SPC 2000Z Day 1 Outlook

Day 1 Convective Outlook  NWS Storm Prediction Center Norman OK0242 PM CDT Sat Mar 29 2025Valid 292000Z - 301200Z...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THECENTRAL AND SOUTHERN GREAT PLAINS INTO THE MIDDLE MISSISSIPPIVALLEY......SUMMARY...Scattered severe thunderstorms are possible across parts of thecentral/southern Plains into the mid Mississippi Valley, mainly thisevening through the overnight hours. This may include an organizedthunderstorm cluster across parts of Oklahoma into southeasternKansas and western Missouri capable of producing very large hail,damaging winds, and perhaps a couple of tornadoes....20z Update...The Marginal Risk across portions of southeast Texas was to remove,as thunderstorm activity has moved eastward. A Marginal Risk wasintroduced across the Florida Keys. Otherwise, no changes were madeto the Slight Risk areas across the southern/central Plains. Seeprevious discussion for more information....Central Plains into the Mid Mississippi Valley...As thunderstorm activity progresses eastward through time thisevening, a corridor of greater damaging wind risk may develop. CAMsolutions continue to indicate upscale growth across portions ofnorthern Oklahoma into southern Kansas and western Missouri. Shouldthis line be able to organize and establish a strong cold pool, thepotential exists for a swath of damaging wind and perhaps somesignificant winds given the steep mid-level lapse. Limiting factorsinclude the displacement of the stronger low-level jet winds to thesouth and lagging of stronger mid-level flow across the Red Riverinto central Oklahoma. In addition, CAM guidance is split on a moreorganized bowing line or a somewhat broken line of mixed modethunderstorms. Even so, a couple of gusts 70-80 mph could not beruled out. ...Florida Keys...Recent radar imagery has shown a couple of supercells withstrengthening rotation moving northwestward near the lower FloridaKeys. The environment in this region is characterized by richmoisture and storm relative helicity around 100-150 m2/s2. This willsupport a risk for a tornado with inclusion of a Marginal Risk withthis update...Thornton/Smith.. 03/29/2025.PREV DISCUSSION... /ISSUED 1134 AM CDT Sat Mar 29 2025/...Central/Southern Plains into the Mid Mississippi Valley...Water-vapor imagery shows a lead disturbance moving northeastwardacross the central Great Plains towards the Upper Midwest, while anupstream disturbance moves from eastern AZ into the southern GreatPlains tonight.  The primary surface low over western KS thismorning is forecast to develop east-northeastward towards southernIA/northern MO by tonight.  An attendant cold front will sweepsouthward across parts of the central/southern Plains through theperiod, while a dryline mixes eastward over the southern High Plainsthis afternoon.Surface analysis shows lower 60s dewpoints streaming northward onsoutherly low-level flow this morning from north TX to the KS/OKborder.  A substantial cap will likely inhibit robust convectivedevelopment until late this afternoon or early evening, with thecold front/dryline intersection over western OK a potential locationfor convective initiation by 23-03Z as large-scale ascent with thetrailing shortwave trough overspreads the warm sector. Moderate to strong buoyancy will likely be present acrosswestern/northern OK and southern KS, with steep mid-level lapserates atop upper 50s to mid 60s surface dewpoints.  Forecastsoundings favor supercell development with activity that developssouth of the front across west-central OK.  Large to very large hail(potentially up to 1.5-2.5 inches in diameter) may accompany thesestorms early in their convective life cycle.  Despite increasingCINH during the evening, lower 60s dewpoints in place with 500-mbtemperatures around -15 deg C may aid the development of a tornadorisk from central into northeast OK as storms mature and eventuallygrow upscale.  Severe gusts will probably become more prevalent withtime as this cluster moves east-northeast into parts of northeast OKand eventually into MO later tonight, perhaps with the wind threatslowly diminishing late.  Farther south, a conditional severe threat exists south of the RedRiver from north TX southwestward into parts of the Concho Valley. It appears the airmass will remain capped during the day in thevicinity of the dryline, with storm development likely delayed untillate evening into the overnight per recent model guidance.  Verysteep 700-500 mb lapse rates, strong deep-layer shear magnitudes (50kt effective shear), and 2000-3000 J/kg MUCAPE will support a severerisk with any sustained storms.  Models vary between very isolatedcoverage and scattered storm coverage, especially over parts ofcentral into north TX.  Given consistency in some model guidance(e.g., HRRR model run to run, GFS, ECMWF) showing some convectivesignal, have opted to increase hail probabilities to level-2 SlightRisk overnight.  Large to very large hail is possible with thestronger storms (1 to 2.5 inches in diameter)....Louisiana/Mississippi...A remnant MCV will continue to move northeastward this afternoonacross the lower MS Valley and Mid-South.  Although deep-layer shearis expected to remain fairly weak, sufficient low-level shear shouldbe present to support some updraft organization and transientrotation with the stronger storms.  Cells movingnortheastward and inland over the central Gulf Coast may pose athreat for a brief tornado, as well as a localized risk for damaginggusts.

