####018003292#### FXXX12 KWNP 011231 DAYDIS :Product: Forecast Discussion :Issued: 2025 Oct 01 1230 UTC # Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center # Product description and SWPC contact on the Web # http://www.swpc.noaa.gov/wwire.html # # Forecast Discussion # Solar Activity .24 hr Summary... Solar activity was at moderate levels due to M-flare activity associated with the Region 4232 (N04E08, Dhi/beta-gamma), that produced an M1.2/1N flare peaking at 01/0226 UTC while maintaining a stable size and magnetic complexity during the period. The most complex regions on the solar disk are currently Region 4230 (S10W51, Eki/beta-gamma-delta) and 4236 (N10W00, Dki/beta-gamma-delta). Both showed area increases and produced C-class flares. It is important to note that, after careful assessment of recent magnetograph imagery, a spot previously associated to region 4239 (S10W55, decayed) is now considered part of the 4230, explaining its reported size increase. A new region appeared around N14W44, but remained unnumbered until further observation. Field line movement was observed in GOES-19 SUVI 284 imagery beginning at approximately 01/1012 UTC, suggesting a CME. Although, an Earth-directed component to this event is unlikely proper analysis will be conducted once adequate coronagraph imagery becomes available. .Forecast... With multiple regions continuing to exhibit growth, flare activity is likely to remain at moderate levels (R1-R2/Minor-Moderate) with a slight chance for an X-class flare (R3-Strong) through 03 Oct. Energetic Particle .24 hr Summary... The greater than 2 MeV electron flux at geostationary orbit was at nominal to moderate levels, while the the greater than 10 MeV proton fluxes measured by GOES-R satellites remained at background levels. .Forecast... A chance for high levels of greater than 2 MeV electrons is considered through 02 Oct due to magnetospheric response to ongoing influence of a corotating interacting region (CIR) associated to a positive polarity coronal hole (CH) high speed stream (HSS). The greater than 10 MeV proton flux is expected to remain at background levels. Solar Wind .24 hr Summary... The solar wind environment was under the influence of a positive CH HSS with speeds reaching 800 km/s. Total Interplanetary Magnetic Field (IMF) decreased from 19nT to 7nT and the north-south Bz component of the IMF underwent several southward deflections of -9 to -11nT. Phi was predominantly positive with a few brief excursions into the negative solar sector. .Forecast... CH HSS influences are expected to persist for the remainder 01 Oct and days ahead. It is important to highlight that the coupling between a HSS associated with positive polarity CH and the Earths magnetosphere is expected to be maximized around the Sep equinox, which is ongoing. Geospace .24 hr Summary... Geomagnetic activity was primarily at G1 (Minor) to G2 (Moderate) storm levels. .Forecast... G2 (Moderate) levels are likely for the remainder 01 Oct. Unsettled to active conditions are expected on 02-03 Oct and as positive polarity CH HSS influences persist. ####018002123#### FXXX10 KWNP 011231 DAYTDF :Product: 3-Day Forecast :Issued: 2025 Oct 01 1230 UTC # Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center # Product description and SWPC contact on the Web # http://www.swpc.noaa.gov/wwire.html # # 3-Day Forecast # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 6 (NOAA Scale G2). The greatest expected 3 hr Kp for Oct 01-Oct 03 2025 is 5.67 (NOAA Scale G2). NOAA Kp index breakdown Oct 01-Oct 03 2025 Oct 01 Oct 02 Oct 03 00-03UT 5.33 (G1) 3.33 3.00 03-06UT 5.33 (G1) 3.00 3.00 06-09UT 4.67 (G1) 3.00 2.67 09-12UT 3.67 3.67 3.00 12-15UT 4.67 (G1) 3.00 3.00 15-18UT 3.67 3.00 3.67 18-21UT 4.00 3.33 3.00 21-00UT 5.67 (G2) 3.67 2.00 Rationale: G2 (Moderate) geomagnetic storms are likely due to CH HSS influences. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Oct 01-Oct 03 2025 Oct 01 Oct 02 Oct 03 S1 or greater 5% 5% 5% Rationale: No S1 (Minor) or greater solar radiation storms are expected. No significant active region activity favorable for radiation storm production is forecast. C. NOAA Radio Blackout Activity and Forecast Radio blackouts reaching the R1 levels were observed over the past 24 hours. The largest was at Sep 30 2025 1230 UTC. Radio Blackout Forecast for Oct 01-Oct 03 2025 Oct 01 Oct 02 Oct 03 R1-R2 60% 60% 60% R3 or greater 15% 15% 15% Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely with slight chances for isolated R3 stronger events.