Geomagnetic Storm Forecast

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3-Day Forecast - 2023 Sep 25 1230 UTC

:Product: 3-Day Forecast
:Issued: 2023 Sep 25 1230 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
A. NOAA Geomagnetic Activity Observation and Forecast

The greatest observed 3 hr Kp over the past 24 hours was 6 (NOAA Scale
G2).
The greatest expected 3 hr Kp for Sep 25-Sep 27 2023 is 5.33 (NOAA Scale
G1).

NOAA Kp index breakdown Sep 25-Sep 27 2023

             Sep 25       Sep 26       Sep 27
00-03UT       5.33 (G1)    2.67         1.67     
03-06UT       5.00 (G1)    2.33         1.33     
06-09UT       3.33         2.00         1.67     
09-12UT       3.33         4.00         1.67     
12-15UT       3.00         4.00         1.33     
15-18UT       3.00         3.00         1.33     
18-21UT       2.33         2.00         1.33     
21-00UT       3.67         2.67         1.33     

Rationale: G1-G2 (Minor-Moderate) geomagnetic storms are expected on 25
Sep due to CME effects.

B. NOAA Solar Radiation Activity Observation and Forecast

Solar radiation, as observed by NOAA GOES-16 over the past 24 hours, was
below S-scale storm level thresholds.

Solar Radiation Storm Forecast for Sep 25-Sep 27 2023

              Sep 25  Sep 26  Sep 27
S1 or greater   25%     15%     15%

Rationale: There is a chance for S1 (Minor) solar radiation storms on 25
Sep and a slight chance over 26-27 Sep.

C. NOAA Radio Blackout Activity and Forecast

Radio blackouts reaching the R1 levels were observed over the past 24
hours. The largest was at Sep 24 2023 1500 UTC.

Radio Blackout Forecast for Sep 25-Sep 27 2023

              Sep 25        Sep 26        Sep 27
R1-R2           65%           65%           65%
R3 or greater   15%           15%           15%

Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely, with a
slight chance for R3 or greater events, over 25-27 Sep.
                        

3-Day Forecast - 2023 Sep 24 1230 UTC

:Product: 3-Day Forecast
:Issued: 2023 Sep 24 1230 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
A. NOAA Geomagnetic Activity Observation and Forecast

The greatest observed 3 hr Kp over the past 24 hours was 2 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Sep 24-Sep 26 2023 is 4.00 (below NOAA
Scale levels).

NOAA Kp index breakdown Sep 24-Sep 26 2023

             Sep 24       Sep 25       Sep 26
00-03UT       2.00         4.00         2.67     
03-06UT       2.00         3.67         2.33     
06-09UT       2.00         3.33         2.00     
09-12UT       2.00         3.00         4.00     
12-15UT       3.00         2.33         3.00     
15-18UT       2.33         2.33         2.33     
18-21UT       3.00         2.00         2.00     
21-00UT       3.67         2.33         2.67     

Rationale: G1 (Minor) geomagnetic storms are likely on 24 Sep due to
anticipated CME effects.

B. NOAA Solar Radiation Activity Observation and Forecast

Solar radiation, as observed by NOAA GOES-16 over the past 24 hours, was
below S-scale storm level thresholds.

Solar Radiation Storm Forecast for Sep 24-Sep 26 2023

              Sep 24  Sep 25  Sep 26
S1 or greater   10%     10%     10%

Rationale: No S1 (Minor) or greater solar radiation storms are expected.
No significant active region activity favorable for radiation storm
production is forecast.

C. NOAA Radio Blackout Activity and Forecast

Radio blackouts reaching the R1 levels were observed over the past 24
hours. The largest was at Sep 24 2023 0328 UTC.

Radio Blackout Forecast for Sep 24-Sep 26 2023

              Sep 24        Sep 25        Sep 26
R1-R2           65%           65%           65%
R3 or greater   15%           15%           15%

Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely over 24-26
Sep.
                        

3-Day Forecast - 2023 Sep 23 1230 UTC

:Product: 3-Day Forecast
:Issued: 2023 Sep 23 1230 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
A. NOAA Geomagnetic Activity Observation and Forecast

The greatest observed 3 hr Kp over the past 24 hours was 3 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Sep 23-Sep 25 2023 is 5.00 (NOAA Scale
G1).

NOAA Kp index breakdown Sep 23-Sep 25 2023

             Sep 23       Sep 24       Sep 25
00-03UT       3.00         5.00 (G1)    4.00     
03-06UT       2.67         4.33         3.67     
06-09UT       2.00         3.67         3.33     
09-12UT       2.67         3.00         3.00     
12-15UT       3.00         2.33         2.33     
15-18UT       3.00         3.00         2.33     
18-21UT       4.00         3.00         2.00     
21-00UT       5.00 (G1)    3.33         2.33     

Rationale: G1 (Minor) geomagnetic storms are likely late on 23 Sep and
early on 24 Sep due to the anticipated arrival of multiple CMEs.

