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Here is this week’s space weather and geophysical report, issued 2015 Apr 20 0248 UTC.

Highlights of Solar and Geomagnetic Activity
13 – 19 April 2015

Solar activity was at very low to low levels. Numerous weak to
moderate level C-class flares were observed from Regions 2320 (S12,
L=211, class/area Dac/180 on 07 Apr), 2321 (N13, L=095, class/area
Ekc/620 on 13 Apr) and 2324 (N18, L=062, class/area Dko/410 on 15
Apr). The most significant event of the period occurred from Region
2321 on 18 April when the region produced a C5/1f flare at 18/1419
UTC. Associated with this event was a 7 degree long filament
eruption, centered near N05W16. The filament eruption resulted in an
asymmetric, faint full-halo CME, first visible in SOHO/LASCO C2
imagery at 18/1524 UTC.

No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit was at
normal levels on 13-15 April and high levels on 16-19 April.

Geomagnetic field activity began the period on 13-14 April at quiet
to active levels under the influence of a weak transient. By midday
on 15 April, field activity increased to active to minor storm
(G1-minor) levels as a co-rotating interaction region (CIR), in
advance of a negative polarity coronal hole high speed stream (CH
HSS), influenced the magnetic field of Earth. Geomagnetic activity
increased to major storm (G2-moderate) levels late on 16 April due
to CH HSS effects and continued at active to minor storm levels
through midday on 17 April. Field activity relaxed to quiet to
unsettled levels through the remainder of the summary period as CH
HSS effects waned.

During the period, ACE solar wind parameters measured a high wind
speed of 784 km/s on 17/0408 UTC with a low speed of 286 km/s on
14/0004 UTC. Total field (Bt) ranged from about 1-17 nT while the Bz
component varied between +13 to -12 nT. The phi angle was generally
in a negative (towards) orientation with intermittent periods of
rotation to a positive (away) sector.

Forecast of Solar and Geomagnetic Activity
20 April – 16 May 2015

Solar activity is expected to be very low to low with a slight
chance for moderate (R1-R2/minor-moderate) levels through 24 April
due to the flare potential from Region 2321. Very low to low levels
are expected from 25 April through 06 May. From 06-16 May, activity
levels are expected to increase to a chance for
(R1-R2/minor-moderate) levels upon the return of old Region 2321
(N11, L=092).

No proton events are expected at geosynchronous orbit, barring any
significant flare activity.

The greater than 2 MeV electron flux at geosynchronous orbit is
expected to be at moderate to high levels from 20 April-06 May,
normal to moderate levels from 07-12 May and moderate to high levels
from 13-16 May.

Geomagnetic field activity is expected to be at G1 (minor)
geomagnetic storm levels on 21 and 22 April due to CME effects.
Field activity is expected to be at G1 (minor) geomagnetic storm
levels on 14 May with unsettled to active conditions expected on 20,
25, 29-30 April and 01, 13 and 15 May, all due to CH HSS effects.
Quiet to unsettled field activity is expected for the remainder of
the outlook period.

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Live Aurora mapping is at http://aurora.sunspotwatch.com/

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