Climate outlook for Belg 2013

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CLIMATE OUTLOOK

FOR BELG 2013

National Meteorological Agency (NMA)

February 1, 2013



Outline

• Introduction

•Climate of Belg season

• Analogue years and spatial rainfall patternsunder selected analogue years

•Current and future seasonal trends

•Climate outlook for Belg 2013



Introduction to Belg season

• Belg is the period from mid February to May• It is the main rainy season for south and southeast

regions

• Belg, the starting season for long rainy season

• April, the major rainy month for the period of Belg

• Belg has strong intra-seasonal rainfall variability• During Belg day time temperature attains its

maximum peak point



Climate of Belg Season



During the last four weeks, equatorial SSTs were above average

across the western Pacific Ocean, the western Indian Ocean,

and the eastern Atlantic Ocean. SSTs were below average in the

east-central and eastern Pacific Ocean.

SST Departures (°C) in the Tropical Pacific

During the Last 4 Weeks



Recent Evolution of Equatorial Pacific SST Departures (oC)

Longitude

Time

From June – October 2012, above-

average SSTs were evident acrossmost of the equatorial PacificOcean.Recently, below-average SSTs inthe eastern Pacific have expandedwestward.



The latest weekly SST departures are:

Niño 4 0.0°C

Niño 3.4 -0.2°C

Niño 3 -0.5°CNiño 1+2 -0.6°C

Niño Region SST Departures (°C) Recent Evolution



Sub-Surface Temperature Departures (°C) in the Equatorial Pacific

• In the last two months, negativesubsurface temperature anomaliesshifted eastward across theequatorial Pacific.• Recently, negative subsurface

temperature anomalies, associatedwith an upwelling Kelvin wave, haveshifted into the eastern Pacific.

Time

Longitude Most recent pentad analysis



Weekly SST Departures (°C) for the Last Four Weeks

The change in SST anomalies is negative across the eastern

half of the equatorial Pacific



Global and regional indicators• ENSO-neutral conditions continue.

• Equatorial sea surface temperatures (SST) are near

average to below average across the Pacific Ocean.

• Some atmospheric circulation features resemble La

Niña, but this is at least partially due to an active

Madden-Julian Oscillation (MJO).

• ENSO-neutral is favored for Northern Hemisphere

winter 2012-13 and into spring 2013.

• Warm SST over east and west African Coast as well

as north and central Atlantic.

• Negative SST anomaly over equatorial Atlantic

Ocean, Mascarene area.

Summary Current Global and Regional SST status



-1.5

-1

-0.5

0

0.5

1

1.5

2

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

1977-1978

1979-1980

1994-19952002-2003

2004-2005

2006-2007

2012-2013

Analogue years

Best Analogue Years: 2007, 1978 and 2005



Summary Analogue years and spatial rainfall

patterns under selected analogue years

•Normal onset, normal spatial and temporaldistributions of the seasonal rains

•The seasonal rainfall activity was relatively

enhanced during some of analogue years•Near normal seasonal rainfall patterns

occurred over the major Belg growing

areas in much of analogue years•Dry spell occurred during major seasonal

rainy months in some of analogue years.



Current and future seasonal trends



Summary Current and future seasonal trends• High likelihood of neutral ENSO conditions enduring

through the first quarter of 2013, with probabilities of El

Niño or La Niña each less than 30% through northern

summer 2013.

• Most of the set of dynamical and statistical model

predictions issued during late December 2012 and early

January 2013 predict neutral ENSO conditions, with only acouple of models predicting weak El Nino conditions by

spring 2013, and one predicting weak La Nina conditions

for the coming 1 to 2 seasons.

• As of mid-January, 8% of the set of dynamical andstatistical models models predicts La Niña SST conditions

for the Jan-Mar 2013 season, none predict El Niño

conditions, and 92% indicate neutral ENSO conditions. For

Feb-Apr and Mar-May, 4% indicate La Niña conditions and96% indicate neutral ENSO conditions.



Summary Climate outlook for Belg 2013• Near normal onset and cessation are expected over much portions of

the country.

• Normal to below normal rains are expected over much of northeastern portions of the country

• Moreover, below normal rainfall is expected to be more pronouncedover southeastern region, where Belg is the major rainy season.

• Near normal Belg rain is most likely to prevail across central,easternand southern regions

• Close to normal tend to above normal rainfall is anticipated over northwestern and western parts of the nation.

• The seasonal rainfall activity is anticipated to be getting better duringMay.

• The maximum temperature is expected close to normal over much of the nation despite the fact that, it is likely to be slightly above normalacross lowlands of the country.

• In general, the seasonal rain will be close to normal over the westernhalf, while below normal rainfall will dominate major portions of Belgrain benefiting regions. Moreover, the anticipated Belg rains will bebetter than last year’s Belg season.



Extended Climate Outlook for Kiremt 2013

Current and projected regional and globalmeteorological phenomena will be in favor of seasonal rains in the upcoming Kiremt 2013season. However, as the predictability skill is very low during this time of the year, the users are kindly advised to use NMA’s updated version of the forecast.



THANK YOU FOR YOUR

ATTENTION!

Climate outlook for Belg 2013

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