Geomagnetic Storm Forecast

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3-Day Forecast - 2023 Sep 18 1230 UTC

:Product: 3-Day Forecast
:Issued: 2023 Sep 18 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 5 (NOAA Scale
G1).
The greatest expected 3 hr Kp for Sep 18-Sep 20 2023 is 6.00 (NOAA Scale
G2).

NOAA Kp index breakdown Sep 18-Sep 20 2023

             Sep 18       Sep 19       Sep 20
00-03UT       4.67 (G1)    3.00         3.33     
03-06UT       4.00         5.00 (G1)    4.00     
06-09UT       2.67         5.00 (G1)    3.00     
09-12UT       2.00         6.00 (G2)    2.33     
12-15UT       1.00         4.00         2.00     
15-18UT       2.00         3.00         2.00     
18-21UT       1.00         3.00         3.33     
21-00UT       3.00         4.33         3.33     

Rationale: G1-G2 (Minor-Moderate) levels are likely on 19 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 18-Sep 20 2023

              Sep 18  Sep 19  Sep 20
S1 or greater   10%     10%      1%

Rationale: There is a slight chance for an S1 (Minor) solar radiation
storm on 18-19 Sep.

C. NOAA Radio Blackout Activity and Forecast

No radio blackouts were observed over the past 24 hours.

Radio Blackout Forecast for Sep 18-Sep 20 2023

              Sep 18        Sep 19        Sep 20
R1-R2           20%           20%           20%
R3 or greater    1%            1%            1%

Rationale: A slight chance for M-class flares (R1-R2/Minor-Moderate)
exists on 18-20 Sep.
                        

3-Day Forecast - 2023 Sep 17 1230 UTC

:Product: 3-Day Forecast
:Issued: 2023 Sep 17 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 17-Sep 19 2023 is 6.00 (NOAA Scale
G2).

NOAA Kp index breakdown Sep 17-Sep 19 2023

             Sep 17       Sep 18       Sep 19
00-03UT       3.33         3.00         3.00     
03-06UT       3.67         2.00         6.00 (G2)
06-09UT       3.00         2.00         5.33 (G1)
09-12UT       3.33         2.00         4.67 (G1)
12-15UT       2.33         1.00         3.67     
15-18UT       2.00         2.00         3.33     
18-21UT       3.00         1.00         3.00     
21-00UT       4.67 (G1)    3.00         4.33     

Rationale: G1 (Minor) geomagnetic storms are likely on 17 Sep with G1-G2
(Minor-Moderate) levels likely on 19 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 17-Sep 19 2023

              Sep 17  Sep 18  Sep 19
S1 or greater    1%      1%      1%

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

No radio blackouts were observed over the past 24 hours.

Radio Blackout Forecast for Sep 17-Sep 19 2023

              Sep 17        Sep 18        Sep 19
R1-R2           25%           25%           25%
R3 or greater    1%            1%            1%

Rationale: A chance for M-class flares (R1-R2/Minor-Moderate) exists on
17-19 Sep.
                        

3-Day Forecast - 2023 Sep 16 1230 UTC

:Product: 3-Day Forecast
:Issued: 2023 Sep 16 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 16-Sep 18 2023 is 4.67 (NOAA Scale
G1).

NOAA Kp index breakdown Sep 16-Sep 18 2023

             Sep 16       Sep 17       Sep 18
00-03UT       2.00         4.67 (G1)    3.00     
03-06UT       0.67         3.33         3.00     
06-09UT       1.00         3.67         2.00     
09-12UT       1.00         3.67         2.00     
12-15UT       1.67         3.33         1.00     
15-18UT       2.00         2.33         2.00     
18-21UT       3.00         2.67         1.00     
21-00UT       3.00         3.33         2.00     

Rationale: G1 (Minor) geomagnetic storms are likely on 17 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 16-Sep 18 2023

              Sep 16  Sep 17  Sep 18
S1 or greater   15%     15%     15%

Rationale: There is a slight chance for a greater than 10 MeV proton
event reaching the S1/Minor levels through 18 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 16 2023 0538 UTC.

Radio Blackout Forecast for Sep 16-Sep 18 2023

              Sep 16        Sep 17        Sep 18
R1-R2           55%           55%           55%
R3 or greater   10%           10%           10%

Rationale: M-class flares (R1-R2/Minor-Moderate) are likely with a
slight chance for an X-class flare (R3/Strong) on 16-18 Sep due mainly
to the flare potential of Region 3429.
                        

3-Day Forecast - 2023 Sep 15 1230 UTC

:Product: 3-Day Forecast
:Issued: 2023 Sep 15 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 15-Sep 17 2023 is 4.00 (below NOAA
Scale levels).

NOAA Kp index breakdown Sep 15-Sep 17 2023

             Sep 15       Sep 16       Sep 17
00-03UT       2.67         3.33         3.00     
03-06UT       2.00         2.33         4.00     
06-09UT       1.00         2.00         3.67     
09-12UT       0.33         1.67         3.33     
12-15UT       2.00         1.33         3.00     
15-18UT       2.67         1.33         2.00     
18-21UT       3.00         2.00         2.33     
21-00UT       3.00         2.33         2.33     

Rationale: Unsettled to active levels are likely on 17 Sep due to
potential 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 15-Sep 17 2023

              Sep 15  Sep 16  Sep 17
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 R1 levels were observed over the past 24
hours. The largest was at Sep 14 2023 2126 UTC.

Radio Blackout Forecast for Sep 15-Sep 17 2023

              Sep 15        Sep 16        Sep 17
R1-R2           35%           35%           35%
R3 or greater    5%            5%            5%

Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts
on 15-17 Sep.
                        

3-Day Forecast - 2023 Sep 01 1230 UTC

:Product: 3-Day Forecast
:Issued: 2023 Sep 01 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 01-Sep 03 2023 is 5.00 (NOAA Scale
G1).

NOAA Kp index breakdown Sep 01-Sep 03 2023

             Sep 01       Sep 02       Sep 03
00-03UT       3.00         2.67         5.00 (G1)
03-06UT       2.67         2.67         5.00 (G1)
06-09UT       2.67         2.33         4.67 (G1)
09-12UT       3.33         2.33         4.33     
12-15UT       2.33         2.00         4.00     
15-18UT       2.00         3.33         4.00     
18-21UT       2.00         3.67         4.00     
21-00UT       1.67         4.33         4.33     

Rationale: No G1 (Minor) or greater geomagnetic storms are expected.  No
significant transient or recurrent solar wind features are forecast.

B. NOAA Solar Radiation Activity Observation and Forecast

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

Solar Radiation Storm Forecast for Sep 01-Sep 03 2023

              Sep 01  Sep 02  Sep 03
S1 or greater   99%      1%      1%

Rationale: S1 (Minor) solar radiation storms are expected to continue
for the remainder of 01 Sep.  No significant active region activity
favorable for radiation storm production is forecast on 02-03 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 01 2023 0352 UTC.

Radio Blackout Forecast for Sep 01-Sep 03 2023

              Sep 01        Sep 02        Sep 03
R1-R2           25%           25%           15%
R3 or greater    5%            5%            1%

Rationale: No R1 (Minor) or greater radio blackouts are expected.  No
significant active region flare activity is forecast.
                        

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