####018004038#### FXXX12 KWNP 111231 DAYDIS :Product: Forecast Discussion :Issued: 2025 Nov 11 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 reached high levels (R3-Strong) again this period, due to another X-class flare from Region 4274 (N24W28, Fkc/beta-gamma-delta). The impulsive X5.1/3B flare (R3-Strong) peaked at 11/1004 UTC. This event had an associated Type-II (1350 km/s) radio sweep and an F10.7 cm radio burst (10,000 sfu). There was also a Castelli-U radio burst, as well as another asymmetric halo CME with the bulk of the ejecta again having a NW bias. Modelling of the event is currently underway. Region 4274 continued to exhibit minor growth over the period, with little change to its enhanced magnetic complexity. This Region was responsible for nearly all of the flare activity during the period. Only Region 4279 (S12E35, Hsx/alpha) contributed to the flare count, adding a C2.9/Sf flare at 11/0255 UTC. The remainder of the spotted regions were either stable or in decay and remained inactive. New Region 4280 (S09E54, Bxo/beta) was numbered. .Forecast... Solar activity is expected to be moderate (R1-R2, Minor-Moderate) with a chance for further X-class (R3-Strong) activity on 11-13 Nov due to the flare potential of Region 4274. Energetic Particle .24 hr Summary... The greater than 2 MeV electron flux reached high levels with a peak flux of 10,104 pfu observed at 10/1535 UTC. The greater than 10 MeV proton flux began to increase after 10/1000 UTC following the X1.2 flare at 10/0919 UTC. S1 (Minor) levels were reached at 10/1125 UTC. Following the X5.1/3B flare at 11/1004 UTC, flux levels began to increase further, with a peak flux of 59.3 pfu as of the writing of this summary. Additionally, the 100 MeV proton flux levels exceeded the 1 pfu threshold at 11/1029 UTC, reaching a peak of 14.4 pfu as of this summary. Although both the 10 MeV and 100 MeV flux levels appear to be slowing their ascent, they continue to slowly increase as of this writing. .Forecast... The greater than 2 MeV electron flux is expected to reach high levels on 11 Nov followed by a decrease to moderate levels on 12-13 Nov with the arrivals of the 09-10 CMEs. The greater than 10 MeV proton flux is expected to continue above the S1 (Minor) threshold through 12 Nov, with S2 levels possible through 11 Nov. Levels should begin to decrease later on 11 Nov but remain above S1 levels through 12 Nov. Further enhancements are possible with the arrival of the 09-10 CMEs on 11 and 12 Nov. Solar Wind .24 hr Summary... Solar wind parameters returned to near-ambient levels. Solar wind speed decreased from just under 600 km/s to end the period near 450 km/s. Total field varied from 1-8 nT at the beginning of the period before settling in to average near 6 nT the latter half of the period. The Bz component was mostly southward after ~10/1800 UTC before slowly gradually drifting northward by the end of the period. Phi angle was predominantly negative. .Forecast... The solar wind environment is expected to become enhanced on 11-13 Nov with the arrival of two CMEs. The 09 Nov CME is expected to arrive late on 11 Nov followed by the 10 Nov CME early on 12 Nov (UTC day). Solar wind speeds exceeding 700 km/s are likely following the arrival. Geospace .24 hr Summary... The geomagnetic field was at quiet to unsettled levels, with an isolated active period. .Forecast... G1-G2 (Minor-Moderate) levels are likely by late on 11 Nov with the arrival of the 09 Nov CME. G1-G3 (Minor-Strong) levels are likely on 12 Nov with the arrival of the 10 Nov CME. Unsettled to G1 (Minor) storming is likely on 13 Nov as conditions slowly diminish. ####018002561#### FXXX10 KWNP 111231 DAYTDF :Product: 3-Day Forecast :Issued: 2025 Nov 11 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 4 (below NOAA Scale levels). The greatest expected 3 hr Kp for Nov 11-Nov 13 2025 is 7.33 (NOAA Scale G3). NOAA Kp index breakdown Nov 11-Nov 13 2025 Nov 11 Nov 12 Nov 13 00-03UT 2.33 5.00 (G1) 4.33 03-06UT 2.67 7.33 (G3) 4.67 (G1) 06-09UT 1.67 6.00 (G2) 4.00 09-12UT 2.33 4.67 (G1) 3.67 12-15UT 4.67 (G1) 4.33 3.33 15-18UT 5.00 (G1) 3.33 2.67 18-21UT 5.67 (G2) 3.33 2.67 21-00UT 5.67 (G2) 4.00 3.00 Rationale: G1-G2 (Minor-Moderate) levels are likely by late on 11 Nov with the arrival of the 09 Nov CME. G1-G3 (Minor-Strong) levels are likely on 12 Nov with the arrival of the 10 Nov CME. Unsettled to G1 (Minor) storming is likely on 13 Nov as conditions slowly diminish. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was above S-scale storm level thresholds. Solar Radiation Storm Forecast for Nov 11-Nov 13 2025 Nov 11 Nov 12 Nov 13 S1 or greater 99% 75% 65% Rationale: The greater than 10 MeV proton flux is expected to continue above the S1 (Minor) threshold through 12 Nov, with S2 levels possible through 11 Nov. Levels should begin to decrease later on 11 Nov but remain above S1 levels through 12 Nov. Further enhancements are possible with the arrival of the 09-10 CMEs on 11 and 12 Nov. C. NOAA Radio Blackout Activity and Forecast Radio blackouts reaching the R3 levels were observed over the past 24 hours. The largest was at Nov 11 2025 1004 UTC. Radio Blackout Forecast for Nov 11-Nov 13 2025 Nov 11 Nov 12 Nov 13 R1-R2 75% 75% 75% R3 or greater 35% 35% 35% Rationale: R1-R2 (Minor-Moderate) radio blackouts are expected, with a chance for further R3 (Strong) activity on 11-13 Nov due to the flare potential of Region 4274.