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SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0348 PM CDT Wed Oct 30 2024 Valid 011200Z - 071200Z Upper-level flow will become quasi-zonal by the end of this week. During the weekend, another strong upper-level trough is expected to dig southward along the West Coast. This feature will then slowly progress to the east into the Plains early next week. Upper-level ridging will build into the West Coast in the wake of the trough. At the surface, high pressure will then build into the Great Basin late this weekend into Tuesday. Thereafter, the upper-level pattern becomes less predictable, though model consensus suggests another trough will move into the West by the middle of next week. ...Northern Mid-Atlantic into Northeast... The cold front expected to pass on Friday appears as though it will not produce much rainfall. A dry airmass behind the front will lead to falling RH values during the afternoon. The surface pressure gradient will be undergoing a slow weakening trend through the day and mixing depths will not be overly high to mix down stronger winds aloft. At least locally elevated conditions are possible and trends in wind speeds will have to be monitored as fuels remain quite dry. ...Southern California... Trends in model guidance have shown the track of the next strong upper-level trough to be farther north than previous days. This trend is noted in both the ECMWF and GFS. This would suggest overall less precipitation potential. That said, offshore winds will increase Sunday night into Tuesday morning which will also include some upper-level wind support. Model trends will continue to be monitored, but current fuel data suggest generally unperceptive fuels and there is still some uncertainty in the stability of these latest model trends. ..Wendt.. 10/30/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0348 PM CDT Wed Oct 30 2024 Valid 011200Z - 071200Z Upper-level flow will become quasi-zonal by the end of this week. During the weekend, another strong upper-level trough is expected to dig southward along the West Coast. This feature will then slowly progress to the east into the Plains early next week. Upper-level ridging will build into the West Coast in the wake of the trough. At the surface, high pressure will then build into the Great Basin late this weekend into Tuesday. Thereafter, the upper-level pattern becomes less predictable, though model consensus suggests another trough will move into the West by the middle of next week. ...Northern Mid-Atlantic into Northeast... The cold front expected to pass on Friday appears as though it will not produce much rainfall. A dry airmass behind the front will lead to falling RH values during the afternoon. The surface pressure gradient will be undergoing a slow weakening trend through the day and mixing depths will not be overly high to mix down stronger winds aloft. At least locally elevated conditions are possible and trends in wind speeds will have to be monitored as fuels remain quite dry. ...Southern California... Trends in model guidance have shown the track of the next strong upper-level trough to be farther north than previous days. This trend is noted in both the ECMWF and GFS. This would suggest overall less precipitation potential. That said, offshore winds will increase Sunday night into Tuesday morning which will also include some upper-level wind support. Model trends will continue to be monitored, but current fuel data suggest generally unperceptive fuels and there is still some uncertainty in the stability of these latest model trends. ..Wendt.. 10/30/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0348 PM CDT Wed Oct 30 2024 Valid 011200Z - 071200Z Upper-level flow will become quasi-zonal by the end of this week. During the weekend, another strong upper-level trough is expected to dig southward along the West Coast. This feature will then slowly progress to the east into the Plains early next week. Upper-level ridging will build into the West Coast in the wake of the trough. At the surface, high pressure will then build into the Great Basin late this weekend into Tuesday. Thereafter, the upper-level pattern becomes less predictable, though model consensus suggests another trough will move into the West by the middle of next week. ...Northern Mid-Atlantic into Northeast... The cold front expected to pass on Friday appears as though it will not produce much rainfall. A dry airmass behind the front will lead to falling RH values during the afternoon. The surface pressure gradient will be undergoing a slow weakening trend through the day and mixing depths will not be overly high to mix down stronger winds aloft. At least locally elevated conditions are possible and trends in wind speeds will have to be monitored as fuels remain quite dry. ...Southern California... Trends in model guidance have shown the track of the next strong upper-level trough to be farther north than previous days. This trend is noted in both the ECMWF and GFS. This would suggest overall less precipitation potential. That said, offshore winds will increase Sunday night into Tuesday morning which will also include some upper-level wind support. Model trends will continue to be monitored, but current fuel data suggest generally unperceptive fuels and there is still some uncertainty in the stability of these latest model trends. ..Wendt.. 10/30/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0348 PM CDT Wed Oct 30 2024 Valid 011200Z - 071200Z Upper-level flow will become quasi-zonal by the end of this week. During the weekend, another strong upper-level trough is expected to dig southward along the West Coast. This feature will then slowly progress to the east into the Plains early next week. Upper-level ridging will build into the West Coast in the wake of the trough. At the surface, high pressure will then build into the Great Basin late this weekend into Tuesday. Thereafter, the upper-level pattern becomes less predictable, though model consensus suggests another trough will move into the West by the middle of next week. ...Northern Mid-Atlantic into Northeast... The cold front expected to pass on Friday appears as though it will not produce much rainfall. A dry airmass behind the front will lead to falling RH values during the afternoon. The surface pressure gradient will be undergoing a slow weakening trend through the day and mixing depths will not be overly high to mix down stronger winds aloft. At least locally elevated conditions are possible and trends in wind speeds will have to be monitored as fuels remain quite dry. ...Southern California... Trends in model guidance have shown the track of the next strong upper-level trough to be farther north than previous days. This trend is noted in both the ECMWF and GFS. This would suggest overall less precipitation potential. That said, offshore winds will increase Sunday night into Tuesday morning which will also include some upper-level wind support. Model trends will continue to be monitored, but current fuel data suggest generally unperceptive fuels and there is still some uncertainty in the stability of these latest model trends. ..Wendt.. 