The Fast Break – Victoria
Soil moisture decreased across the whole state due to a drier month particularly in the southwest with some areas receiving no February rainfall. Soil moisture remains high in cropping paddocks in the north and southern perennials have shown late growth and water use to deplete their profiles on average by 33 percentage points for the month.
The Pacific Ocean surface is unchanged at a weak El Niño level but the undersea has further cooled to leave very little warm water pool behind. The cold-water pool has not really increased in size but has propagated further to the east. It is yet to upwell at the surface which would need to happen for a La Niña to become apparent. Trade winds are entirely normal across the Pacific but would need to see stronger easterlies for La Niña formation. The cloud and pressure patterns are currently more El Niño like. This event will fall apart some time in coming months, but a decaying El Niño has little effect on our climate. Many models predict a La Niña to form this winter, but caution should be exercised at this time of the year. If you’re making farm decisions on that information in autumn, it’s wrong as many times as it’s right.
The Indian Ocean is hot across the whole basin and this is predicted to stay that way for at least the next three months. The atmosphere shows some +IOD behaviour with pressure, cloud and trade winds leaning that way. The ocean surface shows a weak -IOD signal but this is mainly on the basis of a very warm Sumatran region where off Africa is still quite warm as well. The undersea off Sumatra remains cooler and the stronger southeast winds in that area at the moment might be expected to tame some of the heat out of the region if that upwells.
Warm oceans around Australia are enhanced moisture sources in the tropical areas, so it’s really about getting triggers and pathways to moisture in coming months to kick off the autumn break.
The Southern Annular Mode (SAM) spent most of February in weak to moderate positivity, pulling systems south, but this did not result in wetter conditions like the previous summer months.
The Madden Julian Oscillation (MJO) cloud wave is predicted to come into a favourable for rainfall position in two weeks’ time. It has spent the whole of February away from northern Australia. This will only be useful if the duck’s line up with a front, low or trough that can get a connection to it at the right time.
Our nemesis in autumn, high pressure, returned in February with the constant troughing from the north closing up as pressure became more dominant across the state. The actual pressure was also higher, meaning the systems were moving slower. Look for the pressure patterns to make a northward migration centred over Adelaide in the coming months to convince you autumn is behaving and not misbehaving by staying over a summer position centred over Melbourne.
My assessment of 12 climate models for Victoria is neutral for rainfall (plan for anything) with likely warmer temperatures for the next three months. Model accuracy is mixed for the next three months.
Soil moisture
Compared to 30 days earlier than 4 March 2024
The Australian Water Outlook (AWO) models the southwest plant available soil moisture as much drier at decile 1. The rest of western Victoria is average to drier at decile 2 to 7. Eastern Victoria sees some regions of the northern country and west northeast slightly wetter to average at decile 4-9. Most of Gippsland is normal. The soil moisture probe network shows most probes in the north unmoved particularly on cropping paddocks and with large reserves. In the south perennial pastures continue to use water where some southwest paddocks are bone dry. The Buchan perennial pasture decreased 58 percentage points from 98 to 40% and the Baynton annual pasture decreased 77 percentage points from 100 to 23%.
Soil moisture probe data can be accessed in real time at Agriculture Victoria’s soil moisture monitoring website.
Soil moisture probe data can be accessed in real time.
