####018002701#### FXXX12 KWNP 251231 DAYDIS :Product: Forecast Discussion :Issued: 2024 Apr 25 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 with four R1 (Minor) events observed. Region 3638 (S18, L=229) produced an M2.0 flare at 24/2259 UTC, the strongest flare of the period, before decaying to plage. Regions 3648 (N18W53, Dai/beta-gamma) and 3654 (S08E13, Eai/beta-gamma) grew in size, spot count, and complexity this period. Overall decay was noted within the active region cluster in the SW. New Region 3659 (S13E41, Axx/alpha) was numbered this period, but was otherwise unremarkable. No Earth-directed CMEs were detected in available coronagraph imagery. .Forecast... Solar activity is expected to be at moderate levels over 25-27 Apr, with M-class flares (R1-R2/Minor-Moderate) expected, and a slight chance for an X-class flare (R3/Strong). Energetic Particle .24 hr Summary... The greater than 2 MeV electron flux reached high levels this period while the greater than 10 MeV proton flux was at background levels. .Forecast... There is a slight chance for the greater than 10 MeV proton flux to reach S1 (Minor) levels over 25-27 Apr due to the flare potential and location of several active regions on the visible disk. The greater than 2 MeV electron flux is expected to reach high levels on 25-27 Apr. Solar Wind .24 hr Summary... Solar wind conditions reflected nominal conditions. Total magnetic field strength was at or below 5 nT and the Bz component was mostly northward through the period. Solar wind speeds decreased from around 375 km/s early in the period to end-of-period values near 325 km/s. The phi angle was variable. .Forecast... Enhanced solar wind conditions are likely over 25-27 Apr due to CH HSS influences and possible transient activity associated with multiple CMEs that are expected to pass in close proximity over the next few days. Geospace .24 hr Summary... The geomagnetic field was quiet. .Forecast... Geomagnetic field activity is expected to range from quiet to active levels on 25-27 Apr due to the anticipated influence of CH HSSs combined with potential transient influence of multiple near-miss CMEs from the past several days. A chance for minor (G1) geomagnetic storm periods exists over 25-26 Apr should these features arrive at Earth and carry periods of significant southward Bz. ####018002195#### FXXX10 KWNP 251231 DAYTDF :Product: 3-Day Forecast :Issued: 2024 Apr 25 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 1 (below NOAA Scale levels). The greatest expected 3 hr Kp for Apr 25-Apr 27 2024 is 4.00 (below NOAA Scale levels). NOAA Kp index breakdown Apr 25-Apr 27 2024 Apr 25 Apr 26 Apr 27 00-03UT 0.67 3.67 2.67 03-06UT 0.33 4.00 3.67 06-09UT 0.00 3.33 3.00 09-12UT 1.33 3.00 2.67 12-15UT 3.00 2.67 2.67 15-18UT 3.00 2.00 2.67 18-21UT 3.33 2.00 3.00 21-00UT 4.00 2.67 3.33 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 Apr 25-Apr 27 2024 Apr 25 Apr 26 Apr 27 S1 or greater 15% 15% 15% Rationale: There is a slight chance for S1 (Minor) storms over 25-27 Apr due to the position and flare potential of several active regions on the disk. C. NOAA Radio Blackout Activity and Forecast Radio blackouts reaching the R1 levels were observed over the past 24 hours. The largest was at Apr 24 2024 2259 UTC. Radio Blackout Forecast for Apr 25-Apr 27 2024 Apr 25 Apr 26 Apr 27 R1-R2 75% 75% 75% R3 or greater 15% 15% 15% Rationale: R1-R2 (Minor-Moderate) events are expected, with a slight chance for an R3 (Strong) event, over 25-27 Apr.