Joint USAF/NOAA Report of Solar and Geophysical Activity 10 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 10 2200 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 101 Issued at 2200Z on 10 Apr 2012

IA. Analysis of Solar Active Regions and Activity from 09/2100Z
to 10/2100Z: Solar activity has been at very low levels for the past
24 hours. A new region, Region 1454 (S13E70), was numbered today as
it rotated onto the east limb.

IB. Solar Activity Forecast: Solar activity is expected to be at
very low levels for the next three days (11 – 13 April).

IIA. Geophysical Activity Summary 09/2100Z to 10/2100Z:
The geomagnetic field has been at predominantly quiet levels for the
past 24 hours. Solar wind speeds, as measured by the ACE spacecraft,
varied around 320 – 360 km/s.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be at quiet to unsettled levels on day one (11 April) as
effects from a CME, observed on 7 April, are possible. Quiet to
unsettled levels with a chance for active levels are expected on
days two and three (12 – 13 April) as a coronal hole high speed
stream becomes geoeffective.

III. Event Probabilities 11 Apr-13 Apr
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 10 Apr 093
Predicted 11 Apr-13 Apr 090/090/090
90 Day Mean 10 Apr 115

V. Geomagnetic A Indices
Observed Afr/Ap 09 Apr 007/003
Estimated Afr/Ap 10 Apr 006/006
Predicted Afr/Ap 11 Apr-13 Apr 007/008-008/012-007/012

VI. Geomagnetic Activity Probabilities 11 Apr-13 Apr
A. Middle Latitudes
Active 20/25/30
Minor storm 05/05/10
Major-severe storm 01/01/01
B. High Latitudes
Active 30/35/35
Minor storm 25/20/20
Major-severe storm 01/05/05