Joint USAF/NOAA Report of Solar and Geophysical Activity 1 August 2011

:Product: Report of Solar-Geophysical Activity
:Issued: 2011 Aug 01 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 213 Issued at 2200Z on 01 Aug 2011
IA. Analysis of Solar Active Regions and Activity from 31/2100Z
to 01/2100Z: Solar activity was low during the past 24 hours. Region
1261 (N18W08) produced the largest event of the period a C4/1F flare
at 01/0732Z. Region 1261 has continued to develop in area and
magnetic complexity and is classified as an Fkc type spot group with
a Beta-Gamma-Delta magnetic configuration. Region 1263 (N127E21) has
maintained it’s Beta-Gamma-Delta classification and produced three
low level C-class events. Region 1260 (N18W36) and Region 1265
(N17W67) remained stable and quiet, while Region 1264 (S23W07) has
decayed to spotless plage.
IB. Solar Activity Forecast: Solar activity is expected to be low
to moderate with a slight chance for a major event for the next
three days (02-04 August). Region 1261 is the most likely source
for a major x-ray event and has a slight chance to produce an
energetic proton event.
IIA. Geophysical Activity Summary 31/2100Z to 01/2100Z:
The geomagnetic field has been quiet to unsettled. Solar wind data
observed at the ACE satellite indicated that the coronal hole high
speed stream has subsided with wind speeds decreasing from 700 km/s
to about 550 km/s during the past 24 hours. A solar sector boundary
crossing was observed at 1305Z.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be predominately quiet to unsettled on day one (02
August) as the effects of the coronal hole high speed stream
continues to wane. Days two and three (03-04 August) are expected
to be quiet.
III. Event Probabilities 02 Aug-04 Aug
Class M 60/60/50
Class X 10/10/05
Proton 10/10/05
PCAF green
IV. Penticton 10.7 cm Flux
Observed 01 Aug 125
Predicted 02 Aug-04 Aug 130/125/125
90 Day Mean 01 Aug 095
V. Geomagnetic A Indices
Observed Afr/Ap 31 Jul 007/008
Estimated Afr/Ap 01 Aug 007/008
Predicted Afr/Ap 02 Aug-04 Aug 007/007-005/005-005/005
VI. Geomagnetic Activity Probabilities 02 Aug-04 Aug
A. Middle Latitudes
Active 05/05/05
Minor storm 05/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/05/05
Minor storm 05/01/01
Major-severe storm 01/01/01