southern hemisphere: weather & climate over major crops areas
DESCRIPTION
Southern Hemisphere: Weather & Climate over Major Crops Areas. Update prepared by Climate Prediction Center / NCEP 19 April 2010. For Real-time information: http://www.cpc.noaa.gov/products/JAWF_Monitoring/. Outline. Highlights ENSO Current Status MJO Current Status - PowerPoint PPT PresentationTRANSCRIPT
Southern Hemisphere: Weather & Climate over Major
Crops Areas
Update prepared byClimate Prediction Center / NCEP
19 April 2010
For Real-time information:
http://www.cpc.noaa.gov/products/JAWF_Monitoring/
Outline
• Highlights
• ENSO Current Status
• MJO Current Status
• Monsoons Current Status
• Southern Hemisphere Circulation
• Rainfall & Temperature Patterns
• NCEP/GFS Model Forecast
• Forecast Verification
Australia: Rainy weather continued across portions of Australia’s northern coastline, but mostly dry weather prevailed across key cotton and sorghum croplands. The GFS forecasts wet weather to spread eastward across northern Australia and develop along Queensland’s eastern coastline, with mostly light showers or dryness in southern Queensland and northern NSW.
Southern Africa: Showers were observed from Kwa-Zulu Natal through the central corn belt in South Africa. The GFS forecasts the rainfall to shift northeastward into northern South Africa, Zimbabwe, and Mozambique during the upcoming week.
South America: Several weeks of dry weather in central Brazil may indicate an early termination of the rainy season. The GFS forecasts a strong cold front to push northward out of Argentina, bringing heavy rain to southern Brazil and northeastern Argentina, which have experienced several weeks of dryness as well. Chilly weather (minimums of 0 - 5°C) are expected across Buenos Aires and La Pampa in Argentina.
Highlights
ENSO Current Status
General Summary:
• El Niño is present across the equatorial Pacific Ocean.
• Sea surface temperatures (SST) are more than 1.0ºC above-average across much of the central and east-central equatorial Pacific.
• Based on current observations and dynamical model forecasts, El Niño is expected to continue through the Northern Hemisphere spring 2010 and transition to ENSO-neutral conditions by summer 2010.
During the last 4 weeks (21 Mar – 17 Apr 2010), equatorial SSTs were more than 1.0°C above average between 170°E and the west coast of S. American.
For more information go to: http://www.cpc.noaa.gov/products/precip/CWlink/MJO/enso.shtml
MJO Current StatusThe MJO Index showed little to no signal nor any eastward propagation during the previous week, indicating no presence of an MJO event.
The GFS MJO index forecasts indicate that the signal will continue to be weak to nonexistent during the upcoming week.
The axes (RMM1 and RMM2) represent daily values of the principal components from the two leading modes
The triangular areas indicate the location of the enhanced phase of the MJO
Counter-clockwise motion is indicative of eastward propagation. Large dot most recent observation.
Distance from the origin is proportional to MJO strength
Line colors distinguish different months
MJO Index -- Recent Evolution Ensemble GFS (GEFS) MJO Forecast
RMM1 and RMM2 values for the most recent 40 days and forecasts from the ensemble Global Forecast System (GEFS) for the next 15 days
light gray shading: 90% of forecasts
dark gray shading: 50% of forecasts
Yellow Lines – 20 Individual Members
Green Line – Ensemble Mean
For more information go to: http://www.cpc.noaa.gov/products/precip/CWlink/MJO/mjo.shtml
Southern Hemisphere Monsoons Current Status
South America Southern Africa Australia
Long-term precipitation accumulations have improved across much of southern Africa’s corn growing regions. Central Mozambique has continued to miss out on precipitation that has fallen across other regions. Below-average rainfall was also observed in Kwa-Zulu Natal’s sugarcane region.
For more information go to: http://www.cpc.noaa.gov/products/Global_Monsoons/
Rainfall Anomalies: Last 90 Days
Rainy season precipitation accumulations during the previous three months have been generally below-average across South America, with small, isolated pockets in eastern Argentina and Uruguay, southeastern and eastern Brazil, and parts of the Amazon receiving above-average rainfall.
Near- to above-average rainfall during the previous three months was observed across the eastern half of Australia. In contrast, persistently below-average rainfall was observed across northern Western Australia.
Monsoon Season: NOV-APR
Monsoon Season: OCT-MAR
Monsoon Season: NOV-APR
Rainfall Anomalies: Last 90 Days Rainfall Anomalies: Last 90 Days
Southern Hemisphere Circulation200-hPa, 925-hPa Wind & Temperature Anomalies - Recent 7 days
• During 11 – 17 April 2010, an area of enhanced anomalous 200-hPa anticyclonic circulation was centered just south of Africa, while enhanced anomalous 200-hPa cyclonic circulation was observed near eastern Brazil. Note the strong upper-level convergence observed across eastern Brazil (brown oval, top panel), which helped promote anomalous sinking motion through the atmosphere, suppressing convective activity (see next slide for more detail).
