Solar activity reached moderate levels on October 13 after Active Region 4246, positioned at N22W30, produced a sequence of M-class solar flares. The region expanded significantly, developing a beta-gamma-delta magnetic configuration with multiple new sunspots forming during the day.
Three moderate flares were detected — an M1.9 at 05:26 UTC, an M2.7 at 09:19 UTC, and an M1.2 at 13:18 UTC. CMEs accompanied the M1.9 and M1.2 flares, with the latter associated with a 570 km/s Type II Radio emission.
Modeling indicates an Earth arrival window around mid to late October 17, but SWPC noted that previous CMEs from the same region are expected to arrive between October 15 and 16. This may lead to an earlier-than-modeled arrival for the October 13 eruptions as the solar wind environment becomes preconditioned by earlier ejecta. Updated modeling efforts are underway to refine the forecast.
“Not only do we have 4 solar storms on the way to Earth, but a gorgeous East limb eruption keeps us distracted while Region 4246 fires off yet another big eruption,” said space weather physicist Dr. Tamitha Skov. “Check out the huge tower of plasma at the end of this video jetting from Region 4246 just moments ago!”
Other active regions present on the disk exhibited limited changes over the past 24 hours. AR4248 (N07E01) showed minor decay across its intermediate section, while AR4247 (S12W64) and AR4250 (N07E06) continued to weaken.
SWPC forecasts high probability of R1 – Minor to R2 – Moderate radio blackouts, with a slight chance of R3 – Strong through October 16 due to the continuing flare potential of AR4246.
The greater than 2 MeV electron flux reached high levels on October 13, peaking at 4 080 pfu at 14:25 UTC, while the greater than 10 MeV proton flux remained at background levels. High electron flux conditions are forecast to persist through October 14 before declining to normal–moderate levels by October 15–16. There is a slight chance for S1 – Minor proton event through October 16.
Solar wind parameters continue to show the influence of a negative polarity coronal hole high-speed stream. The total magnetic field (Bt) decreased from 6–7 nT to 4–5 nT, while the Bz component fluctuated between ±6 nT, remaining mostly neutral or northward. Average solar wind speeds were just below 700 km/s over the past 24 hours.
The geomagnetic field reached G1 – Minor levels early on October 13 and was mostly unsettled to active thereafter.
Enhanced solar wind conditions are expected to persist through October 14, gradually waning before the next CME arrivals late on October 15–16. The impacts are forecast to cause active to G1 geomagnetic storm conditions.
SWPC forecasts active levels on October 14, quieter intervals into October 15, and renewed disturbances late October 15 through October 16 as multiple CME fronts interact with Earth’s magnetosphere, causing minor storming.
High-latitude regions could experience enhanced auroral activity and occasional shortwave communication disturbances as a result.
