:Product: Weekly Highlights and Forecasts
:Issued: 2003 Feb 25 2212 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Environment Center
# Product description and SEC contact on the Web
# http://www.sec.noaa.gov/weekly.html
#
#                Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic Activity
17 - 23 February 2003

Solar Activity was at very low to low levels.  The period began with
low levels on 17 February and very low levels on 18 February.  
Early on 18 February, there was a forty-seven degree filament
eruption off the northwest quadrant at 0125 UTC.   Activity
increased to low levels on 19 – 22 February.  During this time,
Region 290 (N17, L=331, class/area/mag. Eki/360/Bg on 21 February)
exhibited growth in area and increased in magnetic complexity to a
beta-gamma configuration.  Activity from Region 290 consisted of
numerous B and C-class flares with the largest a C5/Sf flare on 22
February at 0929 UTC.  Region 290 entered a gradual decay phase on
22 February.  Activity on 23 February was at very low levels with
only minor B-class flare observed.

Solar wind data were available from the NASA Advanced Composition
Explorer (ACE) spacecraft for most of the summary period.   Late on
17 February, a transient passed the NASA/ACE spacecraft.  Solar wind
speed increased to over 700 km/s and total IMF reached peak values
near 20 nT.  Very structured, but declining solar wind parameters
persisted through 18 - 19 February with solar wind speed tailing off
to near 500 km/s and Bz sustained northward.  The solar wind
transitioned into a high-speed stream on 20 February with solar wind
speed exceeding 700 km/s.

There were no greater than 10 MeV proton events at geo-synchronous
orbit during the summary period.

The greater than 2 MeV electron flux at geo-synchronous orbit reached
high levels on 17 February and again on 22 – 23 February.

The geomagnetic field was at quiet to active levels.  Late on 17
February, a transient  passage produced increased solar wind speeds
and periods of southward Bz resulting in active levels on 18
February.  Very structured, but declining solar wind parameters
persisted through 19 February and produced quiet to active levels. 
Quiet to active levels were observed for the remainder of the
period, 20 – 23 February, due to another high speed stream that
began on 20 February.

Forecast of Solar and Geomagnetic Activity
26 February - 24 March 2003

Solar activity is expected to be at low levels with a slight chance
of moderate activity.  Region 290 has a slight potential for
isolated M-class events until it rotates beyond the west limb on 03
March.  Regions 276, 280 (S04, L=151), 282 (N10, L=128) and 284 had
increased activity as they transited the west limb and may produce
isolated M-class activity when they return to the visible disk
starting on 27 February.

No greater than 10 MeV proton events are expected during the forecast
period.

The greater than 2 MeV electron flux may reach high levels on 05 – 07
March and again on 19 – 24 March due to returning coronal holes.

The geomagnetic field is expected to be at quiet to active levels. 
Two weak coronal holes are due to return to a geo-effective
position, one on 26 – 27 February and the second on 02 – 05 March. 
A large southern coronal hole is expected to return to a
geo-effective position on 15 – 20 March and may produce quiet to
active levels with a chance of isolated minor storm conditions.


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