:Product: 3-Day Forecast
:Issued: 2013 May 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 5 (NOAA Scale
G1).
The greatest expected 3 hr Kp for May 25-May 27 2013 is 5 (NOAA Scale
G1).

NOAA Kp index breakdown May 25-May 27 2013

            May 25     May 26     May 27
00-03UT        4          2          3     
03-06UT        5 (G1)     3          2     
06-09UT        3          2          2     
09-12UT        4          2          2     
12-15UT        3          2          1     
15-18UT        3          2          2     
18-21UT        3          2          2     
21-00UT        2          3          2     

Rationale: There is a chance for a G1 (Minor) geomagnetic storm on day 1
(25 May) resulting from the lingering effects of a coronal mass
ejection.

B. NOAA Solar Radiation Activity Observation and Forecast

Solar radiation, as observed by NOAA GOES-15 over the past 24 hours, was
above S-scale storm level thresholds.

Solar Radiation Storm Forecast for May 25-May 27 2013

              May 25  May 26  May 27
S1 or greater   30%     01%     01%

Rationale: The is a chance for an S1 (Minor) solar radiation storm on
day 1 (25 May).

C. NOAA Radio Blackout Activity and Forecast

No radio blackouts were observed over the past 24 hours.

Radio Blackout Forecast for May 25-May 27 2013

              May 25        May 26        May 27
R1-R2           25%           25%           25%
R3 or greater    1%            1%            1%

Rationale: A chance for an R1 (Minor) or greater radio blackout exists
through the forecast period (25-27 May).  Significant active region
flare activity is possible, most likely from Regions 1755 and 1756.