Routine Space Environment Product (Daily)
Issued by NWS
Issued by NWS
374 FXXX12 KWNP 251231 DAYDIS :Product: Forecast Discussion :Issued: 2026 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 high levels. Regions 4419 (N17W86, Dso/beta-gamma) and 4423 (S07E22, Dai/beta-delta) were the main contributors to the flare activity. Region 4419 produced the largest flare of the period, an M6.4/1f flare at 24/1815 UTC. Region 4423 added the majority of the flares, including an M1.7/1f flare at 24/1301 UTC, an M1.3/Sf flare at 25/0759 UTC, as well as several C-class flares. Newly numbered Region 4425 (N06E69, Dac/beta-gamma) contributed a couple of C-class flares as well. Initial analysis of the CME associated with the M6.4 flare, mentioned above, indicated most of the ejecta will likely be ahead of and above Earth. Additional modeling is currently underway. There was no indication in available coronagraph imagery of a CME associated with the M1.3 flare that peaked at 25/0759 UTC. There are seven numbered regions on the visible disk. Analysis of Region 4419 is increasingly difficult due to its proximity to the western limb. Region 4420 (N17E03, Fki/beta-gamma-delta) exhibited continued growth, especially in its intermediary spots, and added to its overall length. Region 4423 (S05E22, Dai/beta-delta) continued to evolve, displaying continued shearing and rotation in its trailing spots. Region 4424 (N17E37, Dao/beta) noted initial growth early in the period, but has since stabilized. Region 4425 was also difficult to analyze due to foreshortening near the east limb. Region 4426 (N12W32, Dso/beta) developed during the period and was numbered, but was inactive. Region 4421 (S12E02, Hsx/alpha) remained stable and inactive. .Forecast... Solar activity is expected to be at low levels, with M-class flares (R1-R2-Moderate) likely, and a chance for X-class (R3/Strong or greater) flares through 27 Apr, primarily driven by the complexity of Regions 4419, 4420, 4423, and 4425. Energetic Particle .24 hr Summary... The greater than 2 MeV electron flux at geosynchronous orbit reached high levels with a peak of 5,740 pfu at 24/1820 UTC. The greater than 10 MeV proton flux at geosynchronous orbit was slightly elevated, but remained near background levels. .Forecast... The greater than 2 MeV electron flux is expected to be at moderate to high levels through 27 Apr. The greater than 10 MeV proton flux is expected to remain at background levels, though there is a chance for levels to exceed S1 (Minor) solar radiation storm thresholds due to the flare activity of Region 4419 as it rotates toward the western limb, and Region 4420 as it approaches central solar meridian. Chances diminish to a slight chance on 26-27 Apr. Solar Wind .24 hr Summary... Solar wind parameters reflected near-background conditions. Total field strength averaged between 3-9 nT for most of the period, the Bz component varied between +/- 5 nT, and solar wind speeds remained between 350 and 450 km/s. Phi angle was predominantly negative until just after 25/0000 UTC when it shifted into a positive orientation. .Forecast... Mild enhancements are possible in the solar wind environment on 25 Apr due to the likely onset of a +CH HSS. Further enhancements are anticipated on 25-26 Apr with the arrival of the glancing influence from the 23 Apr CME. Geospace .24 hr Summary... The geomagnetic field was quiet to unsettled. .Forecast... The geomagnetic field is expected to be mostly quiet to unsettled for most of 25 Apr, with isolated active periods possible, as the +CH HSS moves into a geoeffective position. Isolated G1-G2 (Minor-Moderate) geomagnetic storming conditions are possible late on 25 Apr into early 26 Apr in response to the arrival of the glancing CMEs. Quiet to unsettled conditions are then anticipated on 27 Apr as CME and +CH HSS influences subside.