The northern branch of the jet stream features a trough over Alaska and the polar vortex over northern Canada extending across Greenland. This is producing cool/cold temperatures over southern Canada. The southern branch of the jet features a trough in the Gulf of Alaska, a ridge in the eastern Pacific, a trough off the coast of California, a ridge over the western U.S., a trough over the north-central U.S., and a strong trough along and off the east coast of the U.S. Subtropical high pressure is centered over southern Mexico.
The operational run of the U.S. and European models are in good agreement through 7 days, fair agreement days 8-10. During the 6-10 day period the northern branch of the jet stream will feature a ridge over eastern Alaska and western Canada extending up towards the pole, a polar vortex over central and eastern Canada, and some weak ridging over Greenland. This will produce cold/very cold temperatures over most of Canada. The southern branch of the jet will feature a trough over the western Gulf of Alaska, a ridge in the eastern Gulf of Alaska, some weak ridging along and off the west coast of the U.S., a trough extending from the Rockies to the Midwest, and a ridge along and off the east coast of the U.S. Despite the fact that the trough has shifted further west into the central U.S., it appears the speed of movement of systems within this trough will limit precipitation in much of the central U.S. Only the southeast Midwest and Delta states could pick up some significant precipitation along the boundary zone between the cold air to the west and the warm air to the east, but this is uncertain. Temperatures will be on the mild side during the next 5-7 days but will be turning colder under the trough aloft during days 6-10.
This pattern will feature near to above normal temperatures in the Midwest during the next 6-7 days, cooling to below to much-below normal days 8-10.
Precipitation below normal during the next 7 days, near to below normal days 8-10. The Northern Plains will see mostly above normal temperatures during the next 5 days, below to much below normal days 6-10. Precipitation mostly below normal. The Southern Plains will see near to above normal temperatures during the next 6 days, near to below normal days 7-10. Precipitation below normal.
The Delta states will see near to above normal temperatures during the next 7 days, near to below normal days 8-10. Precipitation near to below normal.
DTN Senior Ag Meteorologist Mike Palmerino can be reached at email@example.com
NATIONAL TEMPERATURE/RAINFALL EXTREMES:
HIGH MON...86 AT PEMBROKE PINES FL
LOW MON...22 BELOW ZERO AT COTTON MN
24 HOUR RAINFALL ENDING AT 7 PM YESTERDAY…ALBANY NY 1.17 INCH
US OUTLOOK AND MODEL DISCUSSION 6-10 DAY PERIOD:
The U.S. and European models are in fair to good agreement during the first few days of the period, fair agreement towards the end of the period. The main features of the weather pattern will be the building ridge pushing northward through Alaska towards the Arctic Circle, which then leads to a deepening polar vortex dropping southward over Hudson Bay and then south of Hudson Bay during the first 3-4 days of this period. This suggests a turn to much colder weather over the Canadian Prairies and the north-central U.S. region, already hinted at on Monday's U.S. model. Precipitation chances are mainly ahead of the deepening polar trough and a much weaker southern trough tracking across the central Plains into the eastern U.S. The first couple of days of the outlook period could feature a considerable amount of precipitation from the lower Mississippi and Ohio valleys, eastward. The U.S. model operational run is drier than the European model over the Delta and in the southeast Midwest with the precipitation mostly in the eastern U.S. However, both the U.S. and European model mean maps from their ensemble runs feature above normal precipitation through the Delta and the Ohio river valley as well as through the northeast and east-central U.S. areas.
At the end of the period, days 9 and 10, the European model shows somewhat of a trailing upper level trough stretching westward across the Canadian Prairies. If real, this might limit the southward push of this very cold event late in the period. This means the central and Southern Plains and the southern Midwest may not be as cold towards day ten, using this model. The U.S. model does not show this tail on the main trough. This, then, allows the colder weather to penetrate further to the south than the European model would suggest.
The mean maps at 8-10 days show this high latitude blocking pattern along with a strong northwest Atlantic ridge. This suggests a dramatic shift to much colder weather will move south through central Canada into the central U.S. The north-to-south flow between the Alaska ridge and the Hudson bay low sends the cold Arctic air south. The Atlantic ridge limits the eastward movement of features suggesting the cold air moves more south than east during the period.
MAJOR WORLD HIGHLIGHTS/IMPACT:
NORTHERN PLAINS (CORN,SOYBEANS,LIVESTOCK): A mainly dry period lasting 7 to 10 days along with warmer temperatures lasting 5 days or so will help melt snow cover. However, low sun angle and length of day will considerable slow this process this time of the year. Improving conditions for livestock, until the next Arctic outbreak moves in later in the period. Little additional harvesting of corn or soybeans is expected this week.
CENTRAL/SOUTHERN PLAINS: Some beneficial rainfall for winter wheat during the past week. Although in southwest Kansas and southeast Colorado it remains too dry. No significant cold weather impacts are expected this week. However, next week we will need to watch the movement of the Arctic outbreak expected to hit the northern plains area late this weekend and early next week.
MIDWEST (CORN, SOYBEANS, WHEAT): Wet conditions due to recent rain, some heavy rain, delays the remaining harvest. Some corn may be left in the fields until spring. Any soybeans remaining in the fields may be lost. Some improvement is possible during the next 7 days or so as it looks drier, especially west and north areas.
BRAZIL (Soybeans/full season corn): Favorable conditions for developing soybeans throughout the major growing areas with beneficial rains last week.
Above normal temperatures and below normal rainfall continues to impact soybean planting and development in the minor northeast areas (Bahia).