None
Brim crop | 100 |
Rutherglen crop | 72 |
Coonooer Bridge crop | 100 |
Normanville crop | 100 |
Ouyen crop | 100 |
Youanmite crop | 100 |
Goorambat crop | 77 |
Sheep Hills crop | 80 |
Taylors Lake late crop | 58 |
Paradise perennial | 48 |
Birchip crop | 96 |
Hamilton crop | 6 |
Moyston perennial | 24 |
Jancourt perennial rye | 0 |
Cowangie crop | 76 |
Baynton basalt phalaris | 92 |
Elmore crop | 70 |
Dartmoor lucerne | 24 |
Bessiebelle perennial | 10 |
Raywood annual | 55 |
Lawloit lucerne | 12 |
Omeo perennial | 10 |
Pigeon Ponds phalaris | 13 |
Yalla-Y-Poora crop | 21 |
Omeo crop | 24 |
Lake Bolac crop | 55 |
Bairnsdale annual | 78 |
Terang perennial | 0 |
Giffard crop | 69 |
Leongatha perennial | 12 |
Baynton granite phalaris | 66 |
Longwarry chicory | 66 |
Longwarry perennial rye | 66 |
Yarram ryegrass | 48 |
Greta phalaris | 49 |
Yarram prairie grass | 28 |
Greta annual pasture | 45 |
Cann River perennial | 24 |
Buchan perennial | 40 |
Bairnsdale perennial | 33 |
Greta summer pasture | 24 |
Baynton granite annual | 23 |
Model distribution summary for the next 3 months
Predicted rainfall – March to May 2024
Predictions for March to May 2024, the outlook from 12 global model forecasts for Victorian rainfall is neutral.
Model distribution summary for Victoria
Predicted temperature – March to May 2024
Predictions for March to May 2024, the outlook from 11 global model forecasts is for likely warmer across Victoria.
Model distribution summary for the next 4-6 months
Predicted rainfall – June to August 2024
Predictions for June to August 2024, the outlook from 9 global model forecasts is split between likely wetter and neutral for Victorian rainfall.
Predicted temperature – June to August 2024
Predictions for June to August 2024, the outlook from 9 global model forecasts is for likely warmer across Victoria.
Model consensus forecast for the next 6 months
Current outlook (3 March)
Phenomena | Mar-May | June-August |
---|---|---|
Pacific Ocean | Warm (El Niño) / slightly warm | Slightly cool/ normal |
Indian Ocean | Slightly warm | Slightly warm |
Rainfall | Neutral | Neutral |
Temperature | Warmer | Warmer |
Previous outlook (29 January)
Phenomena | Feb-Apr | May-July |
---|---|---|
Pacific Ocean | Warm (El Niño) / slightly warm | Slightly cool/ normal |
Indian Ocean | Slightly warm | Slightly warm |
Rainfall | Neutral | Neutral |
Temperature | Warmer | Warmer |
Sea surface temperature (SST) anomalies
National Oceanic and Atmospheric Administration (NOAA) Coral Reef Watch Daily 5 km SST Anomalies (Version 3.1) 27 January 2024.
The Equatorial Pacific Ocean surface remained the same in February. The oceanic values for NINO3 and NINO3.4 are +1.28°C and +1.23°C respectively (4 February) still at a weak El Niño. The Coral Sea to the northeast, continuing down the east coast remains much warmer than normal. The whole Indian Ocean is warmer than normal. This demonstrates enhanced moisture sources around the country.
Sea surface temperatures are the key to the world’s rainfall. For more information on how they are measured, maps created and how to read them, check out our eLearn
Equatorial Pacific sub-sea temperature anomalies
Analysis done 1 March 2024
The Pacific Ocean Equatorial sub-surface temperature cooled further over February. The region of warmer water decreased, indicating further demise of the El Niño and the cool anomaly made its way further to the east. It is yet to start upwelling at the surface off the South American coast.
Southern Oscillation Index (SOI)
30-day moving SOI
The SOI is moderately negative and at El Niño values in February, currently at -11.6 (as of 4 March 2024). The SOI ceases to be all that useful during the northern wet season as tropical pressure disturbances (such as from cyclones and the MJO) can change the values away from the underlying pattern.
© Copyright Commonwealth of Australia 2023. Bureau of Meteorology
Dipole Mode Index (DMI)
The DMI is the difference between the temperature of the west and east boxes of ocean monitored for the IOD. The DMI remains at a weak -IOD value of -0.42°C, above the threshold of -0.4°C. Water has warmed across the Sumatran measurement box and this is the key driver in the negative value, even as the African box remains warmer as well.
© Copyright Commonwealth of Australia 2023. Bureau of Meteorology.
