DTN Ag Weather Brief

METEOROLOGICAL DISCUSSION

The northern branch of the jet stream features a weak trough over Alaska. A weak ridge over northwest Canada. A trough over north-central Canada, A trough over eastern Canada. And a weak riidge over Greenland. This is a cold pattern for much of Canada. The southern branch of the jet features a trough along and off the west coast of the U.S. A flat ridge over the Rockies, Plains and western Midwest and a trough over the eastern US and western atlantic. Subtropical high pressure is centered off the northwest coast of Mexico.

EXTENDED OUTLOOK

The U.S. and European models are in good agreement through 6 days, fair-poor agreement days 7-10. We are leaning more towards the U.S. model. During the 6-10 day period the northern branch of the jet will feature a strong ridge between Siberia and Alaska. The polar vortex over Alaska and western Canada and a ridge over eastern Canada and Greenland. This will be a cool/cold pattern for western and central Canada, variable in the east. The southern branch of the jet will feature a trough in the eastern pacific/Gulf of Alaska and a low to moderate ampliture jet with embedded disturbances across the U.S. Guidance implies a mean ridge over the interior western US and a mean trough over the eastern U.S. and western atlantic. Disturbances will eject eastward from the trough in the Gulf of Alaska moving rapidly eastward across the U.S. in the strong west to east flow. The quick movement of systems combined with some ridging in the southern U.S. will limit precipitation in the central US. However guidance continues to indicate these disturbances may slow enough to produce some significant rainfall in the eastern Midwest. Temperatures will be variable. Milder out ahead of systems, cooler behind them.

This pattern will feature variable temperatures in the Midwest. Precipitation below normal during the next 5 days. Near to below normal west, near to above normal east days 6-10. The northern Plains will see variable temperatures. Precipitation below normal. The southern Plains will see variable temperatures. Precipitation below normal. The Delta states will see near to above normal temperatures. Rainfall below normal.

Mike Palmerino

NATIONAL TEMPERATURE/RAINFALL EXTREMES:

HIGH THU...86 Organ Pipe Cact and Davis-Monthan AFB AZ LOW THU...11 BELOW ZERO AT 13 MILES NORTHEAST OF POPLAR MT AND BOTTINEAU ND

24 HOUR RAINFALL AT 7PM YESTERDAY...COLUMBUS GA 1.39 INCHES

US OUTLOOK AND MODEL DISCUSSION 6-10 DAY PERIOD:

The US and European models are in only fair agreement during the outlook period. I favor today's US model.

The period will begin with much of the central and eastern US back to above normal temperatures with little precipitation activity. A short wave trough is expected to move west to east near the US/Canadian boarder across the northern Rockies and the northern plains through the Great Lakes region and over the northeast US. This system is shown deepening as it moves over the Great Lakes region next Friday. This may mean a significant storm mostly in Ontario and Quebec Canada but possibly through northeast areas of the Midwest. Colder weather moves south behind the departing storm first into the northern plains and then into the Midwest region. Late in the period it may begin to warm again as the trough is in the east and weakening. A peak at the 11 to 16 day period today suggests that colder weather would return to the Midwest region during the week of Nov 20 to 24, but this is uncertain at that time frame.

The European model, if it were to verify instead, is slower with the short wave trough, further west and a little further south when the system begins to deepen. If real this opens the door to potential stormy weather for the northeast plains, the northwest Midwest and Manitoba Canada and pushes the colder weather to the end of the period as well.

The mean maps at 8-10 days continue to feature a strong high latitude blocking ridge centered southwest of Alaska. We also note a weaker high latitude ridge over northeast Canada and Greenland. This second high has been slowly building during recent days. This serves to force the jet stream southward over the eastern US and is the reason for the below normal heights depicted across the northern plains and the Midwest region on the European model and over the eastern Midwest and the northeast US region on the US model.

This southward displacement of the jet stream and the deepening trough under the northeast ridge would mean a colder trend a for the north and central US areas. Bias this period is in the northeast using the US model and the north plains and Midwest using the Euro.

MAJOR WORLD HIGHLIGHTS/IMPACT:

MIDWEST (CORN/SOYBEANS): Drier weather during the next 5 days, along with warmer temperatures for the last part of the period, will favor harvest activity in the Midwest region. Longer range we will need to deal with potential for unsettled weather and cold snaps but this is not until the end of next week and next weekend.

CENTRAL/SOUTHERN PLAINS (WHEAT, LIVESTOCK): Favorable conditions for developing winter wheat at this time. A colder trend continues today before warmer weather redevelops. Soil moisture due to early season rainfall will favor crop development. However, a drying trend in the region does bear watching as we head into the winter dormancy period.

