Severe weather hit the South hard in February of 2013, but since has been scarce. The large scale North American pattern is to blame; persistent troughing in the East with persistent ridging in the West. This pattern is probably the most effective at limiting severe weather for the United States. We expected this pattern to be persistent through most of the Spring of 2013 from our successful late February forecast, so as Juston and I hit the road to find dramatic weather our journey became a struggle.
We found ourselves chasing an early May snowstorm east of Kansas City, and minor Mississippi River flooding near Memphis. Big supercells and especially tornadoes were very rare. We’ve managed to document 3 tornadoes so far this Spring; 2 in Northeast Colorado and 1 in Southwest Oklahoma. Supercells were more common, but they were typically weak and relatively short lived, elevated, or outflow dominant. We managed to get large hail on a few occasions even losing our back window and windshield to 4+ inch diameter hail in South Texas. Strong CAPs, veered southwesterly low-level flow weakened dryline boundaries and mixed-out low-level moisture, poor deep-layer shear, and powerful cold fronts have dominated many possible severe weather setups, which are all expected from this type of large scale pattern.
The pattern appears to be changing, for how long is uncertain, but widespread severe weather events may by affecting the Plains and Eastern United States from Late May through Early June. Tornadoes and large long-track destructive supercells will probably become more common over the upcoming weeks. We’ll continue to document and report the severe weather as we have all Spring, but the intensity and amount of severe weather will most likely dramatically increase.
Below are a few photos we’ve taken so far this year:
Monday begins Tornado Week on The Weather Channel and new episodes of “Storm Riders” will air Tuesday April 30 8pm EDT/7pm CDT. Reruns of the new “Storm Riders” episodes will air Thursday May 2 8pm EDT/7pm CDT and Friday May 3 8pm EDT/7pm CDT.
Link for Tornado Week on The Weather Channel
“Storm Riders” is produced by NBC Peacock Productions and airs on The Weather Channel. The show features meteorologists and storm chasers, Simon Brewer and Juston Drake, as they criss cross North America in search of monster storms and extreme weather using their weather expertise. The only drama in this show comes from the intense and deadly weather events they experience and document with a passion unmatched on television. Brave NBC Peacock Producers and Shooters ride along with Simon and Juston showing the world what it’s like to be in the heart of the most intense weather on the planet.
The new episodes of “Storm Riders” are from the fourth season of the series shot during the Spring of 2012. The series began shooting on June 12, 2009 with most of the First Season shot by a lone Produce and Shooter, Erin McGarry, during the last 2 weeks of June. Season 2 was much more exciting covering the very active Spring of 2010. Season 3 was very intense covering many strong and deadly tornadoes from the violent Spring of 2011. Two hurricanes, Hurricanes Bill and Irene, as well as a devastating ice storm over West Oklahoma were covered during the “Storm Riders” series. Many notable storms and tornadoes did not make the cut during the four year production of the “Storm Riders” Series. Dr. Greg Forbes joined Simon and Juston for several days in June of 2010 highlighted by large destructive hail, a weak tornado in South Dakota, and a direct hit by a rain-wrapped tornado associated with a bookend vortex on the north end of a bow-line segment thunderstorm.
Notable Images from the New Fourth Season of “Storm Riders”
The March of 2013 weather pattern for the United States was dominated by persistent upper-level troughing in the East and ridging in the West. This pattern was conducive for veered low-level flow associated with troughs entering over the Great Plains and dry/cool to cold airmasses being forced into the eastern United States and Gulf of Mexico. The airmasses cooled and modified the, usually, moist low-level airmass over the Gulf. The modified airmasses over the Gulf became significantly drier and provided very little moisture for troughs entering over the Great Plains. Veered 850mb winds associated with each Great Plains trough in this pattern combined with the lack of deep unmodified Gulf moisture to create less than marginal severe weather setups. Troughs exiting the Great Plains were able to access deeper Gulf moisture producing most severe weather episodes in the Southeast.
During the month of April 2013 the pattern has changed slightly. A western trough has developed along with an eastern ridge. This is typically a classic severe weather pattern for the United States allowing for a steady flow of deep Gulf of Mexico moisture to become intertwined with powerful Spring troughs entering the Great Plains. But, there is a significant drought still affecting the Southwest United States pumping a strong inversion layer known as the CAP over the Plains. Also, each trough still has trouble with cool to cold dry airmasses plowing through the northern and western High Plains. The low-level wind field of each trough has also become quite veered due to persistent Great Lakes troughing, so each potential event has not produced widespread severe weather.
The pattern continues April 15-18 with potential severe weather events from the Great Plains to the Mississippi, Ohio, and Tennessee River Valleys:
Monday (April 15) setup appears to be focused over eastern Oklahoma, southern Missouri, and Arkansas near a stalled cold front boundary. The CAP appears to be very strong and significant upper-level lift may be too far away for surface-based storms to develop.
Tuesday (April 16) appears to have potential once again along a stalled cold front boundary, but this time near the Red River region of Oklahoma and Texas. Upper-level lift may be too far to the West and the CAP will be strong, so surface-based storm may not fire until well after dark.
Wednesday (April 17) has more substantial severe weather potential, but the combination of night and morning precipitation might drive the retreating warm front southward as an outflow enhanced cold front. The CAP might not be a significant problem on this day and might actually help keep convection isolated. There is both potential for a significant severe weather outbreak and a big precipitation mess on this day.
Thursday (April 18) appears to have the greatest potential for a significant widespread severe weather outbreak. A very powerful negatively-tilted trough appears to be progressing eastward over the Plains and affecting the Mississippi and Ohio River Valleys. A large region may be affected by a deep moist subtropical airmass under a highly sheered environment conducive for tornadic supercell thunderstorms from Lousiana to Indiana. A surging cold front in western Missouri and Arkansas will most likely cause a squall line of thunderstorms to develop, while more widespread isolated supercells might fire over the warm sector from northern Louisiana to Indiana and Illinois.
The pattern will change once again as this trough passes into the eastern United States.
Jim Bishop and I began Stormgasm.com with the intent to share our experiences with the world. The website has tranformed as we have evolved as meteorologists and storm chasers. We have expanded our adventures and experiences beyond the atmosphere to wilderness, volcanoes, earthquakes, and the cosmos. Earth Storm is now another avenue to help share our experiences and understanding of Nature’s most powerful and amazing forces.