Joint USAF/NOAA Report of Solar and Geophysical Activity 19 March 2011

:Product: Report of Solar-Geophysical Activity
:Issued: 2011 Mar 19 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 078 Issued at 2200Z on 19 Mar 2011
IA. Analysis of Solar Active Regions and Activity from 18/2100Z
to 19/2100Z: Solar activity was at very low levels. Region 1175
(N14W22) grew both in areal coverage and spot count and remained a
simple bi-polar group. The remainder of the disk and limb was quiet
and stable.
IB. Solar Activity Forecast: Solar activity is expected to be at
predominately very low levels with a chance for C-class activity on
day one (20 March). Days two and three (21 – 22 March) will see an
increasing chance for C-class activity, with a slight chance for
isolated M-class activity, due to the return of old Regions 1165
(S20, L=198) and 1164 (N24, L=179).
IIA. Geophysical Activity Summary 18/2100Z to 19/2100Z:
The geomagnetic field was quiet. Solar wind velocities, as measured
at the ACE satellite, averaged 350 km/s. The Bz component of the
interplanetary field did not vary much beyond +/- 4nT through the
period. A change in magnetic field vector from a positive (away) to
a negative (toward) orientation was observed at about 19/1800Z.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be at predominately quiet levels for the next three days
(20 – 22 March).
III. Event Probabilities 20 Mar-22 Mar
Class M 01/10/20
Class X 01/01/01
Proton 01/01/01
PCAF green
IV. Penticton 10.7 cm Flux
Observed 19 Mar 089
Predicted 20 Mar-22 Mar 090/095/100
90 Day Mean 19 Mar 094
V. Geomagnetic A Indices
Observed Afr/Ap 18 Mar 002/002
Estimated Afr/Ap 19 Mar 003/003
Predicted Afr/Ap 20 Mar-22 Mar 005/005-005/005-005/005
VI. Geomagnetic Activity Probabilities 20 Mar-22 Mar
A. Middle Latitudes
Active 10/10/10
Minor storm 01/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor storm 01/01/01
Major-severe storm 01/01/01