Daily Report

(last updated 21 Jun 2021 23:30 UT)

SUBJ: SWS DAILY SOLAR AND GEOPHYSICAL REPORT ISSUED AT 2330UT/21 JUNE 2021 BY Space Weather Services FROM THE AUSTRALIAN SPACE FORECAST CENTRE SUMMARY FOR 21 JUNE AND FORECAST FOR 22 JUNE - 24 JUNE STATUS INDICATORS SOL:GREEN MAG:GREEN ION: GREEN ----------------------------------------------------------- 1A. SOLAR SUMMARY Activity 21 Jun: Very low Flares: none. Observed 10.7 cm flux/Equivalent Sunspot Number for 21 Jun: 79/19 1B. SOLAR FORECAST 22 Jun 23 Jun 24 Jun Activity Very low Very low Very low Fadeouts None expected None expected None expected 10.7cm/SSN 80/20 80/20 80/20 COMMENT: Solar activity was very low on UT day 21 June. Currently there is one numbered region on the visible disk, AR 2833 (N25W23). Two active regions are about to rotate over the eastern limb. There was a DSF observed in H-alpha and SDO images around 21/10 UT near N12W35. There was also a weak westward CME observed in Lasco and Stereo-A coronagraph images around 21/1348 UT that may be associated with this DSF, unlikely to have any earth directed component. No other CMEs were observed in the available coronagraph images. A large filament in the NW quadrant is monitored for any eruption. Solar activity is expected to be very low to on UT days 22-24 June with a slight chance of a C-class flare. On 21 June, the solar wind speed was between 330 km/s and 390 km/s. The IMF (Bt) peaked at 5 nT and the north-south IMF component (Bz) range was +/-3 nT. The solar wind speed is expected to be near background levels on UT day 22 June. A northern polar coronal hole extension plus a small southern hemisphere coronal hole may become geoeffective from UT day 23 June, elevating the solar wind speed to slightly enhanced levels through UT day 24 June, ----------------------------------------------------------- 2A. MAGNETIC SUMMARY Geomagnetic field for Australian Region 21 Jun: Quiet Estimated Indices 21 Jun : A K Australian Region 0 10001000 Cocos Island 0 00010000 Darwin 1 10101001 Townsville 2 21001001 Learmonth 0 10001000 Alice Springs 0 00001000 Gingin 0 00001010 Canberra 0 00001000 Hobart 0 00001100 Estimated Antarctic Regional K Indices 21 Jun : Macquarie Island 0 00000000 Casey 3 11002212 Mawson 8 32110034 Observed Regional daily pc3 Indices 21 Jun : Darwin 0 (Quiet) Townsville 0 (Quiet) Learmonth 0 (Quiet) Alice Springs 0 (Quiet) Gingin 0 (Quiet) Canberra 0 (Quiet) Hobart 0 (Quiet) 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 21 Jun : A Fredericksburg 4 Planetary 4 Observed AFr/Ap Indices 20 Jun : A K Fredericksburg 4 Planetary 3 0100 1013 2B. MAGNETIC FORECAST Date Ap Conditions 22 Jun 5 Quiet 23 Jun 10 Quiet to Unsettled 24 Jun 10 Quiet to Unsettled COMMENT: Geomagnetic conditions in the Australian region were quiet on UT day 21 June. Isolated unsettled and active periods observed in the Antarctic region. Global geomagnetic conditions are expected to be mostly quiet on UT day 22 June. Unsettled conditions are possible on UT days 23-24 June due to weak coronal hole effects. ----------------------------------------------------------- 3A. GLOBAL HF PROPAGATION SUMMARY Latitude Band Date Low Middle High 21 Jun Normal-fair Normal Normal PCA Event : No event. 3B. GLOBAL HF PROPAGATION FORECAST Latitude Band Date Low Middle High 22 Jun Normal-fair Normal Normal 23 Jun Normal Normal-fair Normal-fair 24 Jun Normal Normal-fair Normal-fair COMMENT: Mostly normal HF propagation conditions are expected on UT days 22-24 June. ----------------------------------------------------------- 4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY Date T index 21 Jun 9 Observed Australian Regional MUFs Cocos Island Region: No data available. Niue Island Region: Depressed by 20% during local day. Near predicted monthly values during local night. Depressed by 20% after local dawn. Northern Australian Region: Mostly near predicted monthly values. Southern Australian Region: Near predicted monthly values. Antarctic Region (Casey/Scott Base/Davis/Mawson): Near predicted monthly values over the UT day. Monthly T index: Month T index May 13 Jun 22 Jul 24 4B. AUSTRALIAN REGION IONOSPHERIC FORECAST Date T index MUFs 22 Jun 10 Near predicted monthly values 23 Jun 10 Near predicted monthly values 24 Jun 5 Near predicted monthly values COMMENT: MUFs in the Australian region on UT day 21 June were near predicted monthly values with some mild depressions in the Niue island region. MUFs are expected to be near predicted monthly values with some mild depressions on UT days 22-24 June. ----------------------------------------------------------- 5. SPACE ENVIRONMENT SUMMARY GOES satellite data for 20 Jun Daily Proton Fluence >1 MeV: 6.2E+04 Daily Proton Fluence >10 MeV: 4.4E+04 Daily Electron Fluence >2 MeV: 2.40E+08 (moderate fluence) Electron Fluence Daily Deep Dielectric Discharge Probability:17% Fluence (flux accumulation over 24hrs)/ cm2-ster-day. X-ray background: A4.5 DSCOVR Satellite Solar Wind Day Averaged Data for 20 Jun Speed: 420 km/sec Density: 4.9 p/cc Temp: 104000 K Bz: 1 nT (Courtesy Space Weather Prediction Center, Boulder USA) -----------------------------------------------------------