Earths magnetosphere. The greater than 10 MeV proton flux is expected to persist at background levels throughout the forecast period.

Solar Wind

24 hr Summary: Solar wind velocity and interplanetary magnetic field (IMF) parameters, as measured by the ACE spacecraft, were indicative of near background conditions at the beginning of the period. At about 18/1925 UTC, the total magnetic field increased from 6 nT to 12 nT, wind speeds increased from around 415 km/s to near 460 km/s, and Bz saw a maximum southward deflection to near -11 nT; indicating a likely shock passage from the anticipated CME of 15-16 Nov. After the shock passage, total magnetic field strength steadily decreased and ended the period near 4 nT. As the CME passed through ACE, solar wind speed reached a maximum velocity of about 500-530 km/s from 19/0000-19/0030 UTC before it started to decrease, ending the period near 430 km/s. The phi angle was predominantly negative (towards the Sun) throughout most of the period, with the exception of a brief rotation into the positive (away from Sun) sector between about 19/0145-0425 UTC.

Forecast: Solar wind parameters are expected to remained enhanced on day one (19 Nov) under the continued influence of the coronal hole high speed stream (CH HSS) and CME effects. Day two (20 Nov) will likely see the influences of both the CME and CH HSS wane, with near ambient conditions expected by the end of the day three (21 Nov).

Geospace

24 hr Summary: The geomagnetic field began the period at quiet to unsettled levels, before conditions elevated to minor (G1-Minor) storming during the 18/2100-18/2400 synoptic period. A geomagnetic sudden impulse (70 nT deviation from quiet day curve) was recorded by the Wingst magnetometer at approximately 18/2010 UTC, likely a result of the CME shock arrival at Earth. The geomagnetic response decreased to active conditions during the 19/0000-19/0300 UTC synoptic period, and became quiet to unsettled afterwards.

Forecast: Even though conditions have become more settled, the geomagnetic field is still expected to experience active periods, and remains likely to see a period of minor (G1-Minor) storm levels on day one (19 Nov) due to the continued, but waning, combined influences from the negative polarity CH HSS and the CME. Days two and three (20-21 Nov) are expected to see conditions trend towards quiet, with occasional unsettled periods, under a more ambient solar wind and IMF environment.

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