B. NOAA Solar Radiation Activity Observation and Forecast

Solar radiation, as observed by NOAA GOES-16 over the past 24 hours, was
below S-scale storm level thresholds.

Solar Radiation Storm Forecast for Sep 23-Sep 25 2023

              Sep 23  Sep 24  Sep 25
S1 or greater   10%     10%     10%

Rationale: There is a slight chance for an S1 (Minor) solar radiation
storm on 23-25 Sep.

C. NOAA Radio Blackout Activity and Forecast

Radio blackouts reaching the R1 levels were observed over the past 24
hours. The largest was at Sep 22 2023 2300 UTC.

Radio Blackout Forecast for Sep 23-Sep 25 2023

              Sep 23        Sep 24        Sep 25
R1-R2           60%           60%           60%
R3 or greater   15%           15%           15%

Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely, with a
slight chance for R3 or greater events, over 23-25 Sep.
                        

3-Day Forecast - 2023 Sep 22 1230 UTC

:Product: 3-Day Forecast
:Issued: 2023 Sep 22 1230 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
A. NOAA Geomagnetic Activity Observation and Forecast

The greatest observed 3 hr Kp over the past 24 hours was 3 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Sep 22-Sep 24 2023 is 5.00 (NOAA Scale
G1).

NOAA Kp index breakdown Sep 22-Sep 24 2023

             Sep 22       Sep 23       Sep 24
00-03UT       2.00         3.67         5.00 (G1)
03-06UT       1.33         3.00         4.33     
06-09UT       2.67         2.67         3.67     
09-12UT       2.33         2.67         3.00     
12-15UT       3.00         2.67         2.33     
15-18UT       4.00         3.67         3.00     
18-21UT       3.00         4.33         3.00     
21-00UT       4.00         5.00 (G1)    3.33     

Rationale: The geomagnetic field is expected to be at mostly unsettled
to active levels on 22 Sep due to negative polarity CH HSS onset. G1
(Minor) geomagnetic storming is likely 23-24 Sep due to first shock and
glancing influences from the 20 Sep CME followed by the arrival of the
21 Sep CME by late on the 24th.

B. NOAA Solar Radiation Activity Observation and Forecast

Solar radiation, as observed by NOAA GOES-16 over the past 24 hours, was
below S-scale storm level thresholds.

Solar Radiation Storm Forecast for Sep 22-Sep 24 2023

              Sep 22  Sep 23  Sep 24
S1 or greater    5%      5%      5%

Rationale: No S1 (Minor) or greater solar radiation storms are expected.
No significant active region activity favorable for radiation storm
production is forecast.

C. NOAA Radio Blackout Activity and Forecast

Radio blackouts reaching the R2 levels were observed over the past 24
hours. The largest was at Sep 21 2023 1254 UTC.

Radio Blackout Forecast for Sep 22-Sep 24 2023

              Sep 22        Sep 23        Sep 24
R1-R2           55%           55%           55%
R3 or greater   10%           10%           10%

Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely, and there
is a slight chance R3 (Strong) or greater radio blackouts over 22-24
Sep.
                        

3-Day Forecast - 2023 Sep 21 1230 UTC

:Product: 3-Day Forecast
:Issued: 2023 Sep 21 1230 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
A. NOAA Geomagnetic Activity Observation and Forecast

The greatest observed 3 hr Kp over the past 24 hours was 4 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Sep 21-Sep 23 2023 is 4.00 (below NOAA
Scale levels).

NOAA Kp index breakdown Sep 21-Sep 23 2023

             Sep 21       Sep 22       Sep 23
00-03UT       2.67         1.33         3.67     
03-06UT       2.67         2.00         3.00     
06-09UT       2.33         2.00         2.67     
09-12UT       1.67         3.00         2.67     
12-15UT       2.00         3.00         2.00     
15-18UT       1.33         4.00         2.00     
18-21UT       1.33         3.00         2.67     
21-00UT       2.00         4.00         2.67     

Rationale: On 22 Sep, influence from a negative polarity coronal
hole is likely to increase geomagnetic activity levels, providing a
chance for G1 (Minor) storming periods.

B. NOAA Solar Radiation Activity Observation and Forecast

Solar radiation, as observed by NOAA GOES-16 over the past 24 hours, was
below S-scale storm level thresholds.

Solar Radiation Storm Forecast for Sep 21-Sep 23 2023

              Sep 21  Sep 22  Sep 23
S1 or greater    5%      5%      5%

Rationale: No S1 (Minor) or greater solar radiation storms are expected.
No significant active region activity favorable for radiation storm
production is forecast.

C. NOAA Radio Blackout Activity and Forecast

Radio blackouts reaching the R2 levels were observed over the past 24
hours. The largest was at Sep 20 2023 1419 UTC.

Radio Blackout Forecast for Sep 21-Sep 23 2023

              Sep 21        Sep 22        Sep 23
R1-R2           55%           55%           55%
R3 or greater    5%            5%            5%

Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely over 21-23
Sep due mainly to the increased magnetic complexity of Region 3435.
                        

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