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:Product: 04301230forecast_discussion.txt
:Issued: 2014 Apr 30 1230 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
Solar Activity
.24 hr Summary...
Solar activity was low. Low-level C-class flares occurred from Regions
2049 (S07E36, Dki/beta-gamma) and 2050 (N12E38, Hsx/alpha). Region 2049
showed gradual spot and penumbra development and a weak mix of
polarities in its intermediate portion. Region 2050 was largely
unremarkable during the period. Region 2047 (S18E07, Dai/beta) showed
gradual spot and penumbra development in its intermediate portion and
produced a B9/Sf flare at 29/2254 UTC. SDO images showed coronal dimming
and a post-eruptive loop structure associated with this B9 flare,
suggestive of a coronal mass ejection (CME). A partial-halo CME was seen
off the east limb in LASCO C2 images beginning at around 30/0024 UTC and
may have been associated with the B9 event. Further analysis will be
required to determine if this CME had an Earth-directed component. A
halo-CME was seen in LASCO C2 images beginning around 29/2324 UTC, but
was likely a far side event, based upon STEREO-A EUV 195 images. Region
2048 (N20W72, Dso/beta) produced a B-class flare and showed no
significant change during the period.
.Forecast...
Solar activity is likely to be low during the period (Apr 30 - May 02)
with a slight chance for an M-class flare (R1-R2, Minor-Moderate).
Energetic Particle
.24 hr Summary...
The greater than 2 MeV electron flux at geosynchronous orbit was at
normal to moderate levels. 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 during the period (Apr 30 - May 02). The greater
than 10 MeV proton flux at geosynchronous orbit is expected to be at
background levels during the period.
Solar Wind
.24 hr Summary...
ACE data indicated the onset of a minor disturbance at around 29/1939
UTC. An initial assessment indicated the possible onset of a coronal
hole high-speed stream (CH HSS), but further analysis of ACE IMF and
temperature profiles suggested a transient feature of some kind, rather
than a CH HSS. The disturbance began with a 4nT jump in IMF Bt, along
with a southward turn of IMF Bz that persisted through the remainder of
the period (maximum southward deflections to -9 nT after 30/0000 UTC).
Following the onset, a gradual increase in wind speed occurred until
around 30/0100 UTC, with wind speed averaging about 310 km/s thereafter
(peak speed 322 km/s at 30/0255 UTC). IMF Phi data indicated a variable
solar-sector orientation until approximately 30/0300 UTC, then settled
into a negative-polarity (toward) sector for the rest of the period.
.Forecast...
A gradual recovery to nominal solar wind conditions is expected by late
on Apr 30 as the current disturbance subsides. Nominal conditions are
expected during May 01 - 02.
Geospace
.24 hr Summary...
The geomagnetic field was at quiet to active levels (less than G1 -
Minor). Activity increased to unsettled to active levels after 29/2100
UTC associated with the solar wind disturbance described above.
.Forecast...
Field activity is expected to decrease to quiet to unsettled levels
during the latter half of Apr 30 as the current disturbance subsides.
Quiet conditions are expected during May 01 - 02.