Pacific Ocean surface wind anomalies
Wind direction and strength anomalies for the last 30 days
Equatorial trade winds in the Pacific Ocean are normal. If a La Niña is to develop, we would expect to see increased easterly wind along the equatorial Pacific. A burst off stronger southeast wind off Sumatra will probably go some way to curbing the enthusiasm of a -IOD due to underlying cooler water in this area
.
(NCEP Operational climatology data: 1985 -1996, smoothed with five-day running mean) Source: NOAA
World cloudiness anomalies
OLR Anomalies: Average of 1 February 2024 to 2 March 2024
Cloud over the international dateline junction with the equator is greater, in keeping with El Niño. Decreased cloud to the north of Australia could well be due to the phase of the MJO we spent most of February in.
Source: Bureau of Meterology
Southern Annular Mode (SAM)
AAO: Observed and GFS forecasts
Observations 1 October 2023 to 28 January 2024
The Southern Annular Mode (SAM) or Antarctic Oscillation (AAO) is currently neutral. A 30-day period from mid-December to mid-January was strongly positive. Positive SAM over summer is often associated with greater easterly flow and higher rainfall over eastern Victoria. The Bureau of Meteorology and NOAA models are in agreement that SAM will return from weak negativity to neutral over the next 2 weeks.
Source: NOAA
Madden Julian Oscillation (MJO)
MJO Phase Diagram for 19 December 2023 to 27 January 2024
In the last 30 days the Madden Julian Oscillation (MJO) has moved from a solitary state in the central Pacific (position 7) to undefined for the rest of the month. It has recently emerged with moderate strength in the central Indian Ocean (position 3). The BoM ACCESS model predicts the MJO to move into the all-important zones of 5 and 6 with moderate strength from 9-15 March. Victoria can often benefit if a front or low can pass and get a connection to this tropical moisture. It normally takes around 40 days to travel round the equator and be back in a similar position.
Air pressure
Last 30 days air pressure
Sea level pressure (mb) 30-day mean for: Saturday 3 February 2024 to Sunday 3 March 2024.
In the past 30 days the Sub Tropical Ridge of High Pressure (STR) has been in a normal summer position across Melbourne. Pressure has been building over the state and few trough lines of low pressure formed to the tropics during February. Watch for a normal northerly migration of the STR during autumn to convince yourself pressure is playing ball and not going into a blocking summer like phase.
Source: NOAA
Air pressure anomalies
Last 30 days air pressure anomaly
Operational data: Sea level pressure (mb) 30-day anomaly for: Saturday 3 February 2024 to Sunday 3 March 2024.
he Sub Tropical Ridge is higher in pressure over Australia meaning high pressure has spent more time hanging over the state and preventing rainfall triggers from passing through. In autumn this could be a major impediment to rainfall if it keeps hanging around. Lower pressure at Tahiti and higher at Darwin is why the SOI is negative, but some of this signal could be from the MJO that stalled at position 7 for much of the month.
(NCEP Operational climatology data: 1985 – 1996, smoothed with five-day running mean). Source: NOAA
Climate definitions
Read a list of climate acronyms and explanations.
Modelled climate and ocean predictions for Victoria from February 2024 run models
Twelve climate models show their predictions for the next six months for the Pacific Ocean, Indian Ocean, rainfall and temperature for Victoria.
Our new e-learn explains this table.
