####018001052#### AXXX82 KWNP 120031 DAYOBS :Product: Summary of Space Weather Observations dayobs.txt :Issued: 2025 Dec 12 0030 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 # # Summary of Space Weather Observations # :Solar_Region_Summary: 2025 Dec 11 # Region Location Sunspot Characteristics # Helio Spot Spot Mag. # Num Lat.,CMD Long. Area Extent class count class 4294 S15W81 284 780 14 EKC 15 BGD 4296 S15W69 272 420 12 EKO 6 BG 4298 S16W0* 306 60 3 CSO 2 B 4299 N22W64 266 10 4 BXO 4 B 4304 N26W49 252 110 7 CAI 6 BG 4305 S25E06 196 140 8 DAO 8 B 4306 S16W28 231 10 4 BXO 5 B 4307 S11E08 195 30 4 DRO 9 B ####018002125#### FXXX10 KWNP 120031 DAYTDF :Product: 3-Day Forecast :Issued: 2025 Dec 12 0030 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 Dec 12-Dec 14 2025 is 4.67 (NOAA Scale G1). NOAA Kp index breakdown Dec 12-Dec 14 2025 Dec 12 Dec 13 Dec 14 00-03UT 4.00 4.33 3.67 03-06UT 4.67 (G1) 3.67 3.00 06-09UT 4.00 2.33 2.67 09-12UT 3.67 1.67 2.67 12-15UT 3.33 2.00 2.67 15-18UT 3.00 2.67 2.00 18-21UT 3.33 3.33 2.00 21-00UT 3.67 3.67 2.67 Rationale: G1 (Minor) storming is likely early on 12 Dec as weak enhancements in the solar wind environment persist. 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 Dec 12-Dec 14 2025 Dec 12 Dec 13 Dec 14 S1 or greater 10% 5% 1% Rationale: There is a slight chance for an S1 (Minor) radiation storming event on 12 Dec as the complex regions in the western hemisphere move beyond the limb. C. NOAA Radio Blackout Activity and Forecast No radio blackouts were observed over the past 24 hours. Radio Blackout Forecast for Dec 12-Dec 14 2025 Dec 12 Dec 13 Dec 14 R1-R2 65% 60% 55% R3 or greater 10% 5% 5% Rationale: Chances for R1-R2 (Minor-Moderate) radio blackouts decrease over 12-14 Dec as major flare producing regions move beyond the west limb. ####018003401#### FXXX12 KWNP 120031 DAYDIS :Product: Forecast Discussion :Issued: 2025 Dec 12 0030 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 low levels with only C-class level flares observed throughout the period. Region 4294 (S15W81, Ekc/beta-gamma-delta) was the primary producer with the largest flare being a C9.7 at 11/1546 UTC. The region is moving beyond the west limb now and is becoming too difficult to characterize due to foreshortening. All other regions were stable or in decay. There were no Earth-directed CMEs in coronagraph imagery. .Forecast... Probabilities for flare activity decrease through 14 Dec as major flare producing regions move beyond the west limb. Chances for R1-R2 (Minor-Moderate) flares decrease from 75% to 55%, and chances for R3 (Strong) decrease from 10% to 5% over the three days. Energetic Particle .24 hr Summary... The greater than 2 MeV electron flux remained at moderate levels throughout the period. The greater than 10 MeV proton flux remained at background. .Forecast... Electrons are expected to become elevated through 14 Dec as coronal hole (CH) high speed stream (HSS) originating from the negative polarity CH in the northern hemisphere becomes geoeffective. Electrons will likely surpass the 1,000 pfu threshold during the diurnal maxima. As complex regions in the western hemisphere move beyond the limb, chances for protons to become elevated decrease. There is a 10% chance for an S1 (Minor) radiation storming event on 12 Dec, with chances decreasing to 1% by 14 Dec. Solar Wind .24 hr Summary... Solar wind parameters remained elevated due to what is assumed to be multiple transients and undulations between current sheets. The total field decreased from near 22 nT towards 10 nT. The north-south Bz component remained between +/-16 nT. Solar wind speeds remained between 400-450 km/s. The phi angle was predominantly positive until roughly 11/1300 UTC when rotation into the negative sector occurred. .Forecast... Solar wind is expected to remain slightly elevated early on 12 Dec before trending towards nominal levels by midday. Additional enhancements are likely again late on 12 Dec with the arrival of an incoming co-rotating interacting region associated with a negative polarity CH HSS. Wind speeds with the HSS are expected to rise towards 650 km/s 13-14 Dec. Geospace .24 hr Summary... Due to an enhancement early in the period that sustained a perturbed solar wind environment along with a sector boundary crossing late in the period, the geomagnetic field reached G1-G2 (Minor-Moderate) storming levels. .Forecast... The geomagnetic field is expected to be at unsettled to active levels, with G1 (Minor) storming likely, early on 12 Dec as weak enhancements in the solar wind environment persist. Following a brief respite the latter half of 12 Dec, additional enhancements are likely by the end of 12 Dec through early 13 Dec with the arrival of a CIR/HSS. Unsettled to active levels are likely to continue into 14 Dec as CH HSS influence lingers.