####018002294#### FXXX10 KWNP 131231 DAYTDF :Product: 3-Day Forecast :Issued: 2024 May 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 6 (NOAA Scale G2). The greatest expected 3 hr Kp for May 13-May 15 2024 is 6.00 (NOAA Scale G2). NOAA Kp index breakdown May 13-May 15 2024 May 13 May 14 May 15 00-03UT 5.67 (G2) 3.67 3.67 03-06UT 6.00 (G2) 4.67 (G1) 3.67 06-09UT 4.00 3.67 2.67 09-12UT 2.67 3.00 2.33 12-15UT 4.67 (G1) 2.67 2.33 15-18UT 3.67 2.00 1.00 18-21UT 3.00 2.00 2.33 21-00UT 3.67 3.67 2.67 Rationale: G1-G3 (Minor-Strong) geomagnetic storms are likely on 13 May and G1 conditions are likely on 14 May as CME influence wanes. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was above S-scale storm level thresholds. Solar Radiation Storm Forecast for May 13-May 15 2024 May 13 May 14 May 15 S1 or greater 60% 60% 5% Rationale: S1 (Minor) solar radiation storms are likely on 13-14 May due to the eruptive potential from Region 3664. C. NOAA Radio Blackout Activity and Forecast Radio blackouts reaching the R3 levels were observed over the past 24 hours. The largest was at May 12 2024 1626 UTC. Radio Blackout Forecast for May 13-May 15 2024 May 13 May 14 May 15 R1-R2 95% 95% 25% R3 or greater 75% 75% 5% Rationale: R1-R3 (Minor-Strong) conditions are expected on 13-14 May due to the flare potential of Region 3664. As the region rotates around the Suns W limb, R1-R2 (Minor-Moderate) probabilities drop to just a chance from the remaining active regions on the Suns visible disk. ####018003791#### FXXX12 KWNP 131231 DAYDIS :Product: Forecast Discussion :Issued: 2024 May 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 high levels. Region 3664 (S19W80, Fkc/beta-gamma-delta) produced an X1.0/1f flare (R3/Strong) at 12/1626 UTC, the strongest of the period. The region also produced a long-duration M6.6 (R2/Moderate) flare at 13/0944 UTC. Associated with the event were Type II (est. 683 km/s) and Type IV radio sweeps as well as a Tenflare. A CME was observed from the region in available EUV imagery but further coronagraph imagery is needed for analysis and modeling. The region continued to evolve as it approached the W limb. Regions 3675 (S05W50, Dsi/beta), 3670 (N20W17, Csi/beta), 3676 (S20E02, Dai/beta-gamma-delta), and 3679 (S09E66, Dai/beta) exhibited growth. Newly numbered Region 3680 was relatively stable as it and a yet unnumbered region rotated around the NE limb. Another region of emerging flux was noted near S08E12. The remaining spotted active regions were either stable or in gradual decay. No Earth-directed CME were observed in available coronagraph imagery. .Forecast... Solar activity is expected to be at high levels over 13-14 May, with M-class (R1-R2/Minor-Moderate) and X-class flares (R3/Strong) expected, due to the flare potential of Region 3664. Solar activity is expected to be low on 15 May with a chance for M-class flares as Region 3664 fully rotates to the far side of the Sun. Energetic Particle .24 hr Summary... The greater than 10 MeV proton event that began at 10/1335 UTC and reached a peak flux of 207 pfu at 10/1745 UTC, ended at 12/1235 UTC. 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 elevated over 13 May with additional proton enhancements at S1 (Minor) storm levels likely over 13-14 May due to the flare potential and location of Region 3664. The greater than 2 MeV electron flux is expected to be at normal to moderate levels on 13 May, and is likely to increase to high levels on 14-15 May following a prolonged period of elevated geomagnetic activity and enhanced solar wind conditions. Solar Wind .24 hr Summary... Solar wind parameters were indicative of weakening CME influences from all the preceding transients. However, conditions remained highly agitated with solar wind speed decreasing gradually from ~900 km/s to ~650 km/s by the end of the reporting period. Total magnetic field strength varied between 5-10 nT and the Bz component was at +/- 8 nT. .Forecast... An enhanced solar wind environment with CME influences is expected to continue on 13 May. Solar wind parameters are expected to continue to wane over 14 May with weak CH HSS influences becoming likely. Ambient solar wind conditions are expected to return by 15 May. Geospace .24 hr Summary... The geomagnetic field reached G2 (Moderate) geomagnetic storm levels due to continued CME activity. Unsettled to active conditions were observed outside after 13/0600 UTC. .Forecast... Periods of G2-G3 (Moderate-Strong) geomagnetic storms are likely on 13 May due to continued CME influence. Active conditions to G1 (Minor) storms are likely on 14 May due to weak CH HSS influences and the possible glancing blow arrival of a CME from 12 May. Unsettled and active levels are expected on 15 May with continued CH HSS influences and possible waning CME influences.