10/30/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0348 PM CDT Wed Oct 30 2024 Valid 011200Z - 071200Z Upper-level flow will become quasi-zonal by the end of this week. During the weekend, another strong upper-level trough is expected to dig southward along the West Coast. This feature will then slowly progress to the east into the Plains early next week. Upper-level ridging will build into the West Coast in the wake of the trough. At the surface, high pressure will then build into the Great Basin late this weekend into Tuesday. Thereafter, the upper-level pattern becomes less predictable, though model consensus suggests another trough will move into the West by the middle of next week. ...Northern Mid-Atlantic into Northeast... The cold front expected to pass on Friday appears as though it will not produce much rainfall. A dry airmass behind the front will lead to falling RH values during the afternoon. The surface pressure gradient will be undergoing a slow weakening trend through the day and mixing depths will not be overly high to mix down stronger winds aloft. At least locally elevated conditions are possible and trends in wind speeds will have to be monitored as fuels remain quite dry. ...Southern California... Trends in model guidance have shown the track of the next strong upper-level trough to be farther north than previous days. This trend is noted in both the ECMWF and GFS. This would suggest overall less precipitation potential. That said, offshore winds will increase Sunday night into Tuesday morning which will also include some upper-level wind support. Model trends will continue to be monitored, but current fuel data suggest generally unperceptive fuels and there is still some uncertainty in the stability of these latest model trends. ..Wendt.. 10/30/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0348 PM CDT Wed Oct 30 2024 Valid 011200Z - 071200Z Upper-level flow will become quasi-zonal by the end of this week. During the weekend, another strong upper-level trough is expected to dig southward along the West Coast. This feature will then slowly progress to the east into the Plains early next week. Upper-level ridging will build into the West Coast in the wake of the trough. At the surface, high pressure will then build into the Great Basin late this weekend into Tuesday. Thereafter, the upper-level pattern becomes less predictable, though model consensus suggests another trough will move into the West by the middle of next week. ...Northern Mid-Atlantic into Northeast... The cold front expected to pass on Friday appears as though it will not produce much rainfall. A dry airmass behind the front will lead to falling RH values during the afternoon. The surface pressure gradient will be undergoing a slow weakening trend through the day and mixing depths will not be overly high to mix down stronger winds aloft. At least locally elevated conditions are possible and trends in wind speeds will have to be monitored as fuels remain quite dry. ...Southern California... Trends in model guidance have shown the track of the next strong upper-level trough to be farther north than previous days. This trend is noted in both the ECMWF and GFS. This would suggest overall less precipitation potential. That said, offshore winds will increase Sunday night into Tuesday morning which will also include some upper-level wind support. Model trends will continue to be monitored, but current fuel data suggest generally unperceptive fuels and there is still some uncertainty in the stability of these latest model trends. ..Wendt.. 10/30/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0348 PM CDT Wed Oct 30 2024 Valid 011200Z - 071200Z Upper-level flow will become quasi-zonal by the end of this week. During the weekend, another strong upper-level trough is expected to dig southward along the West Coast. This feature will then slowly progress to the east into the Plains early next week. Upper-level ridging will build into the West Coast in the wake of the trough. At the surface, high pressure will then build into the Great Basin late this weekend into Tuesday. Thereafter, the upper-level pattern becomes less predictable, though model consensus suggests another trough will move into the West by the middle of next week. ...Northern Mid-Atlantic into Northeast... The cold front expected to pass on Friday appears as though it will not produce much rainfall. A dry airmass behind the front will lead to falling RH values during the afternoon. The surface pressure gradient will be undergoing a slow weakening trend through the day and mixing depths will not be overly high to mix down stronger winds aloft. At least locally elevated conditions are possible and trends in wind speeds will have to be monitored as fuels remain quite dry. ...Southern California... Trends in model guidance have shown the track of the next strong upper-level trough to be farther north than previous days. This trend is noted in both the ECMWF and GFS. This would suggest overall less precipitation potential. That said, offshore winds will increase Sunday night into Tuesday morning which will also include some upper-level wind support. Model trends will continue to be monitored, but current fuel data suggest generally unperceptive fuels and there is still some uncertainty in the stability of these latest model trends. ..Wendt.. 10/30/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0348 PM CDT Wed Oct 30 2024 Valid 011200Z - 071200Z Upper-level flow will become quasi-zonal by the end of this week. During the weekend, another strong upper-level trough is expected to dig southward along the West Coast. This feature will then slowly progress to the east into the Plains early next week. Upper-level ridging will build into the West Coast in the wake of the trough. At the surface, high pressure will then build into the Great Basin late this weekend into Tuesday. Thereafter, the upper-level pattern becomes less predictable, though model consensus suggests another trough will move into the West by the middle of next week. ...Northern Mid-Atlantic into Northeast... The cold front expected to pass on Friday appears as though it will not produce much rainfall. A dry airmass behind the front will lead to falling RH values during the afternoon. The surface pressure gradient will be undergoing a slow weakening trend through the day and mixing depths will not be overly high to mix down stronger winds aloft. At least locally elevated conditions are possible and trends in wind speeds will have to be monitored as fuels remain quite dry. ...Southern California... Trends in model guidance have shown the track of the next strong upper-level trough to be farther north than previous days. This trend is noted in both the ECMWF and GFS. This would suggest overall less precipitation potential. That said, offshore winds will increase Sunday night into Tuesday morning which will also include some upper-level wind support. Model trends will continue to be monitored, but current fuel data suggest generally unperceptive fuels and there is still some uncertainty in the stability of these latest model trends. ..Wendt.. 10/30/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0348 PM CDT Wed Oct 30 2024 Valid 011200Z - 071200Z Upper-level flow will become quasi-zonal by the end of this week. During the weekend, another strong upper-level trough is expected to dig southward along the West Coast. This feature will then slowly progress to the east into the Plains early next week. Upper-level ridging will build into the West Coast in the wake of the trough. At the surface, high pressure will then build into the Great Basin late this weekend into Tuesday. Thereafter, the upper-level pattern becomes less predictable, though model consensus suggests another trough will move into the West by the middle of next week. ...Northern Mid-Atlantic into Northeast... The cold front expected to pass on Friday appears as though it will not produce much rainfall. A dry airmass behind the front will lead to falling RH values during the afternoon. The surface pressure gradient will be undergoing a slow weakening trend through the day and mixing depths will not be overly high to mix down stronger winds aloft. At least locally elevated conditions are possible and trends in wind speeds will have to be monitored as fuels remain quite dry. ...Southern California... Trends in model guidance have shown the track of the next strong upper-level trough to be farther north than previous days. This trend is noted in both the ECMWF and GFS. This would suggest overall less precipitation potential. That said, offshore winds will increase Sunday night into Tuesday morning which will also include some upper-level wind support. Model trends will continue to be monitored, but current fuel data suggest generally unperceptive fuels and there is still some uncertainty in the stability of these latest model trends. ..Wendt.. 