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

:Product: Report of Solar-Geophysical Activity
:Issued: 2011 May 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 124 Issued at 2200Z on 04 May 2011
IA. Analysis of Solar Active Regions and Activity from 03/2100Z
to 04/2100Z: Solar activity has been very low during the past 24
hours. Region 1204 (N17E13) produced a B9 x-ray event at 04/0144Z.
An eruptive filament was observed in the vicinity of Region 1205
(N14E23) at 04/1656Z. The remaining active regions were quiet and
stable.
IB. Solar Activity Forecast: Solar activity is expected to be very
low to low during days one through three (05-07 May).
IIA. Geophysical Activity Summary 03/2100Z to 04/2100Z:
The geomagnetic field has been quiet during the past 24 hours.
Observations from the ACE spacecraft indicate a steady decrease in
solar wind velocity from 600 km/s to around 425 km/s as the recent
coronal hole high speed stream subsided. The greater than 2 MeV
electron flux at geosynchronous orbit was at high levels throughout
the period.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be predominately quiet with isolated unsettled periods
for days one through three (05-07 May).
III. Event Probabilities 05 May-07 May
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green
IV. Penticton 10.7 cm Flux
Observed 04 May 107
Predicted 05 May-07 May 107/110/110
90 Day Mean 04 May 109
V. Geomagnetic A Indices
Observed Afr/Ap 03 May 008/013
Estimated Afr/Ap 04 May 006/008
Predicted Afr/Ap 05 May-07 May 005/005-005/005-007/007
VI. Geomagnetic Activity Probabilities 05 May-07 May
A. Middle Latitudes
Active 05/05/10
Minor storm 01/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 10/10/15
Minor storm 05/05/10
Major-severe storm 01/01/01