ARGENTINA (CORN/SOYBEAN): Mostly favorable conditions for planting and early development of corn and soybeans in the major growing areas. However, a drying trend during the next 10 days will need to be watched as some locations have not received much rainfall recently. Dryness is especially evident over northern Buenos Aires due to less than 50 percent of normal rainfall during the month of November.
SOUTH AFRICA (MAIZE/SUGARCANE): Another hot, dry day yesterday in both maize and sugarcane areas. Today is looking fairly hot and mostly dry as well. After that increasing shower activity and cooler temperatures can be expected, especially late this week or during this coming weekend. If verified this would help ease stress to crops caused by the recent heat wave in the area, during the past 5-7 days.
AUSTRALIA (SORGHUM/COTTON/SUGARCANE): Showers have been in key growing areas for sorghum and cotton during the past week while the sugarcane areas remained drier. The rainfall may favor development of the sorghum and cotton crops but it is not enough to ease drought conditions or to improve irrigation supplies.
Rainfall during the next 10 days likely averages below normal.
EXPANDED SUMMARIES FORECASTS:
Midwest (corn, soybean and winter wheat)
West: Mostly dry during the past 24 hours. Temperatures averaged below normal north and central areas, near normal south.
East: Dry or with only a little very light precipitation yesterday.
Temperatures averaged above normal for the morning lows, mostly below normal for the afternoon highs.
West: Mostly dry today through Thursday. Temperatures average above normal today and Wednesday, near to above normal Thursday.
Mostly dry Friday and Saturday. Dry or with only a little light precipitation developing during Sunday or Sunday night. Temperatures average near to below normal Friday, above normal Saturday and Sunday.
East: Mostly dry today and Wednesday. Dry or with only a little light precipitation in southern most areas Thursday or Thursday night. Temperatures average near to above normal northwest and below normal southeast today, near to above normal tomorrow and Thursday... coolest east areas.
Mostly dry Friday and Saturday. Light precipitation favoring southern and eastern areas during Sunday or Sunday night. Temperatures average near to below normal north and near to above normal south Friday, near to above normal west and below normal east Saturday, above normal Sunday.
6 to 10 day outlook: Temperatures are expected to average above normal Sunday, above normal south and east and below normal northwest Monday, below normal west and near to above normal east Tuesday, below normal Wednesday and Thursday. Precipitation near to above normal south and east, near to below normal northwest.
Northern plains (Corn, Soybeans, Spring Wheat)
Summary: Mostly dry. Temperatures averaged above normal through west and central areas and below normal east.
Forecast: Mostly dry today through Thursday. Temperatures average above normal today and Wednesday, near to above normal Thursday.
Mostly dry Friday and Saturday. Chance for light snow or snow showers during Sunday. Temperatures average near to below normal south and east and above normal northwest Friday, above normal Saturday, below normal north and near to above normal south Sunday.
6 to 10 day outlook: Temperatures are expected to average below to well below normal during this period, coldest central and east areas. Precipitation near to below normal.
Central and Southern Plains (Winter Wheat/livestock)
Summary: Mostly dry during the past 24 hours. Temperatures near to below normal.
Forecast: Mostly dry today and Wednesday. Scattered light precipitation, favoring southeast and south-central areas, during Thursday. Temperatures average near to above normal today and Wednesday, above normal south and east and near to below normal northwest during Thursday.
Mostly dry Friday through Sunday. Temperatures average mostly near normal Friday, above normal Saturday and Sunday.
6 to 10 day outlook: Temperatures are expected to average above normal Sunday, above normal south and east and near to below normal northwest Monday, near to mostly below normal Tuesday through Thursday. Coldest north and east areas Tuesday through Thursday. Precipitation near to below normal during this period, except possibly near to above normal in southeast areas.
Rio Grande do Sul and Parana…
Summary: Mostly dry during the past 24 hours. Temperatures near to below normal south, near to above normal north.
Forecast: A few sprinkles or light showers mainly in Parana today. Light to moderate showers from northwest RGDS to Parana tomorrow. Showers may linger in Parana during Thursday. Temperatures average near normal today and Wednesday, near to below normal Thursday.
Mostly dry Friday through Sunday. Temperatures average below normal Friday, near to below normal Saturday, near normal Sunday.
Mato Grosso, MGDS and southern Goias...
Summary: Scattered to widely scattered light and moderate showers during the past 24 hours. Temperatures ranging from a little above to a little below normal.
Forecast: Scattered to widely scattered showers and thundershowers today.
Scattered showers during Wednesday and Thursday may tend to favor eastern Mato Grosso and Goias. Dry or with only a few light showers elsewhere in the region during this time. Temperatures average near normal south and west and above normal northeast today, above normal through northwest and central Mato Grosso tomorrow and Thursday, near normal elsewhere in the region during this time.
Scattered showers will tend to favor north and east areas Friday and Saturday. Scattered showers and thundershowers during Sunday. Temperatures average near to below normal Friday, near normal Saturday and Sunday.
Argentina Corn and Soybeans…
Cordoba, Santa Fe, north Buenos Aires...
Summary: Dry or with only a few very light showers in western areas yesterday.
A few thundershowers have moved into south and west areas during the night.
Temperatures averaged near to below normal yesterday.
Forecast: A few showers and thundershowers favoring south and west areas today and tonight. Drier during Wednesday. Dry Thursday. Temperatures average near to below normal today, below normal tomorrow, near to below normal Thursday.
Mostly dry Friday. Dry or with only a few light showers Saturday. Mostly dry Sunday. Temperatures average near to above normal Friday and Saturday, above normal Sunday.
Joel Burgio can be reached at firstname.lastname@example.org
© Copyright 2019 DTN/The Progressive Farmer. All rights reserved.