10/30/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0348 PM CDT Wed Oct 30 2024 Valid 011200Z - 071200Z Upper-level flow will become quasi-zonal by the end of this week. During the weekend, another strong upper-level trough is expected to dig southward along the West Coast. This feature will then slowly progress to the east into the Plains early next week. Upper-level ridging will build into the West Coast in the wake of the trough. At the surface, high pressure will then build into the Great Basin late this weekend into Tuesday. Thereafter, the upper-level pattern becomes less predictable, though model consensus suggests another trough will move into the West by the middle of next week. ...Northern Mid-Atlantic into Northeast... The cold front expected to pass on Friday appears as though it will not produce much rainfall. A dry airmass behind the front will lead to falling RH values during the afternoon. The surface pressure gradient will be undergoing a slow weakening trend through the day and mixing depths will not be overly high to mix down stronger winds aloft. At least locally elevated conditions are possible and trends in wind speeds will have to be monitored as fuels remain quite dry. ...Southern California... Trends in model guidance have shown the track of the next strong upper-level trough to be farther north than previous days. This trend is noted in both the ECMWF and GFS. This would suggest overall less precipitation potential. That said, offshore winds will increase Sunday night into Tuesday morning which will also include some upper-level wind support. Model trends will continue to be monitored, but current fuel data suggest generally unperceptive fuels and there is still some uncertainty in the stability of these latest model trends. ..Wendt.. 10/30/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

WW 0694 Status Updates
STATUS REPORT ON WW 694 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 WSW CSM TO 25 NNW CSM TO 40 SSW AVK TO 20 WSW AVK TO 20 SW P28 TO 30 SW HUT TO 15 SSE SLN. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 2166 ..BENTLEY..10/30/24 ATTN...WFO...DDC...ICT...OUN... STATUS REPORT FOR WT 694 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS KSC007-015-017-035-077-079-095-115-155-173-191-302140- KS . KANSAS COUNTIES INCLUDED ARE BARBER BUTLER CHASE COWLEY HARPER HARVEY KINGMAN MARION RENO SEDGWICK SUMNER OKC003-011-015-017-027-039-043-047-051-053-071-073-083-087-093- 103-109-119-149-151-302140- OK . OKLAHOMA COUNTIES INCLUDED ARE ALFALFA BLAINE CADDO CANADIAN CLEVELAND CUSTER DEWEY GARFIELD GRADY GRANT KAY KINGFISHER LOGAN MCCLAIN MAJOR Read more

Hackensack’s Office of Emergency Management issued an “Extreme Wildfire Risk” which bans all outdoor fires, except those in propane, gas or electric stoves. Wood and charcoal fires and fireworks were prohibited. The area was very dry and has gone 25 days without rain. TAPinto Hackensack (N.J.), Oct 30, 2024

WW 0693 Status Updates
STATUS REPORT ON WW 693 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 WNW FLV TO 35 SW LWD TO 25 SSW DSM TO 35 SSE FOD. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 2165 ..MOORE..10/30/24 ATTN...WFO...DMX...OAX...EAX... STATUS REPORT FOR WS 693 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS IAC007-039-051-053-099-117-123-125-127-135-153-157-171-179-181- 185-302140- IA . IOWA COUNTIES INCLUDED ARE APPANOOSE CLARKE DAVIS DECATUR JASPER LUCAS MAHASKA MARION MARSHALL MONROE POLK POWESHIEK TAMA WAPELLO WARREN WAYNE MOC001-021-061-063-079-081-129-171-197-211-302140- MO . MISSOURI COUNTIES INCLUDED ARE ADAIR BUCHANAN DAVIESS DEKALB GRUNDY HARRISON MERCER PUTNAM SCHUYLER SULLIVAN Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Wed Oct 30 2024 Valid 302000Z - 311200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS NORTHERN/CENTRAL OKLAHOMA INTO CENTRAL/EASTERN KANSAS AND WESTERN MISSOURI... ...SUMMARY... Severe thunderstorms capable of producing scattered large hail, numerous damaging wind gusts, and a few tornadoes are expected today into tonight across the middle Missouri Valley and central/southern Plains, including parts of eastern Kansas/Oklahoma into Missouri and vicinity. A strong tornado or two is possible across south-central/southeastern Kansas into central Oklahoma. ...20z Update... The Enhanced Risk was expanded further southward through the Oklahoma City metro with this update. The Slight Risk was also expanded further west and southward. Recent trends in satellite and radar have shown cell development further south and west along the dryline than previously forecast. The environment across central Oklahoma is favorable for maintenance of supercells, with daytime heating yielding MLCAPE around 1500 J/kg and shear around 40 kts progged to increase with the increasing low level jet this afternoon/evening. Boundary parallel shear and overtaking of the dryline by the cold front will lead to a transition to more linear structure around sunset. However, deep layer shear profiles will continue to support embedded supercell structures after dark with the potential for tornadoes, some strong, to continue through the evening. Large hail will also be a concern late afternoon/early evening while discrete mode is maintained. Tornado probabilities were adjusted across northeastern Kansas to account for progression of the cold front and earlier convective activity. See previous discussion for more information. ..Thornton/Gleason.. 10/30/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Wed Oct 30 2024/ ...Southern/Central Plains into the Mid Missouri Valley... The lead portion of an upper trough centered over the Rockies and Four Corners will eject northeastward over the central Plains today. A related surface low will likewise develop northeastward along a cold front from the southern High Plains to IA by this evening. A dryline extending southward from this low will mix eastward across western OK and west TX through late this afternoon before stalling. Robust low-level warm/moist advection will continue today across the southern/central Plains along and south/east of the cold front and dryline. Generally elevated thunderstorms have developed this morning across parts of central KS, as large-scale ascent preceding the ejecting upper trough has begun to overspread the central Plains. This activity should tend to remain just to the cool side of the front through the early afternoon. But, this convection may pose some threat for severe hail given sufficient MUCAPE with steepening mid-level lapse rates in the presence of strong deep-layer shear. There is also some chance it eventually becomes surface based later this afternoon across northeast KS. Otherwise, continued filtered daytime heating of the moistening warm sector should support around 500-1500 J/kg of MLCAPE by late afternoon from southern IA into eastern KS/western MO, and locally stronger to around 2000 J/kg in north-central OK. Current expectations are for surface-based thunderstorms to initiate by 20-22Z across central/eastern KS and north-central/northwest OK, in close proximity to the surface low and front/dryline intersection. Rather strong (50-80 kt) southwesterly mid-level flow will overlie this region this afternoon/evening, along with enhanced south-southwesterly flow in the 850-700 mb layer. Related deep-layer shear around 45-60 kt will easily support supercells and associated threat for scattered hail initially. Isolated very large hail may occur from south-central KS into north-central OK with any sustained supercell given the rather favorable overlap of moderate instability with steepened mid-level lapse rates and strong deep-layer shear. With time this evening, upscale growth into a QLCS with greater threat for severe/damaging winds is anticipated. This severe/damaging wind threat should continue tonight as the line spreads eastward across IA/MO, before eventually