####018002499#### FXXX10 KWNP 241231 DAYTDF :Product: 3-Day Forecast :Issued: 2024 Mar 24 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 Mar 24-Mar 26 2024 is 6.67 (NOAA Scale G3). NOAA Kp index breakdown Mar 24-Mar 26 2024 Mar 24 Mar 25 Mar 26 00-03UT 4.67 (G1) 5.00 (G1) 5.00 (G1) 03-06UT 3.33 6.67 (G3) 4.00 06-09UT 3.67 5.67 (G2) 4.00 09-12UT 3.67 5.00 (G1) 3.67 12-15UT 2.67 4.00 3.00 15-18UT 2.67 3.00 2.33 18-21UT 5.00 (G1) 3.00 2.33 21-00UT 5.67 (G2) 4.00 3.33 Rationale: G1-G2 (Minor-Moderate) geomagnetic storming is expected on 24 Mar due to negative polarity CH HSS effects as well as the arrival of the 23 Mar CME. Activity will likely increase to G3 (Strong) geomagnetic storm conditions early to mid 25 Mar followed by G1 (Minor) storming on 26 Mar. 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 Mar 24-Mar 26 2024 Mar 24 Mar 25 Mar 26 S1 or greater 99% 70% 50% Rationale: S2 (Moderate) solar radiation storm levels are expected to continue through 24 with a chance for reaching S3 (Strong). S1-S2 (Minor-Moderate) levels are likely to continue through 25 Mar with a chance for S1 (Minor) levels on 26 Mar. C. NOAA Radio Blackout Activity and Forecast Radio blackouts reaching the R2 levels were observed over the past 24 hours. The largest was at Mar 23 2024 1402 UTC. Radio Blackout Forecast for Mar 24-Mar 26 2024 Mar 24 Mar 25 Mar 26 R1-R2 90% 90% 90% R3 or greater 40% 40% 40% Rationale: R1-R2 (Minor-Moderate) radio blackouts are expected, with a chance for isolated R3 (Strong) events, through 26 Mar primarily due to the flare potential exhibited by AR 3615. ####018003270#### FXXX12 KWNP 241231 DAYDIS :Product: Forecast Discussion :Issued: 2024 Mar 24 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 3615 (S13W07, Fkc/beta-gamma-delta) produced 16 M-class flares. The largest was an M5.3 at 23/1402 UTC. Region 3615 continued to grow over the period with some consolidation appearing in the leading and trailing areas. Magnetogram imagery showed movement of negative polarity areas in the southern spots. The rest of the spotted regions were relatively stable. No Earth-directed CMEs were observed. .Forecast... Solar activity is expected to continue at moderate (R1-R2/Minor-Moderate) levels with a chance for an X-class flares (R3/Strong) on 24-26 Mar, due primarily to the flare potential of Region 3615. Energetic Particle .24 hr Summary... The greater than 10 MeV proton event that began following the X1.1 flare on 23 Mar continued to be elevated above the S2 (Moderate) threshold. The current peak is 956 pfu at 23/1820 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 continue above the 100 pfu (S2) threshold on 24 Mar, likely reaching the S3 (strong) levels based on current trends. An impending CME arrival may increase the proton flux initially late on 24 Mar to early on 25 Mar. Following the CME arrival, levels are likely to begin to decrease. A chance exists for levels to continue at S1 (Minor) on 26 Mar. The greater than 2 MeV electron flux is expected to be at normal to moderate levels on 24-26 Mar. Solar Wind .24 hr Summary... Solar wind parameters were enhanced under a negative polarity CH HSS. Total field increased initially to between 15-17 nT with periods of negative Bz reaching -14 nT. By 24/0320 UTC, the Bz component decreased to around 5-8 nT. Solar wind speed increased from approximately 350 km/s to the 500-545 km/s range. Phi angle was mostly negative. .Forecast... Continued enhancements from a negative polarity CH HSS are expected through 24 Mar. Between the latter portion of 24 Mar and into 25 Mar, the onset of influence from a CME that left the Sun on 23 Mar is anticipated. Enhancements are likely to continue in to 26 Mar. Geospace .24 hr Summary... The geomagnetic field reached G1-G2 (Minor-Moderate) geomagnetic storm levels late on 23 Mar to early on 24 Mar due to the arrival of a co-rotating interaction region followed by the onset of a negative polarity CH HSS. .Forecast... The geomagnetic field is expected to continue at unsettled to active levels through late on 24 Mar. The onset of influence from a CME that left the Sun on 23 Mar is anticipated late on 24 Mar to early on 25 Mar. G2 (Moderate) conditions are forecast for late on 24 Mar with an increase to G3 (Strong) conditions on 25 Mar. As solar wind enhancements wane, unsettled to G1 (Minor) conditions are likely for 26 Mar.