Joint USAF/NOAA Report of Solar and Geophysical Activity 30 Apr 2012

:Product: Report of Solar-Geophysical Activity
:Issued: 2012 Apr 30 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 121 Issued at 2200Z on 30 Apr 2012
IA. Analysis of Solar Active Regions and Activity from 29/2100Z
to 30/2100Z: Solar activity has been at low levels for the past 24
hours. Before rotating off the west limb of the solar disk, Region
1465 (S18W95) produced a long duration C3 x-ray flare at 30/0738Z.
Associated with this event were both a Type II radio sweep
(estimated shock velocity of 645 km/s) and a non-Earth directed CME.
Region 1471 (S22E45) also produced multiple C-class events and
appears to be growing in sunspot area and magnetic complexity as it
rotates further into view. No new sunspot regions were numbered
today.
IB. Solar Activity Forecast: Solar activity is expected to be at
low levels for the next three days (01 – 03 May).
IIA. Geophysical Activity Summary 29/2100Z to 30/2100Z:
The geomagnetic field has been at quiet levels for the past 24 hours.
Solar wind speeds, as measured by the ACE spacecraft, remained at
nominal levels throughout the summary period.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be at quiet to unsettled levels for days one and two (01
– 02 May) as a coronal hole high speed stream moves into a
geoeffective position. A return to quiet levels is expected on day
three (03 May) as the effects of the high speed stream wane.
III. Event Probabilities 01 May-03 May
Class M 10/10/10
Class X 01/01/01
Proton 01/01/01
PCAF green
IV. Penticton 10.7 cm Flux
Observed 30 Apr 114
Predicted 01 May-03 May 115/115/115
90 Day Mean 30 Apr 112
V. Geomagnetic A Indices
Observed Afr/Ap 29 Apr 005/005
Estimated Afr/Ap 30 Apr 002/003
Predicted Afr/Ap 01 May-03 May 007/008-007/008-004/005
VI. Geomagnetic Activity Probabilities 01 May-03 May
A. Middle Latitudes
Active 15/15/10
Minor storm 05/05/01
Major-severe storm 01/01/01
B. High Latitudes
Active 25/25/15
Minor storm 10/10/05
Major-severe storm 01/01/01