####018002159#### FXXX10 KWNP 131231 DAYTDF :Product: 3-Day Forecast :Issued: 2024 Apr 13 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 13-Apr 15 2024 is 4.67 (NOAA Scale G1). NOAA Kp index breakdown Apr 13-Apr 15 2024 Apr 13 Apr 14 Apr 15 00-03UT 2.00 1.67 4.00 03-06UT 2.33 1.67 3.67 06-09UT 0.67 4.00 3.33 09-12UT 1.00 3.00 3.00 12-15UT 2.00 3.00 3.00 15-18UT 2.33 4.00 2.33 18-21UT 2.33 4.67 (G1) 2.00 21-00UT 2.67 4.00 2.33 Rationale: Isolated periods of G1 (Minor) geomagnetic storms are likely on 14 Apr due to a combination of CME 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 13-Apr 15 2024 Apr 13 Apr 14 Apr 15 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 13 2024 0502 UTC. Radio Blackout Forecast for Apr 13-Apr 15 2024 Apr 13 Apr 14 Apr 15 R1-R2 35% 35% 35% R3 or greater 1% 1% 1% Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts over 13-15 Apr. ####018002519#### FXXX12 KWNP 131231 DAYDIS :Product: Forecast Discussion :Issued: 2024 Apr 13 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 (R1-Minor) levels. New Region 3637 (S10E74, Cao/beta) produced an impulsive M2.4/Sf at 13/0502 UTC. Earlier, this region also produced numerous C-class flares. Immediately to the south of Region 3637, new Region 3738 (S17E74, Hsx/alpha) was also numbered. Region 3634 (N27W12, Eai/beta) produced a few C-class flares during the period. Slight growth was observed in Regions 3633 (S08W16, Cso/beta) and 3634. The rest of the spotted regions were either stable or in decay. The faint, halo CME from a filament eruption near S16W20 at 12/0020 UTC was analyzed with an arrival time late on 14 Apr. .Forecast... Solar activity is expected to be low with a chance for M-class flares (R1-R2/Minor-Moderate) on 13-15 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 15 Apr. Solar Wind .24 hr Summary... Solar wind parameters were near nominal levels. Solar wind speed slowly decreased through the period from a high of near 445 to a low of near 380 km/s. Total field ranged from 3-5 nT while the Bz component varied between +4 to -3 nT. Phi angle was mostly positive. .Forecast... A weakly enhanced solar wind environment is expected on 13 Apr due to CH HSS influences. Solar wind conditions are expected to become further enhanced on 14 Apr, through midday 15 Apr, due to the anticipated arrival of CMEs from 11 and 12 Apr in addition to continued CH HSS influences. Geospace .24 hr Summary... The geomagnetic field was at quiet levels. .Forecast... Quiet to unsettled levels are likely on 13 Apr due to CH HSS influences. Periods of G1 (Minor) storming are likely on 14 Apr, followed by periods of active conditions on 15 Apr, due to the arrival and passage of CMEs from 11 and 12 Apr and CH HSS influences.