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SPC 1930Z Day 3 Outlook

Day 3 Convective Outlook  NWS Storm Prediction Center Norman OK0227 PM CDT Sat Mar 29 2025Valid 311200Z - 011200Z...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS A LARGEPART OF THE EASTERN U.S. INTO THE CENTRAL GULF COAST......SUMMARY...Strong/severe thunderstorms are forecast Monday from portions of theNortheast southwestward to the central Gulf Coast region....Synopsis...A surface low is forecast to intensify as it moves northeastwardfrom the Lower Great Lakes into southeast Canada through the dayMonday morning in tandem with a leading shortwave trough. A trailingcold front is expected to push east/southeast into the upper OHRiver Valley and lower MS Valley/Southeast early Monday morning as asecond low-amplitude wave traverses the eastern CONUS. Thunderstormpotential will be focused along this front as it continues to pushinto New England, the Mid-Atlantic, and into the southeast statesthrough the late afternoon and evening hours. ...Central Gulf States...Strong to severe thunderstorms may be ongoing by 12z Monday as asquall line forced along the cold front continues to push southeastacross MS and AL. A combination of rich low-level moisture ahead ofthe line, diurnal heating, strong low to mid-level flow, and broadscale ascent ahead of the secondary upper wave should help maintainconvective intensity into the afternoon hours. A corridor ofdamaging/severe winds, and potentially embedded tornadoes, appearsprobable from central MS into AL and western GA....Central Appalachians...Thunderstorm development along the front is expected by early tomid-afternoon from the upper OH Valley southward into theMid-Atlantic region. Returning moisture through the Carolinasnorthward into eastern PA/western NY, combined with mid-level lapserates around 7 C/km, should support sufficient buoyancy for deepconvection, though buoyancy values should diminish with northwardextent across the central Appalachians. Moderate flow within thelowest few kilometers should support a damaging wind threat asconvection matures along the front across the upper OH Valley.Further south, stronger ascent ahead of the secondary upper waveshould promote better storm organization, including the potentialfor semi-discrete cells and/or organized linear segments.Medium-range guidance suggests low-level winds will strengthenacross the Mid-Atlantic region as a weak secondary low deepensthrough late afternoon in the lee of the Appalachians, which maysupport an enlargement of the 0-3 km hodograph and a locally highertornado threat across the Carolinas into VA...Moore.. 03/29/2025

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Public Severe Weather Outlook

PUBLIC SEVERE WEATHER OUTLOOK  NWS STORM PREDICTION CENTER NORMAN OK1136 AM CDT WED APR 02 2025...Outbreak of tornadoes and severe thunderstorms expected overparts of the parts of the Mid-South and the lower Mississippi andOhio River Valleys later today and tonight...* LOCATIONS...  Eastern Arkansas  Western Tennessee  Southeast Missouri  Western Kentucky  Southern Illinois  Northwest Mississippi  Central and Southern Indiana  Northern Louisiana  Western Ohio* HAZARDS...  Numerous tornadoes, several intense and long track  Widespread damaging winds, some hurricane force  Scattered large hail, some baseball size* SUMMARY...  A tornado outbreak is expected this afternoon into early tonight  from parts of the lower Mississippi Valley into the Mid-South  and lower Ohio Valley. Numerous tornadoes, along with multiple  EF3+ tornadoes, appear likely. In addition, tornadoes,  significant severe wind gusts, and large hail to very large hail  will be possible across a broad area from north Texas  northeastward to the southern Great Lakes.Preparedness actions...Review your severe weather safety procedures for the possibilityof dangerous weather today. Stay tuned to NOAA Weather Radio, 

