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SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Tue Jun 18 2024 Valid 181630Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE UPPER MISSISSIPPI VALLEY INTO THE MID MISSOURI VALLEY/CENTRAL PLAINS AND SOUTHERN HIGH PLAINS... ...SUMMARY... Scattered strong to severe storms are expected this afternoon and evening over parts of the Upper Mississippi Valley southwestward into the central/southern High Plains. Large hail and severe/damaging winds should be the main threats, but a few tornadoes may also occur. ...Upper Mississippi Valley into the Mid Missouri Valley/Central Plains and Southern High Plains... A pronounced upper trough will advance eastward across the northern Plains and Canadian Prairie provinces today, with multiple embedded mid-level perturbations forecast to move northeastward across the northern/central Plains and upper MS Valley through the period. At the surface, a 997 mb low currently over eastern SD will develop northeastward towards the MN Arrowhead through this evening. A secondary surface low should remain located over the southern/central High Plains. Between these two lows, a surface cold front will continue to progress east-southeastward this afternoon and evening. This boundary will be the primary focus for severe thunderstorms today. Based on latest guidance, the broad Slight Risk extending from the upper MS Valley into the mid MO Valley/central Plains and southern High Plains has generally been expanded to account for severe/damaging wind potential continuing into at least mid evening. Current expectations are for robust thunderstorms to develop by early afternoon across the upper MS Valley and mid MO Valley along/near the cold front. With a rather moist airmass in place across these regions based on latest surface observations and area 12Z soundings, moderate instability is expected to develop this afternoon, even though cloud cover may temper diurnal heating to some extent, especially in MN. The stronger mid-level southwesterly flow should tend to remain displaced to the cool side of the surface front. Still, sufficient deep-layer shear should exist to support a mix of multicells and supercells with this initial development. Given the linear forcing of the front, upscale growth into multiple bowing clusters is anticipated later this afternoon and continuing into the evening. Both large hail and severe/damaging winds appear possible, with a transition to a mainly damaging wind threat as clusters become dominant. Enough low-level shear may also support some threat for a few tornadoes, especially in MN with any supercell that can be maintained. Additional intense convective development is expected with southward extent into the central Plains along the front, perhaps delayed until a little later in the afternoon as stronger daytime heating will be needed to erode a cap/lingering MLCIN. Strong instability and deep-layer shear should be present over parts of western/central KS, where multiple supercells may develop near/east of the secondary surface low. Isolated very large hail may occur with this activity given the favorable environment and presence of steep mid-level lapse rates. A few tornadoes may also occur in a narrow corridor across southwest KS this evening if supercells can be maintained as low-level shear increases. Otherwise, severe/damaging winds (with perhaps some reaching 75-80 mph on an isolated basis) appear probable as convection likely grows upscale into a bowing cluster across central KS late this afternoon/early evening. Scattered thunderstorms may also develop across the southern High Plains (OK/TX Panhandle regions) along/east of a dryline. Severe wind gusts should be the main threat if this activity occurs, as the boundary layer is forecast to become very well mixed, with steep low-level lapse rates present. ...Lower Great Lakes/Upper Ohio Valley into the Northeast... Recent water vapor satellite and radar imagery show multiple widely dispersed thunderstorm clusters and remnant MCVs present across the lower Great Lakes into the Northeast. This activity is occurring on the western/northern periphery of a prominent upper ridge centered over the Mid-Atlantic States and Carolinas. Surface heating will aid ample destabilization this afternoon across a broad portion of the upper OH River Valley into upstate New York and northern New England. Isolated to widely scattered thunderstorms will once again develop and increase into the afternoon, influenced in some areas by the aforementioned MCVs. Localized downbursts with strong/damaging wind gusts will be possible through the diurnal heating cycle. Have maintained a broad Marginal Risk to account for this potential, as confidence in a more focused corridor of damaging wind potential remains low. ...Lower/Middle Texas Coast... Low-level easterly flow will gradually increase late tonight into early Wednesday morning as Potential Tropical Cyclone 1 develops and moves westward over the southwest Gulf, per latest NHC forecast. While instability should remain weak, with poor lapse rates aloft, strengthening low-level shear may support a low chance for a tornado with any low-topped cells that can approach/reach parts of the lower/middle TX Coast near the end of the Day 1 period. This threat should continue into the Day 2/Wednesday time frame. ..Gleason/Halbert/Lyons.. 