:Product: Weekly Highlights and Forecasts
:Issued: 2000 Apr 04 2112 UT
HIGHLIGHTS OF SOLAR AND GEOMAGNETIC ACTIVITY
27 MARCH - 02 APRIL 2000

SOLAR ACTIVITY RANGED FROM LOW TO HIGH LEVELS.THE PERIOD BEGAN WITH
ACTIVITY AT MODERATE LEVELS AS REGION 8926 (S10, L = 013, CLASS/AREA
DAI/090 ON 24 MARCH) PRODUCED ISOLATED M-CLASS FLARES WHICH INCLUDED
AN M1/1N AT 27/0518UT AND AN M3/SF AT 28/0137UT. AN OPTICALLY
UNCORRELATED TYPE II RADIO SWEEP OCCURRED AT 27/0646UT. ACTIVITY
DROPPED TO LOW LEVELS ON 29 MARCH WITH OCCASIONAL C-CLASS X-RAY
FLARES, MOST OF WHICH WERE OPTICALLY UNCORRELATED. ACTIVITY RETURNED
TO MODERATE LEVELS ON 30 MARCH AS REGION 8936 (S15, L = 202,
CLASS/AREA DAI/360 ON 02 APRIL) PRODUCED MULTIPLE LOW-LEVEL M-CLASS
FLARES WHICH INCLUDED AN M1/SF AT 30/1245UT, AN M3/1N AT 30/1606UT,
AND AN M2/2B AT 30/2325UT. ACTIVITY ROSE TO HIGH LEVELS ON 31 MARCH
DUE TO NUMEROUS M-CLASS FLARES FROM SEVERAL REGIONS. THE MOST FLARE
PRODUCTIVE OF THESE WAS REGION 8939 (N23, L = 194, CLASS/AREA
DAO/120 ON 02 APRIL), A SMALL, COMPACT REGION WITH A STRONG DEGREE
OF MAGNETIC MIXING. IT PRODUCED AN M4/SF AT 31/1019UT ASSOCIATED
WITH A TYPE IV RADIO SWEEP, AS WELL AS M1/SF FLARES AT 31/0755UT,
31/1318UT, AND 31/1655UT. REGION 8936, A COMPACT, MIXED-POLARITY
GROUP, SHOWED MODERATE GROWTH DURING 31 MARCH AND PRODUCED AN M1/SN
AT 31/0652UT. REGION 8925 (S18, L = 283, CLASS/AREA DKI/270 ON 27
MARCH) ADDED TO THE 31 MARCH M-CLASS TOTAL WITH AN M2/1N AT
31/1901UT. ACTIVITY DECREASED TO LOW LEVELS DURING THE LAST TWO DAYS
OF THE PERIOD WITH MOST REGIONS EITHER STABILIZED OR DECAYING.

REAL-TIME SOLAR WIND DATA WERE AVAILABLE FROM THE NASA ADVANCED
COMPOSITION EXPLORER (ACE) SPACECRAFT FOR MOST OF THE PERIOD. A
TRANSIENT SIGNATURE WAS OBSERVED ON 29 MARCH WITH AN ASSOCIATED
VELOCITY INCREASE FROM 320 TO 670 KM/SEC, A MINOR DENSITY INCREASE,
AND PERIODS OF SOUTHWARD IMF BZ WITH MAXIMUM DEFLECTIONS TO MINUS 8
NT (GSM). IMF BZ WAS GENERALLY SOUTHWARD DURING 30 - 31 MARCH WITH
MAXIMUM DEFLECTIONS TO MINUS 9 NT ALONG WITH INCREASED DENSITIES.
ANOTHER DISTURBANCE WAS DETECTED DURING 01 - 02 APRIL WITH INCREASED
VELOCITIES (PEAKS UP TO 510 KM/SEC ON 02 APRIL) ALONG WITH PERIODS
OF SOUTHWARD BZ TO MINUS 11 NT.

THERE WERE NO PROTON EVENTS OR ENHANCEMENTS AT GEOSYNCHRONOUS ORBIT.

THE GREATER THAN 2 MEV ELECTRON FLUX AT GEOSYNCHRONOUS ORBIT WAS AT
NORMAL TO MODERATE LEVELS.

THE GEOMAGNETIC FIELD WAS MILDLY DISTURBED DURING THE LATTER HALF OF
29 MARCH WITH UNSETTLED TO ACTIVE LEVELS DETECTED GLOBALLY AND BRIEF
MINOR STORM PERIODS AT HIGH LATITUDES. ACTIVITY SUBSIDED TO MOSTLY
QUIET TO UNSETTLED LEVELS DURING 30 MARCH. ACTIVITY INCREASED DURING
THE FIRST HALF OF 31 MARCH WITH ACTIVE TO MINOR STORM LEVELS
DETECTED, THEN DECLINED TO QUIET TO UNSETTLED LEVELS FOR THE
REMAINDER OF THE DAY. ACTIVITY INCREASED TO UNSETTLED TO ACTIVE
LEVELS DURING 01/1800 - 02/0900UT FOLLOWED BY A RETURN TO QUIET TO
UNSETTLED LEVELS.

FORECAST OF SOLAR AND GEOMAGNETIC ACTIVITY
05 APRIL - 01 MAY 2000

SOLAR ACTIVITY IS EXPECTED TO VARY BETWEEN LOW AND MODERATE LEVELS
WITH ISOLATED LOW-LEVEL M-CLASS FLARES LIKELY. THERE WILL ALSO BE A
SLIGHT CHANCE FOR ISOLATED MAJOR FLARE ACTIVITY SOMETIME DURING THE
PERIOD DUE TO THE RETURN OF PREVIOUSLY ACTIVE LONGITUDES.

THERE WILL BE A SLIGHT CHANCE FOR A PROTON FLUX EVENT AT
GEOSYNCHRONOUS ORBIT SOMETIME DURING THE PERIOD.

THE GREATER THAN 2 MEV ELECTRON FLUX AT GEOSYNCHRONOUS ORBIT IS
EXPECTED TO BE AT NORMAL TO MODERATE LEVELS DURING MOST OF THE
PERIOD.

BARRING AN EARTH-DIRECTED CORONAL MASS EJECTION (CME), GEOMAGNETIC
FIELD ACTIVITY IS EXPECTED TO BE AT QUIET TO UNSETTLED LEVELS FOR
MOST OF THE PERIOD.

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