NSW State Seasonal Update - June 2022

Prepared by NSW DPI

NSW overview

NSW received below average rainfall in June 2022. Despite the low monthly rainfall, field conditions remained wet due to high carry over soil moisture, and stored water, as well as cooler temperatures. All of NSW is currently in non-drought with the NSW DPI Combined Drought Indicator (CDI) showing 100% of NSW in the Non-Drought category at the end of June. At the beginning of July 2022, parts of eastern NSW are being impacted by severe flooding. The extent of damage to agricultural production in this region will become clearer over the coming weeks.

Generally high soil water, plant growth and rainfall indices describe productive conditions. Water availability for production remains strong, with high on-farm dam levels across much of the state. The high soil moisture and full water storages have helped to maintain ground cover. The autumn break was strong in most areas, providing opportunity for sowing temperate crops and pastures.

However, cold winter temperatures and saturated conditions in many regions continue to provide challenges for producers to attain full productivity. In particular, the difficulty of operating machinery on boggy and waterlogged soils, slower pasture growth rates, and maintaining animal welfare and nutrition in cooler wetter conditions continue to confront producers.

Despite below average rainfall in June, parts of western NSW previously in the Drought Affected categories earlier in the year, have remained in the Non-Drought category. Consistent follow-up rain is needed to maintain the improved conditions and provide opportunities for longer-term drought recovery.

Climate forecasts indicate that cool wet conditions are likely to continue across NSW this winter. The latest Bureau of Meteorology (BoM) Seasonal Outlook indicates moderately high to very high chances of above median rainfall across NSW for the three months between July and September. The ENSO Outlook status is currently at La Niña watch, indicating a 50% chance that La Niña may reform by the end of the year. The Indian Ocean Dipole (IOD) is neutral. Multiple climate models indicate that the IOD may become negative in the coming months. Sea surface temperatures in the central to eastern tropical Pacific Ocean, south of the equator, remain cooler than average. Warmer than average sea surface temperatures continue about the south of the Maritime Continent and around much of Australia. A negative IOD and the currently high SOI value provide the setting for average to above average winter rainfall over eastern Australia.

The CDI and its individual rainfall, soil moisture and crop/pasture growth metrics are leading biophysical indices of drought. Factors affecting production and economic responses usually lag the CDI. Further information about the correct interpretation of the CDI at a region and industry level is provided in the regional breakdown section of this report.

It is important to recognise the CDI provides an aggregated view of NSW, and that on-ground conditions can be different to those displayed in the maps. They provide an ‘on average’ view of a particular region only.

Rainfall

The rainfall anomaly data shows the difference between total monthly rainfall and the long-term average monthly rainfall (1961-1990; Figure 2a). Below average rainfall has been received across most of NSW in June. The lowest negative rainfall anomalies were recorded along the east coast of NSW. The highest positive rainfall anomalies were in the eastern areas of the Murray and Riverina LLS regions.

The higher rainfall totals were recorded in the east of the Murray and Riverina LLS regions where rainfall of more than 100mm has been received (Figure 2b). Areas across western and central NSW, and the Greater Sydney, North Coast and Northern Tablelands LLS regions have received less than 5mm of rainfall. For the calendar year to date coastal NSW has received between 600mm to above 2000mm of rainfall. Rainfall west of the Great Dividing Range has totalled between 100mm and 600mm (Figure 2c). Year to date rainfall has been average to above average for central NSW and very much above average for coastal NSW.

Temperature

Average to below average maximum temperatures were experienced across NSW in June (Figure 3a). The average June maximum temperatures ranged from 0°C in the southern alps to above 21°C in the North Coast LLS region. Areas west of the Great Dividing Range had maximum temperatures above 12°C, and above 18°C for north western areas of NSW (Figure 3b).

Minimum temperatures were generally slightly above average across southern NSW in June, and more than 2°C below average across parts of northern NSW (Figure 3c). The average June minimum temperatures were above -6°C in eastern NSW and above 3°C in the west (Figure 3d). Minimum temperatures in the Tablelands ranged from -6 to 3°C, whilst frost was experienced in the Northern, Central, and Southern Tableland regions, and also in the southern alps where temperatures below -3°C were recorded (Figure 3e).