06/18/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Tue Jun 18 2024 Valid 181630Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE UPPER MISSISSIPPI VALLEY INTO THE MID MISSOURI VALLEY/CENTRAL PLAINS AND SOUTHERN HIGH PLAINS... ...SUMMARY... Scattered strong to severe storms are expected this afternoon and evening over parts of the Upper Mississippi Valley southwestward into the central/southern High Plains. Large hail and severe/damaging winds should be the main threats, but a few tornadoes may also occur. ...Upper Mississippi Valley into the Mid Missouri Valley/Central Plains and Southern High Plains... A pronounced upper trough will advance eastward across the northern Plains and Canadian Prairie provinces today, with multiple embedded mid-level perturbations forecast to move northeastward across the northern/central Plains and upper MS Valley through the period. At the surface, a 997 mb low currently over eastern SD will develop northeastward towards the MN Arrowhead through this evening. A secondary surface low should remain located over the southern/central High Plains. Between these two lows, a surface cold front will continue to progress east-southeastward this afternoon and evening. This boundary will be the primary focus for severe thunderstorms today. Based on latest guidance, the broad Slight Risk extending from the upper MS Valley into the mid MO Valley/central Plains and southern High Plains has generally been expanded to account for severe/damaging wind potential continuing into at least mid evening. Current expectations are for robust thunderstorms to develop by early afternoon across the upper MS Valley and mid MO Valley along/near the cold front. With a rather moist airmass in place across these regions based on latest surface observations and area 12Z soundings, moderate instability is expected to develop this afternoon, even though cloud cover may temper diurnal heating to some extent, especially in MN. The stronger mid-level southwesterly flow should tend to remain displaced to the cool side of the surface front. Still, sufficient deep-layer shear should exist to support a mix of multicells and supercells with this initial development. Given the linear forcing of the front, upscale growth into multiple bowing clusters is anticipated later this afternoon and continuing into the evening. Both large hail and severe/damaging winds appear possible, with a transition to a mainly damaging wind threat as clusters become dominant. Enough low-level shear may also support some threat for a few tornadoes, especially in MN with any supercell that can be maintained. Additional intense convective development is expected with southward extent into the central Plains along the front, perhaps delayed until a little later in the afternoon as stronger daytime heating will be needed to erode a cap/lingering MLCIN. Strong instability and deep-layer shear should be present over parts of western/central KS, where multiple supercells may develop near/east of the secondary surface low. Isolated very large hail may occur with this activity given the favorable environment and presence of steep mid-level lapse rates. A few tornadoes may also occur in a narrow corridor across southwest KS this evening if supercells can be maintained as low-level shear increases. Otherwise, severe/damaging winds (with perhaps some reaching 75-80 mph on an isolated basis) appear probable as convection likely grows upscale into a bowing cluster across central KS late this afternoon/early evening. Scattered thunderstorms may also develop across the southern High Plains (OK/TX Panhandle regions) along/east of a dryline. Severe wind gusts should be the main threat if this activity occurs, as the boundary layer is forecast to become very well mixed, with steep low-level lapse rates present. ...Lower Great Lakes/Upper Ohio Valley into the Northeast... Recent water vapor satellite and radar imagery show multiple widely dispersed thunderstorm clusters and remnant MCVs present across the lower Great Lakes into the Northeast. This activity is occurring on the western/northern periphery of a prominent upper ridge centered over the Mid-Atlantic States and Carolinas. Surface heating will aid ample destabilization this afternoon across