Status Report

Joint USAF/NOAA Report of Solar and Geophysical Activity 18 Jul 2002

By SpaceRef Editor
July 18, 2002
Filed under , ,

:Product: Report of Solar-Geophysical Activity
:Issued: 2002 Jul 18 2210 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 199 Issued at 2200Z on 18 Jul 2002
IA. Analysis of Solar Active Regions and Activity from 17/2100Z
to 18/2100Z: Solar activity was at high levels. Region 30 (N18W38)
produced an X1/2b flare at 18/0744 UTC with an associated Type II,
Type IV, and discrete frequency radio bursts. SOHO/LASCO imagery
indicates a faint full halo CME. Region 30 continues its gradual
decay but retains a beta-gamma-delta magnetic classification.
Region 36 (S07E37) has grown to 860 millionths and 26 spots. This
large compact region did not produce any significant activity during
the last 24 hours.
IB. Solar Activity Forecast: Solar activity is expected to be
moderate. M-Class activity is expected from Region 30 and Region
36. There is also the possibility of isolated X-class activity from
these regions.
IIA. Geophysical Activity Summary 17/2100Z to 18/2100Z:
The geomagnetic field was at quiet to unsettled levels. The PCA
event that began on 16/2215 UTC ended at 18/0300 UTC with a peak
absorption observed on the Thule 30 MHz riometer of 6 Db at 17/1600
UTC. The greater than 10 MeV proton event that began on 16/1750 UTC
ended at 18/1550 UTC, peak value reached 234 pfu at 17/1600 UTC.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet to active. A CME shock from the X1 event on
18/0744 UTC is expected to arrive early on day two of the forecast
III. Event Probabilities 19 Jul-21 Jul
Class M 75/75/75
Class X 20/20/20
Proton 50/15/15
PCAF Yellow
IV. Penticton 10.7 cm Flux
Observed 18 Jul 181
Predicted 19 Jul-21 Jul 185/185/190
90 Day Mean 18 Jul 161
V. Geomagnetic A Indices
Observed Afr/Ap 17 Jul 015/018
Estimated Afr/Ap 18 Jul 008/010
Predicted Afr/Ap 19 Jul-21 Jul 015/020-015/015-012/020
VI. Geomagnetic Activity Probabilities 19 Jul-21 Jul
A. Middle Latitudes
Active 25/35/25
Minor storm 10/15/10
Major-severe storm 01/05/01
B. High Latitudes
Active 30/40/30
Minor storm 15/20/15
Major-severe storm 05/05/05

SpaceRef staff editor.