Severe weather moves from the Plains towards the Mid-Atlantic

Severe weather is a risk over the next couple of days from the Plains and Gulf Coast regions into the Appalachians towards the Mid-Atlantic.  While there is a low risk for tornadoes, there are significant risks for widespread damaging winds and  large hail.

A stationary front has been the focus for strong to severe thunderstorms over the Plains in recent days bringing over 900 reports of severe hail and wind from Texas to Wisconsin.  This front is interacting with a strong, fast moving cold front that will create the lift needed for a large area of showers and thunderstorms.  Some of these storms could be intense this morning as remnants of a Mesoscale convective system died out overnight across the Plains persists.  The severe weather moves on into the Appalachians by Sunday, and on to the Mid-Atlantic up into New England for Monday.

Saturday

The cold front, along with a strengthening low pressure system, will continue to progress southeastward from Central Iowa into Central Kansas.  The air ahead of this front remains warm and unstable with plenty of moisture.

Storms are likely to begin over Iowa and northern Kansas before spreading East from Michigan down into Missouri.  These thunderstorms are expected to form into linear squall lines over time due to weak low level shear yielding outflow dominant storms.    Any storms should begin to weaken after nightfall as they move east, where lapse rates will be lower.

Sunday

Scattered thunderstorms, with a primary risk of damaging winds, are expected from the Great Lakes into Northeast Texas.  The low pressure from Saturday will move from the Great Lakes into Canada but the cold front will remain across the Ohio Valley into the Southern Plains.

From the Great Lakes down through Tennessee, early remnants from overnight storms should clear with a moisture rich warm air-mass in place to meet the weakening cold front.  The ongoing wind regime should allow for strong multi-cluster cells to form.  Hail may also fall but will only be locally severe.

Further south, storms will be more isolated from the Texoma region into Arkansas.  Lift in this region will be weaker but the cold front will be a focus point for thunderstorms due to an elevated mixed layer and moist low level conditions.  These will form a very unstable boundary layer that could see the convective available potential energy (CAPE) approach 4000 Joules per kilogram.

In Mississippi and Alabama, scattered thunderstorms will develop during the daytime heating period.  Seasonably warm and moist air will become more unstable under conditions that have very little convective inhibition.  Strong to severe cells that do form will likely have marginally severe hail and localized damaging winds.

All southern storms should begin to weaken during the evening hours as daytime heating fades.

Starting off the work week, the Northeast and Mid-Atlantic are looking at pending severe weather as the cold front pushes east into more warm moist air Monday afternoon into the overnight hours effecting all the major metropolitan areas.

Rob

 

 

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 shifts east into the River Valleys

An upper low currently crossing eastern Kansas is forecast to accelerate eastward across Missouri and into the Midwest by tonight.  This system, along with a shortwave trough moving into the Gulf of Mexico will quickly shift a cold front across the southeast.  This front is expected to be span from the Ohio Valley down to the Florida panhandle by Friday morning.

Current Conditions

 

Currently, the last of the Tornado Watches has expired.   Strong to severe thunderstorms continue to shift east through Louisiana and Mississippi with a few strong storms up in Illinois.  The storms in Illinois should weaken this morning,  but the southern storms across the gulf states will remain locally severe.

Cloud cover from the current storms will help limit some of the day time heating this afternoon.  The Storm prediction center had a moderate risk area in the forecast yesterday.   This has been downgraded to enhanced this morning.  Do not be surprised if a smaller area of moderate risk re-appears this afternoon as the location of the most destabilization becomes obvious.   The entire area should see at least some instability along and ahead of the cold front, which should be along the Mississippi River by Midday. This front will shift east and provide the mechanism by which storms will form.

Severe Risk

New storm development is expected my early to mid afternoon.  Rotation should be limited with height, but speed shear should generate enough rotation to make tornadoes a risk for a large area as rotating supercells and small bow echoes become possible, particularly over the lower Ohio Valley.

Expect hail and strong winds to remain a risk from this afternoon into the overnight hours near the Appalachians.  The risk will shift even further east into the D.C. area by Friday.  The system should be much weaker with a lower risk for severe weather at that time.  The northeast will even be experiencing snow Friday into the weekend.

