Joint USAF/NOAA Report of Solar and Geophysical Activity 09 April 2012

Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Weather Prediction Center and the U.S. Air Force.
Updated 2012 Apr 09 2200 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 100 Issued at 2200Z on 09 Apr 2012

IA. Analysis of Solar Active Regions and Activity from 08/2100Z
to 09/2100Z: Solar activity has been at low levels for the past 24
hours with two C-class events observed. Region 1450 (N15W90)
produced a C2 event at 0122Z. Around the vicinity of plage Region
1451 (N17W73), a C3 x-ray event was observed at 1244Z. Associated
with this event were both a Type II radio sweep, with an estimated
plane of sky velocity of 767 km/s and a west-limb CME, first visible
in LASCO C2 imagery at 1325Z. Initial analysis indicates the CME,
associated with this event, is non-Earth directed.

IB. Solar Activity Forecast: Solar activity is expected to be at
very low levels with a slight chance for C-class flares for the next
three days (10 – 12 April) as Regions 1452 (N18W51) and 1451
continue to weaken and rotate off the west limb.

IIA. Geophysical Activity Summary 08/2100Z to 09/2100Z:
The geomagnetic field has been at quiet levels for the past 24 hours.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be at quiet levels on day one (10 April) and at quiet
to unsettled levels on days two and three (11-12 April), as possible
CME effects and the arrival of elevated solar wind from a favorable
positioned coronal hole arrive.

III. Event Probabilities 10 Apr-12 Apr
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF Green

IV. Penticton 10.7 cm Flux
Observed 09 Apr 095
Predicted 10 Apr-12 Apr 095/095/090
90 Day Mean 09 Apr 115

V. Geomagnetic A Indices
Observed Afr/Ap 08 Apr 004/004
Estimated Afr/Ap 09 Apr 003/004
Predicted Afr/Ap 10 Apr-12 Apr 005/005-007/008-007/008

VI. Geomagnetic Activity Probabilities 10 Apr-12 Apr
A. Middle Latitudes
Active 10/20/20
Minor storm 05/05/05
Major-severe storm 01/01/01
B. High Latitudes
Active 15/25/25
Minor storm 10/10/10
Major-severe storm 01/05/05