:Product: 20000127RSGA.txt
:Issued: 2000 Jan 27 2200 UTC
# 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 027 ISSUED AT 2200Z ON 27 JAN 2000
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  26/2100Z
TO 27/2100Z:  SOLAR ACTIVITY HAS BEEN VERY LOW. REGION 8844 (N05W60)
IS THE LARGEST GROUP ON THE DISK BUT WAS QUIET AND APPEARED TO BE IN
DECLINE. NEW REGION 8848 (S09E66) ROTATED INTO VIEW TODAY AS A
SMALL, C-TYPE GROUP, AND NEW REGION 8846 (N37E39) EMERGED AS A
SMALL, HIGH LATITUDE A-TYPE SUNSPOT GROUP.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE VERY
LOW TO LOW.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 26/2100Z TO 27/2100Z:
THE GEOMAGNETIC FIELD WAS MOSTLY QUIET UNTIL A SUDDEN IMPULSE WAS
OBSERVED AT 1455 UT. SINCE THEN CONDITIONS HAVE BEEN UNSETTLED TO
ACTIVE. A SHOCK WAS SEEN AT ACE AT 1350Z AND WAS FOLLOWED BY A HIGH
DENSITY FLOW WITH STRONGLY FLUCTUATING MAGNETIC FIELDS. SIMULTANEOUS
WITH THE SHOCK WAS A REVERSAL OF THE SPIRAL ANGLE (PHI) FROM TOWARDS
TO AWAY. AFTER 1830Z THE SOLAR WIND SPEED AND TEMPERATURE BEGAN TO
RISE CONSIDERABLY AS DENSITY BEGAN TO FALL. THESE SIGNATURES ARE
CONSISTENT WITH A STRONG, CO-ROTATING INTERACTION REGION WHICH MOST
LIKELY WILL BE FOLLOWED BY A HIGH SPEED CORONAL HOLE WIND STREAM.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE MOSTLY ACTIVE FOR THE NEXT TWO DAYS, WITH PERIODS OF
MINOR STORM LEVELS DURING THE FIRST PART OF DAY ONE. CONDITIONS WILL
DECLINE TO UNSETTLED LEVELS WITH OCCASIONAL ACTIVE PERIODS BY THE
THIRD DAY.
III.  EVENT PROBABILITIES 28 JAN-30 JAN
CLASS M    10/10/10
CLASS X    01/01/01
PROTON     01/01/01
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           27 JAN 132
PREDICTED   28 JAN-30 JAN  130/130/125
90 DAY MEAN        27 JAN   175
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 26 JAN  007/007
ESTIMATED AFR/AP 27 JAN  015/018
PREDICTED AFR/AP 28 JAN-30 JAN  020/025-020/025-015/018
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 28 JAN-30 JAN
A.  MIDDLE LATITUDES
ACTIVE                50/50/40
MINOR STORM           25/20/15
MAJOR-SEVERE STORM    15/10/05
B.  HIGH LATITUDES
ACTIVE                40/40/40
MINOR STORM           30/25/15
MAJOR-SEVERE STORM    15/10/05