####018001226#### AXXX82 KWNP 300031 DAYOBS :Product: Summary of Space Weather Observations dayobs.txt :Issued: 2025 Sep 30 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 29 # Region Location Sunspot Characteristics # Helio Spot Spot Mag. # Num Lat.,CMD Long. Area Extent class count class 4225 N08W91 175 120 3 HSX 1 A 4226 S11W48 133 70 3 HSX 3 A 4227 S17W56 140 10 5 BXO 3 B 4230 S11W23 108 100 8 DAO 16 BG 4232 N05E35 49 250 5 DHO 3 BG 4233 N17E34 50 60 8 DAO 8 B 4235 N28E38 47 25 3 CAO 3 B 4236 N11E27 57 80 7 DAI 12 BG 4237 N16W05 89 10 4 BXO 3 B 4238 S13W26 111 10 5 BXO 6 B 4239 S09W27 112 45 3 HAX 2 A ####018004741#### FXXX12 KWNP 300031 DAYDIS :Product: Forecast Discussion :Issued: 2025 Sep 30 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 moderate due to multiple M-class (R1-Minor) flares from various regions. Region 4232 (N05E35, Dho/beta-gamma) was responsible for the largest flare of the period - an M3.7 at 29/0145 UTC. The regions leader decayed slightly with its trailer becoming more symmetric; activity will likely decrease as the region becomes more stable. The cluster of spots around former Region 4230 (S11W23, Dao/beta-gamma) has now been broken up into three distinct regions - Region 4230 remains in the NE of that cluster which showed growth in both its leader and trailer with increased spot count. Region 4238 (S13W26, Bxo/beta) was created to its south which exhibited slight growth and then Region 4239 (S09W27, Hax/alpha) to its west which has been stable throughout the period. Region 4233 (N17E34, Dao/beta) has been active but is relatively simple, with rudimentary penumbra in both its leader and trailer. Region 4236 (N11E27, Dai/beta-gamma) produced numerous C-class flares along with an M-class. Rapid flux emergence over the last 24 hours has produced a ring shaped structure increasing its probability for continued flaring. A diffuse CME off the SE part of the disk was observed in coronagraph imagery around 29/0224 UTC. There is a slight chance for a disturbance to occur from the tail end of the CME on 01 Oct but confidence is very low. .Forecast... With multiple regions continuing to exhibit growth, flare activity is expected to remain at moderate levels (R1-R2/Minor-Moderate) with a slight chance for an X-class flare (R3-Strong) through 02 Oct. Energetic Particle .24 hr Summary... As the coronal hole (CH) high speed stream (HSS) influence wanes, the greater than 2 MeV electron flux has returned to mostly moderate (100 pfu) conditions. The greater than 10 MeV proton flux remained at background levels. .Forecast... The greater than 2 MeV electron flux is expected to remain at moderate levels through 02 Oct. There is a nonzero chance that Region 4230 could produce a significant flare, and with its position in the SW part of the disk an S1 (Minor) proton event is possible, but chances are extremely low. The greater than 10 MeV proton flux will most likely remain at background levels through 02 Oct. Solar Wind .24 hr Summary... Solar wind parameters were elevated due to an unknown source. An exiting, negative polarity CH HSS may have influenced the magnitude of the interplanetary magnetic field (IMF) but its strength coupled with the lower wind speed is not in alignment with this being the only player. The total field (Bt) reached a maximum of 14.8 nT with the north-south (Bz) component dipping as far south as -13 nT. Solar wind speeds oscillated around 400 km/s, which are getting close towards nominal...The interesting parameter was the phi angle - it remained negative (towards the Sun) which is to be expected given the HSS connection in previous days. But around 29/1200 UTC the angle trended from 266-360 degrees before flipping to the positive sector. Its possible there was a negative Bz magnetic field embedded within an overturning heliospheric current sheet. Once the sheet turned positive, Bz turned north. .Forecast... Solar wind parameters, specifically the IMF, are likely to continue on the downward trend towards nominal levels. With no CH HSS becoming geoeffective within the next three days, wind speeds are likely to trend towards 350-400 km/s. A weak CME discussed previously may disrupt solar wind parameters around 01 Oct, but confidence is low. Geospace .24 hr Summary... The geomagnetic field reached G1 (Minor) geomagnetic storming levels during three synoptic periods - between 09-12, 15-18, and 18-21 UTC. This is due to the sustained southward Bz component as discussed earlier in the Solar Wind section. Unless conditions degrade, the current Kp=5 Warning is expected to expire at 30/00 UTC without extension. .Forecast... Active to unsettled conditions are expected through 02 Oct. There is a slight chance for an enhancement of the field on 01 Oct due to a weak CME that left the disk 29/0224 UTC but confidence is low on its arrival. If it does arrive, impacts will be minimal as the CME was very diffuse. -Bri ####018002279#### FXXX10 KWNP 300031 DAYTDF :Product: 3-Day Forecast :Issued: 2025 Sep 30 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 5 (NOAA Scale G1). The greatest expected 3 hr Kp for Sep 30-Oct 02 2025 is 4.00 (below NOAA Scale levels). NOAA Kp index breakdown Sep 30-Oct 02 2025 Sep 30 Oct 01 Oct 02 00-03UT 4.00 2.67 1.33 03-06UT 3.67 2.00 1.33 06-09UT 3.67 2.00 1.33 09-12UT 3.00 3.00 1.67 12-15UT 2.67 2.67 1.33 15-18UT 2.33 2.67 1.33 18-21UT 2.33 2.67 1.67 21-00UT 2.67 3.00 1.67 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 30-Oct 02 2025 Sep 30 Oct 01 Oct 02 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 29 2025 0145 UTC. Radio Blackout Forecast for Sep 30-Oct 02 2025 Sep 30 Oct 01 Oct 02 R1-R2 55% 55% 55% R3 or greater 10% 10% 10% Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely, with a slight chance for R3 (Strong), over 30 Sep - 02 Oct due to the flare potential from multiple complex regions on the solar disk.