Status Report

Joint USAF/NOAA Report of Solar and Geophysical Activity 31 July 2012

By SpaceRef Editor
July 31, 2012
Filed under , , ,

:Product: Report of Solar-Geophysical Activity
:Issued: 2012 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 213 Issued at 2200Z on 31 Jul 2012
IA. Analysis of Solar Active Regions and Activity from 30/2100Z
to 31/2100Z: Solar activity was low. The largest of the C-class
flares were an impulsive C6 at 31/0000Z from new Region 1538
(S23E68) and a long-duration C5 at 31/1130Z from Region 1535
(N18E51). Both flares had associated Type II (estimated speeds of
730 and 880 km/s, respectively) and Type IV radio sweeps along with
coronal mass ejections seen off the East limb in SOHO/LASCO C2
imagery. Another CME was observed in SOHO/LASCO C2 imagery off the
southwest limb associated with a filament eruption seen in SDO/AIA
171 imagery at 31/0846Z. None of the CMEs are expected to be
geoeffective. New Region 1537 (N12E76) rotated onto the northeast
limb and was numbered today.
IB. Solar Activity Forecast: Solar activity is expected to be low
with a chance for M-class flares.
IIA. Geophysical Activity Summary 30/2100Z to 31/2100Z:
The geomagnetic field was quiet.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be mostly quiet on day 1 (01 August). On day 2 (02
August), geomagnetic activity is expected to be at quiet to
unsettled levels with possible isolated active periods due to
effects from the 28 July CME. Conditions are expected to be quiet
to unsettled on day 3 (03 August).
III. Event Probabilities 01 Aug-03 Aug
Class M 35/35/35
Class X 05/05/05
Proton 05/05/05
PCAF Green
IV. Penticton 10.7 cm Flux
Observed 31 Jul 140
Predicted 01 Aug-03 Aug 140/145/150
90 Day Mean 31 Jul 126
V. Geomagnetic A Indices
Observed Afr/Ap 30 Jul 011/015
Estimated Afr/Ap 31 Jul 006/006
Predicted Afr/Ap 01 Aug-03 Aug 006/005-008/010-007/008
VI. Geomagnetic Activity Probabilities 01 Aug-03 Aug
A. Middle Latitudes
Active 05/20/15
Minor storm 01/10/05
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor storm 15/25/20
Major-severe storm 05/30/20

SpaceRef staff editor.