Routine Space Environment Product (Daily)
Issued by NWS
Issued by NWS
061 FXXX12 KWNP 260031 DAYDIS :Product: Forecast Discussion :Issued: 2026 Aug 26 0030 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 four M-class flares from Region 4513 (N04W04, Ekc/beta-gamma-delta): an M1.9/1n at 25/0126 UTC, an M1.0/Sn at 25/0402 UTC, and M1.8/1n at 25/0640 UTC and an M6.9/1b at 25/1002 UTC. The largest flare of the day, the M6.9/1b, was accompanied by a Type II radio sweep (est. velocity of 603 km/s), a Tenflare (160 sfu) and a CME first observed by LASCO/C2 around 25/1100 UTC. Region 4513 continued to evolve and was also the main responsible for the C-class activity of the day, including a C4.7/Sf at 25/1258 UTC that was associated with a filament eruption visible at CCOR-2 imagery after 25/1345 UTC. There were other three active regions in the visible disk and, along with Region 4513, most of them showed some development during the past 24h: Region 4515 (S07E09, Hsx/alpha), Region 4516 (N16W68, Dso/beta-gamma) and Region 4517 (Dai/beta-gamma). Coronal activity was observed and analyzed during the day, with two CMEs (associated with the M6.9/1b and C4.7/Sf flares) containing Earth-directed components anticipated to impact the Geospace on 28 Aug. A narrow eruption was observed on STEREO/C2 coronagraph imagery around 25/1523 UTC, and a broader one was observed at LASCO/C2 after 25/2012, but further imagery is needed to properly assess their propagation path and possible impact near-Earth. .Forecast... Solar activity will likely to remain at Minor-Moderate (R1-R2) levels, with a slight chance for Strong (R3) activity through 28 Aug, mostly due to the activity and development of Regions 4513 and 4517. Energetic Particle .24 hr Summary... The greater than 2 MeV electron flux reached high levels with a peak flux of 1,610 pfu observed at 25/1705 UTC. The greater than 10 MeV proton flux remained below S1 (Minor) levels, approaching background levels by the end of the period. .Forecast... The greater than 2 MeV electron flux is expected to continue reaching high levels through 27 Aug, returning to moderate levels on 28 Aug. There is a slight chance for the greater than 10 MeV proton flux to reach S1 (Minor) storm levels through 28 Aug, mostly due to the activity, location and development of Region 4513. Solar Wind .24 hr Summary... Solar wind parameters were at undisturbed levels with solar wind speeds between 325-365 km/s, total field around 5 nT and Bz component oscillating between +/-5 nT (mostly positive, pointing to the north, during the day). Phi angle was predominantly negative during the whole period. .Forecast... Nominal solar wind conditions are expected to continue until midday on 27 Aug, when the onset of positive polarity CH HSS is anticipated. Enhanced speeds (up to about 600 km/s) and Phi angle positive are expected after that. Additional solar wind disturbances, with increased solar wind densities and total IMF, are likely on 28 Aug due to the impact of the CMEs discussed above. Geospace .24 hr Summary... The geomagnetic field remained at quiet levels in the past 24hr. .Forecast... The geomagnetic field is expected to be mostly quiet through midday on 27 Aug under ambient solar wind conditions. By mid to late on 27 Aug, unsettled to G1 (Minor) storm levels are likely, due to the onset of CH HSS conditions. G2 (Minor) storms are likely on 28 Aug due to the anticipated impact of the CMEs discussed above.