NOAA SEC Report of Solar-Geophysical Activity 12 Aug 2001
:Product: Report of Solar-Geophysical Activity
:Issued: 2001 Aug 12 2200 UT
# Prepared jointly by the U.S. Dept. of Commerce, NOAA,
#Space Environment Center and the U.S. Air Force.
#
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 224 Issued at 2200Z on 12 Aug 2001
IA. Analysis of Solar Active Regions and Activity from 11/2100Z
to 12/2100Z: Solar activity was low. Occasional C-class flares were
observed through the period. Two new regions were numbered today as
Regions 9577 (N16W15) and 9578 (S10W11).
IB. Solar Activity Forecast: Solar activity is expected to be low.
An isolated M-class event is possible.
IIA. Geophysical Activity Summary 11/2100Z to 12/2100Z:
The geomagnetic field was quiet to minor storm conditions. A shock
passed the ACE spacecraft at 12/1050 UTC and created a sudden
impulse of 23 nt on the Boulder magnetometer at 12/1136 UTC. Solar
wind velocity increased from 336 km/s to 406 km/s and density jumped
from 6 p/cc to 35 p/cc. This shock is believed related to the
partial halo coronal mass ejection observed on 09 August.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be active to minor storm conditions for 13 August due to
the CME mentioned in IIA. Quiet to unsettled conditions should
prevail on 14 and 15 August.
III. Event Probabilities 13 Aug-15 Aug
Class M 30/30/30
Class X 05/05/05
Proton 01/01/01
PCAF green
IV. Penticton 10.7 cm Flux
Observed 12 Aug 160
Predicted 13 Aug-15 Aug 155/150/145
90 Day Mean 12 Aug 151
V. Geomagnetic A Indices
Observed Afr/Ap 11 Aug 002/006
Estimated Afr/Ap 12 Aug 015/020
Predicted Afr/Ap 13 Aug-15 Aug 030/030-010/015-010/010
VI. Geomagnetic Activity Probabilities 13 Aug-15 Aug
A. Middle Latitudes
Active 25/15/15
Minor storm 15/05/05
Major-severe storm 10/01/01
B. High Latitudes
Active 30/20/20
Minor storm 20/10/05
Major-severe storm 15/05/01