Routine Space Environment Product (Daily)
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FXXX12 KWNP 251230

:Product: Forecast Discussion
:Issued: 2016 May 25 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 was very low. The largest solar event of the period was a
B9/Sf flare at 24/2107 UTC from Region 2546 (S07W70, Hhx/alpha). Region
2548 (N13W15, Dso/beta) developed penumbra in both its leader and
trailer spots and provided low level B-class flaring. There were no
Earth-directed CMEs observed in available satellite imagery during the
reporting period.

Solar activity is expected to be very low with a chance for C-class
flares all three days (25-27 May).

Energetic Particles

.24 hr Summary...
The 2 MeV electron flux was at moderate levels while the greater than 10
MeV proton flux remained at background values.

The greater than 2 MeV electron flux is expected to continue at moderate
levels on day one (25 May). Normal to moderate levels are expected on
days two and three (26-27 May) due to electron redistribution from CIR
and CH HSS effects. 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 near background conditions.
Solar wind speed was steady at approximately 400 km/s. Total field (Bt)
ranged between 1 and 5 nT while the Bz component reached a maximum
southward deflection of -2 nT. Phi angle was positive.

The solar wind environment is expected to continue at near background
levels for the remainder of day one (25 May). A solar sector boundary
change (SSBC) is expected late on day one through day two (26 May).
Following the SSBC, a weak CIR ahead of an isolated, negative-polarity
CH HSS is expected later on day two. The CH HSS is expected to rotate
into a geoeffective position by day three (27 May) with an expected
increase in solar wind speed.


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

The geomagnetic field is expected to be mostly quiet with an isolated
period of unsettled activity late on day one (25 May) due to a SSBC.
Quiet to unsettled levels with an isolated period of active conditions
are likely on day two (26 May) due to the anticipated arrival of a CIR
in advance of a CH HSS. Quiet to active levels are expected to continue
on day three (27 May) as CH HSS effects persist. is the U.S. government's official web portal to all federal, state and local government web resources and services.