* Abbreviations:
MAM = March, April, May MJJ = May, June, July JJA =June, July, August
Phenomena | CGCM System 5 ECMWF Europe | CGCM ACCESS-S BoM Australia | CGCM SINTEX-F JAMSTEC Japan | CGCM CFSv2 NCEP USA | CGCM GEOS-S2S NASA USA | CGCM EPS JMA Japan | CGCM CSM1.1m BCC China | CGCM GloSea5 UKMO UK | Ensemble NMME USA | Ensemble C3S Europe | Ensemble MME APCC Korea | Ensemble SOI phase USQ/Qld Australia | |||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Month of Run | Feb | Feb | Feb | Feb | Feb | Feb | Feb | Feb | Feb | Feb | Feb | Feb | |||||
Forecast months* | MAM | MAM | MAM | MAM | MAM | MAM | MAM | MAM | MAM | MAM | MAM | MAM | |||||
Rainfall Skill MAM | Moderate | Moderate W / High E | - | Moderate/ Low Gipps | Moderate / Low SW | Moderate | - | Low | Moderate | - | - | - | |||||
Autumn Pacific Ocean NINO3.4 | Warm (El Niño) | Warm (El Niño) | Slightly warm | Normal | Normal | Slightly warm | Slightly warm | Normal | Slightly warm | Slightly warm | Slightly warm | SOI falling | |||||
Autumn Eastern Indian Ocean | Warm | Slightly warm | Warm | Warm | Slightly warm | Slightly warm | Slightly warm | Warm | Slightly warm | Slightly warm | Warm | - | |||||
Autumn Rainfall | Neutral, slightly drier far ESW, slightly wetter NE, C Gipps. | Slightly drier, neutral East Gipps | Neutral | Neutral | Neutral | Slightly drier | Neutral | Neutral, slightly drier NW | Neutral, slightly drier SW Coast | Neutral | Neutral | Neutral | |||||
Autumn Temperature | Neutral W, slightly warmer far E | Slightly warmer, neutral Gipps | Warmer | Slightly warmer | Slightly warmer | Slightly warmer | Warmer | Slightly warmer | Slightly warmer | Slightly warmer | Slightly warmer | - | |||||
Forecast months* | JJA | MJJ | JJA | JJA | JJA | - | JJA | MJJ | JJA | MJJ | JJA | - | |||||
Winter Pacific Ocean NINO3.4 | Normal | Slightly warm | Cool (La Niña) | Cool (La Niña) | Cool (La Niña) | - | Normal | Cool (La Niña) | Cool (La Niña) | Cool (weak La Niña) | Cool (weak La Niña) | - | |||||
Winter Eastern Indian Ocean | Warm | Normal | Slightly warm | Warm | Slightly warm | - | Slightly cooler (weak +IOD) | Slightly warm | Slightly warm | Slightly warm | Slightly warm | - | |||||
Winter Rainfall | Slightly wetter, neutral SW | - | Neutral, slightly drier far E | Neutral S, slightly wetter N | Neutral | - | Neutral | Slightly wetter | Slightly wetter, neutral SW | Slightly wetter, neutral SW | Neutral, slightly drier far SW | - | |||||
Winter Temperature | Slightly warmer | - | Slightly warmer | Slightly warmer E, neutral W | Slightly warmer | - | Slightly warmer | Warmer E, slightly warmer W | Warmer E, slightly warmer W | Warmer | Warmer, slightly warmer NW | - | |||||
Further Info | Operational | Operational | Experimental | Operational | Experimental | Experimental | Operational | Operational | Experimental Summary of 8 dynamic models | Experimental Summary of 9 dynamic models | Experimental Summary of 13 dynamic models | 5 phase system based on previous 2 months SOI |
Four coupled global circulation model forecasts
* Abbreviations:
MAM =March, April, May MJJ = May, June, July JJA = June, July, August
Phenomena | System 5 ECMWF Europe | ACCESS-S BoM Australia | SINTEX-F JAMSTEC Japan | CFSv2 NCEP USA |
---|---|---|---|---|
Month of Run | Feb | Feb | Feb | Feb |
Forecast months* | MAM | MAM | MAM | MAM |
Rainfall Skill MAM | Moderate | Moderate W / High E | - | Moderate / Low Gipps |
Autumn Pacific Ocean NINO3.4 | Warm (El Niño) | Warm (El Niño) | Slightly warm | Normal |
