:Product: 20020719RSGA.txt :Issued: 2002 Jul 19 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 200 Issued at 2200Z on 19 Jul 2002 IA. Analysis of Solar Active Regions and Activity from 18/2100Z to 19/2100Z: Solar activity was low. The day's largest event was an unobserved C8 at 18/2317 UTC. Region 30 (N16W54) continued to produce numerous flares, but all have been small. The region retains a degree of magnetic complexity as it encompasses a large field of bright plage. Region 36 (S06E26) is still impressive in white light and h-alpha, but was unproductive. IB. Solar Activity Forecast: Solar activity is expected to be moderate. Regions 30 and 36 have the potential for M-class activity. In addition, LASCO has seen additional backside CMEs that herald the arrival of an active region on the SE limb. Old Region 17 (S18) developed as it approached W limb last rotation, and produced one X-class and 4 M-class events. It's arrival at E limb is imminent. IIA. Geophysical Activity Summary 18/2100Z to 19/2100Z: The geomagnetic field was quiet to unsettled. The solar wind has been turbulent during the past 24 hours, with at least two shocks passing ACE during the middle part of the period. A greater than 10 MeV proton event began following the first shock at 19/1050 UTC. It attained a tentative maximum of 13 pfu at 1515 UTC. Proton fluxes are currently hovering just below 10 pfu. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be unsettled to active for the next 48 hours. A CME from activity on 18 July is expected on 20 July, but is not expected to have a strong impact on the geomagnetic field. Proton fluxes may become somewhat enhanced with the shock passage. III. Event Probabilities 20 Jul-22 Jul Class M 75/75/75 Class X 20/20/20 Proton 50/50/20 PCAF yellow IV. Penticton 10.7 cm Flux Observed 19 Jul 182 Predicted 20 Jul-22 Jul 180/180/185 90 Day Mean 19 Jul 161 V. Geomagnetic A Indices Observed Afr/Ap 18 Jul 004/008 Estimated Afr/Ap 19 Jul 008/015 Predicted Afr/Ap 20 Jul-22 Jul 015/015-015/020-010/015 VI. Geomagnetic Activity Probabilities 20 Jul-22 Jul A. Middle Latitudes Active 40/40/30 Minor storm 15/15/10 Major-severe storm 05/05/05 B. High Latitudes Active 50/50/40 Minor storm 20/20/15 Major-severe storm 05/05/05