Normalised Difference Vegetation Index (NDVI) Anomaly

The seasonal Normalised Difference Vegetation Index (NDVI, Figure 4) indicates that plant greenness levels are close to normal, to well above normal across most of NSW for the April to June period. Slightly lower than normal plant greenness remains evident across parts of the Western, Central West, and North West LLS regions. The Central West and South East LLS regions are missing data due to cloud cover and parts of these regions are shaded white in this month's map. Some of the extremely negative NDVI areas (brown patches) are water bodies.

NSW Farm Dam Survey

The NSW Farm Dam Survey indicates dam levels are generally greater than 80% of capacity across NSW (Figure 5). Some areas of the Western, Riverina and Murray LLS regions of NSW maintain farm dam levels at less than 20% of capacity. Data is unavailable for large areas of NSW due to cloud cover this past month.

Soil Water Index

The Soil Water Index (SWI, Figure 6) indicates the majority of NSW is currently in the above average category. Large areas of northern, central, and south-eastern NSW are in the extremely high category. This is a result of the rainfall that has been received over the past several months and the cooler temperatures experienced in June.

Plant Growth Index

The Plant Growth Index (PGI, Figure 7) indicates that the majority of NSW is in the above average category at the end of June. Parts of south-western and western NSW reflect a similar pattern with the SWI and are in the average category. Areas of south-eastern, central, and northern NSW in the extremely high category also somewhat reflect the SWI.

Rainfall Index

The Rainfall Index (RI, Figure 8) indicates that at the end of June most of NSW is in the above average category or higher. However, the below average rainfall received in June has resulted in some pockets of the Western, and North West LLS regions moving into the average RI category. Most of central and eastern NSW is currently in the extremely high category; this reflects the distribution of above average rainfall accumulated over the last 12 months.

Drought Direction Index

The Drought Direction Index (DDI, Figure 9) tracks the 150-day trend of daily rainfall totals. The DDI indicates a strong drying trend along the east coast and Tableland regions. Weaker drying trends can be seen in central and northern areas of NSW. There is a weak wetting trend throughout the south of the state. Strong wetting trends are seen in the eastern areas of the Murray and Riverina LLS regions reflecting the high rainfall received in these areas in June. The drying trends are a result of extremely high rainfall recorded in late summer and early autumn of 2022. Recent conditions, although still wet in absolute terms, are lower than the extremely high totals recorded three months ago. Importantly the weak to strong drying trend does not indicate the emergence of a drought in the regions, rather it indicates a degree of drying following on from the wet summer and autumn.

Changes in the individual drought indicators may have occurred since this update was released. For the most current information, please visit DroughtHub.

Adverse events

At the beginning of July 2022, parts of eastern NSW including the Western Sydney basin and the Hunter continue to be impacted by recurring flooding. The extent of damage to agricultural production in this region will become clearer over the coming weeks.

CDI status for the regions

Figure 10 displays the CDI status for each individual Local Land Services (LLS) region to 30 June 2022. The following regional descriptions are based on data available until the end of June 2022.

Murray and Riverina regions

The Combined Drought Indicator (CDI, Figure 11) shows that all of the Riverina and Murray Local Land Services (LLS) regions remain in the Non-Drought category at the end of June.

The seasonal NDVI anomaly data (Figure 12) shows that most of the Murray and Riverina regions were experiencing higher than normal plant greenness levels for the April to June period.

The time series charts (Figure 13) show the individual response of the drought indices for Hay, Temora, Finley, and Moulamein. Temora and Finley remain steady with average to high soil water, plant growth and rainfall indices. Continued rainfall and cooler than average temperatures have allowed Hay to remain in the Non-Drought category. Although recent rainfall has improved conditions at Moulamein, further rainfall is required to maintain conditions in the region. To access a time series for your Parish, visit the Combined Drought Indicator website.

The Combined Drought Indicator (CDI) is a tool that monitors drought conditions across NSW. The drought categories are based on assessing the response of three drought indicators: soil water, plant growth and rainfall. The indicators track the data over the past 12 months and show how the indices are tracking compared to long-term averages. The information provided in the map is aggregated to a Parish level and provides a regional assessment of conditions. Variability within and between farms is possible and this may not be reflected in the CDI map.

