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Solar wind parameters indicated the arrival of a co-rotating interaction region (CIR) in advance of a recurrent, negative-polarity CH HSS influence. Phi angle changed from positive to negative at 26/0700 UTC. Wind speed increased from 450 km/s to near 515 km/s after the switch. An additional enhancement was observed at 26/1845 UTC with the arrival of an interplanetary shock at the DSCOVR spacecraft. Density values increased to 34 ppcm, wind speed exceeded 700 km/s, and temperature measurements showed increased values. Total field rose to 21 nT while Bz dropped as low as -18 nT. A corresponding sudden impulse was observed at the GOES-16 spacecraft and at magnetometer sites around the globe. The Fredericksburg Magnetic Observatory, in Virginia, measured the sudden impulse at 34 nT beginning at 26/1925 UTC. There is a 5% chance of solar activity, with a 10% chance of a minor event, a 30% chance of a moderate event, and a 55% chance of a strong event.
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