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| Field Crop Advisory Team Alert newsletter | |||||||
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| Vol. 23, No. 18, September 18, 2008 |
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| In this issue Check summer seeded alfalfa in a few weeks to determine potential root rot damage to the new stands Fall forage management for hay and pasture Reducing soybean harvest losses Fall wheat fertilization Are your soils compact? Soybean production and management information resource Grain moisture measurements may divert mold and insect infestation Custom machine rates guide Web links to articles on corn harvesting Employee dismissal Regional reports Weather |
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| Final issue for 2008 This is the last issue for the 2008 season of the Field CAT Alert newsletter. Included in this issue is an index of articles to help guide readers through the topics covered this year. Educators and specialists have worked hard to inform readers about current issues and crop production throughout the last few months. Now we would like to hear from you! Please send us suggestions on topics that you would like us to cover in 2009. Take our survey at to let us know how you are benefitting from the newsletter and to give us feedback on improvements for the print publication and web site. Please send your comments via catalert@msu.edu or mail them to the address on the back of this newsletter. Indicate whether you are referring to our fruit, vegetable, field or landscape edition. Thank you. -Joy Landis, editor, Andrea Buchholz, asst. editor, Victoria Morris, associate editor |
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| Check summer seeded alfalfa in a few weeks to determine potential root rot damage to the new stands Because of excessive rainfall in many areas of Michigan this past week, many newly seeded alfalfa fields may show poor growth in wet or poorly drained fields which may be due to several diseases. Seedling diseases should be suspected when emergence is poor or there are stunted, discolored, or dead seedlings. Aphanomyces root rot can cause death and stunting of seedlings as well as more subtle disease of established plants that can result in significant yield reduction. This disease is caused by a soilborne fungal-like pathogen. Other diseases that occur in wet or poorly drained soils include Phytophthora root rot and Pythium seed and root rot. Plants infected with Aphanomyces usually become stunted and chlorotic (yellow) before they wilt and die, whereas Phytophthora and Pythium tend to kill seedlings quickly before plants become severely chlorotic. Another clue to a problem with Aphanomyces is root rot of an alfalfa cultivar that is highly resistant to Phytophthora. Although not much is known about Aphanomyces root rot in Michigan, it is known to be a serious problem in nearby states including Wisconsin, Indiana, and Iowa. We suspect this disease is also a problem in some Michigan fields. Perhaps because alfalfa disease that occurred in wet soil was attributed to Phytophthora, Aphanomyces root rot of alfalfa was not recognized as a serious problem until the early 1980s. Aphanomyces root rot is best managed by avoiding poorly drained soils and using Aphanomyces-resistant alfalfa varieties. However, this past week, even well drained fields have been water-saturated due to abnormally high rainfall in the past few days. Fungicides are not available for control of Aphanomyces root rot of alfalfa. Phytophthora and Pythium root rots of seedlings can be controlled with fungicidal seed treatments, such as Allegiance-FL, Apron-XL, or Apron-FL, but these seed treatments are not effective against Aphanomyces. Alfalfa varieties rated highly resistant (HR) or resistant (R) to Aphanomyces root rot should be planted where slowly drained soils occur and where Aphanomyces may be a problem. A list of varieties and their disease resistance can be found at the Michigan State University Forage Information Systems web site at http://www.msue.msu.edu/fis/ and clicking on the Extension bar and then the Perennial Forage Legume and Grass Varieties for Michigan. Control of Aphanomyces root rot became more challenging when different races of this pathogen were discovered. Many commercial alfalfa cultivars are now available that have resistance to race 1, the first race discovered. Another race (race 2) of Aphanomyces was identified in the early 1990s that overcomes race 1 resistance. Alfalfa cultivars developed for resistance to race 1 are killed by the aggressive race 2 isolates. Race 2 isolates have been identified in a number of states including Wisconsin, Iowa, and Kentucky. Race 2 has not yet been confirmed in Michigan. Alfalfa varieties with resistance only to race 1 may be genetically vulnerable to Aphanomyces root rot in many regions due to the presence of race 2. Several commercial alfalfa varieties are now available that have resistance to both races of Aphanomyces. If resistance to race 2 is not specified for an Aphanomyces-resistant alfalfa cultivar, then you can assume it is