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SPC 1930Z Day 3 Outlook

Day 3 Convective Outlook  NWS Storm Prediction Center Norman OK0227 PM CDT Sat Mar 29 2025Valid 311200Z - 011200Z...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS A LARGEPART OF THE EASTERN U.S. INTO THE CENTRAL GULF COAST......SUMMARY...Strong/severe thunderstorms are forecast Monday from portions of theNortheast southwestward to the central Gulf Coast region....Synopsis...A surface low is forecast to intensify as it moves northeastwardfrom the Lower Great Lakes into southeast Canada through the dayMonday morning in tandem with a leading shortwave trough. A trailingcold front is expected to push east/southeast into the upper OHRiver Valley and lower MS Valley/Southeast early Monday morning as asecond low-amplitude wave traverses the eastern CONUS. Thunderstormpotential will be focused along this front as it continues to pushinto New England, the Mid-Atlantic, and into the southeast statesthrough the late afternoon and evening hours. ...Central Gulf States...Strong to severe thunderstorms may be ongoing by 12z Monday as asquall line forced along the cold front continues to push southeastacross MS and AL. A combination of rich low-level moisture ahead ofthe line, diurnal heating, strong low to mid-level flow, and broadscale ascent ahead of the secondary upper wave should help maintainconvective intensity into the afternoon hours. A corridor ofdamaging/severe winds, and potentially embedded tornadoes, appearsprobable from central MS into AL and western GA....Central Appalachians...Thunderstorm development along the front is expected by early tomid-afternoon from the upper OH Valley southward into theMid-Atlantic region. Returning moisture through the Carolinasnorthward into eastern PA/western NY, combined with mid-level lapserates around 7 C/km, should support sufficient buoyancy for deepconvection, though buoyancy values should diminish with northwardextent across the central Appalachians. Moderate flow within thelowest few kilometers should support a damaging wind threat asconvection matures along the front across the upper OH Valley.Further south, stronger ascent ahead of the secondary upper waveshould promote better storm organization, including the potentialfor semi-discrete cells and/or organized linear segments.Medium-range guidance suggests low-level winds will strengthenacross the Mid-Atlantic region as a weak secondary low deepensthrough late afternoon in the lee of the Appalachians, which maysupport an enlargement of the 0-3 km hodograph and a locally highertornado threat across the Carolinas into VA...Moore.. 03/29/2025

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SPC 0100Z Day 1 Outlook

Day 1 Convective Outlook  NWS Storm Prediction Center Norman OK0755 PM CDT Wed Apr 02 2025Valid 030100Z - 031200Z...THERE IS A HIGH RISK OF SEVERE THUNDERSTORMS FROM SOUTHERNARKANSAS INTO SOUTHERN ILLINOIS......SUMMARY...A tornado outbreak is ongoing across parts of the lower MississippiValley into the Mid-South and lower Ohio Valley. Numerous tornadoes,along with multiple EF3+ tornadoes, remain likely. Additionally,tornadoes, significant severe wind gusts, and large hail to verylarge hail remain possible across a broad area from north Texasnortheastward to the southern Great Lakes....01z Update...An elongated corridor of severe thunderstorms has evolved fromsouthern Arkansas, northeast across the Boot Heel of Missouri intonorthern Indiana. Numerous tornadic supercells are noted along thiszone, especially across the High Risk area from southern Arkansasinto southern Illinois. Multiple long-lived tornadoes have likelyproduced significant damage in places, and this threat will continueinto the late evening/overnight hours.Intense LLJ is forecast to translate across the western TennesseeValley into the lower Great Lakes, and this will contribute to anortheastward shift of organized convection after midnight as theprimary short-wave trough ejects toward lower Michigan.Environmental parameters continue to favor strong tornadoes anddamaging winds, along with large hail.Upstream across Texas, a secondary low-latitude short-wave troughwill approach far West Texas late in the period. In response to thisfeature, LLJ is forecast to increase across the Edwards Plateau by03/06z, and strengthening is expected as the LLJ shifts toward theI35 corridor by sunrise. Significant destabilization is expectedinto north-central Texas late as moisture surges north. As a result,supercells are expected to develop and spread east-northeast...Darrow.. 04/03/2025

