####018002814#### FXXX12 KWNP 151231 DAYDIS :Product: Forecast Discussion :Issued: 2024 Apr 15 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 moderate levels due to (R1-Minor) solar activity from Regions 3639 (N30E55, Dsi/beta) and 3634 (N25W35, Ehi/beta). Region 3639 produced an impulsive M1.7/Sf at 15/0118 UTC, an M1.0/Sf at 15/0732 UTC and an impulsive M1.2/Sf at 15/0932 UTC, along with numerous C-class flares. Region 3634 produced an impulsive M2.3/1b at 15/0842 UTC. Region 3639 grew in sunspot count and area. Slight growth and consolidation was observed in Regions 3634 and 3641 (N11E06, Dao/beta). New Regions 3642 (N18W04, Cao/beta) and 3643 (S10E70, Dao/beta) were numbered this period. A faint CME was observed off the NE limb at 14/1124 UTC in SOHO/LASCO C2 imagery related to a C5.0/Sf flare at 14/1101 UTC from Region 3636 (S21E27, Cso/beta). Analysis of this event suggests a component will interact with Earth late on 17 through 18 Apr. .Forecast... Solar activity is expected to be low with a chance for M-class flares (R1-R2/Minor-Moderate) on 15-17 Apr. Energetic Particles .24 hr Summary... The greater than 10 MeV proton flux was at background levels. The greater than 2 MeV electron flux was at normal to moderate levels. .Forecast... The greater than 10 MeV proton flux is expected to remain at background levels. The greater than 2 MeV electron flux is expected to continue at normal to moderate levels through 17 Apr. Solar Wind .24 hr Summary... Solar wind parameters remained at nominal levels. Total field ranged from 2-5 nT while the Bz component was between +/-4 nT. Solar wind speed weakly varied between 350-400 km/s. Solar sector was in a predominately negative solar sector. .Forecast... Solar wind conditions are expected to become enhanced on 15 Apr due to the anticipated arrival of the 12 Apr CME, in addition to CH HSS influences. Solar wind parameters are expected to recover to nominal levels on 16 Apr. By mid to late on 17 Apr, solar wind conditions are expected to become enhanced due to the anticipated arrival of the 14 Apr CME. Geospace .24 hr Summary... The geomagnetic field was at quiet levels. .Forecast... Unsettled to active levels are expected, with periods of G1 (Minor) storming likely, on 15 Apr due to the passage of a CME from 12 Apr combined with CH HSS influences. Quiet to unsettled levels are expected on 16 Apr increasing to unsettled to active conditions on 17 Apr due to CME effects. ####018002160#### FXXX10 KWNP 151231 DAYTDF :Product: 3-Day Forecast :Issued: 2024 Apr 15 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 2 (below NOAA Scale levels). The greatest expected 3 hr Kp for Apr 15-Apr 17 2024 is 4.00 (below NOAA Scale levels). NOAA Kp index breakdown Apr 15-Apr 17 2024 Apr 15 Apr 16 Apr 17 00-03UT 2.33 3.00 1.67 03-06UT 2.00 3.00 2.00 06-09UT 0.67 2.33 2.33 09-12UT 1.67 2.00 2.67 12-15UT 2.33 1.33 3.33 15-18UT 2.00 1.00 3.33 18-21UT 2.33 1.33 3.67 21-00UT 2.67 2.00 4.00 Rationale: Isolated periods of G1 (Minor) geomagnetic storms are likely on 15 Apr due to CME effects and CH HSS influences. 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 15-Apr 17 2024 Apr 15 Apr 16 Apr 17 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 Radio blackouts reaching the R1 levels were observed over the past 24 hours. The largest was at Apr 15 2024 0842 UTC. Radio Blackout Forecast for Apr 15-Apr 17 2024 Apr 15 Apr 16 Apr 17 R1-R2 45% 45% 45% R3 or greater 5% 5% 5% Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts over 15-17 Apr.