resistant only to race 1. The overall distribution and impact of races 1 and 2 of Aphanomyces are uncertain, but Aphanomyces root rot should be considered as a potential problem in many parts of Michigan. If you have an alfalfa seeding that has failed this fall due to the excessive rainfall this past week, it should be safe to replant with alfalfa again next spring since compounds which cause autotoxicity do not accumulate in seedlings. Phytophthora- and Aphanomyces-resistant varieties (treated with Apron XL) are recommended for replanting failed seedings. Spring alfalfa re-seeding should be done as early as possible in the spring. For a photo of Aphanomyces symptoms on alfalfa, please look at this issue online at: http://www.ipm.msu.edu/cat08field/fc09-18-08.htm http://www.ent.iastate.edu/imagegal/plantpath/alfalfa/aphanomyces/0093.7aphansymp.html |
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| Fall forage management for hay and pasture Among the four seasons, fall is one of the most important seasons in terms of preparing for winter survival and spring regrowth by storing carbohydrate and protein reserves in the crowns and roots. Fall is also the season for regeneration and the formation of the shoots or growing points. Since plants become dormant in the fall as air temperature is getting lower and day length is shorter, nutrient uptake becomes accordingly slower. The following are things to consider for fall forage management for hay and pasture: 1) Soil fertility and liming: Since the price of fertilizer is so high these days, it’s important to use phosphorus (P) and potassium (K) efficiently. One of the best ways to save fertilizer costs is to test soil phosphorus and potassium on the hay fields and pasture. In particular, potassium is directly related to winter survival rate and it’s more susceptible to winter kill when soil potassium level is lower than the optimum level. 2) Fall harvest management of alfalfa: In the late summer and early fall, alfalfa must either be cut early enough so it can regrow and then replenish root carbohydrates and proteins, or so late that the alfalfa does not regrow more than eight inches and use root carbohydrates. This has resulted in the recommendation in Michigan of a “no-cut” window beginning in September and lasting until the killing frost. However, recent research in Quebec, Canada has helped to redefine this window by assuming that if 500 growing degree days accumulate after the last cutting, there will still be enough regrowth of alfalfa for good carbohydrate accumulation before a killing frost and good winter survival and yield the following year. So a producer can cut in September without hurting the stand as long as there is enough warm weather remaining in the growing season (accumulation of 500 growing degree days) before a killing frost. These growing degree days are calculated as the average of the daily minimum and maximum above 41°F until a killing frost of 25°F. The Quebec research also showed that cutting later in the fall was acceptable as long as less than 200 growing degree days accumulated after cutting. When less than 200 growing degree days accumulated, there would be little regrowth to use up valuable stored carbohydrates and proteins in the alfalfa roots. This would result in good winter survival of the alfalfa plants. For additional information including probability graphs of late summer growing degree days for your area in Michigan, check out the following web site: http://www.ipm.msu.edu/cat08field/pdf/9-18LateSummer.pdf |
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| Reducing soybean harvest losses Reducing harvest losses is a simple and effective way to increase soybean yields and profitability. Losses of 10 percent are typical and can reach 15 percent. With careful maintenance and operation, harvest losses can be maintained at three percent. Reducing harvest losses from 10 to three percent in a 45 bushel per acre soybean crop will increase the marketable yield by 3.1 bushels per acre. With market prices projected to be around $12.00 per bushel, this translates into more than $36.00 per acre of additional income. Harvest timing Properly timing your harvest operations is critical to reducing harvest losses. Harvest operations can begin any time after the beans have initially dried to 14 to 15 percent moisture. Depending on weather conditions, this is usually about five to 10 days after 95 percent of the pods have reached their mature color. Try to harvest as much of your crop as possible before the moisture level falls below 12 percent to reduce splits and cracked seed coats. Shatter losses have been shown to increase significantly when seed moisture falls below 11 percent and when mature beans undergo multiple wetting and drying cycles. Shatter losses can be reduced by harvesting in the morning or the evening when relative humidity is higher. Equipment maintenance Before harvest operations begin, inspect and repair the cutting parts on the header. Make sure that all knife sections are sharp and tight. Check the hold-down clips to ensure that they hold the knife within 1/32 of an inch of the