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SPC 1730Z Day 2 Outlook

Day 2 Convective Outlook  NWS Storm Prediction Center Norman OK1228 PM CDT Sat Mar 29 2025Valid 301200Z - 311200Z...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS A BROADAREA CENTERED OVER THE OHIO/MID MISSISSIPPI/TENNESSEE VALLEYS......SUMMARY...A widespread/substantial severe-weather episode is forecast acrossan area centered on the Ohio/Mid and Lower Mississippi/LowerMissouri/Tennessee River Valleys.  Very large hail, damaging winds,and strong tornadoes are expected....Synopsis...Mid-morning water vapor imagery depicts an upper-level shortwavetrough across the Southwest that is the leading impulse within alongwave trough building across the eastern Pacific/western CONUS.This wave is expected to overspread the southern/central Plainstoday before migrating into the Great Lakes region through the daytomorrow. A secondary disturbance is expected to move into thesouthern Plains late tomorrow evening into early Monday. At thesurface, the surface low analyzed across KS is forecast to intensifyas it moves northeast along a frontal zone into the Great Lakes intandem with the leading upper disturbance. The intensification ofthe low will result in a cold frontal surge across the Midwest/OHValley tomorrow afternoon and across the Mid-MS Valley to Texarkanaregion tomorrow evening. Scattered to widespread thunderstormdevelopment is anticipated along and ahead of the frontal zone withthe potential for widespread large hail/severe winds and severaltornadoes. ...Central TX...Latest guidance suggests convection may be ongoing across central TXalong/ahead of a migratory dryline early Sunday morning. Thesouthern extent of a pronounced EML casts doubt on stormcoverage/longevity. However, buoyancy and deep-layer wind shearshould be supportive of supercells with an attendant severehail/wind threat if mature updrafts can develop along the boundaryas the primary upper-level trough axis passes over the region....IL, IN, and OH...Consensus among recent forecast guidance is that kinematic fieldswill steadily strengthen across the Midwest and middle OH RiverValley regions through the day as the surface low intensifies.Increasing southerly flow ahead of the primary cold front shouldallow for dewpoints in the upper 50s to low 60s to spread into theregion by mid-afternoon. Scattered thunderstorm development alongthe cold front appears likely as early as 18-20z across IL, andwhile a few initially discrete cells are possible, strong forcingalong the front should promote upscale growth into an organized lineby late afternoon. Strong low-level flow (nearly 50 knots 0-1 kmBWD) may promote bowing segments and embedded mesovorticies withinthe line - especially across northern IN/northwest OH. 30% windprobabilities have been expanded northward to account for thispotential.While this is the most probable scenario based on morning guidance,it could be complicated by any ongoing showers/thunderstorms and/orremnant outflow boundaries associated with nocturnal convection overMO late Saturday/early Sunday morning. This could limit diurnalheating/destabilization or may provide pre-frontal foci forconvective initiation and promote more discrete storm modes.  ...Mid-MS Valley to Texarkana region...Scattered, initially discrete supercells are expected to developfrom the confluence of the OH/MS rivers southwestward into theTexarkana region Sunday afternoon along the cold front and dryline.Strong flow associated with the intensifying cyclone will promoteelongated hodographs featuring nearly uni-directional wind profilesand effective bulk shear values on the order of 50-60 knots. Thiswill promote splitting supercells with the potential for large tovery large (2+ inch) hail. A more appreciable supercellular tornadothreat may emerge through early evening across the lower OHValley/mid-MS Valley where stronger veering in the lowest 1-2 km isanticipated amid weak pre-frontal isentropic ascent between 925-850mb. While the tornado threat may be maximized through this corridor,low confidence in storm mode (due to the potential for splittingcells/destructive interactions) limits confidence in this potentialto warrant higher probabilities at this time.However, upscale growth is anticipated through mid/late evening asthe secondary upper disturbance migrates into the Texarkana region.Consolidation of multiple clusters into one or more organized linearsegments is expected as storms push east towards the MS Valley witha gradual increase in the potential for damaging/severe winds.Additionally, low-level shear will remain favorable for embeddedmesovorticies as the line pushes into western TN/northernMS/northwest AL through the overnight hours. ...Florida...A weak mid-level impulse (currently over the northern Gulf) isexpected to meander across northern FL by peak heating. Somewhatstrong mid-level winds (25-30 knots) associated with this featuremay provide sufficient organization to thunderstorms developingacross eastern central/northern FL to pose an isolated hail/windthreat...Moore.. 03/29/2025

