From possible winter to severe storms to end the week(3/3/23)

[nWo]

Last week the modeling guidance was showing a possible winter system dumping snow on Kentucky. There has been a big shift in the data.  It appears that there could a potential severe weather outbreak for Louisiana, Mississippi, Arkansas, and portions of Tennessee. At the moment. Kentucky is not in the picture but, if there is a northerly shift of the track of this system Kentucky could be added.  

This system will form  around California and move across the country. As it moves eastward it will turn over to a negative tilted trough. Negative tilted troughs usually begin as positive tiled troughs. As the short-wave energy races east though the longwave it distorts its shape from positive to neutral (north-south) orientation to a negative (northwest to southeast) orientation. These types of troughs produce the most severe weather. It becomes quite strong and could produce a severe weather outbreak.

 

 

If the Low pressure moves on the now indicated track it will past just the northwest of Kentucky. It the track shifts more to the north then Kentucky could come into play. As this system moves in a northeasterly direction a warm front will move north across the Kentucky during the day on Friday. Temperatures could range from the mid to upper 60s to the low 70s. As this warm Gulf air mass moves into Kentucky the dew points could rise to the low to mid 60s. There are three things to look for when predicting severe weather. Moisture, rising unstable air, and a lifting mechanism. At this point, the model guidance is showing all three. The following  maps will show this.

Temperature

 

Dew Point

 

500 mb Height, Vertical Velocity(lift in the atmosphere)

 

The Low Pressure system is the lifting mechanism

 

This is the simulated radar late Thursday night to Friday evening.

 

Now let me say everything could change as for timing, track and strength of this possible system. I do know that just about everyone is watching this. I as you may well know I've been keeping an eye on this since late last week. The Storm Prediction Center has been issuing Convective Outlooks since the weekend. I will post updates as we get closer. 

[nWo]

Wednesday morning update:

 

A negatively tilted upper-level trough and an area of low pressure are forecast to move quickly from the Ozark Plateau toward the lower Great Lakes on Friday. A cold front will move across much of the Southeast and TN/OH Valleys. Conditions will create an environment from the Southeast into the Ohio Valley, resulting in a broad area of severe-thunderstorm potential. The Storm Prediction Center has portions of Kentucky south of I-64 and east of I-65 in a level 2 Slight Risk Area. North of I-64 and west of I-65 to about the Land between the Lakes area is under a level 1 Marginal Risk Area. 

Please check back for updates.

 

[nWo]

 

Thursday morning update:

 

The threat for possible severe weather on Friday has increased. The Storm Prediction Center has expanded the level 2 Slight Risk Area to cover a majority of Kentucky. 

As a surface low moves northeastward, a broken line of showers/storms is expected to progress toward the Ohio Valley. With intense wind fields in place, the primary uncertainty regarding the  severe-wind and tornado threat is available instability near the low and southward across the warm sector. If even  modest destabilization and other severe perimeters  occur, a threat for severe/damaging gusts and perhaps a few tornadoes could materialize, with the greatest relative threat currently expected across some portion of KY/TN, where the most  favorable overlap of instability and continuous precipitation  is expected.
Uncertainty still remains but higher wind and/or tornado probabilities may eventually be needed depending model guidance. 

I may post another update in a coupe of hours. 

 

 

[nWo]

I wouldn't be  surprised if the threat level is elevated to a level three Moderate Risk for sections of Kentucky Friday. The 06 NAM 3km run shows the possibility of a tornado threat. This does not mean that a tornado will form just the possibility exist.  At this point ,the main threat period seems to be from 11 am to 5 pm EST as the cold front crosses Kentucky from west to east. Latest soundings indicate that any possible tornado that forms in a 25 mile radius of any given point could reach EF-2 status.