Severe weather risk continues for the next few days

After yesterday’s severe weather across parts of Oklahoma and Texas, storms have spread to the east.  Severe Thunderstorm watches are in effect across several states from now until tonight.

Severe Risk

A trough across Missouri this morning moved eastward to the middle Ohio River Valley and will arrive by late tonight. A belt of 40-50 kt west-southwesterly mid level winds will continue to overspread an increasingly moist warm sector. A cold front has moved across the Ozarks and Ark-La-Tex region and continues east through Kentucky and Tennessee down to the Gulf Coast.  Organized convection across far northeast Arkansas far southeast Missouri from late this morning has spread east-northeastward and increased in coverage and intensity into Tennessee and Kentucky. This activity will pose a damaging wind and severe hail risk, although a tornado cannot be ruled out.

Farther south, more discrete storms have developed within the warm sector this afternoon across additional portions of Tennessee, northern Mississippi and northwest Alabama.  A supercell-favorable wind profile and steep mid-level lapse rates will support large hail potential. A few tornadoes also appear possible,  particularly into early evening across middle portions of Tennessee and northern Mississippi and northwest Alabama.   In this corridor, a modest westerly component of the mid-level winds  and modestly strong low-level shear coincide.

Severe

Tornado Risk

Hail Risk

Wind Risk

Current Watches

A Convective line stretching from near Huntingburg Indiana southward across central Kentucky and middle Tennessee and into northwest Alabama is expected to continue moving eastward over the next few hours. The downstream airmass is generally cooler and has less overall instability. However, the line is well-organized and the bulk shear
is expected to remain relatively constant for the next several hours. Near-severe gusts have been measured at several sites as the line moved through. The ongoing severe threat will persist for the next few hours.  A threat is possible downstream in eastern Kentucky, Tennessee and far northwest Georgia and a watch has been issued for this region.  Additionally, the cluster of storms ahead of the line in eastern Kentucky pose an isolated hail and damaging wind threat.

Current warnings

 

 

Robert Millette

 

Tornado Outbreak expected in Southeast

A significant Tornado outbreak and Severe Thunderstorm outbreak is expected across many areas in the Southeast, from Florida back into Alabama up through Georgia, South Carolina and parts of North Carolina.    The biggest risk is from northern Florida into Southern Georgia with smaller risks as far west as Eastern Mississippi up into Southern Virginia.

Tornado Outbreak forecast

Significant Severe Tornadoes expected

Tornado Outbreak
Day 1 Tornado Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
SIG SEVERE 95,336 13,200,743 Columbia, SC…Charleston, SC…

St. Petersburg, FL…Orlando, FL…

Savannah, GA…Gainsville, FL

30 % 52,311 4,824,800 Jacksonville, FL…Tallahassee, FL…

Savannah, GA…Gainesville, FL…

Albany, GA…

15 % 44,337 9,370,344 Tampa, FL…St. Petersburg, FL…

Columbia, SC…Clearwater, FL…

Charleston, SC…

10 % 42,022 5,926,863 Orlando, FL…Columbus, GA…

Fayetteville, NC…Wilmington, NC…

Lakeland, FL…

5 % 81,803 21,852,295 Charlotte, NC…Atlanta, GA…

Miami, FL…Raleigh, NC…

Greensboro, NC…

2 % 48,102 6,722,417 Virginia Beach, VA…Norfolk, VA…

Birmingham, AL…Chesapeake, VA…

Winston-Salem, NC…

High Risk issued for Severe Weather

Categorical Day1 1300Z Outlook
Day 1 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
HIGH 52,325 4,828,034 Jacksonville, FL…Tallahassee, FL…

Savannah, GA…Gainesville, FL…

Albany, GA…

MODERATE 44,236 9,345,964 Tampa, FL…St. Petersburg, FL…

Columbia, SC…Clearwater, FL…

Charleston, SC…

ENHANCED 54,540 8,455,690 Orlando, FL…Columbus, GA…

Cape Coral, FL…Fayetteville, NC…

Port St. Lucie, FL…

SLIGHT 68,779 19,272,935 Charlotte, NC…Atlanta, GA…

Miami, FL…Raleigh, NC…

Greensboro, NC…

MARGINAL 58,080 13,692,306  

Virginia Beach, VA….

