Daily Report

(last updated 18 Aug 2017 23:50 UT)

SUBJ: SWS DAILY SOLAR AND GEOPHYSICAL REPORT ISSUED AT 2330UT/18 AUGUST 2017 BY Space Weather Services FROM THE AUSTRALIAN SPACE FORECAST CENTRE SUMMARY FOR 18 AUGUST AND FORECAST FOR 19 AUGUST - 21 AUGUST STATUS INDICATORS SOL:GREEN MAG:** YELLOW ** ION: GREEN ----------------------------------------------------------- 1A. SOLAR SUMMARY Activity 18 Aug: Low Flares: none. Observed 10.7 cm flux/Equivalent Sunspot Number for 18 Aug: 80/20 1B. SOLAR FORECAST 19 Aug 20 Aug 21 Aug Activity Very low to low Very low to low Very low to low Fadeouts None expected None expected None expected 10.7cm/SSN 82/23 84/26 85/27 COMMENT: Solar activity was Low over the last 24 hours. There were two notable C-class flares observed with a C4.4 event at 2002UT that appears to have originated from the west limb and a C2.9 event from region 2671 (N12E22). Region 2671 remains the only active region on the visible disk. No Earth-directed CMEs were observed in the available LASCO imagery during the last 24 hours. Solar wind speed remains elevated due to the influence of a recurrent coronal hole high speed solar wind stream and ranged between 525km/s and 661km/s over the UT day. The north-south component of IMF, Bz fluctuated between -7nT and +6nT with some minor sustained southward periods throughout the UT day. Solar wind speeds are expected to remain elevated for the next 2-3 days. Very Low to Low solar activity is expected over the next three days with further C-class events possible and slight chance of M-class activity on 19Aug-20Aug. ----------------------------------------------------------- 2A. MAGNETIC SUMMARY Geomagnetic field for Australian Region 18 Aug: Quiet to Unsettled Estimated Indices 18 Aug : A K Australian Region 12 33223332 Cocos Island 10 22223332 Darwin 12 33223332 Townsville 13 33323332 Learmonth 13 33223342 Alice Springs 12 32223342 Norfolk Island 11 33223232 Culgoora 12 33233232 Gingin 12 32223342 Camden 13 33233332 Canberra 9 22233231 Launceston 18 33334343 Hobart 16 33234342 Estimated Antarctic Regional K Indices 18 Aug : Macquarie Island 31 33356452 Casey 33 44333373 Mawson 34 45444455 Davis 39 43433475 Observed Regional daily pc3 Indices 18 Aug : Darwin 0 (Quiet) Townsville 0 (Quiet) Learmonth 0 (Quiet) Alice Springs 0 (Quiet) Gingin 56 (Unsettled) Canberra 45 (Unsettled) Melbourne NA Pc3 pulsations are high frequency (10-45 second period) variations of the Earths magnetic field. Daily pc3-indices are the daily sum of 20 minute pc3-indices for that station and have been shown to be well correlated with rejection of high resolution aeromagnetic survey flight-line data. NOTE: Indices may have been generated from data obtained in cooperation with the following organisations: Geoscience Australia, University of Newcastle Space Physics Group, Australian Government Antarctic Division and International Center for Space Weather Science and Education, Japan. Estimated AFr/Ap Indices 18 Aug : A Fredericksburg 16 Planetary 22 Observed AFr/Ap Indices 17 Aug : A K Fredericksburg 20 Planetary 28 3255 5443 2B. MAGNETIC FORECAST Date Ap Conditions 19 Aug 16 Active 20 Aug 13 Unsettled to Active 21 Aug 11 Unsettled COMMENT: Quiet to Unsettled geomagnetic activity with isolated Active periods observed across the Australian region over the past 24 hours. Geomagnetic activity is expected to be Unsettled to Active for 19Aug-20Aug due to continued coronal hole effects. A decline in geomagnetic activity is expected on 21Aug to Unsettled to Quiet conditions due to diminishing influence of the coronal hole. ----------------------------------------------------------- 3A. GLOBAL HF PROPAGATION SUMMARY Latitude Band Date Low Middle High 18 Aug Normal Normal-fair Fair PCA Event : No event. 3B. GLOBAL HF PROPAGATION FORECAST Latitude Band Date Low Middle High 19 Aug Normal Normal-fair Fair 20 Aug Normal Normal Normal-fair 21 Aug Normal Normal Normal-fair COMMENT: Variable HF conditions over the last 24 hours with minor to moderate MUF enhancement and depressions for Low to Mid latitudes. Disturbed conditions for High latitudes. Mild to moderate MUF depressions and degradations in HF conditions may be expected on 19Aug-20Aug. Improved HF conditions expected from 21Aug. ----------------------------------------------------------- 4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY Date T index 18 Aug 11 Observed Australian Regional MUFs Cocos Island Region: Depressed by 15% during local day. No data available during local night. Niue Island Region: Enhanced by 15% during local day. Near predicted monthly values during local night. Northern Australian Region: Depressed by 15% during local day. Near predicted monthly values during local night. Southern Australian Region: Near predicted monthly values during local day. Enhanced by 25% during local night. Antarctic Region (Casey/Scott Base/Davis/Mawson): Near predicted monthly values over the UT day. Monthly T index: Month T index Jul 10 Aug 6 Sep 5 4B. AUSTRALIAN REGION IONOSPHERIC FORECAST Date T index MUFs 19 Aug 10 Near predicted monthly values/depressed 10 to 30% 20 Aug 10 Near predicted monthly values/depressed 10 to 30% 21 Aug 10 Near predicted monthly values COMMENT: Variable HF conditions observed over the last 24 hours with moderate MUF enhancements and depressions over the entire region. Similar conditions are expected for the 19AUg-20Aug with possible MUF depressions and enhancements for Equatorial/Northern AUS and Southern AUS/NZ regions and disturbed ionospheric support for Antarctic regions. MUFs expected to return to monthly predicted values on 21Aug. ----------------------------------------------------------- 5. SPACE ENVIRONMENT SUMMARY GOES satellite data for 17 Aug Daily Proton Fluence >1 MeV: 4.1E+07 Daily Proton Fluence >10 MeV: 1.5E+04 Daily Electron Fluence >2 MeV: 5.30E+06 (normal fluence) Electron Fluence Daily Deep Dielectric Discharge Probability: 1% Fluence (flux accumulation over 24hrs)/ cm2-ster-day. X-ray background: A8.3 DSCOVR Satellite Solar Wind Day Averaged Data for 17 Aug Speed: 508 km/sec Density: 12.1 p/cc Temp: 267000 K Bz: 0 nT (Courtesy Space Weather Prediction Center, Boulder USA) -----------------------------------------------------------