Intense Storms Tonight (Oklahoma, Kansas, Missouri)

Severe thunderstorms are possible this afternoon and evening across eastern Kansas, western Missouri, and northern and central Oklahoma as a potent shortwave moves into the Southern Plains this evening. Currently, deep moisture is advancing northward across Texas and recent guidance suggests this moisture should move into the I-35 corridor and eastward in Oklahoma later today. This moisture will set the stage for thunderstorm initiation after 4:00PM for parts of Kansas with slower thunderstorm initiation in Oklahoma (probably around 6:00PM or later) due to a strong CAP.

The CAP between 6:00PM-9:00PM should weaken sufficiently to allow for a couple intense isolated storms to develop in the vicinity of a triple-point near the OKC Metro. These storms during this time frame would likely be severe due to the aforementioned moisture, high CAPE, and the low-level jet strengthening towards and after dusk. All modes of severe weather are possible, which includes tornadoes, large hail, and damaging winds. The Storm Prediction center has an enhanced risk of severe thunderstorms over northeastern Oklahoma and southeastern Kansas. A slight risk area surrounds the enhanced risk.

SPC Thunderstorm Outlook

It appears, initially, most of the storms will remain along and north of I-40 and along and east of I-35; however, it is possible for an isolated storm or two to develop south of I-40–towards the Norman, Oklahoma vicinity. Overnight, a line of storms will evolve and advance southeastward into Arkansas and much of southeastern Oklahoma (Texoma). The main threat overnight will be gusty winds and hail.

Severe Weather from the Plains to the Great Lakes

The severe weather season has gotten off to an active start this year.  After a couple of quiet days, we once again have a risk for some severe storms from Oklahoma up into the Mid Missouri Valley and Upper Mississippi Valley.  Large hail and damaging winds will be the primary threats with very large and damaging hail possible from southern Kansas to Southwestern Oklahoma.  A tornado or 2 can also not be ruled out.  These storms should initiate later this afternoon into this evening and will be widely spaced.  Clusters of development should form in places but see several dozen miles in distance to the next cluster of storms.

Severe Risk

severe

Hail Risk

The biggest risk today is hail, with the largest risk over the Plains.  A strong cap on storms there will make any updrafts that do occur very strong.

Upper Mississippi Valley and Missouri Valley

Widely Scattered Storms will occur late this afternoon on both sides of the warm front that extends from Eastern Nebraska to Southern Wisconsin.  Thunderstorms should also form as the cold front moves into the region down to the Missouri Valley.  Conditions are marginal for supercell development but weak flow will allow those storms to quickly form squall lines of storm clusters.

 

Central and Southern Plains

Any risk further south is much more conditional and local than the river valleys.  The dryline is weak this morning and though it will sharpen, the strong cap will provide plenty of inhibition to storm formation.   Any storm that does form will have a strong updraft capable of producing very large and damaging hail.  Given the isolated nature expected of these storms, the significant risk for hail area covers this region.

For Nebraska and Southern areas of south Dakota, storms will not be prolific rain producers.  While rain could fall heavily in storms, moisture is in very short supply for this region.  The cold front could still help support a few clusters of storms though and large hail is the primary risk.

 

Rob

Severe Weather to strike the Southeast

An outbreak of severe thunderstorms is likely Wednesday across much of the Southeast, continuing northward along and west of the Appalachians into the Tennessee and Ohio Valleys.  This will include supercell development with a risk for tornadoes, some of which will be strong and long-lived, particularly across the Southeast. Large to very large hail and damaging straight-line winds also appear likely.

severe

MODERATE 103,173 14,567,637 Atlanta, GA…Birmingham, AL…Montgomery, AL…Columbus, GA…Huntsville, AL…
ENHANCED 122,034 17,242,602 Indianapolis, IN…Nashville, TN…Cincinnati, OH…Lexington-Fayette, KY…Louisville, KY…
SLIGHT 149,867 22,769,267 Jacksonville, FL…Columbus, OH…Charlotte, NC…Virginia Beach, VA…Raleigh, NC…
MARGINAL 118,145 18,253,000 Tampa, FL…St. Louis, MO…St. Petersburg, FL…Fort Wayne, IN…Orlando, FL…

Thunderstorms are spreading across portions of the Florida panhandle, Southeast Alabama and Southwest Georgia early this morning.  These storms will spread northeast and continue to grow throughout the day.   Hail looks to be the early risk here.

