:Product: 20001110RSGA.txt
:Issued: 2000 Nov 10 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 315 Issued at 2200Z on 10 Nov 2000
IA.  Analysis of Solar Active Regions and Activity from  09/2100Z
to 10/2100Z:  Solar activity was low. Today's largest event was a
C6/1f from Region 9225 (S20W48) at 09/2122Z. There appears to be
some gradual flux emergence in this region. The rest of today's
activity consisted of a few low-level C-class events. Two new
regions were assigned today, Region 9229 (N04E70) and Region 9230
(N05W39). Both are simple and stable. There has been a noticeable
decline in activity and in background levels as regions 9218, 9212,
and 9213 rotate around the west limb.
IB.  Solar Activity Forecast:  Solar activity is expected to be low
to moderate. Regions 9218 (N21W83) and 9227 (S13E24) appear to be
the most likely sources for activity at this time.
IIA.  Geophysical Activity Summary 09/2100Z to 10/2100Z:
The geomagnetic field has been at unsettled to major storm levels.
The field was initially running at unsettled to active levels, but a
strong interplanetary shock passed the ACE spacecraft at 0604Z and
was followed promptly by a sudden impulse at 0629Z (measuring 67 nT
in Boulder), and a period of minor to major storm level activity
(i.e. K-indices of 5 and 6). The solar wind following the shock did
not exhibit strongly southward fields, and the result was a weaker
disturbance than had been expected, with a decline to active to
unsettled during the last nine hours of the period. This shock most
likely is the result of the CME associated with the M7 flare of 8
November, and the solar wind signatures are consistent with an
interpretation that the Earth received a glancing, rather than a
direct blow from the interplanetary disturbance. Event level proton
fluxes continued today at the greater than 10 MeV and 100 MeV
levels. Flux levels declined throughout the period, with current
levels (as of 10/2100Z) of 192 pfu and 1.3 pfu at 10 MeV and 100 MeV
respectively.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be mostly active during the next 24 hours, but there may
be with periods of minor to major storm levels, particularly during
local nighttime hours. Active levels are expected to continue
through the second day and partway through the third day, as effects
are expected from a favorably positioned coronal hole. The greater
than 100 MeV proton event should end within a few hours, but the
greater than 10 MeV event is likely to continue into the third day.
III.  Event Probabilities 11 Nov-13 Nov
Class M    35/35/35
Class X    05/05/05
Proton     99/99/70
PCAF       in progress
IV.  Penticton 10.7 cm Flux
Observed           10 Nov 153
Predicted   11 Nov-13 Nov  150/150/150
90 Day Mean        10 Nov 173
V.  Geomagnetic A Indices
Observed Afr/Ap 09 Nov  010/011
Estimated Afr/Ap 10 Nov  030/040
Predicted Afr/Ap 11 Nov-13 Nov  025/035-020/020-015/020
VI.  Geomagnetic Activity Probabilities 11 Nov-13 Nov
A.  Middle Latitudes
Active                40/40/30
Minor storm           30/30/20
Major-severe storm    10/10/10
B.  High Latitudes
Active                15/15/25
Minor storm           50/50/40
Major-severe storm    20/20/15