noaa/USAF Report of Solar-Geophysical Activity 26 July 2000

:Product: Report of Solar-Geophysical Activity
:Issued: 2000 Jul 26 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 208 ISSUED AT 2200Z ON 26 JUL 2000
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  25/2100Z
TO 26/2100Z:  SOLAR ACTIVITY HAS BEEN MODERATE.  AN OPTICALLY
UNCORRELATED M1 FLARE OCCURRED AT 26/0743Z, MOST LIKELY FROM REGION
9087 BEHIND THE WEST LIMB (S11W94).  A SINGLE C5/SF FLARE WAS
OBSERVED AT 26/1807Z FROM REGION 9097 (N07W27), WHICH REMAINS THE
LARGEST REGION ON THE DISK. NUMEROUS C-CLASS FLARES WERE ALSO
OBSERVED FROM REGION 9090 (N14W61) THROUGHOUT THE PERIOD.  NEW
REGION 9103 (N08E28) WAS NUMBERED TODAY.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE
MODERATE.  REGIONS 9090 AND 9097 ARE THE MOST LIKELY SOURCES FOR
M-CLASS ACTIVITY.  A MODEST CHANCE FOR ISOLATED X-CLASS OR PROTON
PRODUCING FLARES ALSO EXISTS FOR THE NEXT THREE DAYS.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY 25/2100Z TO 26/2100Z:
THE GEOMAGNETIC FIELD RANGED FROM QUIET TO MINOR STORM LEVELS
THROUGHOUT THE PERIOD.  TWO WEAK SHOCK PASSAGES AT APPROXIMATELY
0300Z AND 1800Z CONTRIBUTED TO PERIODS OF ACTIVE AND MINOR STORM
LEVELS IN THE GEOMAGNETIC FIELD.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE UNSETTLED TO ACTIVE, WITH AN INCREASED CHANCE OF
ISOLATED MINOR STORM LEVELS ON THE SECOND AND THIRD DAY IN
CONJUNCTION WITH THE EXPECTED ARRIVAL OF THE CME ACTIVITY FROM
25/0249Z.
III.  EVENT PROBABILITIES 27 JUL-29 JUL
CLASS M    75/75/75
CLASS X    20/20/20
PROTON     20/20/20
PCAF       YELLOW
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           26 JUL 175
PREDICTED   27 JUL-29 JUL  170/175/170
90 DAY MEAN        26 JUL 190
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 25 JUL  004/007
ESTIMATED AFR/AP 26 JUL  016/016
PREDICTED AFR/AP 27 JUL-29 JUL  010/012-020/025-020/020
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 27 JUL-29 JUL
A.  MIDDLE LATITUDES
ACTIVE                20/30/30
MINOR STORM           10/25/20
MAJOR-SEVERE STORM    05/20/15
B.  HIGH LATITUDES
ACTIVE                30/30/30
MINOR STORM           15/25/20
MAJOR-SEVERE STORM    05/25/20