Joint USAF/NOAA Report of Solar and Geophysical Activity 6 April 2011

Product: Report of Solar-Geophysical Activity
:Issued: 2011 Apr 06 2220 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
:::::::::: CORRECTED COPY ::::::::::
SDF Number 096 Issued at 2200Z on 06 Apr 2011
IA. Analysis of Solar Active Regions and Activity from 05/2100Z
to 06/2100Z: Solar activity increased to low levels. A C1 flare was
observed off the east limb at 06/1807Z. Region 1184 (N16W41) showed
an increase in area and spot number. New Region 1186 (N22E58) was
numbered as an Axx spot with two spots.
IB. Solar Activity Forecast: Solar activity is expected to be very
low to low during the next three days.
IIA. Geophysical Activity Summary 05/2100Z to 06/2100Z:
The geomagnetic field was at quiet to active levels, with an isolated
minor storm period observed at mid-latitudes and major storm levels
at high latitudes. The increase in activity is due to a CME
associated with a B8/Sf flare at 02/2347Z. 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 quiet to unsettled levels, with isolated active
levels at high latitudes, on day one (07 April). Activity is
expected to decrease to predominantly quiet levels on day two (08
April). Quiet to unsettled levels are expected, with isolated active levels on day three (09 April), due to expected coronal hole high-speed stream effects.
III. Event Probabilities 07 Apr-09 Apr
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green
IV. Penticton 10.7 cm Flux
Observed 06 Apr 117
Predicted 07 Apr-09 Apr 117/117/117
90 Day Mean 06 Apr 099
V. Geomagnetic A Indices
Observed Afr/Ap 05 Apr 004/007
Estimated Afr/Ap 06 Apr 019/020
Predicted Afr/Ap 07 Apr-09 Apr 008/008-005/005-010/010
VI. Geomagnetic Activity Probabilities 07 Apr-09 Apr
A. Middle Latitudes
Active 25/15/35
Minor storm 10/01/15
Major-severe storm 01/01/01
B. High Latitudes
Active 30/20/40
Minor storm 15/05/20
Major-severe storm 01/01/05