Norfolk, VA…

 

 

 

 

 

 

 

 

 

A strengthening mid and upper level trough currently over Texas and Oklahoma will shift eastward into Mississippi and Alabama by this afternoon with a cold front surging east from Louisiana and Mississippi.    This storm will deepen and move north-northeastward across Alabama and Georgia.  Dewpoints ahead of this cold front are already in the 65 to 70 degree range with very buoyant air present.  The net result of these factors will be the potential for a significant tornado outbreak today.

Severe Weather is currently taking place across parts of Alabama, Georgia and Florida and a Tornado Watch is in effect until 10 AM EST.  Cluster of severe storms remain from the overnight hours and the storm environment remains favorable for supercell development.  A few tornadoes are likely and they could be intense.  Damaging winds and Large hail are also possible with these storms.

Additional watches should be expected during the day today.

While the current storms across Georgia are present, the main risk does not occur until later this morning, when thunderstorm activity will begin again over Southern Alabama and the Florida panhandle.  These storms will the spread east-northeast across Florida and Georgia through the day.  Long tracked, strong tornadoes will be possible in fast moving supercells, in addition to damaging winds and large to very large hail.  The severe risk will spread northeastward into the Carolinas this evening as the system moves toward the Southern Appalachians.  Tornadic supercells could continue to occur in south Carolina and Southern North Carolina during the overnight hours.

Further South, the cold front will reach the remainder of Florida later this evening and overnight and bring the risk of severe thunderstorms and a few tornadoes.

Any and all preparations for this event should be concluded by early this afternoon.   This will be a very dangerous situation for many people.   Please be prepared and ready at a moments notice.   We here at Firsthand Weather will do our best to be with you every step of the way this afternoon but keep your weather radios handy and pay attention to your local news broadcasts for updates on warnings that occur.    Facebook likes to prevent you from seeing our page if we post a lot of posts, as we likely will this afternoon.   To see what we are writing, you will need to go directly to our facebook pages and website, please do not count on your newsfeed to give you our information.

 

Robert Millette

 

Severe Weather for Southeast, fires continue

Severe Weather will come with rain as drought conditions are still going strong despite the recent rains.  It cannot be emphasized enough that the fires that saw 3 lives end in Tennessee can still continue over the coming days.    Arson investigations have been opened in some of these fires as investigators begin to determine how the fires started but fire conditions will not take long to return to areas once the rains pass so please remain vigilant in your daily activities when fire is involved.  To all of our readers and their neighbors in these regions,  stay safe and plan ahead.   As seen in Gaitlinburg, these fires can come very quickly.  Prepare in advance and be ready to leave at a moments notice with multiple escape routes as options.

drought-monitor

Rain will continue in the southeast tonight into Wednesday from Extreme Eastern Texas over the South Florida along the gulf up north through Arkansas into the Ohio Valley and Great Lakes regions.  Additional precipitation is possible in New England with freezing rain advisories issued for the higher and more northern elevations.  Severe Weather, including Flash Floods and Tornadoes are possible tonight and will be addressed in this post.

A slowly weakening low pressure system across the northern plains and Upper Midwest will continue to bring potentially heavy snow to the Dakotas into this evening, before snow begins to gradually taper off overnight. Scattered snow and some rain showers will still be possible across the northern plains and Upper Midwest into Wednesday.

Farther east, widespread rain and even some thunderstorms are expected tonight and Wednesday from the lower Mississippi valley to the Northeast. Some areas of heavy rain are possible across portions of the lower Mississippi and Tennessee valleys through tonight as some significant rains have already fallen in the area.

nws_precip_se_1

The showers and thunderstorms will reach the East Coast on Wednesday, with thunderstorms possible from the Southeast to the southern Mid-Atlantic region. By late in the day, snow is expected to develop across northern Maine as the precipitation spreads into colder air already in place. Snow may be heavy
at times Wednesday night into Thursday.

