[Ips-dsgr] IPS Daily Report - 16 April 01

[rwc]

SUBJ: IPS DAILY SOLAR AND GEOPHYSICAL REPORT
ISSUED AT 16/2330Z APRIL 2001 BY IPS RADIO AND SPACE SERVICES
FROM THE AUSTRALIAN SPACE FORECAST CENTRE
SUMMARY FOR 16 APRIL AND FORECAST FOR 17 APRIL - 19 APRIL
STATUS INDICATORS SOL:** YELLOW **   MAG:** YELLOW **     ION: ** YELLOW **
-----------------------------------------------------------
1A. SOLAR SUMMARY
Activity 16 Apr:  Moderate

Flares    Max     Fadeout    Freq.  Sectors
 M1/--    0622UT  possible   lower  Mid East/Indian

Observed 10.7 cm flux/Equivalent Sunspot Number for 16 Apr: 123/76

GOES satellite data for 15 Apr
       Daily Proton Fluence >1 MeV:   3.9E+07
       Daily Proton Fluence >10 MeV:  2.1E+07
       Daily Electron Fluence >2 MeV: 2.40E+08 (moderate)
       X-ray background: B5.5
Fluence (flux accumulation over 24hrs)/ cm2-ster-day.

1B. SOLAR FORECAST
             17 Apr             18 Apr             19 Apr
Activity     Moderate           Low                Moderate
Fadeouts     Possible           None expected      Possible
10.7cm/SSN   130/84             140/94             150/105

COMMENT: Solar activity may decline after today, as 9415 rotates 
off disk. A lull in activity may then be experienced. However, 
a large previously flaring region (sec 9393) is due back around 
18 Apr and if this region returns, or if it represented an active 
solar longitude, increased flare activity may be experienced after 
this date. 
-----------------------------------------------------------
2A. MAGNETIC SUMMARY
Geomagnetic field for Australian Region 16 Apr: Quiet 

Estimated Indices 16 Apr :  A   K           
   Australian Region        4   2211 2112
      Darwin                4   2211 2111
      Townsville            4   2121 2111
      Learmonth             8   3222 22-2
      Canberra              7   3211 3112
      Hobart                6   2212 3112
    
Observed Regional daily pc3 Indices 16 APR : 
      Darwin                0   (Quiet)
      Townsville            0   (Quiet)
      Learmonth             0   (Quiet)
      Canberra              2   (Quiet)
      Hobart               10   (Quiet)
Estimated AFr/Ap Indices 16 Apr : A 
           Fredericksburg        10
           Planetary             12                         

Observed AFr/Ap Indices 15 Apr :  A   K
           Fredericksburg         9
           Planetary             13   3432 4323     


2B. MAGNETIC FORECAST 
Date      Ap    Conditions
17 Apr    18    Unsettled to active 
18 Apr    30    Active to minor storm 
19 Apr    18    active 
COMMENT: IPS Geomagnetic Warning 15 was issued on 16 April and 
is current for interval 18-19 April. Moderate geomagnetic activity 
expected on 18 April due to recent X14 flare. 
-----------------------------------------------------------
3A. GLOBAL HF PROPAGATION SUMMARY
	            Latitude Band
Date        Low            Middle         High 
16 Apr      Normal         Fair-normal    Poor-fair      
PCA Event : 10Mev Proton/PCA Event Began 15 04 2001 1405UT 
	    and is in progress (declining).

3B. GLOBAL HF PROPAGATION FORECAST
	            Latitude Band
Date        Low            Middle         High 
17 Apr      Normal         Normal-Fair    Poor(PCA)
18 Apr      Fair           Fair           Fair-Poor
19 Apr      Normal         Normal-Fair    Fair
COMMENT: High latitude HF communications continue to be effected 
by proton event. Further degradation is liekly on 18 Apr due 
to anticipated geomagnetic activity from X14 flare and recurrent
(coronal hole) factors. 
-----------------------------------------------------------
4A. AUSTRALIAN REGION IONOSPHERIC SUMMARY
Date   T index
16 Apr   132

Observed Australian Regional MUFs
   Equatorial PNG Region:
      Near predicted monthly values.
   Northern Australian Region:
      Near predicted monthly values.
   Southern Australian and New Zealand Region:
      Near predicted monthly values.
   Antarctic Region (Casey/Scott Base):
      Near predicted monthly values over the UT day.
      Absorption observed.

Predicted Monthly T index for April: 120
4B. AUSTRALIAN REGION IONOSPHERIC FORECAST
Date   T index  MUFs
17 Apr   110    near predicted monthly values 
18 Apr    85    near predicted monthly values/depressed 10-20% 
19 Apr    90    depressed 10 to 15%/near predicted monthly values 
COMMENT: IPS HF Communications Warning 26 was issued on 16 April 
and is current for interval 18-19 April. Degraded HF conditions 
expected late on 18 April due to anticipated geomagnetic activity 
from X14 flare. Effects are expected to be confined to mid to 
high latitudes (southern Aus/NZ region). 

IPS Radio and Space Services      | email: asfc at ips.gov.au
PO Box 1386                       | WWW: http://www.ips.gov.au/asfc
Haymarket NSW 1240  AUSTRALIA     | FTP: ftp://ftp.ips.gov.au/users/asfc/ 
tel: +61 2 9213 8010              | fax: +61 2 9213 8060