The severe thunderstorm watch for the final and least destructive round of stormsThe SPC had issued this high risk on the day three outlook for the first time in history. Once July 29 finally rolled around, the SPC had maxed out all risks. There was a 60% significant tornado risk, a 60% significant wind risk and a 60% significant hail risk. In addition there was also a high risk for excessive rainfall over the high risk area.
Despite an active start to the 2020 tornado season in January and February, the number of tornadoes in March reverted to the average despite deadly tornadoes in Nashville, Tennessee, March 2-3. There have been 245 preliminary filtered reports of tornadoes in the United States in 2020, of which 209 have been confirmed. 34 tornado-related deaths have been confirmed worldwide, all in the United States. Experts warn that tornadoes can produce scary high winds and damage and to be sure to be careful.
All the ingredients were in place for a truly extreme day in severe weather. After 12:00 P.M. The watches began to be sent out. The most interesting watch was a PDS tornado watch for central Minnesota, Northeast Iowa and wester Wisconsin. All watch probabilities were maxed out at 95% (Only the third time on record that has happened!).
For risks the watch said some truly scary statements.People in and close to the watch area should prepare for the following,Widespread violent, long tracked and deadly tornadoes.Widespread extreme hail exceeding 4 inches.Widespread Extreme wind gusts over 90 MPH and isolated gusts over 110 MPH.Also be aware of deadly lightning and extreme rainfall and from multiple rounds of thunderstorms.This was the second watch to be issued for this area. The first one was for central and eastern Minnesota into west central Wisconsin. That was associated with extreme squall line. Day one had four distinct rounds of severe weather.Wind Event of Day One (Round 1 of Severe Weather)The first round of severe weather was a squall line that began around 2:45 A.M in eastern South and North Dakota. This line extended from west of Fargo North Dakota to Sioux Falls South Dakota.
Multiple bowing segments made up the line with the most extreme winds located in these areas. The line raced east at an average speed of 65 MPH. By 7:30 A.M, the line had reached central Minnesota and a tornado watch was issued for western Wisconsin and eastern Minnesota including the Twin Cities Metro. Shortly after, a mesoscale discussion was issued for eastern Minnesota. It mentioned a particularly intense bowing segment that was headed straight for the Twin Cities. It mentioned the possibility of sustained winds reaching 100 MPH. The Line plowed into the Twin Cities and Minneapolis Airport measured a wind gust of 135 MPH.
The line began to rapidly weaken after moving into central Wisconsin. The now significantly weaker line only had a few severe segments as it entered Michigan producing winds of 60 MPH at grand rapids causing scattered tree damage and power outages. Gallery from Squall Line. Radar Image of the tornadoAs the squall line began to bow out significantly, a strong tornado touched down 5 miles west of Arlington and did EF2 damage to several homes and farms.
This tornado quickly became violent and became an EF3 as it tore through the center of Arlington collapsing exterior walls and throwing cars. Power was out to the whole town as well. At peak intensity this tornado had estimated winds of 155 MPH. As with most QLCS tornadoes, this tornado did not last long and dissipated after doing high end EF1 damage to a farmstead 4 miles west of Arlington.Lester Prairie MN EF4. EF4 Damage in Lester PrairieThe most powerful tornado associated with the squall line was a destructive EF4 tornado that tore through Lester Prairie.
Tornadoes of this magnitude are extremely rare. The tornado first touched down several miles west of Lester Prairie and did EF3 damage straight away to several farmsteads. Many outbuildings were completely destroyed or levels and houses had their roofs removed and severe exterior wall damage. The tornado did a brief instance of high end EF3 damage 2 miles west of Lester Prairie where winds were estimated at 165 MPH. By the time it reached Lester Prairie it had peaked in strength. The tornado tracked directly through the town at EF4 intensity with winds of 180 MPH.
Over 50 buildings were levels or had a few damaged interior walls remaining, cars smashed and power lines and tress snapped and tossed. A small satellite tornado did EF1 damage to about 17 houses causing parts of the roof to be removed and siding damaged. The tornado had weakened back into EF3 status about 2 miles east of Lester Prairie and quickly weakened doing low end EF3 to EF2 damage to a few farms before dissipating.White Hall Michigan EF2. EF2 damage in White hallAs the squall line was overall on a weakening trend it produced one last strong tornado. This tornado touched down as a high end EF1 a few miles west of White Hall.
Some strengthening occurred and the tornado became a mid range EF2 with winds of 125 MPH as it entered western White Hall. The tornado snapped trees and power lines, flipped cars and destroyed exterior walls and roofs on buildings. The tornado weakened to EF1 in downtown White Hall but still did significant damage.
On the east side of White Hall, low end EF1 to EF0 damage was observed before the tornado dissipated.Main Supercells (Round 2 of Severe Weather)The worst round of severe weather would come in the second round. Training supercell thunderstorms developed across the high risk area producing a record amount of violent tornadoes. Eastern Minnesota and Western Wisocnsion were devastated by this round of severe weather with the Twin Cities experiencing multiple violent tornadoes.Extreme Hail (Round Three of Severe Weather)The third round was also extremly violent. More supercells with intense updrafts formed once again over the high risk area and quickly dropped incredablew sizes of hail with a storm tracking through downtown Minniapolis prodcing damaging winds and record setting volleyball sized hail (around 10 inches). Other reports of 4 inch or bigger hail occured aroudn Wisconsin and Minnesota as well.Minniapolis and St. Paul Record Hailstorm. General Severe Storms (Round 4 of Severe Weather)A few more storms formed around the Midwest in this round and produced some weaker severe thunderstornms.
A few more tornadoes touched down but generally they were weak. The strongest tornado with this round caused destruciton in southern Mankato Minnesota and was rated a high end EF2.Day 2 (July 30, 2020). The Day One Hail Risk for July 30, 2020Day 2 offered another batch of extreme weather. Two separate areas were being watched for possible significant weather. The hardly hit Twin Cities region was placed under a moderate risk for both tornadoes, wind and hail. A few more violent tornadoes touched down with destructive wind and large hail also occurring.
The main event would bbe the high risk area. Lot's of extremely strong storms occurred bringing lot's more violent tornado, Extreme wind and massive hail. A smaller severe event occurred in the northwest United States around the Seattle area.Day 3 (July 31, 2020). The Day One Hail Risk for July 31, 2020Another high risk was in place for day 3 signaling another eventful weather day. Two rounds of severe weather occured this day. Round one moved through the Florida peninsula causing widespread destructive winds and tornadoes with scattered hail. The second round was the main event with multiple intense supercells tracking mainly in the moderate and high risks areas.Round One of Severe Weather (Florida Squall)Similar to day one, the first round of severe weather was another powerful squall line with several bowing segments packing winds over 80 MPH.
The worst damage was in Orlando where winds gusted over 100 MPH and baseball sized hail fell. Several tornadoes (a few strong and one violent) also caused additional significant damage.