Weekly Tropical Climate Note Issued on Tuesday 25 February 2014 Madden-Julian Oscillation over the western Pacific The Madden-Julian Oscillation (MJO) has recently gained strength over the western Pacific Ocean. The past week has seen enhanced convection over the Solomon Islands and an active monsoon trough that extends from northern Australia into the central tropical Pacific. A weak trough extends across the Indian Ocean, although convection along the trough has been suppressed, as is usual when the MJO moves into the western tropical Pacific. There is some uncertainty in model forecasts as the MJO moves towards the western hemisphere this week. Some models predict a weakening of the signal, while others maintain its strength. When the MJO signal is strong in the western Pacific and western hemisphere it can increase the risk of tropical cyclone formation in the South Pacific. It can also reduce the likelihood of large-scale monsoonal activity across the tropical Indian Ocean, the Maritime Continent and northern Australia. When the MJO weakens it has less influence on topical weather. See the Bureaus MJO Monitoring for more information on location and tracking of the MJO. ENSO state: neutral The El Niño–Southern Oscillation (ENSO) remains neutral. However, warming of the tropical Pacific Ocean is likely in the coming months, with climate models suggesting Pacific Ocean temperatures may approach or exceed El Niño thresholds in the austral winter. Model outlooks at this time of the year have lower skill than outlooks made at other times, and hence should be used cautiously. El Niño events usually, but not always, coincide with drier than normal conditions across eastern and northern Australia and an eastward shift in tropical cyclone activity in the South Pacific. The 30–day Southern Oscillation Index (SOI) value to 23 February is +2.6.The latest NINO3.4 sea surface temperature anomaly is -0.4 °C. See the Bureaus ENSO Wrap-Up which includes a compilation of computer model predictions of ENSO indices. Next update expected by 4 March 2014| Product Code IDCKGEWOOO For more information please contact [email protected] bom.gov.au/climate/tropnote/tropnote.shtml
Posted on: Tue, 25 Feb 2014 08:01:36 +0000
Trending Topics
Recently Viewed Topics
© 2015