guards. Adjust the wear plates to the point that they lightly touch the back of the knife. Consider switching to quick cut knives if the existing knife sections need replacing or if shatter losses have been high. Equipment adjustment Information from the University of Arkansas shows that a skilled combine operator can add more than $150 per hour in additional profits over an inexperienced operator or one that is trying to hurry or cut corners. Despite this, statewide surveys indicate that only 10 percent of combine operators check their combine adjustments regularly and match forward speed to field conditions. Combine operators should understand how losses occur and how to make the proper adjustments. Nearly 80 percent of harvest losses occur while cutting and gathering the plants into the combine. Most of these are due to shattering. The following recommendations will reduce gathering losses:
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| Fall wheat fertilization Planting time fertilization of wheat is very important for phosphorus and potassium nutrition of the crop. Having adequate phosphorus and potassium available for fall growth is important for root system development, winter survival and tillering of the plants in the spring. A 100 bushel per acre wheat crop removes 63 lbs P2O5 and 37 lbs K2O in the grain. And each ton of straw contains 13 lbs P2O5 and 23 lbs K2O. Therefore, a 100 bu/a wheat crop with two tons of straw per acre removed will remove 76 lbs P2O5 and 60 lbs K2O per acre. Be sure to soil test to determine the available level of phosphorus and potassium in the soil. Generally, no yield benefit occurs from applying phosphorus when the soil test value is above 25 ppm. Below this value, wheat yield may be improved by applying the recommended amount of phosphate. The critical potassium soil test ranges from 85 ppm in sandy soils to 125 ppm in clay loam soils. Above these values yield benefit does not usually occur from K application. Below the critical value applying recommended amounts of potash may improve crop wheat. Even when soil levels of phosphorus and potassium are adequate, applying 25 lbs each of P2O5 and K2O per acre along with 25 lbs N/a will insure good fall root establishment and plant vigor. Studies in Ontario have indicated that application of phosphorus and potassium in bands near the seed at the time of seeding the wheat increased the potential for producing top yields as compared to broadcasting. When soil phosphorus and potassium levels are within 15 to 20 ppm above the critical level, it is good to apply maintenance amounts, equal to crop removal, of phosphorus and potassium if financial resources permit. In an MSU study of the 2007 - 2008 growing period, various combinations of phosphorus, potassium, and sulfur broadcast just prior to seeding did not improve wheat grain yield over applying only nitrogen even though the soil potassium level was below the critical value. Including copper, manganese and zinc had no effect on yield. Most of the nitrogen is usually applied for wheat in the spring prior to green up. Slow release nitrogen fertilizers now in the market place make it possible to apply more nitrogen in the fall prior to seeding with minimal concern for loss. In nitrogen studies conducted in 2005 through 2007 (harvest year) wheat yields with broadcast-incorporation of nitrogen as polymer coated urea (ESN) in the fall resulted in grain yields equal to those produced with urea or UAN applied at the same rates just prior to green up in the spring. However, applying the ESN prior to green up resulted in the best yields, six to eight bushels more than fall applied ESN or spring applied urea or UAN. Slow release nitrogen materials provide another option for nitrogen management in wheat. |
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| Are your soils compact? With harvest operations comes trafficking over the fields by combines, tractors, wagons, grain carts, trucks etc. With trafficking comes soil compaction. The degree of compaction that occurs depends on soil moisture. Excessively wet soils will compact more than dry soils. The larger the tire, the deeper the compaction occurs. Compaction is most evident during harvest, but compaction may also have occurred during seedbed preparation. Chiseling or subsoiling can be done to help alleviate the effects of compaction, but prior to doing this find out at what depth the compact layer occurs. Studies have shown that chiseling two inches below the compaction zone or depth is very effective in breaking up the compaction layer. Chiseling deeper than this depth provides no additional benefit, and uses a lot more fuel. The presence of a compaction layer and the depth can be determined with a tile rod or even a soil probe when there is good soil moisture. An increase in resistance to pushing the rod in the ground is an indication of compaction. Some consultants may have a penetrometer to use that measures the actual resistance the rod encounters as it is being pushed into the ground. Probe the soil in several different spots in a field to determine whether or not compaction is a concern or the depth of compaction. Also, check the soil moisture at the depth of subsoiling. The soil should break apart when handled and not stick together in a clump when squeezed. If the soil is too wet, subsoiling will not be of benefit. The shanks should shatter the soil and not create a smeared channel. |
