We might as well start posting news articles from our local papers. It is about a relative!
Wednesday, August 04, 2004
Summer 2004 cooler, drier than averag
Minnesota's wheat harvest is now in full swing and the crop looks very good in most areas.
July became the third consecutive month with temperatures below average. The monthís high temperature averaged 82 degrees, 71 hundredths below the monthly average of 82.71 degrees. The low averaged 60.13 degrees, 1.16 degrees below the average of 61.29.
July saw two days, July 24 and 25, on which record cold temperatures were set.
July 25ís record low of 52 degrees set in 1958 was shattered when the temperature in Benson fell to 46 degrees early that day. The record low of 52 for July 24, set in 1998, was also broken when the temperature hit 50 degrees.
While July saw a high of 97 degrees July 21, it also saw one of the coldest July highs when on July 6 the high only reached 61 degrees. In all, July saw six days on which the high reached 90 or above.
Those persistently below-average temperatures during the past three months have slowed crop development in the state.
The highest average temperature of the year in Benson is 83 degrees. That average high starts July 10 and doesnít end until Aug. 3 - 24 consecutive days. August 4, the daily high average drops to 82 degrees and by the end of the month it will have dropped to 77 degrees.
The highest average low temperature the area sees each year is 62 degrees which arrives July 18 and ends Aug. 2. Through the month, the average low temperature will drop steadily, hitting 55 degrees Aug. 31.
In addition to remaining cooler than average, the summer of 2004 is staying on the dry side.
July saw 3.39 inches of rain compared to an average of 3.81 inches - 42 hundredths below the average. June fell 67 hundredths below the average of 4.21 inches.
For the year, the area is about half an inch below the average precipitation of 16.74 inches.
Statewide topsoil moisture supplies as of July 30 were rated 3 percent very short, 16 percent short, 76 percent adequate, and 5 percent surplus. Western Minnesota, including parts of Swift County, are now in the area indicated as being short of topsoil moisture.
Though rains have been below average this summer, they have come at the right times to keep area crops moving along.
Still, fields with irrigation systems have been watering regularly through the weeks between the sporadic rainfalls.
The spring wheat harvest began last week, with 1 percent harvested, according to the Minnesota Agricultural Statistics Service. But that percentage will increase rapidly in the next week as more and more farmers hit the fields with their combines. Farmers in the central part of the state report that small grains look excellent and they are expecting good yields.
Many corn producers are hoping for a late frost this year since crop progress is behind normal, due to lack of growing degree days.
The average date of the first frost in Benson is still a long way away - Sept. 30. The first killing frost, a temperature several degrees below 32 degrees, usually doesnít hit until around Oct. 10.
Warm and humid
The second half of July did see some warm, sticky days with dewpoints climbing into the very tropical lower 70s.
That sticky weather continued into early August with dewpoints of 70 to 72 degrees through the first three days of the month while high temperatures reached 84 degrees each of the days.
Temperatures in the low 80s with dewpoints of around 70 degrees can be hazardous to a personís health. When temperatures reach into the 90s, dewpoints in the 60s can cause health problems.
On average, about 175 Americans die each year due to the taxing demands of heat combined with high dewpoints. The human body dissipates heat by varying the rate and depth of blood circulation, by losing water through the skin and sweat glands, and as a last resort, by panting, when blood is heated above 98.6, according to the National Weather Service. Sweating cools the body through evaporation. However, high dewpoints slows evaporation, robbing the body of its ability to cool itself. This can lead to heath-related illnesses and even death.
The heat index which weather forecasts refer to is the temperature the body feels when heat and humidity are combined. Exposure to direct sunlight can increase the heat index by up to 15 degrees, a fact which many of those who work outside have to deal with.
Fortunately, dew points of 74 degrees or higher occur less than 1 percent of the time during the typical Minnesota summer, Mark Seeley, a climatologist with the University of Minnesota, reports.
Seeley has also reported that it appears Minnesota summers are becoming more humid.
Seeley has been analyzing climatic data gathered from around the state. His conclusion: the frequency of high "dew points" - the measure of humidity - has increased during the past half-century.
Unfortunately, it's not just the humidity - it's the duration as well. The number of hours at "tropical" humidity levels has been steadily growing, too.
Dew point is defined as the temperature at which water vapor will condense as dew onto a surface. A higher dew point means that more water vapor is suspended in the air. Dew points in the 70s, typical of tropical weather, are not uncommon in Minnesota. But now, weather services are recording more hours with dew points higher than 75.
Though the entire state is seeing an increase in dew points, the southern half of Minnesota in particular has experienced record-high dew points in the past five or six years. Dew points above 80 are exceedingly rare. But in the last several years, multiple readings as high as 84 degrees have been recorded.
The reason for the increased humidity has been baffling scientists.
Seeley believes that one possibility is irrigated farmland west of Minnesota. He says Nebraska, for instance, has irrigated about 7 million acres, and all that moist farmland can affect the climate like a gigantic lake.
There's another possibility as well.
"I can't dismiss the idea that global warming somehow is playing into this," Seeley said.
According to NASA, Northern Hemisphere oceans have warmed in the past decade. Evaporation from the warmer ocean water may be pumping enormous amounts of vapor into the air.
If it continues, the trend could have some adverse effects.
Humidity helps bacteria and fungi that attack crops. Head scab, a fungus infection of small grains, already has caused billions of dollars' worth of losses in the Red River Valley. Jim Groth, a professor of plant pathology at the University of Minnesota, said there is no question that the worst years for head scab are the wet years.
But "potato blight is one to really worry about," Groth added. This fungus sets up shop on potato leaves as white patches and causes them to rot. It's the very same "bug" that caused the great Irish potato famine of the late 19th century, he said, and it's now a problem in northern Minnesota and on the East Coast.
Humans might become more sickly, too. Most doctors agree that high humidity promotes such respiratory-tract illnesses as bronchitis, sinusitis, colds and sore throats. Moisture problems in homes translate into allergy problems because household molds and dust mites thrive in humidity.
Corn silking was 79 percent, compared to 95 percent last year and 92 percent for the five-year average, the ag stats service reported.
Soybeans were 81 percent blooming, compared to 93 percent last year and 91 percent for the five-year average. Twenty-seven percent are setting pods, behind the five-year average of 39 percent.
Corn condition rating of good to excellent was 68 percent compared to 67 percent last week. Soybeans were rated 58 percent in good to excellent condition, compared to 55 percent last week.
Spring wheat turning ripe was at 58 percent, behind the five-year average of 80 percent. Spring wheat was 1 percent harvested, compared to 8 percent for the five-year average.
Barley turning ripe was at 60 percent compared to 93 percent last year and 84 percent for the five-year average. Barley was 4 percent harvested, compared to 13 percent for the five-year average. Oats were 81 percent turning ripe which is behind the five-year average of 92 percent. Oats were 16 percent harvested, compared to the five-year average of 28 percent.