:Product: Report of Solar-Geophysical Activity
:Issued: 2010 Jul 27 2201 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 208 Issued at 2200Z on 27 Jul 2010
IA.  Analysis of Solar Active Regions and Activity from  26/2100Z
to 27/2100Z:  Solar activity increased to low levels. Region 1089
(S23W35) produced a C2 flare at 27/0424Z, as well as occasional
B-class flares. Region 1089 continued to gradually decay in spot
count and area. Regions 1090 (N22E19) and 1091 (N12W86) decayed to
spotless plage regions. No new regions were assigned.
IB.  Solar Activity Forecast:  Solar activity is expected to be at
very low levels. However, there will be a chance for an isolated
C-class flare from Region 1089.
IIA.  Geophysical Activity Summary 26/2100Z to 27/2100Z:
Geomagnetic field activity increased to unsettled to active levels as
a recurrent coronal hole high-speed wind stream continued. The
activity increase was associated with enhanced interplanetary
magnetic field (IMF) intensity (peak 9 nT at 27/0145Z) combined with
intermittent periods of southward IMF Bz (maximum deflection -8 nT
at 27/0216Z) and increased velocities (peak 641 km/sec at 27/0946Z).
IIB.  Geophysical Activity Forecast:  Geomagnetic field activity is
expected to decrease to quiet to unsettled levels during days 1 - 2
(28 - 29 July) as the coronal hole high-speed stream gradually
subsides. Quiet conditions are expected on day 3 (30 July).
III.  Event Probabilities 28 Jul-30 Jul
Class M    01/01/01
Class X    01/01/01
Proton     01/01/01
PCAF       Green
IV.  Penticton 10.7 cm Flux
Observed           27 Jul 083
Predicted   28 Jul-30 Jul  082/082/082
90 Day Mean        27 Jul 075
V.  Geomagnetic A Indices
Observed Afr/Ap 26 Jul  005/006
Estimated Afr/Ap 27 Jul  015/015
Predicted Afr/Ap 28 Jul-30 Jul  008/010-007/008-005/005
VI.  Geomagnetic Activity Probabilities 28 Jul-30 Jul
A.  Middle Latitudes
Active                15/10/05
Minor storm           05/01/01
Major-severe storm    01/01/01
B.  High Latitudes
Active                20/15/10
Minor storm           05/05/01
Major-severe storm    01/01/01