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| Soybean production and management information resource There is a great resource for soybean producers available at the Plant Management Network at the Focus on Soybean website. The site contains webcasts with PowerPoint slides narrated by university researchers from around the country, with presentations related to crop production, and crop protection. Topics include use of foliar applied fungicides for soybean in the North Central United States, choosing specialty soybeans for the right niche market, sudden death syndrome, soybean cyst nematode: biology, scouting and management and others. A sample webcast, Seedborne Pathogens of Soybean can be accessed at: http://www.plantmanagementnetwork.org/edcenter/seminars/SampleWebcast/ The soybean new section contains timely articles related to soybean production. One of the latest articles posted was written by Mike Staton, “Strategies Available to Help Soybean Growers Reduce Harvest Losses.” A subscription to Plant Management Network includes access to applied journals, pesticide trials, crop management variety trials and more. Subscriptions are $45 per year and can be ordered at : http://www.plantmanagementnetwork.org/Subscriptions/ |
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| Grain moisture measurements may divert mold and insect infestation Note: This article appeared on September 9, 2008 in Plant Health Progress Grain storage bins are routinely monitored for temperature to control insect and mold problems. Now an Agricultural Research Service (ARS) scientist and his colleagues at Kansas State University (KSU) have preliminary research findings showing that monitoring carbon dioxide, along with humidity and temperature, also may help detect problems more effectively. Grain moisture content and temperature are the primary factors affecting grain deterioration in storage. If these factors are not properly monitored and controlled, grain quality can deteriorate quickly due to mold growth and insect infestation. ARS engineer Paul Armstrong at the agency's Grain and Marketing and Production Research Center in Manhattan, Kansas, and Haidee Gonzales and Ronaldo Maghirang at KSU monitored a simulated grain storage bin during aeration to determine if high-moisture grain, or adverse storage conditions, in the bin top could be detected using sensors to measure relative humidity, temperature and carbon dioxide levels. Relative humidity and temperature can be used to estimate grain moisture, while carbon dioxide levels indicate the amount of respiration due, primarily, to molds. Current technology allows relative humidity and temperature sensors to be placed at multiple points within the grain mass. Carbon dioxide sensing is more feasible at an aeration duct. In the study, sensors were placed at different depths in the bin. High-moisture grain, comprising about 11 percent of the volume, was placed at the top of the bin and produced high amounts of carbon dioxide, which in most cases was easily detectable during aeration. Lowering grain temperature with aeration diminished the amount of carbon dioxide produced, making it more difficult to detect unless the carbon dioxide sensor was located very close to the wet grain. Relative humidity and temperature sensing gave good estimates of grain moisture for all conditions, but under some grain conditions, high carbon dioxide levels persisted for grain considered to be at safe moisture and temperature conditions. Combining relative humidity, temperature and carbon dioxide measurements gave reasonably accurate measurements of grain moisture content as well as overall storage conditions. ARS is the Unites States Department of Agriculture's scientific research agency. |
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| Custom machine rates guide Many farmers hire some farm machine work to be done or else perform custom work for others. What is a fair amount to charge or to pay for such work? Michigan State University has Extension Bulletin E-2131, Revised October 2002 available free of charge, which outlines labor, tractor, and machine rental rates based upon a survey from around the state of Michigan. Because there is no standardized market structure for custom machine services, determining a fair price can be difficult. Rates will vary across the state due to many factors, such as field size, weeds or stones in the field, non-farm traffic and transport, weather, distance to the field or elevator, timeliness of work, and even the yield. Some custom machine rate numbers for the following items might be helpful for farmers as they settle up accounts for tillage work. The following numbers are average rates, which means half of the survey numbers are lower and half are higher. All rates are per acre unless otherwise noted.