noaad1

Strong low pressure seen here moving into Canada has dragged a cold front south draped down into the Carolinas.  This weakening front brought the region last nights rain.  A second cold front associated with this low is now moving through Illinois down into Texas.  This front, along with a developing warm front moving north from the gulf are what will set the stage for tonight’s Severe Weather risk

Severe Weather Returns

severe weather

Day 1 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
MODERATE 13,427 585,227 Tupelo, MS…Starkville, MS…Greenwood, MS…Grenada, MS…Oxford, MS…
ENHANCED 42,707 2,601,397 Baton Rouge, LA…Jackson, MS…Monroe, LA…Greenville, MS…Florence, AL…
SLIGHT 113,393 11,559,771 Nashville, TN…New Orleans, LA…Birmingham, AL…Mobile, AL…Huntsville, AL…
MARGINAL 49,543 6,567,755 Memphis, TN…Lexington-Fayette, KY…Montgomery, AL…Knoxville, TN…Beaumont, TX…

The storm prediction center has upgraded a small region in Northern Mississippi to a moderate risk while large portions of the south east remain in an enhanced or slight risk area.  The  risk for Tornadoes is large tonight and Tornado watches have already been issued for several counties.

severe-watch

Day 1 Tornado Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
SIG SEVERE 56,076 3,179,960 Baton Rouge, LA…Jackson, MS…Monroe, LA…Greenville, MS…Tupelo, MS…
15 % 13,456 588,577 Tupelo, MS…Starkville, MS…Greenwood, MS…Grenada, MS…Oxford, MS…
10 % 42,678 2,598,047 Baton Rouge, LA…Jackson, MS…Monroe, LA…Greenville, MS…Florence, AL…
5 % 70,735 7,846,202 Nashville, TN…New Orleans, LA…Birmingham, AL…Huntsville, AL…Metairie, LA…
2 % 43,513 4,379,865 Chattanooga, TN…Clarksville, TN…Beaumont, TX…Gulfport, MS…Lake Charles, LA…

The risk for significant tornadoes exists from Baton Rouge and Monroe Louisiana north towards Florence Alabama and just south of Nashville Tennessee, however, tornadoes can be expected from Beaumont Texas right up into Central Kentucky.

Current Tornado Watches

tor-watch-1 tor-watch-2

These watches extend from near Alexandria Louisiana to almost Jackson Tennessee and include Monroe Louisiana and Jackson and Tupelo Mississippi.  Memphis Tennessee remains just north east of the watch area but Tornadoes can occur outside the watch boxes so vigilance must be maintained.

The latest radar imagery show several strong and locally severe storms ongoing across the Lower Mississippi Valley area.  Advection will continue to occur across the Central Gulf Coast States and move into the Tennessee Valley as an upper level system approaches.  The Severe Weather and Tornado risk will spread northward with time.

firsthand Weather expects that Tornado Watches will continue to be expanded northeastward into further into Tennessee as scattered supercells in Mississippi move in that direction this evening.  Northeast Alabama and Tennessee should begin to see the impacts of these storms this evening into the overnight.  The environment is becoming more favorable for rotating storms as the evening goes on, especially in Northeast Mississippi.  Large hail and damaging winds will also be a risk tonight.

 

 

Robert Millette

Firsthand Weather

 

 

Severe weather to strike again in Northeast

The severe weather simply refuses to quite down in the Northeast as we move into what we expect to be our third day of severe weather in 4 days.  The past week has seen New England experience 4 Tornadoes in New Hampshire and Maine, though all were thankfully weak and In mostly uninhabited regions.

Currently, a shortwave trough moving through Ontario is expected to move into Southern Quebec by Monday.  A mid-level disturbance is moving around the bottom of this shortwave and the disturbance will induce height falls at the 500 millibar level through Monday afternoon into Monday night, increasing the overall instability of the region.  A cold front associated with the trough will move through the Great Lakes region into New England with the trailing southern portion extending through the Ohio River Valley back into Arkansas and Oklahoma.

image

Severe Summary

Southwesterly flow ahead of the trough and cold front has been working to moisten the air across Pennsylvania and New York.  This moist air is spreading into the Hudson River Valley and will expand across much of Western and Southern New England through Monday afternoon.  Dew points are expected to climb well into the 60s at the surface with some locations approaching 70 degrees.  There will be an elevated mixed layer between 700 and 500 millibars that should spread east atop this moist air which should allow for cumulonimbus clouds to build to very high heights for this area, especially across Central and Eastern New York, Northeast Pennsylvania and Western areas of New England.

