:Product: Weekly Highlights and Forecasts
:Issued: 1999 Nov 02 2112 UT
HIGHLIGHTS OF SOLAR AND GEOMAGNETIC ACTIVITY
25 - 31 OCTOBER 1999

SOLAR ACTIVITY RANGED FROM LOW TO MODERATE LEVELS. MODERATE LEVELS
OCCURRED DURING 25 - 27 OCTOBER WITH ISOLATED, LOW-LEVEL M-CLASS
FLARES FROM REGIONS 8739 (S12, L = 167, CLASS/AREA FKC/800 ON 26
OCTOBER), 8741 (S25, L = 147, CLASS/AREA EAO/280 ON 25 OCTOBER), AND
8737 (S14, L = 235, CLASS/AREA EAO/370 ON 25 OCTOBER) (SEE THE
ENERGETIC EVENTS SUMMARY FOR OCCURRENCE TIMES). ACTIVITY DROPPED TO
LOW LEVELS ON 28 OCTOBER WITH OCCASIONAL C-CLASS SUBFLARES OBSERVED
DURING THE REST OF THE PERIOD. REGION 8739 WAS THE MOST INTERESTING
OF THE VISIBLE REGIONS DUE TO ITS  MODERATELY COMPLEX MAGNETIC
STRUCTURE. HOWEVER, THIS REGION BEGAN TO SLOWLY DECAY ON 28 OCTOBER
AND PRODUCED ISOLATED C-CLASS SUBFLARES DURING THE REST OF THE
PERIOD.

REAL-TIME SOLAR WIND DATA WERE AVAILABLE FROM THE ADVANCED
COMPOSITION EXPLORER (ACE) SPACECRAFT FOR MOST OF THE PERIOD.
CORONAL HOLE EFFECTS WERE EVIDENT ON 25 OCTOBER WITH VELOCITIES AS
HIGH AS 630 KM/SEC AND DENSITIES IN THE 01 TO 04 P/CC RANGE. THE
CORONAL HOLE EFFECTS SUBSIDED ON 26 OCTOBER. THERE WERE PERIODS OF
SUSTAINED SOUTHWARD IMF BZ OBSERVED DURING 27 OCTOBER AND DURING
28/1200 - 29/1200UT. THE 27 OCTOBER PERIOD SHOWED MAXIMUM SOUTHERLY
DEFLECTIONS TO MINUS 07 NT (GSM) WHILE THE 28 - 29 OCTOBER INTERVAL
SHOWED DEFLECTIONS TO MINUS 12 NT. THERE WERE NO REMARKABLE VELOCITY
OR DENSITY CHANGES NOTED DURING THIS PERIOD.

NO PROTON EVENTS WERE DETECTED AT GEOSYNCHRONOUS ORBIT DURING THE
PERIOD.

THE GREATER THAN 2 MEV ELECTRON FLUX DIPPED TO NORMAL TO MODERATE
LEVELS ON 29 OCTOBER, BUT WAS AT MODERATE TO HIGH LEVELS DURING THE
REST OF THE PERIOD.

THE GEOMAGNETIC FIELD WAS DISTURBED DURING 25 OCTOBER DUE TO CORONAL
HOLE EFFECTS WITH UNSETTLED TO ACTIVE LEVELS DETECTED AT MIDDLE
LATITUDES AND ACTIVE TO MAJOR STORM LEVELS AT HIGH LATITUDES. THE
FIELD WAS ALSO DISTURBED DURING 27 - 29 OCTOBER WITH UNSETTLED TO
MINOR STORM LEVELS AT MIDDLE LATITUDES AND UNSETTLED TO MAJOR STORM
LEVELS AT HIGH LATITUDES. THIS DISTURBANCE WAS CAUSED BY SUSTAINED
PERIODS OF SOUTHWARD IMF BZ.

FORECAST OF SOLAR AND GEOMAGNETIC ACTIVITY
03 - 29 NOVEMBER 1999

SOLAR ACTIVITY IS EXPECTED TO BE AT LOW TO MODERATE LEVELS.
OCCASIONAL C-CLASS FLARES ARE LIKELY. ISOLATED M-CLASS FLARES ARE
ALSO POSSIBLE THROUGHOUT THE PERIOD; ESPECIALLY AFTER 07 NOVEMBER
WHEN ACTIVE LONGITUDES ARE DUE TO RETURN.

NO SIGNIFICANT PROTON EVENTS ARE EXPECTED AT GEOSYNCHRONOUS ORBIT.

THE GREATER THAN 2 MEV ELECTRON FLUX AT GEOSYNCHRONOUS ALTITUDE IS
EXPECTED TO BE AT MODERATE TO HIGH LEVELS DURING 07 - 15 AND 20 - 23
NOVEMBER. NORMAL TO MODERATE FLUXES ARE EXPECTED DURING THE
REMAINING DAYS.

THE GEOMAGNETIC FIELD IS EXPECTED TO BE AT UNSETTLED TO ACTIVE LEVELS
DURING 06 - 13 AND 18 - 21 NOVEMBER DUE TO RECURRENT CORONAL HOLE
EFFECTS. QUIET TO UNSETTLED LEVELS ARE EXPECTED DURING THE REST OF
THE PERIOD.


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