:Product: Weekly Highlights and Forecasts :Issued: 2024 Oct 28 0319 UTC # Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center # Product description and SWPC contact on the Web # https://www.swpc.noaa.gov/content/subscription-services # # Weekly Highlights and Forecasts # Highlights of Solar and Geomagnetic Activity 21 - 27 October 2024 Solar activity ranged from low to high. High levels were reached on 24 Oct, with the largest event of the reporting period, an X3.3 (R3-Strong) at 24/0357 UTC from Region 3869 (S17, L=195, class/area = Eki/460 on 24 Oct). Associated with this event were Type II and Type IV radio sweeps, a 10cm flare, and a partial halo CME. High levels were again reached on 26 Oct due to an X1.8 (R3) at 26/0719, from Region 3873 (S10, L=176, class/area = Dai/240 on 24 Oct), also with associated Type II, Type IV, 10cm flare, and partial halo CME. The associated CME was first observed in SOHO/LASCO C2 imagery at 26/0636. The event was modeled and analyzed, with output suggests potential arrival at Earth early on 28 Oct. Solar activity was moderate on 25 Oct, with a M1.1 (R1-Minor) at 25/0733 UTC, also from Region 3873, and on 27 Oct, with a M2.8 (R1) at 27/2324 UTC from Region 3878 (N18, L=141, class/area = Dso/80 on 27 Oct). The remainder of the summary period was at low levels. Other activity included Region 3878 which rotated onto the visible disk on 27 Oct, but there were three M-flares on 26 Oct that appeared to occur in the vicinity of the region behind the limb. There is a large complex of sunspot regions in the south-east quadrant, including Regions 3869--3876, with flux emergence muddling the boundaries between individual regions. The greater than 10 MeV protons flux increased above background level following R3 flare activity on 24 Oct. The S1 (Minor) threshold was reached on 26 Oct at 1910 UTC following another R3 event from Region 3873. They further increased to S2 (Moderate) threshold at 27/0850 UTC. Flux remained elevated above the S2 threshold for the remainder of the reporting period. The greater than 2 MeV electron flux at geosynchronous orbit was at normal background to moderate levels throughout the reporting period. Geomagnetic field activity ranged from quiet to active conditions. Active periods were observed on 24 Oct, due to influence from a positive CH with a possibly embedded transient, and on 26 Oct, due to influence from the CME associated with the X3.3 flare from Region 3869 on Oct 24. On 26 Oct, Bz was primarily northward but the total magnetic field reached 26 nT with wind speeds around 450-500 km/s. The remainder of the reporting period was at quiet to unsettled levels. Forecast of Solar and Geomagnetic Activity 28 October - 23 November 2024 Solar activity is expected to be at moderate levels (R1/R2-Minor/Moderate), with the chance of high levels (R3-Strong), from 28 Oct to 6 Nov, as the southern complex of active regions rotates westward. The remainder of the outlook period is likely to reach moderate levels. The greater than 10 MeV protons are expected to remain elevated at S2 through 28 Oct and S1 on 29 Oct, with the chance of additional events following activity from the southern spot complex as it rotates off the disk. No other proton events are expected at geosynchronous orbit in the remainder of the outlook period. The greater than 2 MeV electron flux at geosynchronous orbit is expected to be background to high levels due to potential passage of the CME associated with the X1.8 (R3) on 26 Oct. Geomagnetic field activity is likely to reach G2 (Moderate) storm levels on 28 Oct and G1 (Minor) storm levels on 29 Oct due to anticipated influence of a CME that left the Sun on 26 Oct. Active levels are likely on 11-12 Nov, 15 Nov, and 20 Nov due to influence from recurrent CH HSSs, with Unsettled levels on 13 Nov, 16 Nov, and 18 Nov as the influences wane. The remainder of the outlook period is expected to be at mostly quiet levels.