• At the low levels of the atmosphere, below-average temperatures were observed along a swath from northwestern through southeastern Australia.
Low-level (925 hPa or ~600 m) wind and temperature anomalies are based on the NCEP Climate Data Assimilation Systems (CDAS) analysis. The patterns of anomalous temperature and wind at 925-hPa are usually similar to surface observations.
Note: Areas with surface pressure below 925-hPa are masked out.
A
CA
AA
Southern Hemisphere Circulation
Rising motion (negative omega, yellow/red shading), usually associated with wetter-than-average conditions.
Sinking motion (positive omega, blue shading), usually associated with drier-than-average conditions.
Omega Anomalies and Total Precipitation - Recent 7 days
• During 11 – 17 April 2010, strong anomalous sinking motion (positive omega, blue oval top panel) corresponded to upper level convergence (see previous slide), suppressing convection across eastern Brazil (note the dryness in the brown oval, bottom panel). In contrast, anomalous rising motion (negative omega) corresponded to widespread showers and thunderstorms across northwestern and central Australia.
CPC daily gridded precipitation analysis over land only. The daily gauge analysis is created on a 0.5 degree lat/lon over the global land by interpolating gauge observations from ~30,000 stations.
Australia
• Rainfall Total & Anomaly Patterns• Temperature Patterns• GFS Forecast
Rainfall Total & Anomaly Patterns: Last 7 Days
Total Anomaly
During the last 7 days, widespread moderate to heavy rainfall fell across northern coastal areas of Western Australia and Northern Territory. Scattered light to moderate rainfall was observed across central Queensland.
Rainfall Total & Anomaly Patterns: Last 15 Days
Total Anomaly
During the previous 15 days, widespread rainfall fell across most of the continent, including the arid outback regions of central Australia. In contrast, below-average rainfall was observed along and east of the Great Dividing Range in eastern Australia.
Rainfall Total & Anomaly Patterns: Last 30 Days
Total Anomaly
During the previous 30 days, most regions received rainfall across Australia. Below-average rainfall was observed across southern Queensland and northern NSW, extending southward along and east of the Great Dividing range in southeastern Australia. Heavy rain associated with Tropical Cyclone Paul was observed the regions bordering the Gulf of Carpentaria.
Recent Evolution: RainfallLast 30 Days
• 30-day rainfall time series across Australia’s summer croplands show the recent rainfall across most areas, but note the dryness in southern Queensland, and increasing dryness in northern New South Wales (top right and bottom right panels).
Temperature (°C)Based on GTS Stations (no QC)
Extreme Minimum
Anomaly
Extreme Maximum Mean
• During 11 – 17 Apr 2010, temperatures across eastern Australia were generally near to below-average.
NCEP/GFS Precipitation Forecasts
Total Anomaly
For Days 1-7 (19 – 25 Apr 2010), the GFS forecasts moderate to heavy rainfall across the Gulf of Carpentaria region and along coastal Queensland’s primary sugarcane regions. Mostly dry weather is forecast to continue across Queensland’s and New South Wales’ cotton and sorghum croplands.
Forecasts from 19 Apr 2010 – Days 1-7
NCEP/GFS Precipitation Forecasts
Total Anomaly
Forecasts from 19 Apr 2010 – Days 8-14
For Days 8-14 (26 Apr – 2 May 2010), heavy rain is forecast to continue across coastal Northern Territory and along Queensland’s eastern coastline. Dryness or light showers are forecast elsewhere.
Forecast Verification: Australia
Total
Anomaly
Forecast from 5 Apr 2010 Valid 12 – 18 Apr 2010
Forecast from 12 Apr 2010 Valid 12 – 18 Apr 2010
Observed 12 – 18 Apr 2010
Anomaly Anomaly
Total Total
Image not available
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Southern Africa
• Rainfall Total & Anomaly Patterns• Temperature Patterns• GFS Forecast
Rainfall Total & Anomaly Patterns: Last 7 Days
Total Anomaly
• During the last 7 days, light showers overspread South Africa’s central and southern Corn belt and parts of Mozambique, while dry weather prevailed elsewhere.
Rainfall Total & Anomaly Patterns: Last 15 Days
Total Anomaly
During the last 15 days, above-average rainfall extended from Zimbabwe and southern Mozambique southward into the eastern half of South Africa.
Rainfall Total & Anomaly Patterns: Last 30 Days
Total Anomaly
During the last 30 days, generally above-average precipitation was observed across southern Africa’s primary croplands.
Recent Evolution: RainfallLast 30 Days
• 30-day rainfall time series depict the recent above-average rainfall across the eastern half of southern Africa, while mostly dry seasonable weather prevailed across southwestern South Africa.
Temperature (C)Based on GTS Stations (no QC)
Extreme Minimum
Anomaly
Extreme Maximum Mean
Temperatures across southern Africa were generally slightly above-normal during the previous 7 days, with maximums reaching the low 30s°C across the outer fringes of South Africa’s maize triangle.