becoming more isolated/diminishing with eastward extent into the mid MS Valley. The tornado potential should also increase late this afternoon and evening, as a southerly low-level jet and related 0-1 km SRH strengthens rapidly through 23-04Z. The potential for sustained supercells in central/eastern KS and north-central OK remains somewhat unclear, but any semi-discrete activity will pose a threat for tornadoes, a couple of which could be strong given the favorable low-level shear and hodograph curvature. Embedded mesovorticies within the QLCS will also be possible. Based on latest guidance and observational trends, severe probabilities have been expanded westward some across KS/OK, especially in the vicinity of the expected front/dryline intersection. The Enhanced Risk has also been expanded slightly eastward in western MO to account for scattered to numerous severe wind gusts with the QLCS this evening. Convective initiation may be delayed until around 00Z or later across central/eastern OK. But, potential for discrete supercells may be a bit better across this region given the dryline as the initiating boundary, and somewhat less large-scale ascent with southward extent away from the cold front. Any convection that can develop and be sustained will likely be supercellular for at least a couple of hours this evening, before upscale growth eventually occurs along the cold front. A threat for large hail and tornadoes will exist with any supercell, before the damaging wind threat increases as the convective mode becomes more linear. ...Southeast Texas... There is some potential that a few stronger/potentially rotating thunderstorms could materialize today across the region within a very moist and confluent low-level flow regime. This would be as low-level lapse rates diurnally steepen coincident with a moderate degree of low-level hodograph length and curvature. Modest-strength winds above 2km AGL should limit the sustainability and intensity for any showers/thunderstorms that may exhibit rotating characteristics, and the overall severe potential should tend to remain limited. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Wed Oct 30 2024 Valid 302000Z - 311200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS NORTHERN/CENTRAL OKLAHOMA INTO CENTRAL/EASTERN KANSAS AND WESTERN MISSOURI... ...SUMMARY... Severe thunderstorms capable of producing scattered large hail, numerous damaging wind gusts, and a few tornadoes are expected today into tonight across the middle Missouri Valley and central/southern Plains, including parts of eastern Kansas/Oklahoma into Missouri and vicinity. A strong tornado or two is possible across south-central/southeastern Kansas into central Oklahoma. ...20z Update... The Enhanced Risk was expanded further southward through the Oklahoma City metro with this update. The Slight Risk was also expanded further west and southward. Recent trends in satellite and radar have shown cell development further south and west along the dryline than previously forecast. The environment across central Oklahoma is favorable for maintenance of supercells, with daytime heating yielding MLCAPE around 1500 J/kg and shear around 40 kts progged to increase with the increasing low level jet this afternoon/evening. Boundary parallel shear and overtaking of the dryline by the cold front will lead to a transition to more linear structure around sunset. However, deep layer shear profiles will continue to support embedded supercell structures after dark with the potential for tornadoes, some strong, to continue through the evening. Large hail will also be a concern late afternoon/early evening while discrete mode is maintained. Tornado probabilities were adjusted across northeastern Kansas to account for progression of the cold front and earlier convective activity. See previous discussion for more information. ..Thornton/Gleason.. 10/30/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Wed Oct 30 2024/ ...Southern/Central Plains into the Mid Missouri Valley... The lead portion of an upper trough centered over the Rockies and Four Corners will eject northeastward over the central Plains today. A related surface low will likewise develop northeastward along a cold front from the southern High Plains to IA by this evening. A dryline extending southward from this low will mix eastward across western OK and west TX through late this afternoon before stalling. Robust low-level warm/moist advection will continue today across the southern/central Plains along and south/east of the cold front and dryline. Generally elevated thunderstorms have developed this morning across parts of central KS, as large-scale ascent preceding the ejecting upper trough has begun to overspread the central Plains. This activity should tend to remain just to the cool side of the front through the early afternoon. But, this convection may pose some threat for severe hail given sufficient MUCAPE with steepening mid-level lapse rates in the presence of strong deep-layer shear. There is also some chance it eventually becomes surface based later this afternoon across northeast KS. Otherwise, continued filtered daytime heating of the moistening warm sector should support around 500-1500 J/kg of MLCAPE by late afternoon from southern IA into eastern KS/western MO, and locally stronger to around 2000 J/kg in north-central OK. Current expectations are for surface-based thunderstorms to initiate by 20-22Z across central/eastern KS and north-central/northwest OK, in close proximity to the surface low and front/dryline intersection. Rather strong (50-80 kt) southwesterly mid-level flow will overlie this region this afternoon/evening, along with enhanced south-southwesterly flow in the 850-700 mb layer. Related deep-layer shear around 45-60 kt will easily support supercells and associated threat for scattered hail initially. Isolated very large hail may occur from south-central KS into north-central OK with any sustained supercell given the rather favorable overlap of moderate instability with steepened mid-level lapse rates and strong deep-layer shear. With time this evening, upscale growth into a QLCS with greater threat for severe/damaging winds is anticipated. This severe/damaging wind threat should continue tonight as the line spreads eastward across IA/MO, before eventually becoming more isolated/diminishing with eastward extent into the mid MS Valley. The tornado potential should also increase late this afternoon and evening, as a southerly low-level jet and related 0-1 km SRH strengthens rapidly through 23-04Z. The potential for sustained supercells in central/eastern KS and north-central OK remains somewhat unclear, but any semi-discrete activity will pose a threat for tornadoes, a couple of which could be strong given the favorable low-level shear and hodograph curvature. Embedded mesovorticies within the QLCS will also be possible. Based on latest guidance and observational trends, severe probabilities have been expanded westward some across KS/OK, especially in the vicinity of the expected front/dryline intersection. The Enhanced Risk has also been expanded slightly eastward in western MO to account for scattered to numerous severe wind gusts with the QLCS this evening. Convective initiation may be delayed until around 00Z or later across central/eastern OK. But, potential for discrete supercells may be a bit better across this region given the dryline as the initiating boundary, and somewhat less large-scale ascent with southward extent away from the cold front. Any convection that can develop and be sustained will likely be supercellular for at least a couple of hours this evening, before upscale growth eventually occurs along the cold front. A threat for large hail and tornadoes will exist with any supercell, before the damaging wind threat increases as the convective mode becomes more linear. ...Southeast Texas... There is some potential that a few stronger/potentially rotating thunderstorms could materialize today across the region within a very moist and confluent low-level flow regime. This would be as low-level lapse rates diurnally steepen coincident with a moderate degree of low-level hodograph length and curvature. Modest-strength winds above 2km AGL should limit the sustainability and intensity for any showers/thunderstorms that may exhibit rotating characteristics, and the overall severe potential should tend to remain limited. