Wednesday, March 8, 2017

Old Man Winter is Knocking & Snow Potential

It was inevitable. I've been basking in the early warmth of Spring just like many of you out there for weeks now. I've also been stressing that until we get entirely through the month of March, snow is NOT out of the question. With that being said it's going to be a wild weather ride for the next 7 days. We're becoming quite confident that snow will impact much of the area Saturday into Sunday. Mixing with rain for the onset, the switch-over to snow will take place by Saturday night. The GFS computer model (pictured below) seems to be the most reasonable guidance as of Wednesday night. It is a nice middle ground projection and other computer models are starting to show guidance closer to it's output. The greatest chance of accumulating snow will reside over the Ozarks of Missouri then we should see a swath of snow into the Purchase Area of Western Kentucky and down across NW Tennessee. 
Click to enlarge. Credit: WxBell
Snow is the least of our concerns though as this wintry blast will possibly bring a killing freeze. It's a halt on the early start to the growing season and damage for fruit farmers across the Mid-South . 
Also featured below is a look at 3 computer model projections as of Wednesday night. While the numbers may change slightly by the start of the weekend, the 1-3" range is a pretty good bet. Elevated landscape like the Ozarks could see a little more. Some areas may also see initial snowfall melt on contact. Since the ground soil temperature is already fairly mild (in the 50's) then any snow that does accumulate probably won't stick around very long. Because much of the snow will likely fall Saturday night there may be some initial roads with slick spots where untreated on Sunday morning. Additional updates will be posted here as we move closer to the weekend. 

Friday, March 3, 2017

Tri-State Tornado Double Take

Credit: Chris Conley, Spotter
 A well-forecast severe weather event unfolded Tuesday night starting in Southeast Missouri then blowing east into Southern Illinois, The Paducah National Weather Service along with local media gave people in Perryville, MO the early alarm that a large tornado was barreling their way. Storm spotter Chris Conley captured power flashes (right) from the violent tornado hitting power lines as the storm traveled from Perryville across the Mississippi River into Rockwood, IL after claiming one man's life on Interstate 55 and injuring 12 in Perryville.

Credit: John Humphress, Spotter
The supercell thunderstorm parent to this tornado was only getting started. Confirmation of a tornado and a trail of damage was reported in Rockwood, Ava, Elkville, Christopher, Buckner, Enfield and Crossfield, IL. Storm spotter John Humphress captured the wedge tornado (left) that struck Crossville where a man was killed trying to take shelter. Humphress recalled the strange, loud humming he heard in the trees as the tornado approached.  Assessment teams from the Paducah National Weather Service found  multiple tornado tracks from Missouri to Illinois and Indiana. The first tornado trekked 50.4 miles from NW Perryville, MO to near Christopher, IL. Damage was rated at a mid-range EF4 with max winds of 180 mph. The first tornado dissipated then another developed between Carmi and Crossville, IL and traveled 44.6 miles to near Oakland City, IN. Damage there was rated at EF-3.

Credit: Paducah National Weather Service
During those assessments it was discovered that one of the houses near Crossville (right) was not only damaged Tuesday night, but also sustained damage from the Tri-State tornado of 1925! Simply incredible.

The parent storm of these particular tornadoes that night took a hauntingly similar path as a very well-known tornado in the area's past. It's been identified as the worst tornado in the United States....The Great Tri-State Tornado 1925. "Worst" is used when defining for longest track, longest duration and deadliest. The story and finer details of this particular tornado have been researched for decades. In 2013 the most recent paper was published and is what I consider to be a "final" report concerning this horrific tornado. Written by some of the best meteorologists in the scientific community, years of collecting data town to town in the path, has in fact determined the validity of one complete and devastating track. Their researched damage path of the 1925 Tri-State is shown in the map below.
Map Credit: The 1925 Tri-State Damage Path and Associated Storm System Research Paper along with layered storm reports from the Paducah National Weather Service noted by Jennifer Rukavina

Since the Great Tri-State, there has never been a tornado that rivaled all of its characteristics. It is hard though to deny how eerie the realization had become on Tuesday night when we started connecting the green dots in the above map. A tornado outbreak was unfolding and in some ways much like that soupy March day back in 1925.
The weather pattern was slightly different and the time of day probably made the biggest difference between these two cases. Similarly these two storms traveled along a moisture boundary across Southern Illinois as an area of low pressure surged NE toward the Great Lakes. The Great Tri-State likely thrived better with the support of diurnal heating of the day. The February 28th storm was not diurnally based and developed during the dark hours of the evening.

Please ask permission to share photos featured by John Humphress or Chris Conley featured in this blog.