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SPC 1730Z Day 2 Outlook

Day 2 Convective Outlook  NWS Storm Prediction Center Norman OK1228 PM CDT Sat Mar 29 2025Valid 301200Z - 311200Z...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS A BROADAREA CENTERED OVER THE OHIO/MID MISSISSIPPI/TENNESSEE VALLEYS......SUMMARY...A widespread/substantial severe-weather episode is forecast acrossan area centered on the Ohio/Mid and Lower Mississippi/LowerMissouri/Tennessee River Valleys.  Very large hail, damaging winds,and strong tornadoes are expected....Synopsis...Mid-morning water vapor imagery depicts an upper-level shortwavetrough across the Southwest that is the leading impulse within alongwave trough building across the eastern Pacific/western CONUS.This wave is expected to overspread the southern/central Plainstoday before migrating into the Great Lakes region through the daytomorrow. A secondary disturbance is expected to move into thesouthern Plains late tomorrow evening into early Monday. At thesurface, the surface low analyzed across KS is forecast to intensifyas it moves northeast along a frontal zone into the Great Lakes intandem with the leading upper disturbance. The intensification ofthe low will result in a cold frontal surge across the Midwest/OHValley tomorrow afternoon and across the Mid-MS Valley to Texarkanaregion tomorrow evening. Scattered to widespread thunderstormdevelopment is anticipated along and ahead of the frontal zone withthe potential for widespread large hail/severe winds and severaltornadoes. ...Central TX...Latest guidance suggests convection may be ongoing across central TXalong/ahead of a migratory dryline early Sunday morning. Thesouthern extent of a pronounced EML casts doubt on stormcoverage/longevity. However, buoyancy and deep-layer wind shearshould be supportive of supercells with an attendant severehail/wind threat if mature updrafts can develop along the boundaryas the primary upper-level trough axis passes over the region....IL, IN, and OH...Consensus among recent forecast guidance is that kinematic fieldswill steadily strengthen across the Midwest and middle OH RiverValley regions through the day as the surface low intensifies.Increasing southerly flow ahead of the primary cold front shouldallow for dewpoints in the upper 50s to low 60s to spread into theregion by mid-afternoon. Scattered thunderstorm development alongthe cold front appears likely as early as 18-20z across IL, andwhile a few initially discrete cells are possible, strong forcingalong the front should promote upscale growth into an organized lineby late afternoon. Strong low-level flow (nearly 50 knots 0-1 kmBWD) may promote bowing segments and embedded mesovorticies withinthe line - especially across northern IN/northwest OH. 30% windprobabilities have been expanded northward to account for thispotential.While this is the most probable scenario based on morning guidance,it could be complicated by any ongoing showers/thunderstorms and/orremnant outflow boundaries associated with nocturnal convection overMO late Saturday/early Sunday morning. This could limit diurnalheating/destabilization or may provide pre-frontal foci forconvective initiation and promote more discrete storm modes.  ...Mid-MS Valley to Texarkana region...Scattered, initially discrete supercells are expected to developfrom the confluence of the OH/MS rivers southwestward into theTexarkana region Sunday afternoon along the cold front and dryline.Strong flow associated with the intensifying cyclone will promoteelongated hodographs featuring nearly uni-directional wind profilesand effective bulk shear values on the order of 50-60 knots. Thiswill promote splitting supercells with the potential for large tovery large (2+ inch) hail. A more appreciable supercellular tornadothreat may emerge through early evening across the lower OHValley/mid-MS Valley where stronger veering in the lowest 1-2 km isanticipated amid weak pre-frontal isentropic ascent between 925-850mb. While the tornado threat may be maximized through this corridor,low confidence in storm mode (due to the potential for splittingcells/destructive interactions) limits confidence in this potentialto warrant higher probabilities at this time.However, upscale growth is anticipated through mid/late evening asthe secondary upper disturbance migrates into the Texarkana region.Consolidation of multiple clusters into one or more organized linearsegments is expected as storms push east towards the MS Valley witha gradual increase in the potential for damaging/severe winds.Additionally, low-level shear will remain favorable for embeddedmesovorticies as the line pushes into western TN/northernMS/northwest AL through the overnight hours. ...Florida...A weak mid-level impulse (currently over the northern Gulf) isexpected to meander across northern FL by peak heating. Somewhatstrong mid-level winds (25-30 knots) associated with this featuremay provide sufficient organization to thunderstorms developingacross eastern central/northern FL to pose an isolated hail/windthreat...Moore.. 03/29/2025