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Wed Oct 30 2024 Valid 302000Z - 311200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS NORTHERN/CENTRAL OKLAHOMA INTO CENTRAL/EASTERN KANSAS AND WESTERN MISSOURI... ...SUMMARY... Severe thunderstorms capable of producing scattered large hail, numerous damaging wind gusts, and a few tornadoes are expected today into tonight across the middle Missouri Valley and central/southern Plains, including parts of eastern Kansas/Oklahoma into Missouri and vicinity. A strong tornado or two is possible across south-central/southeastern Kansas into central Oklahoma. ...20z Update... The Enhanced Risk was expanded further southward through the Oklahoma City metro with this update. The Slight Risk was also expanded further west and southward. Recent trends in satellite and radar have shown cell development further south and west along the dryline than previously forecast. The environment across central Oklahoma is favorable for maintenance of supercells, with daytime heating yielding MLCAPE around 1500 J/kg and shear around 40 kts progged to increase with the increasing low level jet this afternoon/evening. Boundary parallel shear and overtaking of the dryline by the cold front will lead to a transition to more linear structure around sunset. However, deep layer shear profiles will continue to support embedded supercell structures after dark with the potential for tornadoes, some strong, to continue through the evening. Large hail will also be a concern late afternoon/early evening while discrete mode is maintained. Tornado probabilities were adjusted across northeastern Kansas to account for progression of the cold front and earlier convective activity. See previous discussion for more information. ..Thornton/Gleason.. 10/30/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Wed Oct 30 2024/ ...Southern/Central Plains into the Mid Missouri Valley... The lead portion of an upper trough centered over the Rockies and Four Corners will eject northeastward over the central Plains today. A related surface low will likewise develop northeastward along a cold front from the southern High Plains to IA by this evening. A dryline extending southward from this low will mix eastward across western OK and west TX through late this afternoon before stalling. Robust low-level warm/moist advection will continue today across the southern/central Plains along and south/east of the cold front and dryline. Generally elevated thunderstorms have developed this morning across parts of central KS, as large-scale ascent preceding the ejecting upper trough has begun to overspread the central Plains. This activity should tend to remain just to the cool side of the front through the early afternoon. But, this convection may pose some threat for severe hail given sufficient MUCAPE with steepening mid-level lapse rates in the presence of strong deep-layer shear. There is also some chance it eventually becomes surface based later this afternoon across northeast KS. Otherwise, continued filtered daytime heating of the moistening warm sector should support around 500-1500 J/kg of MLCAPE by late afternoon from southern IA into eastern KS/western MO, and locally stronger to around 2000 J/kg in north-central OK. Current expectations are for surface-based thunderstorms to initiate by 20-22Z across central/eastern KS and north-central/northwest OK, in close proximity to the surface low and front/dryline intersection. Rather strong (50-80 kt) southwesterly mid-level flow will overlie this region this afternoon/evening, along with enhanced south-southwesterly flow in the 850-700 mb layer. Related deep-layer shear around 45-60 kt will easily support supercells and associated threat for scattered hail initially. Isolated very large hail may occur from south-central KS into north-central OK with any sustained supercell given the rather favorable overlap of moderate instability with steepened mid-level lapse rates and strong deep-layer shear. With time this evening, upscale growth into a QLCS with greater threat for severe/damaging winds is anticipated. This severe/damaging wind threat should continue tonight as the line spreads eastward across IA/MO, before eventually becoming more isolated/diminishing with eastward extent into the mid MS Valley. The tornado potential should also increase late this afternoon and evening, as a southerly low-level jet and related 0-1 km SRH strengthens rapidly through 23-04Z. The potential for sustained supercells in central/eastern KS and north-central OK remains somewhat unclear, but any semi-discrete activity will pose a threat for tornadoes, a couple of which could be strong given the favorable low-level shear and hodograph curvature. Embedded mesovorticies within the QLCS will also be possible. Based on latest guidance and observational trends, severe probabilities have been expanded westward some across KS/OK, especially in the vicinity of the expected front/dryline intersection. The Enhanced Risk has also been expanded slightly eastward in western MO to account for scattered to numerous severe wind gusts with the QLCS this evening. Convective initiation may be delayed until around 00Z or later across central/eastern OK. But, potential for discrete supercells may be a bit better across this region given the dryline as the initiating boundary, and somewhat less large-scale ascent with southward extent away from the cold front. Any convection that can develop and be sustained will likely be supercellular for at least a couple of hours this evening, before upscale growth eventually occurs along the cold front. A threat for large hail and tornadoes will exist with any supercell, before the damaging wind threat increases as the convective mode becomes more linear. ...Southeast Texas... There is some potential that a few stronger/potentially rotating thunderstorms could materialize today across the region within a very moist and confluent low-level flow regime. This would be as low-level lapse rates diurnally steepen coincident with a moderate degree of low-level hodograph length and curvature. Modest-strength winds above 2km AGL should limit the sustainability and intensity for any showers/thunderstorms that may exhibit rotating characteristics, and the overall severe potential should tend to remain limited. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Wed Oct 30 2024 Valid 302000Z - 311200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS NORTHERN/CENTRAL OKLAHOMA INTO CENTRAL/EASTERN KANSAS AND WESTERN MISSOURI... ...SUMMARY... Severe thunderstorms capable of producing scattered large hail, numerous damaging wind gusts, and a few tornadoes are expected today into tonight across the middle Missouri Valley and central/southern Plains, including parts of eastern Kansas/Oklahoma into Missouri and vicinity. A strong tornado or two is possible across south-central/southeastern Kansas into central Oklahoma. ...20z Update... The Enhanced Risk was expanded further southward through the Oklahoma City metro with this update. The Slight Risk was also expanded further west and southward. Recent trends in satellite and radar have shown cell development further south and west along the dryline than previously forecast. The environment across central Oklahoma is favorable for maintenance of supercells, with daytime heating yielding MLCAPE around 1500 J/kg and shear around 40 kts progged to increase with the increasing low level jet this afternoon/evening. Boundary parallel shear and overtaking of the dryline by the cold front will lead to a transition to more linear structure around sunset. However, deep layer shear profiles will continue to support embedded supercell structures after dark with the potential for tornadoes, some strong, to continue through the evening. Large hail will also be a concern late afternoon/early evening while discrete mode is maintained. Tornado probabilities were adjusted across northeastern Kansas to account for progression of the cold front and earlier convective activity. See previous discussion for more information. ..Thornton/Gleason.. 