Joint USAF/NOAA Report of Solar and Geophysical Activity 31 Jul 2009

:Product: Report of Solar-Geophysical Activity
:Issued: 2009 Jul 31 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 212 Issued at 2200Z on 31 Jul 2009
IA. Analysis of Solar Active Regions and Activity from 30/2100Z
to 31/2100Z: Solar activity was very low. No flares were observed
during the past 24 hours. The solar disk remains spotless.
IB. Solar Activity Forecast: Solar activity is expected to be very
low.
IIA. Geophysical Activity Summary 30/2100Z to 31/2100Z:
The geomagnetic field was at quiet to unsettled levels. Solar wind
observations from the ACE spacecraft indicted the presence of a
coronal hole high speed stream. Velocities increased from around
340 km/s to 420 km/s, with +/- 5nT fluctuations in the IMF Bz.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be at quiet to unsettled levels with a chance for
isolated active conditions for day one (01 August). Predominantly
quiet conditions are expected for days two and three (02-03 August).
III. Event Probabilities 01 Aug-03 Aug
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF Green
IV. Penticton 10.7 cm Flux
Observed 31 Jul 069
Predicted 01 Aug-03 Aug 068/068/068
90 Day Mean 31 Jul 069
V. Geomagnetic A Indices
Observed Afr/Ap 30 Jul 002/003
Estimated Afr/Ap 31 Jul 005/007
Predicted Afr/Ap 01 Aug-03 Aug 007/007-005/005-005/005
VI. Geomagnetic Activity Probabilities 01 Aug-03 Aug
A. Middle Latitudes
Active 20/05/05
Minor storm 05/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 20/05/05
Minor storm 10/01/01
Major-severe storm 05/01/01