Routine Space Environment Product (Daily)
Issued by NWS
Issued by NWS
248 FXXX12 KWNP 180031 DAYDIS :Product: Forecast Discussion :Issued: 2026 Aug 18 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 was at low levels. The majority of the C-class activity originated from Regions 4107 (N04W41, Eki/beta-gamma) and 4510 (N12W68, Cai/beta). The largest flare was a C3.2 at 17/1747 UTC from Region 4510. Growth and consolidation was observed in Region 4507. Slight growth was observed in Regions 4506 (N12W58, Dao/beta) and 4510. Umbral separation occurred in Region 4508 (N08W09, Cao/beta). A Type II radio sweep (825 km/s) report appeared to be associated with a C2.0 flare at 17/1653 UTC from Region 4510. A narrow CME was observed off the WNW limb at 17/1845 UTC. Further analysis will be conducted as imagery becomes available, however an Earth-directed component is unlikely. .Forecast... Solar activity is expected to be low with a chance for M-class flares (R1-R2, Minor-Moderate) on 18-20 Aug. Energetic Particle .24 hr Summary... The greater than 2 MeV electron flux at geosynchronous orbit was at normal to moderate levels. The greater than 10 MeV proton flux at geosynchronous orbit remained at background levels. .Forecast... The greater than 2 MeV electron flux is likely to remain at low to moderate levels 18-19 Aug, with a chance for high levels on 20 Aug due to HSS influence. The greater than 10 MeV proton flux is expected to remain at background levels through 20 Aug. Solar Wind .24 hr Summary... Solar wind parameters became enhanced after 17/1720 UTC, possibly due to flanking influences from the 14 Aug CME or a CIR preceding a negative polarity CH HSS. Total field increased from 5 nT to 9-13 nT while the Bz component was between +10/-11 nT. Solar wind speed increased from approximately 300 km/s to near 350 km/s. Phi angle was variable. .Forecast... CME or CIR influences are expected to continue into 18 Aug followed by a transition into a negative polarity CH HSS later on 18 Aug. HSS conditions are expected to continue through 20 Aug. Geospace .24 hr Summary... The geomagnetic field was quiet to unsettled. .Forecast... Unsettled to active levels, with a chance for G1 (Minor) storm conditions are expected on 18 Aug as possible CME or CIR activity persists. Unsettled to active levels are expected on 19-20 Aug, with G1 (Minor) storming likely on 19 Aug due to HSS onset.