####018001226#### AXXX82 KWNP 260031 DAYOBS :Product: Summary of Space Weather Observations dayobs.txt :Issued: 2025 Sep 26 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 Sep 25 # Region Location Sunspot Characteristics # Helio Spot Spot Mag. # Num Lat.,CMD Long. Area Extent class count class 4217 S17W75 213 150 3 CAO 8 B 4220 S17W0* 247 150 11 ESO 5 B 4221 N04W83 221 100 1 HSX 1 A 4224 S13W68 206 10 3 CSO 4 B 4225 N10W40 178 150 3 HSX 3 A 4226 S11E06 132 220 7 DAO 13 B 4227 S19E01 137 80 5 HAX 5 A 4228 N04E13 125 40 2 HSX 1 A 4229 S04W61 199 70 4 DSO 8 B 4230 S11E30 108 100 11 ESO 4 B 4231 S07W50 188 10 3 CSO 2 B ####018002524#### FXXX12 KWNP 260031 DAYDIS :Product: Forecast Discussion :Issued: 2025 Sep 26 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 returned to low levels, with several C-class flares observed. Regions 4217 (S17W75, Cao/beta) and 4224 (S13W68, Cso/beta) were the most active regions, producing a few low-level C-class flares each. Region 4224 contributed the largest of the period, a C3.6 at 25/0409 UTC. Region 4226 (S11E06, Dao/beta) added a few flares as well. Region 4224 gained several intermediate and trailer spots. Region 4229 (S04W61, Dso/beta) grew slightly, but lost its beta-gamma configuration. New Region 4231 (S07W50,Cso/beta) developed and was numbered during the period, but was inactive. The remaining regions were stable or in decay. No Earth-directed CMEs observed in available coronagraph imagery. .Forecast... Solar activity is expected to be low, with a chance for isolated M-class flare activity (R1-R2/Minor-Moderate) through 28 Sep. Energetic Particle .24 hr Summary... The greater than 2 MeV electron flux remained at moderate levels. The greater than 10 MeV proton flux was at background. .Forecast... The greater than 2 MeV electron flux is expected to continue at moderate levels, with a chance for high levels, on 26-28 Sep as CH HSS influences wane. The greater than 10 MeV proton flux is expected to continue at background levels all three days. Solar Wind .24 hr Summary... Negative polarity CH HSS effects continued to weaken slightly through the period. Total field averaged around 5 nT, Bz fluctuated between +/-5 nT, and solar wind speeds continued a gradual decline from 550 to 460 km/s. The phi angle was negative. .Forecast... Mostly nominal conditions are expected through 26 Sep. Relatively weak enhancements are anticipated by late on 27 Sep, lasting into 28 Sep, as negative polarity CH HSS influences begin. Geospace .24 hr Summary... The geomagnetic field was at quiet to unsettled levels. .Forecast... Mostly quiet levels are expected through 26 Sep as CH influences diminish. Quiet to unsettled conditions are expected on 27 Sep, with active levels likely on 28 Sep, as a subsequent negative polarity CH HSS moves into position. ####018002158#### FXXX10 KWNP 260031 DAYTDF :Product: 3-Day Forecast :Issued: 2025 Sep 26 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 3 (below NOAA Scale levels). The greatest expected 3 hr Kp for Sep 26-Sep 28 2025 is 3.67 (below NOAA Scale levels). NOAA Kp index breakdown Sep 26-Sep 28 2025 Sep 26 Sep 27 Sep 28 00-03UT 1.67 2.33 2.33 03-06UT 1.33 2.00 2.00 06-09UT 1.33 2.00 2.00 09-12UT 1.33 1.67 2.00 12-15UT 1.33 2.00 2.00 15-18UT 1.33 2.00 3.00 18-21UT 1.67 2.00 3.33 21-00UT 1.67 3.00 3.67 Rationale: No G1 (Minor) or greater geomagnetic storms are expected. No significant transient or recurrent solar wind features are forecast. 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 Sep 26-Sep 28 2025 Sep 26 Sep 27 Sep 28 S1 or greater 1% 1% 1% 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 No radio blackouts were observed over the past 24 hours. Radio Blackout Forecast for Sep 26-Sep 28 2025 Sep 26 Sep 27 Sep 28 R1-R2 30% 30% 30% R3 or greater 5% 5% 5% Rationale: A chance for R1-2 (Minor-Moderate) radio blackouts due to isolated M-class flare acitivity will persist through 28 Sep.