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000
FXXX12 KWNP 310031
DAYDIS

:Product: Forecast Discussion
:Issued: 2014 Jul 31 0030 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC contact on the Web
# http://www.swpc.noaa.gov/wwire.html
#
#             Forecast Discussion
#
Solar Activity

.24 hr Summary...
A 31 degree filament eruption centered near N08E32 was observed in
SDO/AIA imagery beginning around 30/0400 UTC. A CME subsequently
appeared in SOHO/LASCO C2 imagery at 30/0700 UTC and was also captured
in STEREO A and B COR2 imagery.  Preliminary analysis indicated the
ejecta was moving around 700 km/s and had an Earth-directed component.
An initial WSA-Enlil model run suggests a glancing blow early on 02
August. However, the model solar wind speeds appear to be over-estimated
and arrival is expected mid to late on 02 August.  Timing will continue
to be refined as additional analysis and modeling are carried out.

Solar activity remained at low levels.  The largest flare of the period
was a C9/1F from Region 2127 (S09E36, Dkc/beta-gamma) at 30/1617 UTC.
Region 2127 grew during the period, and remained the largest and most
productive region on the visible disk.  The second largest region, 2130
(S08E56, Dkc/beta-gamma-delta) remained stable but produced a C3 at
30/0246 UTC.

.Forecast...
Solar activity is expected to be low with a chance for M-class (R1-R2,
Minor-Moderate) flares for the forecast period (31 Jul-02 Aug).


Energetic Particle

.24 hr Summary...
The greater than 2 MeV electron flux at geosynchronous orbit was at
normal levels and the greater than 10 MeV proton flux at geosynchronous
orbit was at background levels.

.Forecast...
The greater than 2 MeV electron flux at geosynchronous orbit is expected
to be at normal levels and the greater than 10 MeV proton flux at
geosynchronous orbit is expected to remain at background levels (Below
S1-Minor) for the next three days (31 Jul-02 Aug).


Solar Wind

.24 hr Summary...
The solar wind environment was nominal.  Solar wind speed at the ACE
spacecraft reached a peak 358 km/s at 30/0148Z. Total IMF reached 5 nT
at 30/0333Z. The maximum southward component of Bz reached -5 nT at
30/0244Z.  Phi was generally negative.

.Forecast...
Solar wind parameters are expected to be at nominal levels for the first
two days of the forecast (31 Jul-01 Aug).  Mid to late on 02 August,
disturbed conditions are expected with the passage of the glancing blow
from the CME described above.


Geospace

.24 hr Summary...
The geomagnetic field was quiet with an isolated unsettled period from
30/0000-0300 UTC.

.Forecast...
The geomagnetic field is expected to be mostly quiet (Below G1-Minor)
for the forecast period (31 Jul-02 Aug).  There is a chance for
unsettled to active conditions mid to late on 02 Aug with the expected
arrival of a glancing blow from the CME described above.