Joint USAF/NOAA Report of Solar and Geophysical Activity 4 February 2011

:Product: Report of Solar-Geophysical Activity
:Issued: 2011 Feb 04 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 035 Issued at 2200Z on 04 Feb 2011
IA. Analysis of Solar Active Regions and Activity from 03/2100Z
to 04/2100Z: Solar activity was very low. Region 1152 (S18W01)
produced a few B-class x-ray flares during the period. Newly
numbered Region 1153 (N1518) remained stable and quiet.
IB. Solar Activity Forecast: Solar activity is expected to be
predominately very low with a chance for a C-class x-ray event for
the next 3 days (5-7 February).
IIA. Geophysical Activity Summary 03/2100Z to 04/2100Z:
The geomagnetic field was predominately quiet with an isolated
unsettled period between 04/03Z-04/06Z and an active period between
04/18Z and 04/21Z. A sudden impulse of 8 nT was observed at 04/0236Z
in association with a reverse shock behind the slow moving CME from
30 January. Solar wind speeds reached near 500 km/s and Bz was
sustained between -15 and -20 nT between 04/18Z and 04/21Z.
IIB. Geophysical Activity Forecast: The geomagnetic field is
forecast to be unsettled to active with a chance for an isolated
minor storm early, then mostly quiet to unsettled for the second
half of day 1 (5 February). Conditions are forecast to be
predominately quiet on days 2 and 3 (6-7 February) as coronal hole
effects wane.
III. Event Probabilities 05 Feb-07 Feb
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF Green
IV. Penticton 10.7 cm Flux
Observed 04 Feb 082
Predicted 05 Feb-07 Feb 082/082/082
90 Day Mean 04 Feb 084
V. Geomagnetic A Indices
Observed Afr/Ap 03 Feb 000/001
Estimated Afr/Ap 04 Feb 010/010
Predicted Afr/Ap 05 Feb-07 Feb 008/008-005/005-005/005
VI. Geomagnetic Activity Probabilities 05 Feb-07 Feb
A. Middle Latitudes
Active 40/20/10
Minor storm 25/05/01
Major-severe storm 05/01/01
B. High Latitudes
Active 50/20/10
Minor storm 20/10/01
Major-severe storm 10/01/01