3-Day Forecast

Issued: 2024 May 16 1230 UTC
Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center and processed by SpaceWeatherLive.com

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 May 16-May 18 2024 is 6 (.00NOAA scale G2).

NOAA Kp index breakdown

             May 16       May 17       May 18
00-03UT       2.67         2.33         2.33     
03-06UT       3.33         1.33         1.67     
06-09UT       6.00 (G2)    1.67         2.00     
09-12UT       4.67 (G1)    1.67         2.33     
12-15UT       5.67 (G2)    2.33         2.33     
15-18UT       4.67 (G1)    2.33         2.33     
18-21UT       3.33         3.33         2.33     
21-00UT       3.33         4.33         2.33     

Rationale

G1-G2 (Minor-Moderate) geomagnetic storms are likely on 16 May due to transient influences possibly combined with a positive polarity CH HSS.

B. NOAA Solar Radiation Activity Observation and Forecast

Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was above S-scale storm level thresholds.

Solar Radiation Storm Forecast for May 16-May 18 2024

              May 16  May 17  May 18
S1 or greater   99%     15%     10%

Rationale

R1-R2 (Minor-Moderate) conditions are expected on 16 May due to the flare potential from now departed Region 3664. Probabilities drop to a slight chance on 17-18 May from the remaining active regions on the Suns visible disk.

C. NOAA Radio Blackout Activity and Forecast

Radio blackouts reaching the R3 levels were observed over the past 24 hours. The largest was at May 15 2024 1438 UTC.

Radio Blackout Forecast for May 16-May 18 2024

              May 16        May 17        May 18
R1-R2           75%           40%           40%
R3 or greater   40%           10%           10%

Rationale

R1-R2 (Minor-Moderate) conditions are expected on 16 May due to the flare potential from now departed Region 3664. Probabilities drop to a chance on 17-18 May from the remaining active regions on the Suns visible disk.