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000
FXXX10 KWNP 190030
DAYTDF

:Product: 3-Day Forecast
:Issued: 2013 May 19 0030 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC contact on the Web
# http://www.swpc.noaa.gov/wwire.html
#
#             3-Day Forecast
#
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 19-May 21 2013 is 6 (NOAA Scale
G2).

NOAA Kp index breakdown May 19-May 21 2013

            May 19     May 20     May 21
00-03UT        2          4          3
03-06UT        2          4          2
06-09UT        2          3          2
09-12UT        2          3          2
12-15UT        5 (G1)     3          2
15-18UT        6 (G2)     2          2
18-21UT        6 (G2)     2          2
21-00UT        5 (G1)     3          2

Rationale: G1 (Minor) to G2 (Moderate) geomagnetic storms are expected
on day 1 (19 May) with the arrival of a coronal mass ejection (CME) from
17 May.

B. NOAA Solar Radiation Activity Observation and Forecast

Solar radiation, as observed by NOAA GOES-13 over the past 24 hours, was
above S-scale storm level thresholds.

Solar Radiation Storm Forecast for May 19-May 21 2013

              May 19  May 20  May 21
S1 or greater   60%     30%     30%

Rationale: An S1 (Minor) radiation storm is likely on 19 May with shock
passage associated with the arrival of the 17 May CME.

C. NOAA Radio Blackout Activity and Forecast

No radio blackouts were observed over the past 24 hours.

Radio Blackout Forecast for May 19-May 21 2013

              May 19        May 20        May 21
R1-R2           65%           65%           65%
R3 or greater   40%           40%           40%

Rationale: No R1 (Minor) to R2 (Moderate) radio blackouts are likely all
three days of the forecast period.  There is also a chance for an R3
(Strong) radio blackout as well, most likely from Region 1748.