Autumn Eastern Indian Ocean | Warm | Slightly warm | Warm | Warm |
Autumn Rainfall | Neutral, slightly drier far ESW, slightly wetter NE, C Gipps. | Slightly drier, neutral East Gipps | Neutral | Neutral |
Autumn Temperature | Neutral W, slightly warmer far E | Slightly warmer, neutral Gipps | Warmer | Slightly warmer |
Forecast months* | JJA | MJJ | JJA | JJA |
Winter Pacific Ocean NINO3.4 | Normal | Slightly warm | Cool (La Niña) | Cool (La Niña) |
Winter Eastern Indian Ocean | Warm | Normal | Slightly warm | Warm |
Winter Rainfall | Slightly wetter, neutral SW | - | Neutral, slightly drier far E | Neutral S, slightly wetter N |
Winter Temperature | Slightly warmer | - | Slightly warmer | Slightly warmer E, neutral W |
Further Info | Operational | Operational | Experimental | Operational |
Four coupled global circulation model forecasts
Abbreviations:
MAM =March, April, May MJJ = May, June, July JJA = June, July, August
Phenomena | GEOS-S2S NASA USA | EPS JMA Japan | CSM1.1m BCC China | GloSea5 UKMO UK |
---|---|---|---|---|
Month of Run | Feb | Feb | Feb | Feb |
Forecast months* | MAM | MAM | MAM | MAM |
Rainfall Skill MAM | Moderate / Low SW | Moderate | - | Low |
Autumn Pacific Ocean NINO3.4 | Normal | Slightly warm | Slightly warm | Normal |
Autumn Eastern Indian Ocean | Slightly warm | Slightly warm | Slightly warm | Warm |
Autumn Rainfall | Neutral | Slightly drier | Neutral | Neutral, slightly drier NW |
Autumn Temperature | Slightly warmer | Slightly warmer | Warmer | Slightly warmer |
Forecast months* | JJA | - | JJA | MJJ |
Winter Pacific Ocean NINO3.4 | Cool (La Niña) | - | Normal | Cool (La Niña) |
Winter Eastern Indian Ocean | Slightly warm | - | Slightly cooler (weak +IOD) | Slightly warm |
Winter Rainfall | Neutral | - | Neutral | Slightly wetter |
Winter Temperature | Slightly warmer | - | Slightly warmer | Warmer E, slightly warmer W |
Further Info | Experimental | Experimental | Operational | Operational |
Three ensembles and a statistical model forecast
Abbreviations:
*MAM =March, April, May MJJ = May, June, July JJA = June, July, August
Forecast months* | NMME USA | C3S Europe | MME APCC Korea | SOI phase USQ/Qld Australia |
---|---|---|---|---|
Rainfall Skill MAM | Feb | Feb | Feb | Feb |
Autumn Pacific Ocean NINO3.4 | MAM | MAM | MAM | MAM |
Autumn Eastern Indian Ocean | Moderate | - | - | - |
Autumn Rainfall | Slightly warm | Slightly warm | Slightly warm | SOI falling |
Autumn Temperature | Slightly warm | Slightly warm | Warm | - |
Forecast months* | Neutral, slightly drier SW Coast | Neutral | Neutral | Neutral |
Winter Pacific Ocean NINO3.4 | Slightly warmer | Slightly warmer | Slightly warmer | - |
Winter Eastern Indian Ocean | JJA | MJJ | JJA | - |
Winter Rainfall | Cool (La Niña) | Cool (weak La Niña) | Cool (weak La Niña) | - |
Winter Temperature | Slightly warm | Slightly warm | Slightly warm | - |
Further Info | Slightly wetter, neutral SW | Slightly wetter, neutral SW | Neutral, slightly drier far SW | - |
Forecast months* | Warmer E, slightly warmer W | Warmer | Warmer, slightly warmer NW | - |
Rainfall Skill MAM | Experimental Summary of 8 dynamic models | Experimental Summary of 7 dynamic models | Experimental Summary of 13 dynamic models | 5 phase system based on previous 2 months SOI |
Image references
Original images used in this document are sourced from the Bureau of Meteorology under a Creative Commons 3.0 licence and from the NOAA who have a Public Domain policy. Annotations highlighting areas of interest have been added by Dale Grey.