NOAA/USAF Report of Solar-Geophysical Activity 25 July 2000

:Product: Report of Solar-Geophysical Activity
:Issued: 2000 Jul 25 2200 UT
# 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 207 ISSUED AT 2200Z ON 25 JUL 2000
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  24/2100Z
TO 25/2100Z:  SOLAR ACTIVITY HAS BEEN HIGH. REGION 9097 (N08W15),
CURRENTLY THE LARGEST GROUP ON THE DISK, PRODUCED AN M8/2B FLARE AT
0249Z WHICH WAS ACCOMPANIED BY TYPE II AND TYPE IV RADIO SWEEPS. AN
ASSOCIATED  FAINT HALO CME WAS OBSERVED BY LASCO, BEGINNING AT
0330Z. THIS REGION PRODUCED AN ADDITIONAL M-CLASS EVENT: AN M1/1B AT
1846Z. REGION 9087 (S10W80) PRODUCED AN M3/2N AT 0456Z. THE GROUP
CONTINUES TO BE A LARGE, F-TYPE REGION AS IT APPROACHES WEST LIMB.
SOME GROWTH WAS NOTED IN REGION 9090 (N15W48) BUT THE GROUP COULD
ONLY MUSTER A C6/SN FLARE AT 1241Z.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE
MODERATE, WITH REGIONS 9087, 9097, AND 9090 BEING THE MOST LIKELY
SOURCES FOR M-CLASS FLARES. THERE IS A CHANCE FOR AN ISOLATED
X-CLASS OR PROTON PRODUCING FLARE DURING THE NEXT THREE DAYS.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY 24/2100Z TO 25/2100Z:
THE GEOMAGNETIC FIELD HAS BEEN QUIET TO UNSETTLED.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE UNSETTLED WITH POSSIBLE ACTIVE PERIODS DURING THE 
NEXT 24 HOURS. AN INCREASE MAY OCCUR IF EFFECTS FROM THE CME OF 24
JULY MATERIALIZE. MOSTLY UNSETTLED CONDITIONS SHOULD PREVAIL ON 
THE SECOND DAY, AND AN INCREASE TO ACTIVE (WITH POSSIBLE MINOR-TO-
MAJOR STORM PERIODS) IS EXPECTED SOMETIME ON THE THIRD DAY. THIS 
INCREASE IS PREDICTED BECAUSE OF THE HALO CORONAL MASS EJECTION 
MENTIONED IN PART IA.
III.  EVENT PROBABILITIES 26 JUL-28 JUL
CLASS M    75/70/65
CLASS X    25/25/20
PROTON     25/25/20
PCAF       YELLOW
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           25 JUL 202
PREDICTED   26 JUL-28 JUL  190/190/190
90 DAY MEAN        25 JUL 190
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 24 JUL  004/008
ESTIMATED AFR/AP 25 JUL  007/007
PREDICTED AFR/AP 26 JUL-28 JUL  012/020-010/015-020/025
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 26 JUL-28 JUL
A.  MIDDLE LATITUDES
ACTIVE                20/20/30
MINOR STORM           10/10/25
MAJOR-SEVERE STORM    05/05/20
B.  HIGH LATITUDES
ACTIVE                30/30/30
MINOR STORM           15/15/25
MAJOR-SEVERE STORM    05/05/25