The first week in July has started off as wet across much of the Central and Southern US. Widespread amounts of 1 – 3 inches have been common as show by the areas of green and yellow in the graphic below. However pockets of 5 to around 8 inches have occurred in Wisconsin, Missouri, Tennessee, Kentucky, Mississippi and Arkansas. These rains have further aggravated the areal and river flooding problems.
A cold front slowly pushing south across the Central and Southern Plains as well as the Ohio River Valley will be the focus for continued shower and thunderstorm development through much of the week. Average rainfall amounts will typically be 2 inches and less through Friday Morning. However for parts of Texas, Oklahoma and Missouri, rainfall amounts will be higher with 2 to 5 inches possible. Note a bright spot in the forecast, is rainfall is expected for parts of drought stricken Oregon and California.
While widespread totals are not expected to exceed 5 inches, some locations will experience localized heavy rainfall which may trigger flash flooding and lead to widespread areas of slow moving or standing water.
The atmosphere is very juicy across much of Texas, Oklahoma, and Missouri. Even parts of Illinois are experiencing the tropical like air mass. The measurement of atmospheric moisture from the soundings or balloons this morning from the NWS Norman, OK and Springfield, MO offices identified much above normal moisture levels. The graphic below shows the climatology of moisture levels for both Springfield and Norman. The green star highlights today’s measurements. Note the star is above the deep red line for both locations which depicts the maximum precipitable water daily moving average line. So the measurement of 2.08 inches at Norman and 2.25 inches at Springfield are approaching the all-time records. While not shown in the graphic below, the measurement for Lincoln, IL was 1.97 inches and is just below their maximum moving average for the day.
These sounding measurements reinforce the potential for localized intense rainfall. Already this morning, parts of southwestern Missouri were seeing hourly rainfall rates of 1.5 to 3 inches per hour.
Given the recent heavy rains across much of this region, soils are fairly saturated. Hence, they do not have much capacity to absorb the additional rainfall, especially when the rain is intense. The graphic below highlights that for areas in red, it will only take 1.25 to ~ 2 inches of rain in an hour before flooding is experienced. For the areas in pink and purple, it will only take 0.5 to 1.25 inches of rain before flooding maybe come a problem.
So what are the implications of this continued wet pattern? Not surprising the river flood risk continues, especially in the mid-section of the US and the southern Plain States. The graphics below highlights the river forecast locations that are at an increased risk for seeing continued and or more significant flooding than what is occurring. Industries with interests along these river systems should remain aware for rising water levels.
In addition to river flooding, areal flooding and problems related to standing water, especially in fields will continue to be an impact.
Of particular concern, are the implications the continued moisture will be to agriculture and hay industry. With brief dry period’s in-between each round of rain, many farmers have had little time to cut and bale their hay. While they may be able to cut the hay, they are not having enough drying time to bale it. Thus they are having to hold off cutting or sometimes taking their chances that showers will miss them and leaving it in the field to dry.
According to a recent article by Daniel Lima with Ohio State University in Farm Journal, even in Ohio, “baling hay has been a tough thing for most farmers in the state.”
The main challenge is the critical “20% moisture maximum” for baling the hay. He further states “Hay baled at 20% moisture or higher has a high probability of developing mold, which will decrease the quality of hay by decreasing both protein and total nonstructural carbohydrates (TNC) AKA energy! The mold will also make the hay less palatable to livestock and could potentially be toxic, especially for horses. Even hay baled between 15%-20% moisture will experience what is known as “sweating”. Sweating, in regard to hay bales, refers to microbial respiration, which will create heat and result in dry matter (DM) loss.”
Another concern with the continued wet pattern is ranchers are moving their hay bales into their barns. According to an article by Beef Today, this strategy might actually place your barn structure at an increased risk of a fire. Keith Johnson, a Purdue Extension forage specialists indicates that “If hay is not given enough time to dry or is stored prematurely, heat-tolerant microorganisms can develop in the bales, raising the temperature.” Once hay reaches a temperature of 200 degrees F, the spontaneous combustion or the hay igniting is likely.
Johnson provided two recommendations “ farmers could speed up the drying by laying the cut forage in a wide swath with a mower-conditioner. Hay cut in a wide swath is more exposed to sunlight and dries faster. The conditioner crimps the stems of newly cut wheat and allows moisture to evaporate faster.” Another Alternative “let the cut forage wilt to 50 percent moisture content and allow it to ferment to silage. This is done using an individual bale wrapper or an inline tuber that exudes air by wrapping the bales in white plastic.“
So until the rain starts to let up, farmers and ranchers will continue to have problems cutting, supplying and storing their hay bales.
The team at WxIntegrations will continue to provide you the relevant information and resources to help you better understand and prepare for the forecast weather through incorporating weather impacts into your planning and response.
For those in the Heartland and central and southern Plains States, we urge individuals to remain aware of the weather and river forecasts and potential compounding impacts due to additional rainfall expected this week.