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| Web links to articles on corn harvesting The University of Minnesota Crop eNews published a couple resourceful articles recently. Below you will find brief summaries and links to the articles on the web. Avoid excessive harvest of corn residue to maintain soil productivity In most fields, corn residue remaining after grain harvest is incorporated into the soil with tillage or is left on the soil surface. Currently, corn residue is being harvested by some livestock producers, and there is interest in producing ethanol from corn residue in the near future (Perlack et al., 2005). However, soil productivity (synonymous with soil carbon) will be reduced if all corn residue in a field is harvested regularly and there is not another source of carbon being returned to the soil to replace the carbon removed with the residue. Read more at: http://www.extension.umn.edu/cropenews/2008/08MNCN28.html Energy costs for corn drying and cooling The purpose of this brief article is to provide enough information so that readers can estimate costs for drying and cooling corn. Grain needs to be dry to be stored through warm weather and it takes some energy to remove moisture from grain, but there are things that can be done to manage energy use. Read more at: http://www.extension.umn.edu/cropenews/2008/08MNCN27.html |
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| Employee dismissal Dismissal is the involuntary termination of an employee’s employment. Because emotions are often high, dismissals need to be handled with great care, or avoided. How can managers avoid dismissals? Careful selection, training, and management decisions serve to reduce the number of dismissals. In any case, a dismissal should only be considered after other options have been tried and did not lead to the desired results. Except in cases of gross misconduct, the dismissal should not come unexpected to the employee. Managers need to make sure that sufficient opportunities for changes were provided and a fair disciplinary process was followed. In addition, regular evaluation of an employee’s performance and a paper trail regarding performance appraisals and disciplinary actions is a must should a terminated employee challenge the dismissal in court. Michigan is an at-will employment state. What this means is that in the absence of a contract, the employee can resign at any time and for any reason and the employer can terminate for any reason or with no reason. Two exceptions apply in Michigan: the public-policy exception and the implied-contract exception. The public-policy exception prevents employees from being terminated for an action supported by the State’s constitution and statutes. For example, civil rights and equal employment opportunity legislation prohibit discharge based on an employee’s protected characteristics, including race, color, religion, sex, national origin, age, and disability status. Other examples are the reporting of dangerous workplace conditions, union activities, and the refusal to break the law on the employer’s request. The implied-contract exception is brought on by an employer’s oral or written assurances with respect to job security or disciplinary procedures. For example, an employee handbook describing procedures to be followed if disciplinary action becomes necessary or statements to the effect that no employee will be fired without just cause create an implied contract. Then the employer needs to follow the described procedures. Also, if a manager in charge of hiring, or the employee’s supervisor tells him or her that the employment will continue for as long as the work performed is adequate, an implied contract is created. If an employee’s dismissal does not comply with the law or does not comply with contractual agreements stated or implied in handbooks, application forms, or other company documents, it is considered a wrongful discharge. A wrongful discharge may be actionable in court. Even if a plaintiff does not prevail, management time and attorney costs are reasons to carefully review company policies before dismissal decisions, in particular when the dismissal is without cause. As a preventive measure employers need to review and regularly update their employment documents, if they want to ensure an at-will employment relationship with their employees. However, less job security may also result in less loyalty from the employees. Other important decisions in dismissal are how to conduct a termination interview and whether to offer severance pay. To read Dr. Bitsch’s complete newsletter go to her website at http://www.msu.edu/user/bitsch. Under “News” click on “Agricultural Labor Issues in Michigan” for a list of available newsletters. Please remember that these newsletters serve educational purposes only and do not constitute legal advice. |
