:Product: 20030318RSGA.txt
:Issued: 2003 Mar 18 2200 UTC
# 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 077 Issued at 2200Z on 18 Mar 2003
IA.  Analysis of Solar Active Regions and Activity from  17/2100Z
to 18/2100Z:  Solar activity was high. Region 314 (S16W52) produced
an X1/1B flare at 18/1208 UTC. The flare was associated with type
II/IV radio sweeps, a 1400 sfu radio burst at 2695 MHz, and an
apparent CME observed by the NASA SOHO spacecraft. This region also
produced several other smaller flares over the past 24 hours. New
Region 316 (S12E66) was numbered.
IB.  Solar Activity Forecast:  Solar activity is expected to be
moderate to high. Flare activity is expected to continue in Region
314, including the chance of another major flare.
IIA.  Geophysical Activity Summary 17/2100Z to 18/2100Z:
The geomagnetic field ranged from quiet to minor storm levels as the
coronal hole induced disturbance continued. The greater than 2 MeV
electron flux at geosynchronous orbit was high.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be at active to minor storm levels for the next 48
hours. The CME associated with the 18 March X1/1B flare may
influence activity levels on 20 March.
III.  Event Probabilities 19 Mar-21 Mar
Class M    75/75/75
Class X    10/10/10
Proton     10/10/10
PCAF       green
IV.  Penticton 10.7 cm Flux
Observed           18 Mar 118
Predicted   19 Mar-21 Mar  115/110/110
90 Day Mean        18 Mar 137
V.  Geomagnetic A Indices
Observed Afr/Ap 17 Mar  019/039
Estimated Afr/Ap 18 Mar  020/026
Predicted Afr/Ap 19 Mar-21 Mar  020/025-020/020-015/015
VI.  Geomagnetic Activity Probabilities 19 Mar-21 Mar
A.  Middle Latitudes
Active                50/50/40
Minor storm           10/10/10
Major-severe storm    05/05/01
B.  High Latitudes
Active                60/60/50
Minor storm           20/20/15
Major-severe storm    10/10/05