:Product: 0417RSGA.txt
:Issued: 2012 Apr 17 2200 UTC
# Prepared jointly by the U.S. Dept. of Commerce, NOAA,
# Space Weather Prediction Center and the U.S. Air Force.
#
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 108 Issued at 2200Z on 17 Apr 2012
IA.  Analysis of Solar Active Regions and Activity from  16/2100Z
to 17/2100Z:  Solar activity has been low for the past 24 hours. A
long duration C1 flare was observed from new Region 1461 (N13E66) at
17/0809Z. An associated CME became visible in LASCO C2 imagery at
17/0800Z but does not appear to be Earth-directed. A filament
eruption occurred at approximately 17/1330Z near N24W40. The
associated CME was first visible in LASCO C2 imagery at 17/1424Z but
is not expected to be geoeffective. New Region 1460 (N16E26) was
also numbered overnight and is considered a Dso-beta type spot
group. Region 1459 (S15E40) has shown a significant decrease in
areal coverage and is now a Dao-beta type spot group.
IB.  Solar Activity Forecast:  Solar activity is expected to be low
with a slight chance for an M-class flare for the next three days
(18-20 April).
IIA.  Geophysical Activity Summary 16/2100Z to 17/2100Z:
The geomagnetic field was mostly quiet during the past 24 hours. The
greater than 2 MeV electron flux at geosynchronous orbit reached
high levels during the period.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be mostly quiet on days one and two (18-19 April). Quiet
to unsettled conditions are expected with a chance for isolated
active periods on day three (20 April) due to a recurrent Solar
Sector Boundary Crossing (SSBC).
III.  Event Probabilities 18 Apr-20 Apr
Class M    20/15/10
Class X    01/01/01
Proton     01/01/01
PCAF       green
IV.  Penticton 10.7 cm Flux
Observed           17 Apr 114
Predicted   18 Apr-20 Apr  115/115/110
90 Day Mean        17 Apr 112
V.  Geomagnetic A Indices
Observed Afr/Ap 16 Apr  005/005
Estimated Afr/Ap 17 Apr  006/008
Predicted Afr/Ap 18 Apr-20 Apr  004/005-004/005-007/008
VI.  Geomagnetic Activity Probabilities 18 Apr-20 Apr
A.  Middle Latitudes
Active                10/10/25
Minor storm           01/01/10
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor storm           15/15/30
Major-severe storm    10/10/30