:Product: 0419RSGA.txt
:Issued: 2011 Apr 19 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 109 Issued at 2200Z on 19 Apr 2011
IA.  Analysis of Solar Active Regions and Activity from  18/2100Z
to 19/2100Z:  Solar activity has been at low levels for the past 24
hours. New Region 1195 (S16E68) rotated onto the visible disk, early
in the period, as a Dao sunspot group. Before being numbered, Region
1195 produced several C-class events off the east limb, as well as
the largest event of the past 24 hours, a C1 flare at 18/0512Z.
Region 1193 (N17W08) continues to evolve and has grown into a
beta-gamma magnetic classification.
IB.  Solar Activity Forecast:  Solar activity is expected to be at
low levels with a slight chance for M-class activity for the next
three days (20-22 April).
IIA.  Geophysical Activity Summary 18/2100Z to 19/2100Z:
The geomagnetic field has been at quiet levels for the past 24 hours.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be at quiet to unsettled levels with a chance for
isolated active periods for the next three days (20-22 April).
Heightened activity levels are expected due to the arrival, early on
day 1, of a coronal hole high-speed stream (CH HSS). Effects from
the CH HSS are expected to last about 2 days. Late on day 2, a
slow-moving CME is expected to become geoeffective with effects
lasting through day 3.
III.  Event Probabilities 20 Apr-22 Apr
Class M    15/15/15
Class X    01/01/01
Proton     01/01/01
PCAF       Green
IV.  Penticton 10.7 cm Flux
Observed           19 Apr 111
Predicted   20 Apr-22 Apr  110/110/110
90 Day Mean        19 Apr 104
V.  Geomagnetic A Indices
Observed Afr/Ap 18 Apr  008/010
Estimated Afr/Ap 19 Apr  005/005
Predicted Afr/Ap 20 Apr-22 Apr  010/010-010/010-010/010
VI.  Geomagnetic Activity Probabilities 20 Apr-22 Apr
A.  Middle Latitudes
Active                35/25/25
Minor storm           10/05/05
Major-severe storm    01/01/01
B.  High Latitudes
Active                30/30/30
Minor storm           15/10/10
Major-severe storm    05/01/01