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CHART DISCUSSION FRI 08 MAY 2020(including an analysis of the impact of the Madden-Julian Oscillation on Australian rainfall ..

(slides 2, 3, 4, & 5) and two questions ..

(slides 7 & 14)

But firstly, the Future Synoptic Evolution (in summary)

Go To (for surface patterns):http://www.weather-climate.com/SurfacePressure.html

And (for upper air patterns):http://www.weather-climate.com/JetStreams.html

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Chart Discussion: Fri-08-May-2020 (Harvey Stern)

AND NOW, A DIVERSION:

An illustration of the impact on the Australian monthly rainfall

anomaly of the Madden-Julian Oscillation (MJO), based upon its

phase on the last day of the preceding month

separating that impact from the various impacts of other drivers

of Australia’s climate, defined by the Southern Oscillation Index

(SOI), the Multi-Variate Enso Index (MEI), the Indian Ocean

Dipole (IOD), and the Southern Annular Mode (SAM).

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Difference from average rainfall for all MJO events from 1979-2012 for November-March for the eightphases described in the text. The green shading denotes above-average rainfall, and the brown shadingshows below-average rainfall. To first order, the green shading areas correspond to the extent of theenhanced convective phase of the MJO and the brown shading areas correspond to the extent of thesuppressed convective phase of the MJO. Note eastward shifting of shaded areas with each successivenumbered phase as you view the figure from top to bottom....from Jon Gottschalck, 2014

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During Phase 1, the near-equatorial enhanced convection is found over Africa. Following Phase 1, as the regionof enhanced convection moves from Africa to the western Indian Ocean, the average rainfall across Australia isincreased in all months, especially during autumn.

During Phase 2, the near-equatorial enhanced convection is found over the western Indian Ocean. FollowingPhase 2, as the region of enhanced convection moves from the western Indian Ocean to the eastern IndianOcean, the average rainfall across Australia is increased in all months, especially during autumn.

During Phase 3, the near-equatorial enhanced convection is found over the eastern Indian Ocean. FollowingPhase 3, as the region of enhanced convection moves from the eastern Indian Ocean to the western part of whatis referred to as the Maritime Continent (Indonesia), the average rainfall across Australia is increased in mostmonths but is diminished slightly in spring months.

During Phase 4, the near-equatorial enhanced convection is found over the western part of what is referred toas the Maritime Continent (Indonesia). Following Phase 4, as the region of enhanced convection moves from thewestern part of Indonesia to the eastern part of Indonesia, the average rainfall across Australia is diminishedslightly in most months.

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During Phase 5, the near-equatorial enhanced convection is found over the eastern part of what is referred to asthe Maritime Continent (Indonesia). Following Phase 5, as the region of enhanced convection moves from theeastern part of Indonesia to the western Pacific, the average rainfall across Australia is diminished in all months,especially in autumn.

During Phase 6, the near-equatorial enhanced convection is found over the western Pacific. Following Phase 6,as the region of enhanced convection moves from the western Pacific to the central Pacific, the average rainfallacross Australia is diminished in all months, especially in autumn.

During Phase 7, the near-equatorial enhanced convection is found over the central Pacific. Following Phase 7,the Pacific convection often dies out, and as a new region of near-equatorial enhanced convection develops overthe Western Hemisphere (South America), the average rainfall across Australia is diminished in most months butis increased slightly in spring.

During Phase 8, the near-equatorial enhanced convection is found over the Western Hemisphere (SouthAmerica). Following Phase 8, as the region of enhanced convection over South America moves to Africa, theaverage rainfall across Australia is increased slightly in most months.

Yesterday’s Chart and SATPIC

Chart Discussion: Fri-08-May-2020 (Harvey Stern)

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Previous day’s SATPIC (including Weatherzone lightning)

Thunderstorms embedded in front south of the Bight?

Chart Discussion: Fri-08-May-2020 (Harvey Stern)

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Today’s Chart and SATPIC

Chart Discussion: Fri-08-May-2020 (Harvey Stern)

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Last week’s NWP Model Predictions for Yesterday

Chart Discussion: Fri-08-May-2020 (Harvey Stern)

Yesterday’s Indian Ocean Chart

(to loop sequence go to: http://www.bom.gov.au/australia/charts/archive/index.shtml )

Chart Discussion: Fri-08-May-2020 (Harvey Stern)

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Chart Discussion: Fri-08-May-2020 (Harvey Stern)

Yesterday’s Pacific Ocean Chart

(to loop sequence go to: http://www.bom.gov.au/australia/charts/archive/index.shtml )

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Rainfall – Last Week

Chart Discussion: Fri-08-May-2020 (Harvey Stern)

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Climate IndicesLink to recent trend in sea surface temperature distribution:

▪http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_update/gsstanim.gif

Chart Discussion: Fri-08-May-2020 (Harvey Stern)

▪Negative Indian Ocean Dipole possible in 2020

Also, possible La Niña ? …

Are we seeing the early signs of a La Niña developing or is it tooearly to tell?Certainly, the Humboldt current is presently not upwelling muchcold anomaly water . . .

http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_update/gsstanim.gif

Chart Discussion: Fri-08-May-2020 (Harvey Stern)

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Australian Climate OutlookIssued: 07 May 2020

Winter is likely to be wetter than average for most of the

continent. However, parts of the tropical north—which are now

into their dry season—have roughly equal chances of being

wetter or drier than average.

Melbourne 30-Day-Outlook …

Go To:

http://www.weather-climate.com/00utc07may2020.html

… and scroll down.

Chart Discussion: Fri-08-May-2020 (Harvey Stern)

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