:Product: 20040118RSGA.txt
:Issued: 2004 Jan 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 018 Issued at 2200Z on 18 Jan 2004
IA.  Analysis of Solar Active Regions and Activity from  17/2100Z
to 18/2100Z:  Solar activity was moderate. Region 540 (S14E02)
produced an M1/1n flare at 18/0017Z. Moderate to strong radio bursts
accompanied this flare including a 190 sfu Tenflare and a large
23,000 sfu burst on 245 MHz. A Type II radio sweep was also observed
with a shock speed of near 1000 km/s. This beta-gamma spot group has
not changed much over the past 48 hours, although some new growth
was noted in the trailer spots. Region 537 (N04W83) was quite active
this period as it approached the west limb. It produced occasional
C-class activity including a C3 flare and CME at 18/2003Z. Remaining
regions were stable.
IB.  Solar Activity Forecast:  Solar activity is expected to be low
to moderate. Moderately complex Region 540 has potential for
isolated M-class flares. Further C-class activity is expected from
Region 537 on the west limb.
IIA.  Geophysical Activity Summary 17/2100Z to 18/2100Z:
The geomagnetic field was quiet to active. A coronal hole high speed
stream continues with solar wind speed ranging from 520 to 620 km/s.
The IMF Bz was predominantly northward; however, periods of
southward Bz occurred inciting the occasional active periods. The
greater than 2 MeV electron flux at geosynchronous orbit reached
high levels again today.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to range from quiet to minor storming over the next three
days. The high speed solar wind stream in progress now is expected
to persist through 19 January and produce occasional active periods.
The M5 flare that occurred on 17 January did produce a CME, but
LASCO imagery shows that most of the ejecta is southward directed.
Some weak impacts are expected on 20 January from this CME, but the
disturbance should be limited to occasional active periods with
isolated high latitude minor storming. Quiet to unsettled levels are
expected on 21 January with isolated active periods possible.
III.  Event Probabilities 19 Jan-21 Jan
Class M    01/01/01
Class X    01/01/01
Proton     01/01/01
PCAF       Green
IV.  Penticton 10.7 cm Flux
Observed           18 Jan 120
Predicted   19 Jan-21 Jan  120/115/115
90 Day Mean        18 Jan 138
V.  Geomagnetic A Indices
Observed Afr/Ap 17 Jan  009/014
Estimated Afr/Ap 18 Jan  012/016
Predicted Afr/Ap 19 Jan-21 Jan  010/012-015/025-012/015
VI.  Geomagnetic Activity Probabilities 19 Jan-21 Jan
A.  Middle Latitudes
Active                25/30/25
Minor storm           10/15/10
Major-severe storm    05/05/05
B.  High Latitudes
Active                30/40/35
Minor storm           15/20/15
Major-severe storm    05/10/05