Status Report

Joint USAF/NOAA Report of Solar and Geophysical Activity 29 Apr 2012

By SpaceRef Editor
April 29, 2012
Filed under , , ,

:Product: Report of Solar-Geophysical Activity
:Issued: 2012 Apr 29 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 120 Issued at 2200Z on 29 Apr 2012
IA. Analysis of Solar Active Regions and Activity from 28/2100Z
to 29/2100Z: Solar activity was at low levels due to low-level
C-class events from Regions 1465 (S18W80), 1466 (N13W65), 1467
(N12E04), 1469 (S19W01) and 1471 (S23E57). New Region 1472 (S29E40)
emerged on the disk as a simple bi-polar group. GONG H-alpha and
SDO/AIA 304 imagery observed a filament eruption along a six degree
long channel centered near N06E36, just to the SE of Region 1467.
This eruption occurred during the period 28/1800 – 2000Z. Associated
multiple CME activity was visible off the east limb as observed in
LASCO/C2 imagery at 28/1936Z and 28/2024Z. At the time of this
report, analysis was ongoing as to the geoeffective nature of these
IB. Solar Activity Forecast: Solar activity is expected to be low
for the next three days (30 April – 02 May).
IIA. Geophysical Activity Summary 28/2100Z to 29/2100Z:
The geomagnetic field was at quiet to unsettled levels. Through the
period, ACE solar wind velocities ranged between 380 to 440 km/s
while the Bz component of the interplanetary magnetic field did not
vary much beyond +/- 4 nT. 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 predominately quiet levels for day one (30 April).
By days two and three (01 – 02 May), quiet to unsettled levels with
a slight chance for isolated active periods are expected as a
coronal hole high speed stream moves into a geoeffective position.
III. Event Probabilities 30 Apr-02 May
Class M 10/10/10
Class X 01/01/01
Proton 01/01/01
PCAF green
IV. Penticton 10.7 cm Flux
Observed 29 Apr 116
Predicted 30 Apr-02 May 115/115/110
90 Day Mean 29 Apr 112
V. Geomagnetic A Indices
Observed Afr/Ap 28 Apr 005/005
Estimated Afr/Ap 29 Apr 005/006
Predicted Afr/Ap 30 Apr-02 May 004/005-007/008-007/008
VI. Geomagnetic Activity Probabilities 30 Apr-02 May
A. Middle Latitudes
Active 10/15/15
Minor storm 01/01/05
Major-severe storm 01/01/01
B. High Latitudes
Active 10/20/20
Minor storm 01/05/05
Major-severe storm 01/01/01

SpaceRef staff editor.