Solar Weather Forecast Updated 4-22-17
K-indices of 5 or greater indicate storm-level geomagnetic activity around earth.
:Product: Forecast Discussion :Issued: 2017 Apr 22 1230 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # Solar Activity .24 hr Summary... Solar activity was very low. The largest solar event of the period was a B9/Sf flare at 22/0034 UTC from Region 2651 (N12E23, Cao/beta). Region 2651 produced additional B-class flare activity and showed minor development in its intermediate spot group. Region 2652 (N13E38) decayed to plage. Region 2653 (S09E66, Hax/alpha) was stable and absent of significant flare activity. There were no Earth-directed CMEs observed in available satellite imagery. .Forecast... Solar activity is expected to be very low with a chance for C-class flare activity over the next three days (22-24 Apr). Energetic Particles .24 hr Summary... The greater than 2 MeV electron flux was at normal to high levels with a peak flux of 2,810 pfu observed at 21/1545 UTC. The greater than 10 MeV proton flux remained at background values. .Forecast... The greater than 2 MeV electron flux is expected to be at normal to moderate levels on days one and two (22-23 Apr). High levels are likely on day three (24 Apr) due to increased geomagnetic activity associated with CH HSS effects and the likely passage of a transient feature. No solar radiation storms are expected during the forecast period. Solar Wind .24 hr Summary... Solar wind parameters, as measured by the DSCOVR spacecraft, were indicative of combined effects of the 18 April CME and a recurrent, negative polarity CH HSS. Wind speed increased from starting values near 500 km/s to approximately 750 km/s towards the end of the period. Total field (Bt) ranged between 5 and 14 nT while the Bz component reached a maximum southward value of -12 nT with several spans of sustained negative conditions. Phi angle abruptly transitioned from a positive sector to a negative sector at approximately 21/1545 UTC. .Forecast... Enhancements in the solar wind are likely to be observed over the next three days (22-24 Apr) due to combined effects of the 18 Apr CME and the influence of a recurrent, negative polarity CH HSS. Geospace .24 hr Summary... The geomagnetic field was at quiet to G2 (Moderate) storm levels due to the likely passage of a transient feature combined with the onset of a CIR preceding a recurrent, negative polarity CH HSS influence. .Forecast... The geomagnetic field is expected to reach G2 (Moderate) storm levels during the remainder of day one (22 Apr) due to the current enhancement in the solar wind environment. G2 (Moderate) storm levels are likely on day two (23 Apr) from the negative polarity CH HSS. Day three (24 Apr) is expected to continue to observe active to G1 (Minor) storm levels through the day as the CH HSS effects persists.