SIG SEVERE 84,950 13,240,373 Atlanta, GA…Birmingham, AL…Montgomery, AL…Columbus, GA…Huntsville, AL…
45 % 85,208 13,300,208 Atlanta, GA…Birmingham, AL…Montgomery, AL…Columbus, GA…Huntsville, AL…
30 % 139,977 18,619,298 Indianapolis, IN…Nashville, TN…Cincinnati, OH…Lexington-Fayette, KY…Louisville, KY…
15 % 150,323 22,775,864 Jacksonville, FL…Columbus, OH…Charlotte, NC…Virginia Beach, VA…Raleigh, NC…
5 % 118,900 18,265,296 Tampa, FL…St. Louis, MO…St. Petersburg, FL…Fort Wayne, IN…Orlando, FL…

This situation looks to be very dangerous, and while a high risk has not yet been issued, it is still possible for one to be issued later in the day.   Many schools have already closed due to the threat and Alabama has pre-emptively declared a state of emergency.  Please take whatever time you have available to make preparations this morning.  This is the current risk for tornadoes.

SIG SEVERE 68,331 7,831,596 Columbus, GA…Huntsville, AL…Chattanooga, TN…Columbia, SC…Macon, GA…
15 % 82,670 12,969,607 Atlanta, GA…Birmingham, AL…Columbus, GA…Huntsville, AL…Chattanooga, TN…
10 % 96,170 14,611,391 Indianapolis, IN…Nashville, TN…Cincinnati, OH…Lexington-Fayette, KY…Louisville, KY…
5 % 145,835 20,161,059 Charlotte, NC…Raleigh, NC…Norfolk, VA…Greensboro, NC…Chesapeake, VA…
2 % 58,628 7,655,933 Columbus, OH…Virginia Beach, VA…Richmond, VA…Newport News, VA…Hampton, VA…

Model Analysis

A highly amplified trough will be present across the Plains at the beginning of Wednesday morning.  This trough will move eastward to the Mississippi Valley by Wednesday evening and continue to the Ohio and Tennessee River Valleys and Southeast by early Thursday morning. Strong mid-level southwesterly winds will overspread much of the Ohio and Tennessee Valleys and Southeast during peak daytime heating.  These winds will then overspread much of the East Coast Wednesday evening through Wednesday night.

Gulf moisture will move northward across portions of Mississippi, Alabama and Georgia this morning.  This moisture will shift eastward across Georgia into the Carolinas and Virginia through the afternoon and early evening before strengthening further late Wednesday into early Thursday morning across the Mid-Atlantic.

The corridor of strong south to southwesterly low-level winds will also overspread much of the Ohio and Tennessee Valleys through by Wednesday night as a warm front advances northward. An area of low pressure initially over southeastern Missouri will develop northeastward into Illinois and Indiana by Wednesday evening.  This strengthening low will then slowly continue northeastward to the vicinity of the eastern Great Lakes by Thursday morning.

A cold front associated with this low will move eastward across the Ohio and Tennessee Valleys and Southeast Wednesday, reaching the Mid-Atlantic by Thursday.

Severe Thunderstorm Watch

A Severe Thunderstorm Watch has already been issued this morning and additional watches are expected as the day goes on.  Large hail is the primary risk with these storms but a tornado cannot be ruled out.

Southeast into the Mid-Atlantic

A very moist warm sector with low 70s F dewpoints will reside south of northward-advancing warm front across the Gulf Coast states.  Warm air advection should cause convection to form along the warm front early Wednesday morning across parts of eastern Mississippi, Alabama, and Georgia. This initial activity will pose a threat for all severe hazards, including tornadoes along and south of the front where surface-based convection will be more likely.  Additional supercell development appears likely within the broad warm sector across the central Gulf Coast States, particularly across Alabama into Georgia and South Carolina Wednesday morning and afternoon as large-scale ascent associated with the upper trough begins to overspread the region.

Forecast soundings across this region suggest strong tornadoes will be possible with any discrete storm that can form in this environment, in addition to very large hail and damaging straight-line winds.  Severe probabilities have been increased and expanded slightly into western Alabama and eastern Mississippi with latest model guidance showing convective development both Wednesday morning along the warm front and again Wednesday afternoon along the cold front.