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SPC 1630Z Day 1 Outlook

Day 1 Convective Outlook  NWS Storm Prediction Center Norman OK1134 AM CDT Sat Mar 29 2025Valid 291630Z - 301200Z...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OFTHE CENTRAL AND SOUTHERN GREAT PLAINS INTO THE MIDDLE MISSISSIPPIVALLEY......SUMMARY...Scattered severe thunderstorms are possible across parts of thecentral/southern Plains into the mid Mississippi Valley, mainly thisevening through the overnight hours. This may include an organizedthunderstorm cluster across parts of Oklahoma into southeasternKansas and western Missouri capable of producing very large hail,damaging winds, and perhaps a couple of tornadoes....Central/Southern Plains into the Mid Mississippi Valley...Water-vapor imagery shows a lead disturbance moving northeastwardacross the central Great Plains towards the Upper Midwest, while anupstream disturbance moves from eastern AZ into the southern GreatPlains tonight.  The primary surface low over western KS thismorning is forecast to develop east-northeastward towards southernIA/northern MO by tonight.  An attendant cold front will sweepsouthward across parts of the central/southern Plains through theperiod, while a dryline mixes eastward over the southern High Plainsthis afternoon.Surface analysis shows lower 60s dewpoints streaming northward onsoutherly low-level flow this morning from north TX to the KS/OKborder.  A substantial cap will likely inhibit robust convectivedevelopment until late this afternoon or early evening, with thecold front/dryline intersection over western OK a potential locationfor convective initiation by 23-03Z as large-scale ascent with thetrailing shortwave trough overspreads the warm sector. Moderate to strong buoyancy will likely be present acrosswestern/northern OK and southern KS, with steep mid-level lapserates atop upper 50s to mid 60s surface dewpoints.  Forecastsoundings favor supercell development with activity that developssouth of the front across west-central OK.  Large to very large hail(potentially up to 1.5-2.5 inches in diameter) may accompany thesestorms early in their convective life cycle.  Despite increasingCINH during the evening, lower 60s dewpoints in place with 500-mbtemperatures around -15 deg C may aid the development of a tornadorisk from central into northeast OK as storms mature and eventuallygrow upscale.  Severe gusts will probably become more prevalent withtime as this cluster moves east-northeast into parts of northeast OKand eventually into MO later tonight, perhaps with the wind threatslowly diminishing late.  Farther south, a conditional severe threat exists south of the RedRiver from north TX southwestward into parts of the Concho Valley. It appears the airmass will remain capped during the day in thevicinity of the dryline, with storm development likely delayed untillate evening into the overnight per recent model guidance.  Verysteep 700-500 mb lapse rates, strong deep-layer shear magnitudes (50kt effective shear), and 2000-3000 J/kg MUCAPE will support a severerisk with any sustained storms.  Models vary between very isolatedcoverage and scattered storm coverage, especially over parts ofcentral into north TX.  Given consistency in some model guidance(e.g., HRRR model run to run, GFS, ECMWF) showing some convectivesignal, have opted to increase hail probabilities to level-2 SlightRisk overnight.  Large to very large hail is possible with thestronger storms (1 to 2.5 inches in diameter)....Louisiana/Mississippi...A remnant MCV will continue to move northeastward this afternoonacross the lower MS Valley and Mid-South.  Although deep-layer shearis expected to remain fairly weak, sufficient low-level shear shouldbe present to support some updraft organization and transientrotation with the stronger storms.  Cells movingnortheastward and inland over the central Gulf Coast may pose athreat for a brief tornado, as well as a localized risk for damaginggusts...Smith/Dean.. 03/29/2025

