Joint USAF/NOAA Report of Solar and Geophysical Activity 20 May 2003

SDF Number 140 Issued at 2200Z on 20 May 2003

IA. Analysis of Solar Active Regions and Activity from 19/2100Z
to 20/2100Z: Solar activity was at low levels. Region 362 (S10E10)
produced a C1.4 flare at 1931Z. Region 362 was shown some growth
since yesterday and has increased in magnetic complexity to a
beta-gamma configuration. Region 364 (S24W40) produced three C1
flares and has shown growth in area coverage. New Region 365
(S06E68) was numbered today.

IB. Solar Activity Forecast: Solar activity is expected to be at
low levels. C-class activity is expected from Regions 362 and 364.

IIA. Geophysical Activity Summary 19/2100Z to 20/2100Z:
The geomagnetic field was at unsettled levels with one period of
quiet conditions.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be at quiet to unsettled levels.

III. Event Probabilities 21 May-23 May
Class M 10/10/15
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 20 May 124
Predicted 21 May-23 May 125/135/140
90 Day Mean 20 May 123

V. Geomagnetic A Indices
Observed Afr/Ap 19 May 009/012
Estimated Afr/Ap 20 May 012/012
Predicted Afr/Ap 21 May-23 May 010/012-010/012-010/015

VI. Geomagnetic Activity Probabilities 21 May-23 May
A. Middle Latitudes
Active 25/25/25
Minor storm 10/10/10
Major-severe storm 05/05/05
B. High Latitudes
Active 35/35/35
Minor storm 15/15/15
Major-severe storm 05/05/05