Routine Space Environment Product (Daily)
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FXXX12 KWNP 241231

:Product: Forecast Discussion
:Issued: 2017 May 24 1230 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC contact on the Web
#             Forecast Discussion
Solar Activity

.24 hr Summary...
Solar activity remained very low. Region 2659 (N13W12, Cro/beta) grew in
spot count and is now the only spotted region on the disk. The other
three regions decayed to plage areas. No Earth-directed CMEs were
observed during the summary period.

Solar activity is expected to be very low, with a slight chance for
C-class flares, throughout the forecast period (24-26 May).

Energetic Particles

.24 hr Summary...
The greater than 2 MeV electron flux reached high levels with a peak
flux of 9,333 pfu observed at 23/1430 UTC. The greater than 10 MeV
proton flux remained at background values.

The greater than 2 MeV electron flux is expected to reach high levels,
with a chance for very high levels, on days one and two (24-25 May) of
the forecast period in response to elevated wind speeds from CH HSS
influence. By day three (26 May), the arrival of the 23 May CME is
likely to cause a redistribution of particles, returning flux levels to
near background conditions. The greater than 10 MeV proton flux is
expected to continue at background levels.

Solar Wind

.24 hr Summary...
Solar wind parameters were indicative of persistent, but waning CH HSS
influence. Solar wind speeds gradually decreased from 520 km/s to 480
km/s. Total field (Bt) was steady near 4 nT, while the Bz component
fluctuated slightly between +/-4 nT. The phi angle remained in a
negative sector during the period.

Solar wind parameters are expected to remain slightly enhanced, yet
continue to slowly diminish on days one and two (24-25 May) as CH HSS
influences continue to wane. Mid to late day on day three (26 May),
solar wind parameters are expected to become enhanced and disturbed with
the arrival of the 23 May CME.


.24 hr Summary...
The geomagnetic field was quiet.

The geomagnetic field is expected to be at quiet to unsettled levels on
day one (24 May) as CH HSS effects persist. A decrease to mostly quiet
levels is expected by day two (25 May) as the negative polarity CH HSS
moves out of a geoeffective position. Unsettled to active conditions are
expected, with a slight chance for G1-Minor storm conditions, by midday
on day three (26 May), with the arrival of the 23 May CME. is the U.S. government's official web portal to all federal, state and local government web resources and services.