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SPC 2000Z Day 1 Outlook

Day 1 Convective Outlook  NWS Storm Prediction Center Norman OK0257 PM CDT Wed Apr 02 2025Valid 022000Z - 031200Z...THERE IS A HIGH RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON INTOEARLY TONIGHT FROM EASTERN ARKANSAS/NORTHWEST MISSISSIPPI TO THELOWER OH VALLEY......SUMMARY...A tornado outbreak is expected this afternoon into early tonightfrom parts of the lower Mississippi Valley into the Mid-South andlower Ohio Valley. Numerous tornadoes, along with multiple EF3+tornadoes, appear likely. In addition, tornadoes, significant severewind gusts, and large hail to very large hail will be possibleacross a broad area from north Texas northeastward to the southernGreat Lakes....Mid-South to the OH Valley through tonight...Convection is intensifying within a band from western AR intosouthern MO, and additional storm development is likely thisafternoon farther northeast into IL.  Multiple, embedded supercellsare developing within this band, and the threat for tornadoes, largehail and damaging winds will increase through the afternoon and intothe evening as the storms spread into a more favorable downstreamenvironment.  Warm sector supercell development appears to beunderway across southeast AR/northwest MS, and more developmentcould occur farther northeast into the lower OH Valley.  A special18z LZK special sounding revealed substantial moistening/ascent inthe 850-700 mb layer since 12z and additional weakening of the capfrom below is expected the remainder of the afternoon.  Continuedmoistening from the south and strong low-level shear through lateevening will support the potential for strong-intense (EF2-EF3+) andlong track tornadoes with any sustained warm sector supercells.Convection is still expected to evolve into a more extensive squallline late this afternoon into early tonight, with the potential toproduce widespread damaging winds of 65-85 mph into the OH Valley. Tornadoes, some strong, will be possible with embedded circulations,and especially with any discrete supercells ahead of the line thisevening into IN and vicinity.  The damaging-wind threat will persistacross much of OH before weakening late tonight across easternOH/western PA....North TX early Thursday...With amplification of the large-scale trough over the Southwest, thesurface boundary across central TX is expected to stall this eveningand return north/northwestward as a warm front late tonight inresponse to weak cyclogenesis and a strenthening warm advectionregime.  The pattern will become favorable for elevated supercellson the immediate cool side of the boundary, with an accompanyingthreat for very large hail (near 2.5 inches in diameter) andisolated wind damage from 06-12z...Thompson.. 04/02/2025.PREV DISCUSSION... /ISSUED 1126 AM CDT Wed Apr 02 2025/...OH/MS Valleys through tonight...In response to an ejecting midlevel trough and associated 110 kt 500mb jet streak, a surface cyclone will develop northeastward from IAto Lake Superior.  Severe storms are ongoing in a broken band fromwest central IL across MO into northwest AR/eastern OK, whichdemarcates the effective frontal zone and focus for additional stormdevelopment through the afternoon.  The warm sector in advance ofthese storms is characterized by boundary-layer dewpoints in thelow-mid 60s across IL/MO and near 70 F from the Ark-La-Tex into theArk-La-Miss.  Low-level moisture will continue to spread northwardthrough the day on 50-70 kt flow 1-2 km above ground level, andsurface heating in cloud breaks will boost MLCAPE into the 2000-3000J/kg range with only weak convective inhibition through theafternoon.  The northern extent of the surface warm sector(northeast IL across northern IN/northwest OH/southern Lower MI)will be modulated by ongoing convection.The primary jet streak/cyclone will be displaced northwest of theunstable warm sector, though flow will remain strong in the warmsector with long hodographs and substantial low-levelshear/hodograph curvature.  Convective mode is expected to besomewhat messy with embedded supercells within an increasinglyextensive band of storms through the afternoon/evening.  Convectiveinhibition will be sufficiently weak to support some potential for afew supercells ahead of the band in the open warm sector.  Thetornado threat will be maximized for the more discrete storms withinor ahead of the main band, where a few intense (EF3+) tornadoes willbe possible.  Otherwise, evolution into an extensive squall line isexpected with an accompanying threat for damaging winds (60-80 mph)and occasional large hail (1.5-2.5 inches in diameter - especiallywith persistent supercells).  Overnight, the northern portion of the squall line will eventuallymove east of the more unstable warm sector and weaken from OH intowestern PA.  The southern portion of the convective band is expectedto pivot gradually to a more WSW-ENE orientation favoring trainingconvection along and atop the conglomerate cold pool....North TX/southeast OK this evening through Thursday morning...In the wake of the ejecting IA-Lake Superior jet streak, midlevelflow will tend to amplify/back with time over TX, downstream of theamplifying large-scale trough over the Southwest.  This willcontribute to weak cyclogenesis across northwest TX along theresidual baroclinic zone, and a strengthening warm advection regimealong/north of the boundary tonight.  The open warm sector willlikely remain capped (per the warm elevated mixed layer observedthis morning over TX), but the environment will favor elevatedsupercells to the cool side of the boundary.  Very large hail inexcess of 2 inches in diameter and isolated severe gusts will be themain threats with these elevated storms overnight.