There may be some limiting factors to overall destabilization if some early period convection and cloudiness occurs to limit day time heating, but moderate to high mid to upper-level cape (convective available potential energy) and strong forcing from the cold front is expected to help overcome any deficiencies that may occur from areas of limited heating.  Strengthening deep layer shear is also going to be a factor and the increasing shear conditions over New York and Northern Pennsylvania as well as Western and Central New England should bring higher severe weather risks.

Strengthening westerly winds with height suggest organized storms will be possible, with some splitting of storms occurring.  Damaging winds will be the primary threat though some hail cannot be ruled out.

 

Robert Millette

Staff Meteorologist

Firsthand Weather

 

Severe weather comes to the Northeast

Severe

Severe weather threat for the Northeast

Severe weather is expected today in the Northeast and the Storm Prediction Center has out most of the region under a slight risk from eastern New York and northeast Pennsylvania up trough all but the south coast of New England   Remaining locations in the aforementioned region are under a marginal risk for severe weather.

Severe

Summary

Damaging winds and hail are the primary threats as a cold front moves through the region.   Dry conditions are impacting some areas to the north but southerly flow is moistening some areas through the day.

A shortwave trough, now evident in moisture channel imagery, is shifting east through Canada.  This system is bringing a cold front southeast, stretching across New England into the Great Lakes.

This frontal boundary, along with a wind shift from Maine down to the mid-Atlantic will be the primary focus areas for thunderstorm development from mid afternoon into the early overnight hours.

Deep shear is expected to strengthen this afternoon along with upper level height falls as the system approaches this afternoon.   These factors should occur at the same time as the maximum heating and boundary layer destabilization and could lead to supercell and multicellular cluster development.  Early cloudiness was not a major factor as temperatures are climbing into the low 90s to upper 80s in the majority of locations.

Should storms occur in your area, please remember than dangers that thunderstorms and flooding conditions can bring.  If you can hear thunder, you can be struck by lightning and even a small amount of water can float even heavy vehicles.

Stay here with firsthand weather for updates on this developing situation and also keep advised of your NOAA radio or local media sources for instant coverage of warnings in your localities.

Robert Millette

Staff Meterorologist

Firsthand Weather

Severe weather threatens the Northeast

Severe

Severe weather threatens as a long lived linear mesoscale convective system continues eastward across Lower Michigan, strong heating ahead of the system should result in re-intensification of storms along the leading edge this afternoon.  This system should hold together to cross Lake Erie into Ohio and Pennsylvania before spreading into New England overnight.

By Friday, a belt of moderately strong mid-level flow will move into the northeast ahead of an advancing cold front.  This cold front should reach eastern New England by Friday evening into Friday night and extend westward into the southern Great Lakes region.

Severe weather summary

Scattered severe storms are forecast Friday into Friday night across Eastern New York and New England.  Isolated strong to severe storms are expected through parts of central and western New York, New Jersey, and Pennsylvania into the southern Great Lakes region.

Severe

Considerable uncertainty exists regarding the impact of the ongoing mesoscale convective system as it moves east.  This system is expected to weaken overnight but considerable cloudiness will exist with the systems remnants and those may prevent destabilization in certain areas ahead of the front.  The areas where these clouds are most prevalent are the areas that will see less destabilization.    Models do indicate low level moistening ahead of the cold front with strong southerly flow contributing to the amount of buoyancy that develops in the region.   Strong westerly flow aloft, which will increase with height, will support organized storms.  These may include supercell and a muticellular clusters primarily during the late afternoon and early evening hours.   Wind and hail appear to be the primary threats but a tornado like the one this past week in New Hampshire cannot be ruled out in the most intense storms.  Another article should be out Friday morning to bring you all the latest information.

