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000
FXXX12 KWNP 281231
DAYDIS

:Product: Forecast Discussion
:Issued: 2014 Jul 28 1230 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...
Solar activity was at low levels. The largest event of the period was a
C1 flare from Region 2127 (S08E68, Dao/beta) at 27/1418 UTC. New Region
2029 (S06W00, Cro/beta) was numbered overnight. The remaining seven
regions were unremarkable and lacked significant flare production. There
were no Earth-directed coronal mass ejections (CMEs) observed in
satellite imagery during the period.

.Forecast...
Solar activity is likely to be at low levels with a slight chance for
M-class flaring (R1-Minor) for the forecast period (28-30 Jul).

Energetic Particles

.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 (28-30 Jul).

Solar Wind

.24 hr Summary...
Solar wind parameters, measured at the ACE spacecraft, indicated the
arrival of a negative polarity coronal hole high-speed stream (CH HSS).
Wind speed began the period at 375 km/s, displayed a steady decline to a
low of 318 km/s at 28/0259 UTC, and reached a high value of 435 km/s at
28/0654 UTC. At approximately 28/0312 UTC, wind speed began to climb in
response to the arrival of the CH HSS. The total interplanetary magnetic
field (Bt) ranged between +1 to +12 nT. The Bz component was
predominately positive until the arrival of the CH HSS when it briefly
dropped to a low of -8 nT before returning to a positive value. The phi
angle was oriented in a positive (away) solar sector until approximately
28/0312 UTC when a solar sector boundary crossing into negative
(towards) territory occurred.

.Forecast...
Enhanced solar wind conditions are expected for the remainder of day one
(28 Jul) and into day two (29 Jul) due to the continued influence of the
CH HSS. A slow return to nominal solar wind parameters is
expected by day three (30 Jul).

Geospace

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

.Forecast...
The geomagnetic field is expected to be at quiet to active levels for
the remainder of day one (28 Jul) due to continued influence from a
negative polarity CH HSS. Quiet to unsettled conditions are expected on
day two (29 Jul) as CH HSS effects begin to wane. A return to mostly
quiet conditions is expected by day three (30 Jul).