Routine Space Environment Product (Daily)
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FXXX12 KWNP 310030

:Product: Forecast Discussion
:Issued: 2015 Jul 31 0030 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 continued at very low levels. Region 2390 (S15W52,
Dao/beta) continued to decay, losing most of its intermediate
spots. Region 2393 (N16E46, Cro/beta) exhibited slight growth as it
rotated further onto the visible disk. The remaining numbered regions
showed slight decay and were inactive. No Earth-directed coronal mass
ejections (CME) were observed in available LASCO coronagraph imagery
this period.

Solar activity is expected to remain very low with a chance for C-class
activity for the next three days (31 Jul-02 Aug) as most of the regions
remain relatively stable.

Energetic Particle

.24 hr Summary...
The greater than 2 MeV electron flux was at normal to moderate levels
with a peak flux of 825 pfu observed at 30/1440 UTC. The greater than 10
MeV proton flux remained at background levels through the period.

The greater than 2 MeV electron flux at geosynchronous orbit is
expected to be at normal to moderate levels on all three days (31 Jul-02
Aug), while the greater than 10 MeV proton flux is expected to remain at
background levels (below S1-Minor).

Solar Wind

.24 hr Summary...
The solar wind parameters measured at ACE continued to indicate a
near-ambient solar wind environment early in the period. Wind speeds
increased from near 360 km/s to end-of-period speeds near 420 km/s. The
IMF total field strength increased from between 1-13 nT, while the Bz
component was variable between +9 and -11 nT due to a possible
co-rotating interaction region (CIR) ahead of a negative polarity
coronal hole high speed stream (CH HSS). The phi angle was predominantly
positive (away) early then near 30/1300 UTC switched to a negative
(towards) sector.

An increase in solar wind speed is expected late on day one (31 Jul) due
to effects of an anticipated CIR ahead of a negative polarity CH HSS.
Solar wind speed parameters are expected to remain enhanced through day
three (02 Aug) due to continued CH HSS influences.


.24 hr Summary...
The geomagnetic field was quiet early in the period before increasing to
active levels due to a possible CIR ahead of the expected negative CH

Unsettled to active conditions are expected initially on day one (31
Jul) until late in the period when conditions are expected to increase
to G1 (minor) storm levels due to CH HSS effects. G1 levels are
expected again on day two (01 Aug) as CH HSS influences continue.
Unsettled to active conditions are expected on day three (02 Aug) as CH
HSS effects begin to wane. is the U.S. government's official web portal to all federal, state and local government web resources and services.