BRAZIL (SOYBEANS, CORN): An improving rainfall pattern for planting and developing soybeans in central Brazil after earlier hot, dry weather.

A break in the rainy pattern over southern areas may help improve conditions for planting and early development during the coming days, cool at first and then warmer to hotter.

ARGENTINA: Mostly favorable conditions at this time for planting and development of corn, soybeans and sunflower and for developing winter wheat.

However, some wet weather in southern growing areas may slow planting progress at times in key sunflower areas. Hot temperatures from Sunday through Tuesday are not overly concerning at this date, except they will serve to reduce available soil moisture somewhat.

SOUTH AFRICA (MAIZE): A recent turn to hot, dry weather in the region may mean delays to planting progress for western growing areas and increasing stress to germination and early development of maize in the east. A weak cold front moves through today and Saturday with a few showers and less hot weather likely. A strong cold front is projected for the region next Tuesday into Wednesday with the chance for heavier thunderstorms and significantly cooler temperatures.

EXPANDED SUMMARIES FORECASTS:

Midwest corn, soybean and winter wheat

Summary...

West: Mostly dry. Temperatures below normal.

East: Dry or with only light snow in far northeast areas yesterday.

Temperatures below normal north and west, near normal southeast.

Forecast...

West: Mostly dry today. Dry or with only a little light precipitation favoring eastern and southern areas Saturday. Dry Sunday. Temperatures average well below normal today, near to above normal west and below normal east Saturday, near normal Sunday.

Mostly dry Monday. Dry or with only a few light showers with locally heavier Tuesday, favoring eastern and southern areas. Mainly dry Wednesday.

Temperatures average above to well above normal during this period.

East: Snow squalls east of Lake Michigan today, dry elsewhere in the region today. Mostly dry Saturday. Dry or with only a little light precipitation during Saturday night or during Sunday. Temperatures average below to well below normal today and early Saturday, somewhat warmer later Saturday, near to below normal during Sunday.

Mostly dry Monday and Tuesday. Scattered light to locally moderate precipitation during Wednesday. Temperatures average near to above normal Monday, above normal Tuesday and Wednesday.

6 to 10 day outlook: Temperatures are expected to vary somewhat during this period. Precipitation should average near to below normal west, near to above normal through east areas..especially northeast areas.

Central/Southern Plains (Wheat, livestock)

Summary: Mostly dry. Temperatures below normal.

Forecast: Mostly dry today through Sunday. Temperatures average below normal today, above normal Saturday, near to above normal Sunday.

Mostly dry Monday and Tuesday. Dry or with only light showers in extreme east areas Wednesday. Temperatures average above normal during this period.

6-10 Day Outlook: Temperatures are expected to average above to near normal during this period. Rainfall should average below normal.

Brazil...Mato Grosso, MGDS and Goias (Soybeans)

Summary: A few light showers with isolated heavier in north and east areas during the past 24 hours. Little elsewhere in the region. Temperatures averaged above normal in Mato Grosso, near to below normal elsewhere in the region.

Forecast: Scattered to widely scattered light to moderate showers and thundershowers today. Showers may linger in the north and east areas Saturday.

Dry Sunday. Temperatures average near to above normal today, somewhat cooler during the weekend.

Scattered showers may occur in northern Mato Grosso and northern Goias during the period Monday through Wednesday. However, much of the region looks to be drier. Temperatures near to below normal early in the period, warmer later.

Brazil...Parana, Santa Catarina, Rio Grande Do Sul (Corn, Soybeans)

Summary: Mostly dry or with only isolated shower activity yesterday. Overnight a few scattered showers have moved over RGDS. Temperatures averaged near normal yesterday.

Forecast: Scattered light to moderate showers and thundershowers today. Drier tomorrow. Dry Sunday. Temperatures turn cooler during this period.

Mostly dry Monday through Wednesday. Temperatures trend somewhat hotter during this period.

Central/South Argentina: Cordoba, Santa Fe, Buenos Aires, La Pampa (Corn, Soybeans, Sunflower, Winter Wheat)...

Summary: Scattered thundershowers were reported in western most crop areas during the past 24 hours. Little elsewhere in the region. Temperatures averaged mostly near to slightly above normal.

Forecast: Mostly dry today through Sunday. Temperatures turn warmer today and Saturday, hot weather during Sunday.

A few light showers may occur in southern areas Monday, dry elsewhere in the region. Light to moderate showers south, fair north, Tuesday. Dry or with only a few light showers moving through during Wednesday. Hot Monday and Tuesday with highs ranging from the upper 80s to the middle 90s f (31-36c), somewhat cooler Wednesday.

(SK)

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