10/30/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Wed Oct 30 2024/ ...Southern/Central Plains into the Mid Missouri Valley... The lead portion of an upper trough centered over the Rockies and Four Corners will eject northeastward over the central Plains today. A related surface low will likewise develop northeastward along a cold front from the southern High Plains to IA by this evening. A dryline extending southward from this low will mix eastward across western OK and west TX through late this afternoon before stalling. Robust low-level warm/moist advection will continue today across the southern/central Plains along and south/east of the cold front and dryline. Generally elevated thunderstorms have developed this morning across parts of central KS, as large-scale ascent preceding the ejecting upper trough has begun to overspread the central Plains. This activity should tend to remain just to the cool side of the front through the early afternoon. But, this convection may pose some threat for severe hail given sufficient MUCAPE with steepening mid-level lapse rates in the presence of strong deep-layer shear. There is also some chance it eventually becomes surface based later this afternoon across northeast KS. Otherwise, continued filtered daytime heating of the moistening warm sector should support around 500-1500 J/kg of MLCAPE by late afternoon from southern IA into eastern KS/western MO, and locally stronger to around 2000 J/kg in north-central OK. Current expectations are for surface-based thunderstorms to initiate by 20-22Z across central/eastern KS and north-central/northwest OK, in close proximity to the surface low and front/dryline intersection. Rather strong (50-80 kt) southwesterly mid-level flow will overlie this region this afternoon/evening, along with enhanced south-southwesterly flow in the 850-700 mb layer. Related deep-layer shear around 45-60 kt will easily support supercells and associated threat for scattered hail initially. Isolated very large hail may occur from south-central KS into north-central OK with any sustained supercell given the rather favorable overlap of moderate instability with steepened mid-level lapse rates and strong deep-layer shear. With time this evening, upscale growth into a QLCS with greater threat for severe/damaging winds is anticipated. This severe/damaging wind threat should continue tonight as the line spreads eastward across IA/MO, before eventually becoming more isolated/diminishing with eastward extent into the mid MS Valley. The tornado potential should also increase late this afternoon and evening, as a southerly low-level jet and related 0-1 km SRH strengthens rapidly through 23-04Z. The potential for sustained supercells in central/eastern KS and north-central OK remains somewhat unclear, but any semi-discrete activity will pose a threat for tornadoes, a couple of which could be strong given the favorable low-level shear and hodograph curvature. Embedded mesovorticies within the QLCS will also be possible. Based on latest guidance and observational trends, severe probabilities have been expanded westward some across KS/OK, especially in the vicinity of the expected front/dryline intersection. The Enhanced Risk has also been expanded slightly eastward in western MO to account for scattered to numerous severe wind gusts with the QLCS this evening. Convective initiation may be delayed until around 00Z or later across central/eastern OK. But, potential for discrete supercells may be a bit better across this region given the dryline as the initiating boundary, and somewhat less large-scale ascent with southward extent away from the cold front. Any convection that can develop and be sustained will likely be supercellular for at least a couple of hours this evening, before upscale growth eventually occurs along the cold front. A threat for large hail and tornadoes will exist with any supercell, before the damaging wind threat increases as the convective mode becomes more linear. ...Southeast Texas... There is some potential that a few stronger/potentially rotating thunderstorms could materialize today across the region within a very moist and confluent low-level flow regime. This would be as low-level lapse rates diurnally steepen coincident with a moderate degree of low-level hodograph length and curvature. Modest-strength winds above 2km AGL should limit the sustainability and intensity for any showers/thunderstorms that may exhibit rotating characteristics, and the overall severe potential should tend to remain limited. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Wed Oct 30 2024 Valid 302000Z - 311200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS NORTHERN/CENTRAL OKLAHOMA INTO CENTRAL/EASTERN KANSAS AND WESTERN MISSOURI... ...SUMMARY... Severe thunderstorms capable of producing scattered large hail, numerous damaging wind gusts, and a few tornadoes are expected today into tonight across the middle Missouri Valley and central/southern Plains, including parts of eastern Kansas/Oklahoma into Missouri and vicinity. A strong tornado or two is possible across south-central/southeastern Kansas into central Oklahoma. ...20z Update... The Enhanced Risk was expanded further southward through the Oklahoma City metro with this update. The Slight Risk was also expanded further west and southward. Recent trends in satellite and radar have shown cell development further south and west along the dryline than previously forecast. The environment across central Oklahoma is favorable for maintenance of supercells, with daytime heating yielding MLCAPE around 1500 J/kg and shear around 40 kts progged to increase with the increasing low level jet this afternoon/evening. Boundary parallel shear and overtaking of the dryline by the cold front will lead to a transition to more linear structure around sunset. However, deep layer shear profiles will continue to support embedded supercell structures after dark with the potential for tornadoes, some strong, to continue through the evening. Large hail will also be a concern late afternoon/early evening while discrete mode is maintained. Tornado probabilities were adjusted across northeastern Kansas to account for progression of the cold front and earlier convective activity. See previous discussion for more information. ..Thornton/Gleason.. 