[Ips-dsgr] IPS Daily Report - 28 April 01

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SUBJ: IPS DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 28/2330Z APRIL 2001 BY IPS RADIO AND SPACE SERVICES
FROM THE AUSTRALIAN SPACE FORECAST CENTRE
SUMMARY FOR 28 APRIL AND FORECAST FOR 29 APRIL - 01 MAY
STATUS INDICATORS SOL:*YELLOW*   MAG:*YELLOW*   ION: GREEN
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1A. SOLAR SUMMARY
Activity 28 Apr:  Low

Flares: none.

Observed 10.7 cm flux/Equivalent Sunspot Number for 28 Apr: 188/141

GOES satellite data for 27 Apr
       Daily Proton Fluence >1 MeV:   4.0E+06
       Daily Proton Fluence >10 MeV:  1.3E+05
       Daily Electron Fluence >2 MeV: 1.20E+07 (normal)
       X-ray background: C1.2
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.

1B. SOLAR FORECAST
             29 Apr             30 Apr             01 May
Activity     Moderate to high   Moderate to high   Moderate to high
Fadeouts     Probable           Probable           Probable
10.7cm/SSN   185/138            180/133            175/129

COMMENT: Region 9433 has the possibility of producing a proton 
flare over the next couple of days. 
A strong shock was observed in the solar wind at 0431UT on 28 Apr.
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2A. MAGNETIC SUMMARY
Geomagnetic field for Australian Region 28 Apr: Quiet to Minor Storm 

Estimated Indices 28 Apr :  A   K           
   Australian Region       26   1534 5433
      Darwin               24   1533 5434
      Townsville           26   1534 5433
      Learmonth            30   1534 6433
      Canberra             24   0533 5433
      Hobart               27   1544 5433
    
Observed Regional daily pc3 Indices 28 APR : 
      Darwin               19   (Quiet)
      Townsville           10   (Quiet)
      Learmonth             9   (Quiet)
      Canberra             32   (Quiet to unsettled)
      Hobart               31   (Quiet to unsettled)
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.

Estimated AFr/Ap Indices 28 Apr : A 
           Fredericksburg        26
           Planetary             28                         

Observed AFr/Ap Indices 27 Apr :  A   K
           Fredericksburg         3
           Planetary              6   2102 3321     


2B. MAGNETIC FORECAST 
Date      Ap    Conditions
29 Apr    20    Unsettled to active with the chance of minor 
                storm periods. 
30 Apr    15    Unsettled 
01 May    10    Quiet to unsettled 
COMMENT: IPS Geomagnetic Warning 17 was issued on 27 April and 
is current for interval 28-29 April. A strong shock was observed 
in the solar wind at 0431UT on 28 April which produced a sudden 
impulse in the geomagnetic field at 0501UT of 60-100nT across 
the Australian region. Geomagnetic activity only reached minor 
storm levels following the SI due to the lack of strong southward 
IMF. 
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3A. GLOBAL HF PROPAGATION SUMMARY
	            Latitude Band
Date        Low            Middle         High 
28 Apr      Normal         Normal         Fair-poor      
PCA Event : Began at 0440UT 28/04, Ended at 0520UT 28/04
 

3B. GLOBAL HF PROPAGATION FORECAST
	            Latitude Band
Date        Low            Middle         High 
29 Apr      Normal         Normal-Fair    Fair
30 Apr      Normal         Normal         Normal-Fair
01 May      Normal         Normal         Normal-Fair
COMMENT: Degraded HF conditions were not as significant as expected 
as geomagnetic activity did not reach anticipated levels following 
the impact of the CME at 0501UT on 28 April. 
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4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY
Date   T index
28 Apr   136

Observed Australian Regional MUFs
   Equatorial PNG Region:
      Mostly near predicted monthly values to enhanced 20%.
   Australian and New Zealand Region:
      Near predicted monthly values to enhanced 15%.
   Antarctic Region (Casey/Scott Base):
      Near predicted monthly values to 20% depressed.


Predicted Monthly T index for April: 120

4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date   T index  MUFs
29 Apr   120    depressed 5 to 15%/near predicted monthly values 
30 Apr   130    near predicted monthly values 
01 May   135    near predicted monthly values 
COMMENT: IPS HF Communications Warning 29 was issued on 27 April 
and is current for interval 27-29 April (SWFs) . Degraded HF 
conditions were not as significant as expected as geomagnetic 
activity did not reach anticipated levels following the impact 
of the CME at 0501UT on 28 April. 

IPS Radio and Space Services      | email: asfc at ips.gov.au
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