Climate Outlook for Summer 2017 LEE Hyunsoo, PARK Jeongwon, Gong Yeonji, Kim Dong-Joon, and Lee Gyeongmi (Korea Meteorological Administration) FOCRAII, 24~26 April 2017

ENSO condition and prediction (GloSea5) Jun Jul Aug Issued in 13 Mar Issued in 10 Apr Nino3.4 SSTA FCST | INIT Apr Mar Feb May 0.53 0.80 0.94 Jun 0.58 0.98 Jul 0.81 1.24 1.28 Aug 0.84 1.47 1.40 Sep 1.00 1.56

500hPa GPH (GloSea5) Jun Jul Aug The WNPSH(Western North Pacific Subtropical High) shows slight expansion toward Korea → onset of Changma that is not later than usual Active Changma front over the southern part of Korea → a little late end of Changma The overall Changma period is likely to be near or a little longer than normal for mid/late June to late July

Behavior of EASM (GloSea5) Anomalous anticyclone over the east Siberia & Bering Sea and anomalous cyclone over northwestern Pacific is likely to have an impact on below-normal precipitation over Korea

Ensemble prediction (GloSea5) Probability of 1.5m temperature (JJA) Ensemble mean for 1.5m temperature Jun Jul Aug Probability of precipitation (JJA) Ensemble mean for precipitation ratio Jun Jul Aug

500hPa GPH (WMO LC MME) Jun Jul Aug JJA

MME Prediction (WMO LC) Ensemble mean for 2m temperature Probability of temperature Jun Jul Aug Ensemble mean for precipitation ratio Probability of precipitation Jun Jul Aug

Predictors for Changma precipitation

Dynamic processes for predictors

Diagnosis for 2017 Changma precipitation Contribution to the above-normal rainfall + Contribution to the below-normal rainfall Contribution to the near or below-normal rainfall Contribution to the below-normal rainfall

Summary ▣ ENSO will be neutral condition, and the possibility for the El Niño development is likely to be increasing for the second half of 2017. ▣ For Korea, temperature will be a little higher than normal, and precipitation is likely to be near or below normal in this summer - Changma period : near or a little longer than normal - Rainfall for Changma period : near or below normal - The westward extension of WNPSH will be weaker than normal, but its main extension is likely to be north Pacific Temperature Precipitation Below Normal Near normal Above normal Summer 20 40

Thank you !!