10/30/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Wed Oct 30 2024/ ...Southern/Central Plains into the Mid Missouri Valley... The lead portion of an upper trough centered over the Rockies and Four Corners will eject northeastward over the central Plains today. A related surface low will likewise develop northeastward along a cold front from the southern High Plains to IA by this evening. A dryline extending southward from this low will mix eastward across western OK and west TX through late this afternoon before stalling. Robust low-level warm/moist advection will continue today across the southern/central Plains along and south/east of the cold front and dryline. Generally elevated thunderstorms have developed this morning across parts of central KS, as large-scale ascent preceding the ejecting upper trough has begun to overspread the central Plains. This activity should tend to remain just to the cool side of the front through the early afternoon. But, this convection may pose some threat for severe hail given sufficient MUCAPE with steepening mid-level lapse rates in the presence of strong deep-layer shear. There is also some chance it eventually becomes surface based later this afternoon across northeast KS. Otherwise, continued filtered daytime heating of the moistening warm sector should support around 500-1500 J/kg of MLCAPE by late afternoon from southern IA into eastern KS/western MO, and locally stronger to around 2000 J/kg in north-central OK. Current expectations are for surface-based thunderstorms to initiate by 20-22Z across central/eastern KS and north-central/northwest OK, in close proximity to the surface low and front/dryline intersection. Rather strong (50-80 kt) southwesterly mid-level flow will overlie this region this afternoon/evening, along with enhanced south-southwesterly flow in the 850-700 mb layer. Related deep-layer shear around 45-60 kt will easily support supercells and associated threat for scattered hail initially. Isolated very large hail may occur from south-central KS into north-central OK with any sustained supercell given the rather favorable overlap of moderate instability with steepened mid-level lapse rates and strong deep-layer shear. With time this evening, upscale growth into a QLCS with greater threat for severe/damaging winds is anticipated. This severe/damaging wind threat should continue tonight as the line spreads eastward across IA/MO, before eventually becoming more isolated/diminishing with eastward extent into the mid MS Valley. The tornado potential should also increase late this afternoon and evening, as a southerly low-level jet and related 0-1 km SRH strengthens rapidly through 23-04Z. The potential for sustained supercells in central/eastern KS and north-central OK remains somewhat unclear, but any semi-discrete activity will pose a threat for tornadoes, a couple of which could be strong given the favorable low-level shear and hodograph curvature. Embedded mesovorticies within the QLCS will also be possible. Based on latest guidance and observational trends, severe probabilities have been expanded westward some across KS/OK, especially in the vicinity of the expected front/dryline intersection. The Enhanced Risk has also been expanded slightly eastward in western MO to account for scattered to numerous severe wind gusts with the QLCS this evening. Convective initiation may be delayed until around 00Z or later across central/eastern OK. But, potential for discrete supercells may be a bit better across this region given the dryline as the initiating boundary, and somewhat less large-scale ascent with southward extent away from the cold front. Any convection that can develop and be sustained will likely be supercellular for at least a couple of hours this evening, before upscale growth eventually occurs along the cold front. A threat for large hail and tornadoes will exist with any supercell, before the damaging wind threat increases as the convective mode becomes more linear. ...Southeast Texas... There is some potential that a few stronger/potentially rotating thunderstorms could materialize today across the region within a very moist and confluent low-level flow regime. This would be as low-level lapse rates diurnally steepen coincident with a moderate degree of low-level hodograph length and curvature. Modest-strength winds above 2km AGL should limit the sustainability and intensity for any showers/thunderstorms that may exhibit rotating characteristics, and the overall severe potential should tend to remain limited. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Wed Oct 30 2024 Valid 302000Z - 311200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS NORTHERN/CENTRAL OKLAHOMA INTO CENTRAL/EASTERN KANSAS AND WESTERN MISSOURI... ...SUMMARY... Severe thunderstorms capable of producing scattered large hail, numerous damaging wind gusts, and a few tornadoes are expected today into tonight across the middle Missouri Valley and central/southern Plains, including parts of eastern Kansas/Oklahoma into Missouri and vicinity. A strong tornado or two is possible across south-central/southeastern Kansas into central Oklahoma. ...20z Update... The Enhanced Risk was expanded further southward through the Oklahoma City metro with this update. The Slight Risk was also expanded further west and southward. Recent trends in satellite and radar have shown cell development further south and west along the dryline than previously forecast. The environment across central Oklahoma is favorable for maintenance of supercells, with daytime heating yielding MLCAPE around 1500 J/kg and shear around 40 kts progged to increase with the increasing low level jet this afternoon/evening. Boundary parallel shear and overtaking of the dryline by the cold front will lead to a transition to more linear structure around sunset. However, deep layer shear profiles will continue to support embedded supercell structures after dark with the potential for tornadoes, some strong, to continue through the evening. Large hail will also be a concern late afternoon/early evening while discrete mode is maintained. Tornado probabilities were adjusted across northeastern Kansas to account for progression of the cold front and earlier convective activity. See previous discussion for more information. ..Thornton/Gleason.. 10/30/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Wed Oct 30 2024/ ...Southern/Central Plains into the Mid Missouri Valley... The lead portion of an upper trough centered over the Rockies and Four Corners will eject northeastward over the central Plains today. A related surface low will likewise develop northeastward along a cold front from the southern High Plains to IA by this evening. A dryline extending southward from this low will mix eastward across western OK and west TX through late this afternoon before stalling. Robust low-level warm/moist advection will continue today across the southern/central Plains along and south/east of the cold front and dryline. Generally elevated thunderstorms have developed this morning across parts of central KS, as large-scale ascent preceding the ejecting upper trough has begun to overspread the central Plains. This activity should tend to remain just to the cool side of the front through the early afternoon. But, this convection may pose some threat for severe hail given sufficient MUCAPE with steepening mid-level lapse rates in the presence of strong deep-layer shear. There is also some chance it eventually becomes surface based later this afternoon across northeast KS. Otherwise, continued filtered daytime heating of the moistening warm sector should support around 500-1500 J/kg of MLCAPE by late afternoon from southern IA into eastern KS/western MO, and locally stronger to around 2000 J/kg in north-central OK. Current expectations are for surface-based thunderstorms to initiate by 20-22Z across central/eastern KS and north-central/northwest OK, in close proximity to the surface low and front/dryline intersection. Rather strong (50-80 kt) southwesterly mid-level flow will overlie this region this afternoon/evening, along with enhanced south-southwesterly flow in the 850-700 mb layer. Related deep-layer shear around 45-60 kt will easily support supercells and associated threat for scattered hail initially. Isolated very large hail may occur from south-central KS into north-central OK with any sustained supercell given the rather favorable overlap of moderate instability with steepened mid-level lapse rates and strong deep-layer shear. With time this evening, upscale growth into a QLCS with greater threat for severe/damaging winds is anticipated. This severe/damaging wind threat should continue tonight as the line spreads eastward across IA/MO, before eventually becoming more isolated/diminishing with eastward extent into the mid MS Valley. The tornado potential should also increase late this afternoon and evening, as a southerly low-level jet and related 0-1 km SRH strengthens rapidly through 23-04Z. The potential for sustained supercells in central/eastern KS and north-central OK remains somewhat unclear, but any semi-discrete activity will pose a threat for tornadoes, a couple