You do not have a default location set
To set your location please use the search box to find your location and then click "set as my default location" on the local weather page.

12-Month Rainfall Forecast

  1. North Coast & Tableland 12-month Rainfall Forecast

    May
    24
    Jun
    24
    Jul
    24
    Aug
    24
    Sep
    24
    Oct
    24
    Nov
    24
    Dec
    24
    Jan
    25
    Feb
    25
    Mar
    25
    Apr
    25

    10

    5
    0

    8
    7
    7
    7
    7
    9
    8
    7
    1
    1
    5
    8

    Rainfall deciles

    10
    Well above normal
    8 - 9
    Above normal
    4 - 7
    Near normal
    2 - 3
    Below normal
    1
    Well below normal

    Issue Notes

    Issued 14 May 2024

    ENSO status: La Niña Watch declared. IOD status: Neutral, becoming positive. SAM status: Neutral, favouring positive in winter. The El Niño Southern Oscillation (ENSO) is now in a La Niña Watch, meaning there is approximately a 50% chance of a La Niña developing this year. Ocean cooling is occurring in the eastern Pacific, with 3 out of 7 global models forecasting a La Niña to develop in 2024. Warmer than normal waters are situated in the Coral Sea, providing moisture and humidity to the east coast. The atmosphere continues to be neutral. A La Niña typically increases rainfall over central Australia, Qld and NSW, but has little effect on southern WA, SA, Vic and Tas during winter. The Indian Ocean Dipole (IOD) is in a neutral phase. Ocean temperatures are at record levels in the western Indian Ocean, and upwelling is occurring along the Java Coast in Indonesia. However, the upwelling is mostly occurring outside the IOD East region, and is therefore not reflected in the IOD Index, which is sitting justbelow thresholds. Persistent southeasterly winds have set in, and look to remain strong despite a burst of tropical activity in the region. Models are suggest a tropical low could form in the Bay of Bengal over the coming fortnight, that would help solidify a positive IOD event. A positive IOD reduces the number of northwest cloudbands that cross Australia during winter and spring, reducing rainfall across central and southeastern parts of Australia. The Southern Annular Mode (SAM) is neutral but is expected to favour a positive phase during winter. Furthermore, the long-wave pattern around Antartica is favouring high pressure near Australia for most of June and July, akin to a positive SAM. A positive SAM increases easterly winds across Australia. This leads to increased rainfall and thunderstorm activity in the east, while reducing cold fronts and rainfall over southern Australia, particularly for southwest WA. Rainfall outlooks are showing slightly below average rainfall over winter (mostly June andJuly) for WA, and most of SA, Vic and Tas. Conversely, above average rainfall is expected for eastern parts of Qld and NSW, and potentially eastern Tas. Outlooks turn close to average in August throughout mainland Australia, with Tas still showing drier than normal.

    Forecast Explanation

    Notes on the concept of deciles

    If all the data in a record are ranked from lowest to highest they can then be divided into 100 equal blocks. These blocks are known as percentiles. The values that fall into the lowest 10% range (from 0 to 10%) are said to be in the first decile, those in the group 10+% to 20% are in the second decile, and so on. Those in the group 90+% to the maximum value recorded are in the 10th decile. The 50% value is a special one known as the 'median'. It is noteworthy since there is the same number of records above and below its value.

    Deciles have been found to be very useful for analysing rainfall in particular as its distribution is not the normal bell-shape distribution but is skewed towards many low values with only a few high values. The deciles can be described in qualitative terms. A table is provided in the accompanying results.