Tropical Climate Note
Issued on Tuesday 28 October 2014
Drier than normal 'build-up'
Across northern Australia, the transitional period between the dry season and the wet season is known as the 'build-up' and is usually characterised by high temperatures, high humidity and isolated thunderstorms. In general, this year's build-up temperatures have been near normal and rainfall has been drier than normal, with most of the tropical north receiving less than 10 mm for the wet season so far. Rainfall forecasts call for a continuation of below-average rainfall for at least the next month.
Arabian Sea tropical cyclone
This past week began with a moderate-to-weak signal in the Madden–Julian Oscillation (MJO) over the western Indian Ocean. Although the signal weakened, severe cyclonic storm Nilofar formed over the Arabian Sea in the region recently affected by the MJO. Nilofar is likely to make landfall near the India–Pakistan border later this week.
The MJO is forecast to continue to weaken and not have a strong influence on tropical weather for the next two weeks.
See the Bureau's MJO Monitoring for more information on the location and tracking of the MJO.
El Niño—Southern Oscillation shows little change
El Niño–Southern Oscillation (ENSO) indicators, as well as Australian rainfall patterns, continue to show some El Niño–like signatures, but remain in the neutral range. The latest NINO3.4 sea surface temperature anomaly is +0.6 °C. The latest Southern Oscillation Index value up to 26 October is −8.2.
See the Bureau of Meteorology's ENSO Wrap up for official El Niño information.
Next update expected by Wedensday 5 November 2014 | Product Code IDCKGEW000