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SPC 1630Z Day 1 Outlook

Day 1 Convective Outlook  NWS Storm Prediction Center Norman OK1134 AM CDT Sat Mar 29 2025Valid 291630Z - 301200Z...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OFTHE CENTRAL AND SOUTHERN GREAT PLAINS INTO THE MIDDLE MISSISSIPPIVALLEY......SUMMARY...Scattered severe thunderstorms are possible across parts of thecentral/southern Plains into the mid Mississippi Valley, mainly thisevening through the overnight hours. This may include an organizedthunderstorm cluster across parts of Oklahoma into southeasternKansas and western Missouri capable of producing very large hail,damaging winds, and perhaps a couple of tornadoes....Central/Southern Plains into the Mid Mississippi Valley...Water-vapor imagery shows a lead disturbance moving northeastwardacross the central Great Plains towards the Upper Midwest, while anupstream disturbance moves from eastern AZ into the southern GreatPlains tonight.  The primary surface low over western KS thismorning is forecast to develop east-northeastward towards southernIA/northern MO by tonight.  An attendant cold front will sweepsouthward across parts of the central/southern Plains through theperiod, while a dryline mixes eastward over the southern High Plainsthis afternoon.Surface analysis shows lower 60s dewpoints streaming northward onsoutherly low-level flow this morning from north TX to the KS/OKborder.  A substantial cap will likely inhibit robust convectivedevelopment until late this afternoon or early evening, with thecold front/dryline intersection over western OK a potential locationfor convective initiation by 23-03Z as large-scale ascent with thetrailing shortwave trough overspreads the warm sector. Moderate to strong buoyancy will likely be present acrosswestern/northern OK and southern KS, with steep mid-level lapserates atop upper 50s to mid 60s surface dewpoints.  Forecastsoundings favor supercell development with activity that developssouth of the front across west-central OK.  Large to very large hail(potentially up to 1.5-2.5 inches in diameter) may accompany thesestorms early in their convective life cycle.  Despite increasingCINH during the evening, lower 60s dewpoints in place with 500-mbtemperatures around -15 deg C may aid the development of a tornadorisk from central into northeast OK as storms mature and eventuallygrow upscale.  Severe gusts will probably become more prevalent withtime as this cluster moves east-northeast into parts of northeast OKand eventually into MO later tonight, perhaps with the wind threatslowly diminishing late.  Farther south, a conditional severe threat exists south of the RedRiver from north TX southwestward into parts of the Concho Valley. It appears the airmass will remain capped during the day in thevicinity of the dryline, with storm development likely delayed untillate evening into the overnight per recent model guidance.  Verysteep 700-500 mb lapse rates, strong deep-layer shear magnitudes (50kt effective shear), and 2000-3000 J/kg MUCAPE will support a severerisk with any sustained storms.  Models vary between very isolatedcoverage and scattered storm coverage, especially over parts ofcentral into north TX.  Given consistency in some model guidance(e.g., HRRR model run to run, GFS, ECMWF) showing some convectivesignal, have opted to increase hail probabilities to level-2 SlightRisk overnight.  Large to very large hail is possible with thestronger storms (1 to 2.5 inches in diameter)....Louisiana/Mississippi...A remnant MCV will continue to move northeastward this afternoonacross the lower MS Valley and Mid-South.  Although deep-layer shearis expected to remain fairly weak, sufficient low-level shear shouldbe present to support some updraft organization and transientrotation with the stronger storms.  Cells movingnortheastward and inland over the central Gulf Coast may pose athreat for a brief tornado, as well as a localized risk for damaginggusts...Smith/Dean.. 03/29/2025

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