of which could be strong given the favorable low-level shear and hodograph curvature. Embedded mesovorticies within the QLCS will also be possible. Based on latest guidance and observational trends, severe probabilities have been expanded westward some across KS/OK, especially in the vicinity of the expected front/dryline intersection. The Enhanced Risk has also been expanded slightly eastward in western MO to account for scattered to numerous severe wind gusts with the QLCS this evening. Convective initiation may be delayed until around 00Z or later across central/eastern OK. But, potential for discrete supercells may be a bit better across this region given the dryline as the initiating boundary, and somewhat less large-scale ascent with southward extent away from the cold front. Any convection that can develop and be sustained will likely be supercellular for at least a couple of hours this evening, before upscale growth eventually occurs along the cold front. A threat for large hail and tornadoes will exist with any supercell, before the damaging wind threat increases as the convective mode becomes more linear. ...Southeast Texas... There is some potential that a few stronger/potentially rotating thunderstorms could materialize today across the region within a very moist and confluent low-level flow regime. This would be as low-level lapse rates diurnally steepen coincident with a moderate degree of low-level hodograph length and curvature. Modest-strength winds above 2km AGL should limit the sustainability and intensity for any showers/thunderstorms that may exhibit rotating characteristics, and the overall severe potential should tend to remain limited. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Wed Oct 30 2024 Valid 302000Z - 311200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS NORTHERN/CENTRAL OKLAHOMA INTO CENTRAL/EASTERN KANSAS AND WESTERN MISSOURI... ...SUMMARY... Severe thunderstorms capable of producing scattered large hail, numerous damaging wind gusts, and a few tornadoes are expected today into tonight across the middle Missouri Valley and central/southern Plains, including parts of eastern Kansas/Oklahoma into Missouri and vicinity. A strong tornado or two is possible across south-central/southeastern Kansas into central Oklahoma. ...20z Update... The Enhanced Risk was expanded further southward through the Oklahoma City metro with this update. The Slight Risk was also expanded further west and southward. Recent trends in satellite and radar have shown cell development further south and west along the dryline than previously forecast. The environment across central Oklahoma is favorable for maintenance of supercells, with daytime heating yielding MLCAPE around 1500 J/kg and shear around 40 kts progged to increase with the increasing low level jet this afternoon/evening. Boundary parallel shear and overtaking of the dryline by the cold front will lead to a transition to more linear structure around sunset. However, deep layer shear profiles will continue to support embedded supercell structures after dark with the potential for tornadoes, some strong, to continue through the evening. Large hail will also be a concern late afternoon/early evening while discrete mode is maintained. Tornado probabilities were adjusted across northeastern Kansas to account for progression of the cold front and earlier convective activity. See previous discussion for more information. ..Thornton/Gleason.. 10/30/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Wed Oct 30 2024/ ...Southern/Central Plains into the Mid Missouri Valley... The lead portion of an upper trough centered over the Rockies and Four Corners will eject northeastward over the central Plains today. A related surface low will likewise develop northeastward along a cold front from the southern High Plains to IA by this evening. A dryline extending southward from this low will mix eastward across western OK and west TX through late this afternoon before stalling. Robust low-level warm/moist advection will continue today across the southern/central Plains along and south/east of the cold front and dryline. Generally elevated thunderstorms have developed this morning across parts of central KS, as large-scale ascent preceding the ejecting upper trough has begun to overspread the central Plains. This activity should tend to remain just to the cool side of the front through the early afternoon. But, this convection may pose some threat for severe hail given sufficient MUCAPE with steepening mid-level lapse rates in the presence of strong deep-layer shear. There is also some chance it eventually becomes surface based later this afternoon across northeast KS. Otherwise, continued filtered daytime heating of the moistening warm sector should support around 500-1500 J/kg of MLCAPE by late afternoon from southern IA into eastern KS/western MO, and locally stronger to around 2000 J/kg in north-central OK. Current expectations are for surface-based thunderstorms to initiate by 20-22Z across central/eastern KS and north-central/northwest OK, in close proximity to the surface low and front/dryline intersection. Rather strong (50-80 kt) southwesterly mid-level flow will overlie this region this afternoon/evening, along with enhanced south-southwesterly flow in the 850-700 mb layer. Related deep-layer shear around 45-60 kt will easily support supercells and associated threat for scattered hail initially. Isolated very large hail may occur from south-central KS into north-central OK with any sustained supercell given the rather favorable overlap of moderate instability with steepened mid-level lapse rates and strong deep-layer shear. With time this evening, upscale growth into a QLCS with greater threat for severe/damaging winds is anticipated. This severe/damaging wind threat should continue tonight as the line spreads eastward across IA/MO, before eventually becoming more isolated/diminishing with eastward extent into the mid MS Valley. The tornado potential should also increase late this afternoon and evening, as a southerly low-level jet and related 0-1 km SRH strengthens rapidly through 23-04Z. The potential for sustained supercells in central/eastern KS and north-central OK remains somewhat unclear, but any semi-discrete activity will pose a threat for tornadoes, a couple of which could be strong given the favorable low-level shear and hodograph curvature. Embedded mesovorticies within the QLCS will also be possible. Based on latest guidance and observational trends, severe probabilities have been expanded westward some across KS/OK, especially in the vicinity of the expected front/dryline intersection. The Enhanced Risk has also been expanded slightly eastward in western MO to account for scattered to numerous severe wind gusts with the QLCS this evening. Convective initiation may be delayed until around 00Z or later across central/eastern OK. But, potential for discrete supercells may be a bit better across this region given the dryline as the initiating boundary, and somewhat less large-scale ascent with southward extent away from the cold front. Any convection that can develop and be sustained will likely be supercellular for at least a couple of hours this evening, before upscale growth eventually occurs along the cold front. A threat for large hail and tornadoes will exist with any supercell, before the damaging wind threat increases as the convective mode becomes more linear. ...Southeast Texas... There is some potential that a few stronger/potentially rotating thunderstorms could materialize today across the region within a very moist and confluent low-level flow regime. This would be as low-level lapse rates diurnally steepen coincident with a moderate degree of low-level hodograph length and curvature. Modest-strength winds above 2km AGL should limit the sustainability and intensity for any showers/thunderstorms that may exhibit rotating characteristics, and the overall severe potential should tend to remain limited. Read more