 

Robert Millette

Staff Meteorologist

Firsthand Weather

Severe weather risk for the Upper Midwest

Severe weather is currently active over the Northern Plains with a tornado watch and multiple severe thunderstorm watches active this evening.

Summary

A potent shortwave trough is moving across the Northern Plains this afternoon and is expected to move towards the Upper Mississippi Valley by Friday.  Currently, the greatest threat for severe weather exists from the  Black Hill region of the Dakotas East and Southeast across the Mid-Missouri Valley.  Strong and damaging wind gusts, very large hail and a few tornadoes are expected.   Multiple Mesoscale Convective systems from these severe storms will continue to progress further East from the Midwest down to the Carolinas  and Georgia.

severe outlook

Day 1 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
MODERATE 35,708 282,582 Mitchell, SD…Pierre, SD…Yankton, SD…Vermillion, SD…
ENHANCED 90,604 4,130,773 Nashville, TN…Des Moines, IA…Sioux Falls, SD…Clarksville, TN…Sioux City, IA…
SLIGHT 214,768 10,921,413 Omaha, NE…Lexington-Fayette, KY…Lincoln, NE…Savannah, GA…Cedar Rapids, IA…
MARGINAL 372,120 43,514,822 Columbus, OH…Memphis, TN…Charlotte, NC…Kansas City, MO…Cleveland, OH…

Tornado Watch Active

tornado outlook

THE NWS STORM PREDICTION CENTER HAS ISSUED A TORNADO WATCH FOR

Northern Nebraska, Western South Dakota and Far Northeast Wyoming until 10 PM CDT.

 

A few more tornadoes are likely with a couple of intense tornadoes possible.  Currently, there is an active Tornado Warning for a tornado on the ground in cherry County Nebraska.  Widespread Large hail and isolated very large hail to 3.5 inches in diameter likely and widespread damaging winds likely with isolated gusts to 80 MPH possible.

Intense thunderstorms, including Supercells and Supercell clusters have formed over the watch area and are moving towards the Eastern portion of the watch area.  South of this watch area, the Tornado risk is much smaller and a Severe Thunderstorm Watch is in effect until 10 PM CDT.  Squall line development is expected from the storms further north in the Tornado watch area.  This squall line will move into Central and Southern Nebraska and move toward the Southeastern and Eastern portions of this watch area.

tornado outlook

Further North,   a line of storms from Montana has moved into the Dakotas.  The severe thunderstorm watch for this area is slowly being cancelled from west to East but remains in effect for the Western Dakotas until 9 PM CDT.

 

Severe Thunderstorm Watches are in effect for a small portion of Central Tennessee, this watch should be cancelled shortly.

 

Thursday Severe Risk

severe outlook

Day 2 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
ENHANCED 120,618 9,748,278 Minneapolis, MN…Des Moines, IA…Cedar Rapids, IA…Springfield, IL…Peoria, IL…
SLIGHT 206,214 34,063,611 Chicago, IL…Indianapolis, IN…Milwaukee, WI…Omaha, NE…St. Louis, MO…
MARGINAL 347,083 42,004,487 Detroit, MI…Columbus, OH…Charlotte, NC…Nashville, TN…Kansas City, MO…

A complex setup is set for Thursday with multiple rounds of convection expected across a large region.  Clusters of severe thunderstorms will be likely within a Mesoscale Convective System over Iowa and  Southern Minnesota.  Downstream of this area, dew points  in the 70s will combine with daytime heating to form a moderately to strongly unstable air mass through the day. This set up should yield multiple clusters of intensifying storms from the late morning into the afternoon across parts of the Midwest.

In the wake of the morning activity, low level moisture should return on the Southwesterly flow underneath the elevated mixed layer.  Moderate to extreme mid-level cape could help generate another mesoscale convective system Thursday evening in the Iowa, Missouri, Illinois border area.

Farther north, strong mid-level winds associated with the trough will overspread Minnesota where strong instability already exists.  While instability does decrease the further north you go, scattered to widespread storms should form mid-afternoon to early evening.  Deep shear will be sufficient for organized strong clusters and embedded supercells.  Large hail and strong winds will be the primary risks.

Robert Millette

Staff Meteorologist

Firsthand Weather