NOAA SEC Report of Solar-Geophysical Activity 19 Nov 2001

:Product: Report of Solar-Geophysical Activity
:Issued: 2001 Nov 19 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 323 Issued at 2200Z on 19 Nov 2001
IA.  Analysis of Solar Active Regions and Activity from  18/2100Z
to 19/2100Z:  Solar activity was low. Region 9704 (S18E02) produced a
number of C-class subflares, the largest being a C4/Sf at 19/0701
UTC. This Region remains the most magnetically complex presently on
the disk.
IB.  Solar Activity Forecast:  Solar activity is expected to be low
to moderate. Region 9704 remains capable of M-class flares.
IIA.  Geophysical Activity Summary 18/2100Z to 19/2100Z:
The geomagnetic field ranged from quiet to active levels. A shock was
observed at the NASA ACE spacecraft at about 19/1735 UTC, followed
by a sudden impulse at ground magnetometers (10 nT at Boulder) at
about 19/1815 UTC. This shock is believed to be associated with a
CME which occurred on 17 November. The greater than 10 MeV proton
flux at geosynchronous orbit exceeded the 10 pfu event threshold at
19/1230 UTC. This event remains in progress with a maximum flux so
far of 20 pfu at 19/2055 UTC. This event is believed to also be
associated with the M2/1n/CME event on 17 November.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be unsettled to active for the next 24 hours becoming
quiet to unsettled by the end of the three day forecast period. The
greater than 10 MeV proton event is expected to end within the next
48 hours.
III.  Event Probabilities 20 Nov-22 Nov
Class M    50/50/50
Class X    10/10/10
Proton     95/50/10
PCAF       yellow
IV.  Penticton 10.7 cm Flux
Observed           19 Nov 191
Predicted   20 Nov-22 Nov  190/185/180
90 Day Mean        19 Nov 218
V.  Geomagnetic A Indices
Observed Afr/Ap 18 Nov  008/007
Estimated Afr/Ap 19 Nov  015/015
Predicted Afr/Ap 20 Nov-22 Nov  015/015-010/012-010/012
VI.  Geomagnetic Activity Probabilities 20 Nov-22 Nov
A.  Middle Latitudes
Active                25/20/20
Minor storm           10/05/05
Major-severe storm    05/01/01
B.  High Latitudes
Active                25/25/25
Minor storm           10/10/10
Major-severe storm    05/05/05