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| Regional reports 1 -- Southeast Ned Birkey Weather Weather has finally given southeast Michigan some rain, from three to eight inches. Most of the rain this past weekend fell gently enough that there was not a lot of runoff. We were so dry that many tile lines are still not running. Crop report Alfalfa seeding will finally take hold. The third cutting was minimal, with potato leafhopper damage and likely Boron deficiency as well. There will probably not be enough time for regrowth for a fourth cutting this fall. I expect hay prices to be high again this winter. Corn plants have been drying up with some combines starting to roll. I have heard reports of grain moisture running from 23 to 29 percent. Test weight is light, 52 pounds in one case and ear diameter is small. Stalks are brittle and weak in many fields due to the excessive and prolonged dry weather in late July, throughout August and into September. Some lodging occurred over the weekend. Some harvest will begin this week as the fields dry out. Insect traps were pulled out a week ago as there was very little European corn borer, corn earworm, variant western corn rootworm and western bean cutworm activity. Soybean harvest started before last week’s rains. Initial yield reports are low due to the dry weather. Harvest will begin in earnest as fields dry out this week. I doubt that the STARS fungicide, insecticide and foliar fertilizer plots will produce a benefit this year as we were too dry for soybeans to do any mid- to late season growing. I suspect that Hurricane Ike sent viable soybean rust spores our way this past week. I will be monitoring the double crop soybeans for rust until we get a killing frost. Wheat planting will begin as soon as the soybeans are off the fields. It will be interesting to see if more soft white wheat gets planted this fall as Nabisco wants more white wheat. Farmers with on-farm grain storage would benefit the most as they could combine at slightly higher moisture next summer and keep the wheat in good condition. Miscellaneous We need good fall harvest weather to salvage the lower yielding crops. |
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| 4 -- Central Paul Gross Weather The region has been receiving more than adequate rains over the past weeks. The rains last week brought over four inches in some areas. This has left fields saturated in some areas and brought field work to a halt. Some farmers are getting back into the fields Wednesday to chop corn silage. We expect field work to continue with the warm dry weather the last few days. Crop report Harvest of corn silage is starting again as fields dry out. Some areas already have silage harvest wrapped up while in the northern part of the region harvest is just getting under way. The yields vary widely and depend mostly on how much rain was received over the summer. Harvest of high moisture will begin soon while grain harvest is several weeks away. Most farmers think yields will be all over the board depending on rainfall. Farmers are advised to scout fields for western bean cutworm. We have been finding this pest in nearly all parts of the region. Soybeans are beginning to turn rapidly and some harvest should begin later next week if field conditions allow. Most farmers are expecting average yields as the dry weather in August was just more than the crop could tolerate. Alfalfa harvest of third and fourth cutting is underway or just complete. Most are reporting very good yield and quality. This year seems like last in that the later cuttings are higher yielding than the earlier cuttings. While forage supplies are still short across the state, we are starting to see inventories build. Dry bean harvest has been halted by the rains over the past week. Some farmers are optimistic about yields where rains were adequate. Wheat planting will get underway when field conditions allow and soybeans are harvested. Most wheat acres follow soybeans in this area Sugar beets are doing very well with the rains. They are putting on the tons. Yields estimates and prospects look very good. |
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| Weather news Jeff Andresen Agricultural Meteorology Geography Tropical visitors What a difference a week makes. During the latter half of the 2008 growing season, the majority of Michigan and the eastern Midwest region experienced much drier than normal weather, with less than half of normal precipitation mid-July through early September. Enter the Atlantic hurricane season. Relatively weak upper air winds and warm sea surface temperatures across the subtropical Atlantic basin have led to a very active season thus far, with 10 named storms. While hurricanes, generically referred to as “tropical cyclones,” and their remnants typically move poleward from tropical and subtropical origins at some point in their lifetime, it is somewhat unusual for them to impact Michigan and the Great Lakes region as the storms must make landfall in an area potentially upwind of the region and then upper air winds have to be just right to advect or transport the remnants here before the system completely dissipates. After making landfall, the storms weaken as they lose the major source or their energy, water vapor from a warm ocean, and if they move poleward and persist long enough, they may transform into their mid- and upper latitude sibling, the extra-tropical cyclone, the type of low pressure area that brings us the majority of our precipitation year-round. This year, we have really beaten the odds, as three separate tropical-origin systems have impacted the state. The first was Hurricane Gustav, or