Bout of recent cold weather may be foreshadowing for spring and summer
April 17, 2012
by Drew Lerner
KANSAS CITY — A short-term bout of cold weather that impacted the eastern U.S. last week producing frost and freeze conditions from the Upper Midwest and northern Plains south to northern Mississippi, northern Alabama, northern Georgia and South Carolina may be foreshadowing weather for spring and summer.
The latest trend modeling of the atmosphere for the coming few weeks has suggested periodic bouts of cold air will sink southward across the eastern Canadian Prairies Provinces into the eastern Midwest. The pattern should reduce fear of returning hot, dry, weather that some meteorologists have been touting while raising concern over the prospects of additional frost in areas that were planted with corn earlier than usual.
Last week’s cold already has resulted in some minor damage to wheat and corn throughout the Midwest and into a part of the interior southeastern states. Production potentials were not seriously altered this time around because temperatures were just not quite cold enough and crops not quite advanced enough to cause permanent harm to production. Additional bouts of cold are slated into May and even though the atmosphere will be gradually warming during the period another frost threat cannot be ruled out.
World Weather, Inc.’s Trend Model suggests that the jet stream pattern in North America will be split over the next several weeks. One branch of the jet stream will bring storm systems into the southwestern Plains before shifting them to the Great Lakes region while the second branch of the jet stream brings frequent cool fronts from northwest to southeast across Canada and into a part of the Midwest. The pattern will be ideal for helping to provide a healing environment for those wheat and corn plants injured in last week’s frost and freeze event. The pattern also will be good for generating periodic precipitation, especially from the central and southwestern Great Plains into the heart of the Midwest.
However, the predicted pattern will not bode well for ending dryness in the northwestern Plains spring wheat region. The area from eastern Montana through South Dakota into a part of Nebraska has been quite dry in the past 30 days and the region needs significant moisture. The coming weather will bring a few opportunities for light rain, but no general soaking to restore long-term soil moisture.
Another group of unhappy farmers in coming weeks may be in the southeastern United States where below-average precipitation will prevail as well. Some areas in the southeastern states have seen well below average precipitation for months and the only thing separating the region from drought is the timeliness of precipitation that has fallen. Any disruption to the pattern could bring significant crop stress within a short period of time.
U.S. hard red wheat areas will not be bothered by the coming cooler weather in the eastern half of the nation. Most of the small grain crop in the central and southern Plains will see seasonable temperatures, on average, with no serious bout of damaging cold anticipated. Sufficient moisture will be around to help maintain a very fine summer crop development potential.
No chronic or persistent cold is expected in the eastern U.S. over the next few weeks. A good mix of warmer and cooler periods will evolve supporting both crop development potentials and planting progress.
The Pacific Northwest will be the one region in the nation where temperatures may see a little more warmth periodically. Temperatures in May will trend a little above average. Rainfall will be below normal in a part of Washington state while Idaho is a little wetter biased.
Growing degree days across the Midwest likely will be just slightly below average by the end of May, especially from the Great Lakes region and upper Mississippi River Valley into the Ohio River Valley. Growing degree days elsewhere will be closer to average.