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Scott A. Yuknis High impact weather forecasts, climate

assessment and prediction. 14 Boatwright’s Loop Plymouth, MA 02360

Phone/Fax 508.927.4610 Cell: 508.813.3499

ClimateImpact@comcast.net

Climate Impact Company Global Agriculture Sunday Report

Issued: Sunday, August 20, 2017

Highlights

United States: Iowa drought reaches extreme level

India: Presence of MJO enhances heavy rainfall events well into September

Europe: Southeast Europe drought worsens

Ukraine: Showery this week and again 11-15 day period

China: Frequent thundershowers across wheat areas

Australia: Highly changeable temperature pattern and limited rainfall

So. America: More heavy rain in northeast Argentina in the 6-10 day period

Pictured: Although no formal El Nino occurred in 2017 the multivariate ENSO index indicates a

farily strong El Nino climate the past 3 months.

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United States: Last week the drought conditions in south-central/southeast Iowa

which is in the heart of soybeans and corn reached “extreme” levels according to

USDA (Fig. 1). There is some short-term relief indicated tomorrow as severe

thunderstorms pass and cause potentially 1-2 in. of rain (Fig. 2). After tomorrow

forecast models off limited conviction on producing rainfall for this region

therefore the drought condition certainly persists but is not likely to worsen as

temperatures are generally cooler than normal.

Fig. 1: The south-central/southeast Iowa drought is now extreme.

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Fig. 2: The south-central/southeast Iowa drought is now extreme.

India: Excessive rainfall associated with tropical rainfall events continue to plague

parts of India. This week excessive rainfall occurs in southwest India and the

central southeast coastal areas. Most of the excessive rainfall is to the south of

wheat growing areas. The rainfall is caused by presence of the Madden Julian

oscillation (MJO) in the Indian Ocean. The 15-day rainfall forecast is likely not

wet enough as the MJO stays in the Indian Ocean.

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Fig. 3: The 15-day percent of normal rainfall forecast across India is indicated.

Europe: Thundershowers bring areas of heavy rain to Southeast Europe caused by

a cold front MON/TUE. The rainfall is not widespread enough to turn the drought

condition in that area. Once we’re past Tuesday operational models indicate no

additional rainfall in Southeast Europe through the next 15 days (Fig. 4) with

gradually regenerating anomalous heat (Fig. 5).

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Fig. 4: Anomalous heat returns to Southeast Europe in the 6-10 day period.

Fig. 5: Anomalous heat (and dryness) continues days 11-15 in Southeast Europe.

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Ukraine: Needed rainfall caused by an upper trough and slow-moving cold front

affects the Ukraine early this week (Fig. 6). However, the drier pattern returns

days 6-10 across southern Ukraine and all of the Black Sea region (Fig. 7). During

the 6-10 day period central and west Europe turn wet. The 11-15 day period

identifies the west pattern in Central Europe days 6-10 shifting eastward (Fig. 8)

but still leaving the Black Sea region and southern Ukraine drier than normal.

Fig. 6-8: The GFS OP day 1-5, 6-10 and 11-15 percent of normal rainfall forecast

on Ukraine, Black Sea region and Southwest Russia.

China: Heavy rainfall is indicted (at times) across the wheat growing areas in

northeast China over the next 15 days. The first opportunity is this week followed

by a drier day 6-10 forecast and followed by more rainfall in the 11-15 day

forecast. Models are not in complete agreement therefore the outlooks are made

with below average forecast confidence. Across China temperatures are generally

hotter than normal to the south of a wide area of unusually cool weather in

Mongolia and central/east-Central Russia (Fig. 9).

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Fig. 9: The 15-day temperature outlook across eastern Asia identifies a dividing

line between chilly temperatures in Russia/Mongolia and a hotter regime across

China. Along the dividing line is an active thunderstorm pattern.

Australia: Exceptional changeability to the Australia climate pattern is indicated

during the next 15 days. This week anomalous heat is centered on the northwest

continent while averaging near normal across southeast Australia (Fig. 10). Some

beneficial rainfall is likely for coastal Southeast Australia south of the agriculture

belts. A sharp cold front brings limited rainfall but a drastic change in temperatures

during the 6-10 day period (Fig. 11). During that time cooler temperatures surge

into northeast Australia while far western sections remain quite warm. As quickly

as the cool pattern emerges during late August, a warmer than normal climate

returns in the 11-15 day period strongest in southwest portions (Fig. 12). Despite

the changeable weather pattern a change in the Australian drought condition is not

expected.

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Fig. 10-12: The temperature anomaly forecast across Australia for days 1-5, 6-10

and 11-15 are indicated.

South America: Volatility is projected in the South America percent of normal

rainfall forecast through the next 15 days. This week is dry across most of

Argentina and Brazil (Fig. 13). However, excessive rainfall is likely ahead of 2

cold fronts in the 6-10 day period affecting Bolivia to Uruguay and northern

Argentina (Fig. 14). In the 11-15 day period the changeable forecast indicates

weak high pressure and a drier pattern (Fig. 15).

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Fig. 13-15: The precipitation anomaly forecast across South America for days 1-5,

6-10 and 11-15 are indicated.