more precisely, its remnants, which initially made landfall in Louisiana and moved through Michigan on September 3 and 4. This system brought over four inches of rain to western sections of the Lower Peninsula. Because the rain with this system fell in a steady, moderate intensity over a several hour period, in contrast with a heavy thunderstorm event in which the rain falls at sometimes torrential rates over short periods and runs off, the vast majority of the precipitation soaked into the soil profile. This past weekend (September 12-14), Michigan was >visited by two more tropical systems. The first was the remnants of Tropical Storm Lowell, which made landfall in northwestern Mexico last week. The remnant moisture from this system was caught up in strong southwesterly low-level winds and transported into the Midwest. An extratropical upper air disturbance and cool front at the surface moved into the region last Friday, providing strong lift for the residual moisture. The result was a widespread area of heavy rain from Illinois and Indiana into southern Lower Michigan overnight Friday into Saturday. More than six inches of rain fell in the Chicago area, setting a new all-time record for precipitation in a 24-hour period. Just a day later, Hurricane Ike made landfall in the Galveston, Texas area. The southwesterly winds that brought the remnants of Lowell into the Midwest were still in place across the region, and Ike=s remnants moved quickly north and eastward into the Great Lakes region by early Sunday morning, Galveston is about 1,200 miles away from Michigan and it moved here in approximately 30 hours, which is an average rate of about 40 mph, with another round of heavy rain. Relatively strong winds, 15-25 miles/hour with higher gusts, were still present with the system as it moved through southern Lower Michigan. The spatial pattern of rainfall during the last 30 days illustrates well the movement of the three tropical systems into the Great Lakes (see Figure 1). More than 10 inches of rain have fallen at some locations across the southwestern Lower Peninsula, leading to flooding and water-logged soils, and some new rainfall records. Normal rainfall for this period generally ranges from three to four inches. Unfortunately, the recent rainfall generally missed some northern sections of the state, and drought conditions continue there. Finally, it is interesting to note that the wettest month climatologically over most of Michigan tends to be a summer month (e.g. June). However, September also shows up as the wettest month at some locations. After this past weekend, we at the state climatologist=s office are very curious about the role of tropical moisture in our climate and how frequently it is a factor in Michigan (maybe more than we had suspected previously). A study is under way...
Looking ahead In contrast to the turbulent weather of the past week, high pressure across the Great Lakes region should lead to generally fair and dry conditions into the weekend and likely longer. This weather pattern should be very favorable for crop drydown, harvest, and fieldwork activities. Temperatures will remain at near normal levels during the next couple of days, with highs Thursday from the 60s north to the low and mid-70s south and lows generally from the mid-40s north to mid-50s south through the early weekend. A weak cool front is expected to move through the state late Friday into Saturday, but given little moisture ahead of the front, any rainfall with the system should be light and isolated, with most locations remaining dry. Temperatures will fall back a few degrees Sunday and Monday following the passage of the front, but warmer temperatures, highs back into the 70s to near 80°F in many locations, are likely again much of next week with the eventual formation of an upper air trough across western sections of North America and ridging across the east, which typically results in a warmer and drier than normal pattern in Michigan. NOAA medium range forecasts follow this trend as well, with National Weather Service 6 ‑ 10 day, covering September 23-27, and 8 ‑ 14 day, covering September 25-October 1, outlooks both calling for above normal mean temperatures statewide. Precipitation totals are generally forecast to range from below normal levels in eastern sections of the state to near normal levels in the northwest. Longer lead outlooks from NOAA's Climate Prediction Center (CPC) for the next few months in Michigan remain generally vague. The NOAA 30-day outlook for the month of September calls for cooler than normal mean temperatures across large areas of the Midwest and Great Plains regions. The outlook also calls for above normal precipitation totals across much of the southeast United States due to an active tropical storm season in the Northwest Atlantic Basin. For Michigan, the official outlook still places all of the state in the equal odds scenario of below, near, and above normal mean temperatures and precipitation totals. The NOAA outlook for September through November continues to call for increased odds of above normal temperatures state- and regionwide, but no forecast direction for precipitation (i.e. the equal odds scenario). |
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