Let’s start with today. The SPC Day 1 Outlook below shows parts of southwestern Missouri, southeastern Kansas, most of Oklahoma, and parts of northern Texas in the slight risk with the main threats being damaging hail with some severe criteria wind gusts as well.

Additionally, the SPC has once again warned about the risk of tornadoes for today, as shown below. The highest risk carries with it a 10% chance of a tornado within 25 miles of a point as well as a 10% or greater probability of an EF2 or greater intensity tornado within 25 miles of a point.
Now this seems pretty significant but let’s put it into perspective. The SPC has issued threats like this many times before, including yesterday when only one tornado was reported. That being said though, yesterday’s storms were hampered by cloud cover limiting solar heating during the day which made it difficult for rising air to be able to break the cap. Today, this cloud cover does not exist, or is at least not as widespread. Taking a look at the latest surface observations, temperatures appear to be warming up nicely as of late this morning and dew points are high as well, with readings in the low to mid 60s.
Based on the heating that has already occurred today, and is forecasted to continue throughout the day, and the lack of cloud cover this morning that allowed this to happen, I would expect that storms will actually break out this afternoon. In fact, the SPC has just issued the first tornado watch of the day which will be in effect until 9PM CDT due to the initiation of some of these storms already this afternoon.
Additionally, 0 to 3 km storm relative helicity and surface to 500 mb shear values from the NAM model, shown below, appear to be very favorable for just after sunset this evening. It appears these values will be marginal throughout the day but really line up early tonight and actually continue through the overnight as the 850 mb low-level jet continues to strengthen.
The bad part about this, is that most of the tornadoes that form will be at night tonight making them even more dangerous due to people not being able to see them or people just not getting the warnings because they are asleep. This is a weekend though, that residents of the Plains will need to remain alert because tonight is just the beginning to a long weekend of tornado threats.
Saturday is when things will really get serious. Below is the Day 2 Outlook from the SPC which depicts a high risk now for areas in northern central Oklahoma, southern central Kansas, parts of eastern Nebraska, and parts of western Iowa. This is only the second time the SPC has issued a high risk for a Day 2 product with the other time being an issuance for an April 7, 2006 event which produced over 70 confirmed tornadoes, though a few of these occurred the day before and after. Overall, April 7th was responsible for 91 tornado reports.
The probabilistic Day 2 Outlook, shown below, shows just how high of a risk some areas of the Plains will be dealing with on Saturday and Saturday night. The high risk areas from above are looking at a predicted 60% chance of severe weather within 25 miles of a point with another 10% or greater probability of significant severe weather within 25 miles of a point. Outside of this high risk threat, there is a very large area which is still in a slight or moderate risk for severe storms, with the moderate risk area being hatched for the 10% or greater probability of significant severe weather within 25 miles of a point.
While some storms may form during the afternoon, it appears the bulk of the activity will occur after dark. This will yet again make this outbreak more dangerous to life. The models are not picking up on a tremendous amount of precipitation from this event but given the forcing associated with the movement of the dry line and cold front across the Plains, this should be enough to lead to uplift capable of producing thunderstorms. It should also be noted that weather models tend to have a more difficult time picking up on mesoscale processes such as thunderstorms and this could also be a reason why the models are failing to produce many storms Saturday afternoon and evening. Once these storms form though, the physical parameters of the atmosphere will once again be very favorable. Below are the NAM model output for 0 to 3 km storm relative helicity and surface to 500 mb shear for Saturday night around midnight.
If storms are occurring during this time, which despite what the models are predicting they should be occurring, we could be looking at a major severe weather outbreak including multiple tornadoes. The low-level jet will be very strong across the threat area and this will definitely help aid in keeping the severe weather going throughout the night. This event is one that should not be taken lightly and the resident of the Plains should be keeping a close eye on it.
After Saturday night, which should be the worst of this event, the system will continue to push eastward. The SPC Day 3 Outlook is shown below depicting a slight risk for an area in and around Wisconsin as well as an area from southern Missouri south southwestward toward eastern Texas. This later risk area appears to have the best threat of severe storms on Sunday.
The threat may be more for line segments across Sunday and into Sunday night however. Shear and helicity values will not be very strong on Sunday but will strengthen again on Sunday night though due to the nature of the storms, tornadoes should not be as large of a threat. If supercells could form out in front of the main line of storms on Sunday night however, then tornadoes may become more of an issue but at this time it is hard to tell if the atmosphere will be unstable enough to produce these. The storm system will continue to push east Monday likely posing more areas at risk for severe weather to the east of Sunday’s threat area.
This could be a very large severe weather outbreak and with the bulk of the activity occurring after nightfall, it is of the utmost importance to remain aware of what is going on. Severe Studios storm chasers will be chasing all day today as well as Saturday and into Sunday so be sure to keep an eye on them on the ZoomRadar map if you are in an area that is safe to do so.
Be safe everyone!