Western region

The Combined Drought Indicator (CDI, Figure 14) shows that all of the region is in the Non-Drought category. Continued rainfall in the north of the region throughout June has meant that minor to moderate flood alerts are still in place. The DPI continues to closely monitor conditions in Western LLS.

The seasonal NDVI anomaly data (Figure 15) shows variability across the Western LLS region. Much of the region is experiencing near normal to high levels of plant greenness for the April to June period. Areas in the far west and south-west continue to have slightly lower than normal plant greenness levels. Flood affected areas may also be represented by lower levels of greenness.

The time series charts (Figure 16) show the individual response of the drought indices for Bourke, Ivanhoe, Wentworth, and Broken Hill. Average to high soil water, plant growth, and rainfall indices are represented at all locations. Recent rainfall has continued to build on the drought recovery and parts of the region are now facing the challenges of flooding and continued wet cool weather into winter. NSW continues to monitor the Western LLS region closely. To access a time series for your Parish, visit the Combined Drought Indicator website.

The Combined Drought Indicator (CDI) is a tool that monitors drought conditions across NSW. The drought categories are based on assessing the response of three drought indicators: soil water, plant growth and rainfall. The indicators track the data over the past 12 months. This shows how the indices are tracking compared to the long-term averages. The information provided in the map is aggregated to a Parish level and provides a regional assessment of conditions. Variability within and between farms is possible and this may not be reflected in the CDI map.

North West, Northern Tablelands and North Coast regions

The Combined Drought Indicator (CDI, Figure 17) shows that the North West, Northern Tablelands and North Coast Local Land Service regions are in the Non-Drought category.

The seasonal NDVI anomaly data (Figure 18) indicates near to above-normal greenness across most of the regions for the April to June period. Parts of the North West have average to slightly below average levels of greenness. The white areas west of Walgett and east of Lightning Ridge in the North West is missing data due to cloud cover. The dark brown areas showing below average greenness south of Lismore and east, north-east of Grafton are likely be due to flooding impacts over the past few months.

The time series charts (Figure 19) show the individual response of the drought indices for Moree, Walgett, Tenterfield and Lismore. The indicators remain high at all locations. To access a time series for your Parish, visit the Combined Drought Indicator website.

Variable rainfall received across the North West, Northern Tablelands, and North Coast LLS regions in June continued to provide wet conditions following on from the flood events seen earlier this year. Primary producers impacted by flooding still face the challenge of returning livestock and cropping systems to full production.

The Combined Drought Indicator (CDI) is a tool that monitors drought conditions across NSW. The drought categories are based on assessing the response of three drought indicators: soil water, plant growth and rainfall. The indicators track the data over the past 12 months and shows how the indices are tracking compared to the long-term averages. The information provided in the map is aggregated to a Parish level and provides a regional assessment of conditions. Variability within and between farms is possible and this may not be reflected in the CDI map.

Central Tablelands, Central West, Hunter and Greater Sydney regions

The Combined Drought Indicator (CDI; Figure 20) shows that the Central West, Central Tablelands, Hunter and Greater Sydney Local Land Services (LLS) regions continue to experience Non-Drought conditions at the end of June. Generally these are productive conditions however, heavy rainfall experienced in the last week due to an east coast low have resulted in flooding. Flood alerts are current for these regions. The NSW DPI continues to closely monitor conditions in these regions.

The seasonal NDVI anomaly data (Figure 21) shows near normal to very high levels of plant greenness across most of the LLS regions for the April to June period. The white patches in Figure 21 are missing data due to cloud cover.

The time series charts (Figure 22) show the individual response of the drought indices for Cowra, Condobolin and Singleton. The CDI indicators remain high at all locations. Generally these are productive conditions however, given ongoing wet conditions and cooler temperatures the productivity challenges of working with saturated soils, lower pasture growth rates and maintaining animal welfare continue. To access a time series for your Parish, visit the Combined Drought Indicator website.

The CDI is a tool that monitors drought conditions across NSW. The drought categories are based on assessing the response of three drought indicators: soil water, plant growth and rainfall. The indicators track the data over the past 12 months and show how the indices are tracking compared to the long-term averages. The information provided in the map is aggregated to a Parish level and provides a regional assessment of conditions. Variability within and between farms is possible and this may not be reflected in the CDI map.

