Routine Space Environment Product (Daily)
Issued by NWS
Issued by NWS
417 FXXX12 KWNP 190031 DAYDIS :Product: Forecast Discussion :Issued: 2025 Aug 19 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 maintained low levels as an isolated C2.2 flare was observed at 18/2152 UTC, emanating from near newly numbered Region 4188 (S09E72, Hax/alpha) as it rotated into view on the eastern limb. Region 4180 (S02W25, Bxo/beta) experienced decay as it lost the penumbra in its trailing spots. Region 4187 (S18E18, Cro/beta) was numbered this period as it quickly emerged, forming rudimentary penumbra in its leading spot. No Earth-directed CMEs were observed in available coronagraph imagery. .Forecast... Solar activity will likely be at very low levels, with a chance for isolated C-class flare activity, through 19-20 August. A slight chance for M-class flares will return on 21 August due to the anticipated return of old regions. Energetic Particle .24 hr Summary... The greater than 2 MeV electron flux reached high levels with a peak flux of 2,220 pfu at 18/0830 UTC. The greater than 10 MeV proton flux was at background levels. .Forecast... The greater than 2 MeV electron flux is expected to be at normal to moderate levels through 21 August as high speed stream influences arrive on 19 August, followed by the potential of periphery influences from a CME that left the Sun on 17 August interacting with the near-Earth environment. Solar Wind .24 hr Summary... Solar wind parameters reflected a relatively mild enhancement. Total field increased from 5-6 nT to a peak of 11 nT as the Bz component of the IMF shifted southward, reaching -7 nT. After that extended southward deflection, Bz remained near neutral or northward. Solar wind speeds gradually rose from an ambient-like state to near 390-400 km/s before gradually declining to ambient-like levels once again. Phi was in the positive solar sector until approximately 18/1424 UTC when a boundary crossing to negative polarity occurred that then lasted until approximately 18/1811 UTC. .Forecast... A disturbed solar wind environment is likely to continue through 21 August due to recurrent, negative polarity CH HSS influences with the corotating interaction region arriving on 19 August. An additional enhancement is also possible on 20 August due to glancing effects from a CME that left the Sun on 17 August. Geospace .24 hr Summary... The geomagnetic field was at quiet levels. .Forecast... The geomagnetic field will likely experience isolated periods of G1 (Minor) geomagnetic storming on 19 and 20 August, due to negative polarity CH HSS effects, followed by a possible glancing blow from a CME that left the Sun on 17 August.