As the convection that develops Wednesday morning and early afternoon moves across the Carolinas in the evening, instability will increase and result in strong to severe storms across parts of the Carolinas into southeastern Virginia.  If convection can become surface based in this region, then all severe hazards may occur, including a threat for tornadoes.  Severe probabilities across the Carolinas and southern Virginia have been increased to account for this threat late Wednesday night.  Organized Thunderstorm development is expected across the Mid-Atlantic on Thursday as this brings gulf moisture up ahead of the cold front.

 

   Ohio and Tennessee River Valleys

The northward advance of low-level moisture will be more limited across the Ohio and Tennessee Valleys Wednesday, but will still be more than sufficient with dewpoints near 60F ahead of the approaching cold front.  A band of supercells appear likely per latest model guidance.  These storms should be capable of producing tornadoes, very large hail and strong damaging winds.  Eventual growth into mixed modes with line segments may occur during the evening as activity approaches the Appalachians.

Dangerous Storms Sunday

All the parameters are coming together for an active day across a large portion of Texas and Louisiana on Sunday. Currently, isolated severe storms are occurring north of the Texas Hill Country, and a few isolated severe storms are possible across central and northern Texas overnight. Large hail, damaging winds, and an isolated tornado or two are possible. There’s a slight risk of severe thunderstorms for parts of central and southwest Texas. These storms could cause major damage so make sure you check your house after the storm has passed. If you see you need something like an austin residential roof repair company to fix your roof, sort it out quick before the next storm hits.

SPC Thunderstorm Outlook (Tonight)

The bigger impact event will begin to take shape around sunrise on Sunday and continue throughout the day. Much of eastern Texas, northern Texas, southern Oklahoma, southern and central Arkansas, and Louisiana have the chance to see severe thunderstorms–including strong tornadoes in some areas (more on this later in the article). The Storm Prediction Center has a moderate risk (a category 4 on a scale of 1 to 5–with five being the most significant category) for eastern Texas and western Louisiana.

SPC Thunderstorm Outlook (Sunday)

Regional SPC Severe Map From Houston/Galveston NWS (Sunday)

A surface-low will move across Texas tomorrow morning into the afternoon hours. This will lift a warm-front into southern portions of northern Texas. Dewpoints to the south of this boundary will be well into the 60s with mid 70s closer to the coast. A potent upper-level low will begin to approach Texas at the same time. CAPE values should be around 2000 J/Kg or greater, and no CAP. This means storms should develop quickly around sunrise just south of the warm-front and will not be elevated to the south of the warm-front.

All storms south of the warm front on Sunday morning will have a great potential to produce severe weather. Tornadoes, very large hail, and damaging winds are possible. The helicity values will favor rotation, thus, likely enhancing the tornado threat from Tyler, Texas to just south of Dallas to about Waco, Texas–and points south and east. The southern and eastern parts of Texas and western Louisiana have the best chance of seeing a strong tornado or two with discrete thunderstorms.

Highest Tornado Threat Sunday Early Morning-Afternoon (Firsthand Weather)

Locations north of the warm-front (north of the DFW Metro and southern Oklahoma will see a hail threat and possible gusty winds). It should be noted, however, that all of north Texas and even southern Oklahoma does have a severe threat, too, just not a high tornado threat. The severe threat will shift shift eastward throughout the day towards the Arklatex area, and eventually into the Mississippi Valley late in the day on Sunday. The storm mode should favor discrete development, transitioning into a squall line for eastern Texas–with isolated discrete cells developing ahead of the squall line just south of the warm-front.

A second area of thunderstorms could develop across north Texas and Oklahoma later on in the day on Sunday as the upper-level low moves across the area. These storms will produce heavy rainfall and possibly hail. It should also be noted, precipitation amounts will be copious tomorrow. Flash flooding is possible across much of the areas mentioned in this article with the greatest chances occurring in highly urbanized areas due to the impervious surfaces (Austin, Dallas, Houston). Please make sure you have a plan in place, and stay weather alert tomorrow. No need to panic, just be prepared to seek shelter if a warning is issued for your area. I will have an update tomorrow morning.