South East region

The Combined Drought Indicator (CDI, Figure 23) shows that the South East Local Land Services region remains in the Non-Drought CDI category. Generally these are productive conditions however, heavy rainfall experienced in the last week due to an east coast low have resulted in flooding. Flood alerts are current for these regions. The NSW DPI continues to closely monitor conditions in these regions.

The seasonal NDVI anomaly data (Figure 24) showed near normal to high levels of plant greenness across most of the region for the April to June period. The white patches in Figure 24 are missing data due to cloud cover.

The time series charts (Figure 25) show the individual response of the drought indices at Bega, Goulburn and Cooma. The three regions remain in the Non-Drought category with high soil water, plant growth and rainfall indices. Generally these are productive conditions however, given ongoing wet conditions and cooler temperatures the productivity challenges of working with saturated soils, lower pasture growth rates and maintaining animal welfare continue. To access a time series for your Parish, visit the Combined Drought Indicator website.

The Combined Drought Indicator (CDI) is a tool that monitors drought conditions across NSW. The drought categories are based on assessing the response of three drought indicators: soil water, plant growth and rainfall. The indicators track the data over the past 12 months and shows how the indices are tracking compared to the long-term averages. The information provided in the map is aggregated to a Parish level and provides a regional assessment of conditions. Variability within and between farms is possible and this may not be reflected in the CDI map.

Official national outlook

The official national outlook was released by the Bureau of Meteorology (BoM) on 30 June 2022. Rainfall during July to September is likely to be above median for eastern, central, and northern Australia. The risk of flooding remains high for south eastern Australia due to high soil moisture, high stream flows, and predicted above median rainfall.

Maximum temperatures are likely to be cooler than average for central and eastern Australia during the July to September period. Northern, south west and south eastern Australia are likely to be warmer than median. Minimum temperatures for July to September are likely to be above median across Australia.

The Bureau issues a new 3-month seasonal update weekly, each Thursday afternoon.

NSW outlook

NSW has a 60% to above 80% chance of receiving above median rainfall between July and September with the highest rainfall forecast in the Hunter, eastern Central Tablelands, and Greater Sydney regions (Figure 26).

The maximum temperature outlook indicates a less than 40% chance of warmer than median temperatures across western, central and northern NSW. There is a 55% to 75% chance of above median maximum temperatures in south eastern NSW (Figure 27).

There is a 75% to above 80% chance of warmer than median overnight temperatures across NSW. Parts of southern and north eastern NSW have a 70% to 80% chance of warmer overnight temperatures (Figure 28).

Global climate drivers

El Niño–Southern Oscillation (ENSO)

The Bureau of Meteorology’s (BoM) El Niño-Southern Oscillation (ENSO) Outlook was released on 5 July 2022. The 2021-22 La Niña has ended and ENSO indicators are now neutral. As some climate models suggest that La Niña may re-form, the ENSO Outlook status is currently at La Niña watch; this indicates that there is a 50% chance that La Niña may re-form by the end of the year. Cloudiness around the Date Line and the SOI continue show a La Niña-like signal.

Southern Oscillation Index

The 30-day Southern Oscillation Index (SOI; Figure 29) for the 30 days ending 3 July was +20.2. The 90-day SOI value was +19.5. Sustained negative values of the SOI below −7 typically indicate El Niño while sustained positive values above +7 typically indicate La Niña

Sea surface temperatures (SST)

Sea surface temperatures (SST) are near average along the equator in the tropical Pacific Ocean. SSTs are coolest along the South American coastline and cooler than average over the tropical central and eastern Pacific ocean south of the equator. Warmer than average SSTs continue around the south of the Maritime Continent and much of Australia (Figure 30).

The latest values of the three NINO indices in the tropical Pacific for the week ending 3 July were: NINO3 -0.1°C, NINO3.4 -0.3°C, NINO4 -0.5°C.

Persistent NINO3 or NINO3.4 values warmer than +0.8 °C are typical of El Niño, while persistent values cooler than −0.8 °C typically indicate La Niña.