NCEP/GFS Precipitation Forecasts
Total Anomaly
Forecasts from 19 Apr 2010 – Days 1-7
For Days 1-7 (19 – 25 Apr 2010), moderate to locally heavy rainfall is forecast across eastern South Africa, Zimbabwe, and Mozambique, including areas of central Mozambique that have been previously drier than average.
NCEP/GFS Precipitation Forecasts
Total Anomaly
Forecasts from 19 Apr 2010 – Days 8-14
For Days 8-14 (26 Apr – 2 May 2010), showers are forecast to diminish across eastern croplands of southern Africa.
Forecast Verification: Southern Africa
Total
Anomaly
Forecast from 5 Apr 2010 Valid 12 – 18 Apr 2010
Forecast from 12 Apr 2010 Valid 12 – 18 Apr 2010
Observed 12 – 18 Apr 2010
Anomaly Anomaly
Total Total
Image not available
Image not available
Brazil & Argentina
• Rainfall Total & Anomaly Patterns• Temperature Patterns• GFS Forecast
Rainfall Total & Anomaly Patterns:Last 7 Days
Total
Argentina
Brazil
Anomaly•A large area of dry weather overspread most of Brazil’s primary corn and soybean regions, with rainfall limited well to the north.
•Dryness observed across Brazil spread southward into northeastern Argentina. Isolated thunderstorms were observed across Santiago del Estero and the lower Parana River Valley.
Rainfall Total & Anomaly Patterns:Last 15 Days
Total
Argentina
Brazil
Anomaly• Heavy rain across Brazil has been displaced far to the north during the previous two weeks, with large 15 day rainfall deficits observed across Brazil’s center west and southern croplands. Northwestern Rio Grande do Sul has received no rainfall during the past two weeks.
•In Argentina, below-average rainfall was observed across most states during the previous two weeks, with the highest deficits observed in northeastern Argentina.
Rainfall Total & Anomaly Patterns:Last 30 Days
Total
Argentina
Brazil
Anomaly• Across Brazil, heavy rain fell early in the period across the Brazilian Plateau region (primarily Mato Grosso and parts of Goias), but increasing dryness was noted further south, particularly across Rio Grande do Sul.
•Across Argentina, mostly below-average rainfall accumulations prevailed over the previous 30 days.
Recent Evolution: RainfallLast 30 Days
• Time series across South America depict 30 day accumulations near average in Brazil, but note the significant ahead-of-trend dryness over the past 15 days in central and southern Brazil. Below-average rainfall was observed in northern Argentina.
ClimatologyRainy Season Dates
DEMISE
The South American rainy season ends from southeast to northwest across much of southeastern and south-central Brazil during late April. The lack of rain during the previous two weeks in central Brazil indicates that a retreat of the rainy season is occurring several weeks early.
Temperature (°C) - BrazilBased on GTS Stations (no QC)
Extreme Minimum
Anomaly
Extreme Maximum Mean
Temperatures over the previous week were near to above-average across Brazil.
Extreme Minimum
Anomaly
Extreme Maximum Mean
Temperature (°C) - ArgentinaBased on GTS Stations (no QC)
Temperatures were near average across Argentina’s primary croplands, with chilly weather observed across western arid regions and southern farmlands, though no freezes were recorded. Minimum temperatures fell as low as 2°C across portions of Buenos Aires and La Pampa.
NCEP/GFS Precipitation Forecasts
Total Anomaly
Forecasts from 29 March 2010 – Days 1-7
• For Days 1-7 (19 – 25 Apr 2010), the GFS forecasts very heavy rainfall across southern Brazil, including northern Rio Grande do Sul, which has been dry for the past several weeks. This rainfall is in association with a potent cold front pushing northward out of Argentina. Dry weather is forecast to continue across most of central Brazil, which is increasingly seasonable in southeastern croplands such as Minas Gerais, but an early end to the rainy season in Mato Grosso.
NCEP/GFS Precipitation Forecasts
Total Anomaly
Forecasts from 29 March 2010 – Days 8-14
• For Days 8-14 (5 – 11 Apr 2010), dry weather is forecast to return to Rio Grande do Sul with cooler temperatures, but frontal rains will continue further north in Parana and southern Minas Gerais. Dry, below-average weather is forecast to continue across central Brazil, including Mato Grosso and the northeastern interior croplands.
Forecast Verification: South America
Total
Anomaly
Forecast from 5 Apr 2010 Valid 12 – 18 Apr 2010
Forecast from 12 Apr 2010 Valid 12 – 18 Apr 2010
Observed 12 – 18 Apr 2010
Anomaly Anomaly
Total Total
Image not available
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USDA Crop Information
Major World Crop Areas and Climate Profiles
http://www.usda.gov/oce/weather/pubs/Other/MWCACP
Crop Calendars by Month
http://www.usda.gov/oce/weather/CropCalendars