Issued: 2013 Nov 12 1230 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # Solar Activity .24 hr Summary... Solar activity was low. Region 1890 (S11W49, Ekc/beta-gamma-delta) produced several C-class flares, including the largest event of the period, a C5/Sf at 11/1701 UTC. This region exhibited consolidation in its trailer spots and minor separation in the leader spots, but maintained its beta-gamma-delta configuration. Region 1897 (S18E57, Ekc/beta-gamma) also produced a few C-class flares and grew in size and complexity. This new region appears to be fairly large and dynamic, although the exact size and magnetic complexity remain difficult to determine given its proximity to the limb. The other regions on the visible disk were stable or decaying and were unremarkable. A long-duration C3 flare occurred at 12/0527 UTC and had an associated coronal mass ejection (CME). Initial analysis indicated most of the ejected had a primarily southwesterly trajectory. Analysis is on-going to determine if there is any Earth-directed component of the CME. .Forecast... Solar activity is likely to be moderate (R1-R2 Minor-Moderate) with a chance for X-class (R3-Strong) flares for the next three days (12-14 Nov) with Regions 1890 or 1897 being the likely source. Energetic Particle .24 hr Summary... The greater than 2 MeV electron flux at geosynchronous orbit was at normal to moderate levels. The greater than 10 MeV proton flux at geosynchronous orbit remained enhanced from the 08 Nov event, but well below the S1 (Minor) threshold. .Forecast... The greater than 2 MeV electron flux is expected to be at normal to high levels for the period (12-14 Nov) as the result of coronal hole high speed stream (CH HSS) effects. A chance exists for the greater than 10 MeV proton flux to reach S1 (Minor) solar radiation storm levels for the next three days (12-14 Nov) as Region 1890 traverses westward and into a more favorable location to produce a proton event. Solar Wind .24 hr Summary... Solar wind parameters, measured at the ACE spacecraft, were consistent with diminishing CH HSS influence. Solar wind speeds began the period near 550 km/s, but steadily decreased by the end of the period to approximately 410 km/s. The total field strength ranged from 2 nT to 8 nT for most of the period and settled in at approximately 5 nT by the end of the period. The Bz component fluctuated between -5 nT to +5 nT, ending the period at +3 nT. Following the transition from negative (toward) to positive (away) orientation around 11/1743 UTC, the phi angle of the solar wind remained in a mostly positive (away) orientation to finish the period. .Forecast... Solar wind conditions are expected to return to background conditions on day one (12 Nov) as CH effects diminish. Day two (13 Nov) may see conditions consistent with combined glancing blow CME profiles from the events on 8 and 10 Oct, though speeds will be modest and unremarkable. Day three (14 Nov) should see ambient background solar wind conditions. Geospace .24 hr Summary... The geomagnetic field was at quiet to unsettled levels due to waning CH HSS effects. .Forecast... The geomagnetic field is expected to be at quiet levels for day one (12 Nov) as solar winds return to background conditions. Quiet to unsettled levels are expected to return on day two (13 Nov) as residual CH HSS effects combine with the arrival of a possible weak CME glancing blow from the events on 8 and 10 Nov. Mostly quiet conditions are expected on day three (14 Nov). All three days are expected to remain below G1 (Minor) levels.
Posted on: Tue, 12 Nov 2013 12:56:39 +0000
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