Sea sub-surface temperatures

The four-month sequence of equatorial Pacific sub-surface temperature anomalies (to 16 June 2022) shows weak cool anomalies in the far eastern equatorial Pacific Ocean (Figure 31). Warm anomalies down to 400m depth west of 140°E extend east and rising to 50 to 150m depth at 120°W.

Indian Ocean (IOD)

The Indian Ocean Dipole (IOD) is currently neutral. However, all five international climate models surveyed by the Bureau of Meteorology indicate that the IOD will become negative in July. A negative IOD increases the likelihood of above average winter-spring rainfall across Australia. The latest weekly value of the Indian Ocean Dipole (IOD) index to 3 July 2022 was -0.69 °C.

Southern Ocean (Southern Annular Mode – SAM)

The Southern Annular Mode (SAM) index is positive (as of 5 July) and is expected to remain neutral to positive in July (Figure 32). A positive SAM typically has a drying influence on parts of south-east Australia.

The Southern Annular Mode (SAM) refers to the north-south shift of rain-bearing westerly winds and weather systems in the Southern Ocean compared to the usual position. This indicator can be quite volatile and generally influences weather conditions on 1-3 week timescales. SAM forecasts are highly uncertain beyond 2-3 weeks.

How does it work?

Much of the information in the Seasonal Conditions Report is sourced from the NSW DPI Enhanced Drought Information System (EDIS) ™. The EDIS system is currently available in prototype form and is subject to an intensive ground truthing process. For more information, visit the interactive website via DroughtHub.

EDIS is an ongoing project aimed at improving the quality and timeliness of efforts to monitor conditions across the state. Key features of the system are:

• It tracks drought by using four indicators; rainfall, soil water, plant growth, as well as tracing rainfall trends. Agronomic conditions have equal value to rainfall recorded at meteorological stations.
• The Combined Drought Indicator (CDI) brings this information together and has been designed to characterise developing drought conditions. The key purpose for building the CDI was as a drought early warning system.
• The rainfall, soil moisture and plant growth indicators in EDIS account for conditions over a 12-month window. This provides a compromise between a highly sensitive indicator (e.g. six months) and a less sensitive indicator (e.g. 24 months).
• Climate and remote sensing data drive the information system at a high resolution, but the CDI is reported at a Parish level.
• Because of its configuration and purpose, there will be differences to the indicator used in the National Drought Monitoring Framework (the Australian Rainfall Deficiency Analyser) which relies on rainfall alone.
• The CDI has three drought categories that characterise NSW according to drought intensity as well as the main drivers of a drought event (meteorological, hydrological and agronomic). DPI considers areas Drought Affected to be experiencing a drought event.
• The Drought Affected category encompasses a wide range of conditions from the very early stages of drought entry through to a drought event becoming intense. This enables the drought monitoring system to detect a drought event early. It is also possible to stay in the Drought Affected category for some period of time.

The way in which the indicators are combined to form the CDI is described in Table 1 below.

Table 1: Description of the Combined Drought Indicator framework

The NSW State Seasonal Update is provided each month by the NSW DPI Climate Branch.

Information used in this report was primarily sourced from the Australian Bureau of Meteorology, the US National Oceanic and Atmospheric Administration, the International Research Institute for Climate and Society (Columbia University), Geoscience Australia’s Digital Earth Australia Program, and NSW Department of Primary Industries.

Maps in this document contain data which is © Spatial Services – NSW Department of Finance, Services and Innovation (2022), Panorama Avenue, Bathurst 2795 and data which is © Commonwealth of Australia 2022, Australian Bureau of Meteorology, Melbourne. All rights reserved.

The seasonal outlooks presented in this report are obtained from the Australian Bureau of Meteorology and other sources (including World Meteorological Organisation Global Producing Centres). These outlooks are general statements about the likelihood (chance) of (for example) exceeding the median rainfall or minimum or maximum temperatures. Such probability outlooks should not be used as categorical or definitive forecasts, but should be regarded as tools to assist in risk management and decision making. Changes in seasonal outlooks may have occurred since this report was released.

All climate and remote sensing input data is supplied to the Enhanced Drought Information System ™ under the Australian Creative Commons Licence (CCY 4.0) and is made available by the Terrestrial Ecosystem Research Network.