Report of Solar-Geophysical Activity

Issued: 2012 Jul 23 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 205 Issued at 2200Z on 23 Jul 2012

IA.  Analysis of Solar Active Regions and Activity from  22/2100Z
to 23/2100Z:  Solar activity was low.  Newly numbered Regions 1527
(N27E64) and 1529 (S12E71) produced the only C-class flares for the
period: a C2/1f flare at 23/1127Z and a C1 flare at 23/1700Z,
respectively.  New Region 1528 (N17E67) was also numbered.  Two CMEs
were observed overnight in LASCO C2 imagery.  The first was
associated with a filament eruption beyond the northwest limb
beginning at 22/1248Z and the second, an asymmetric full-halo
associated with flare activity from old Region 1520 (S16, L=086)
approximately 40 degrees beyond the west limb beginning at 23/0236Z.
These CMEs are not expected to disturb the geomagnetic field.
IB.  Solar Activity Forecast:  Solar activity is expected to be at
very low levels with a chance for C-class events for the forecast
period (24 - 26 July).
IIA.  Geophysical Activity Summary 22/2100Z to 23/2100Z:
The geomagnetic field was at quiet to unsettled levels with intervals
of active to minor storm conditions observed at high latitudes
between 23/1200 - 1800Z. The greater than 10 MeV proton flux at
geosynchronous orbit exceeded the 10 pfu threshold at 23/1545Z.  A
maximum of 12 pfu was reached at 23/1700Z with flux levels still
above threshold as of this report.  An enhancement of the greater
than 100 MeV proton flux at geosynchronous orbit was on-going as
well.  The proton event is likely associated with flare activity
from old Region 1520 that occurred at approximately 23/0235Z. 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 at quiet to unsettled levels with a chance for active
periods on day 1 (24 July) due to effects from a coronal hole high
speed stream.  Quiet to unsettled conditions are expected on day 2
(25 July) as effects begin to diminish.  Mostly quiet conditions are
expected on day 3 (26 July).
III.  Event Probabilities 24 Jul-26 Jul
Class M    01/01/01
Class X    01/01/01
Proton     30/05/01
PCAF       yellow
IV.  Penticton 10.7 cm Flux
Observed           23 Jul 097
Predicted   24 Jul-26 Jul  100/105/110
90 Day Mean        23 Jul 126
V.  Geomagnetic A Indices
Observed Afr/Ap 22 Jul  009/009
Estimated Afr/Ap 23 Jul  007/008
Predicted Afr/Ap 24 Jul-26 Jul  007/015-007/010-006/005
VI.  Geomagnetic Activity Probabilities 24 Jul-26 Jul
A.  Middle Latitudes
Active                20/10/05
Minor storm           10/05/01
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor storm           25/15/10
Major-severe storm    35/05/05