a broad portion of the upper OH River Valley into upstate New York and northern New England. Isolated to widely scattered thunderstorms will once again develop and increase into the afternoon, influenced in some areas by the aforementioned MCVs. Localized downbursts with strong/damaging wind gusts will be possible through the diurnal heating cycle. Have maintained a broad Marginal Risk to account for this potential, as confidence in a more focused corridor of damaging wind potential remains low. ...Lower/Middle Texas Coast... Low-level easterly flow will gradually increase late tonight into early Wednesday morning as Potential Tropical Cyclone 1 develops and moves westward over the southwest Gulf, per latest NHC forecast. While instability should remain weak, with poor lapse rates aloft, strengthening low-level shear may support a low chance for a tornado with any low-topped cells that can approach/reach parts of the lower/middle TX Coast near the end of the Day 1 period. This threat should continue into the Day 2/Wednesday time frame. ..Gleason/Halbert/Lyons.. 06/18/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Tue Jun 18 2024 Valid 181630Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE UPPER MISSISSIPPI VALLEY INTO THE MID MISSOURI VALLEY/CENTRAL PLAINS AND SOUTHERN HIGH PLAINS... ...SUMMARY... Scattered strong to severe storms are expected this afternoon and evening over parts of the Upper Mississippi Valley southwestward into the central/southern High Plains. Large hail and severe/damaging winds should be the main threats, but a few tornadoes may also occur. ...Upper Mississippi Valley into the Mid Missouri Valley/Central Plains and Southern High Plains... A pronounced upper trough will advance eastward across the northern Plains and Canadian Prairie provinces today, with multiple embedded mid-level perturbations forecast to move northeastward across the northern/central Plains and upper MS Valley through the period. At the surface, a 997 mb low currently over eastern SD will develop northeastward towards the MN Arrowhead through this evening. A secondary surface low should remain located over the southern/central High Plains. Between these two lows, a surface cold front will continue to progress east-southeastward this afternoon and evening. This boundary will be the primary focus for severe thunderstorms today. Based on latest guidance, the broad Slight Risk extending from the upper MS Valley into the mid MO Valley/central Plains and southern High Plains has generally been expanded to account for severe/damaging wind potential continuing into at least mid evening. Current expectations are for robust thunderstorms to develop by early afternoon across the upper MS Valley and mid MO Valley along/near the cold front. With a rather moist airmass in place across these regions based on latest surface observations and area 12Z soundings, moderate instability is expected to develop this afternoon, even though cloud cover may temper diurnal heating to some extent, especially in MN. The stronger mid-level southwesterly flow should tend to remain displaced to the cool side of the surface front. Still, sufficient deep-layer shear should exist to support a mix of multicells and supercells with this initial development. Given the linear forcing of the front, upscale growth into multiple bowing clusters is anticipated later this afternoon and continuing into the evening. Both large hail and severe/damaging winds appear possible, with a transition to a mainly damaging wind threat as clusters become dominant. Enough low-level shear may also support some threat for a few tornadoes, especially in MN with any supercell that can be maintained. Additional intense convective development is expected with southward extent into the central Plains along the front, perhaps delayed until a little later in the afternoon as stronger daytime heating will be needed to erode a cap/lingering MLCIN. Strong instability and deep-layer shear should be present over parts of western/central KS, where multiple supercells may develop near/east of the secondary surface low. Isolated very large hail may occur with this activity given the favorable environment and presence of steep mid-level lapse rates. A few tornadoes may also occur in a narrow corridor across southwest KS this evening if supercells can be maintained as low-level shear increases. Otherwise, severe/damaging winds (with perhaps some reaching 75-80 mph on an isolated basis) appear probable as convection likely grows upscale into a bowing cluster across central KS late this afternoon/early evening. Scattered thunderstorms may also develop across the southern High Plains (OK/TX Panhandle regions) along/east of a dryline. Severe wind gusts should be the main threat if this activity occurs, as the boundary layer is forecast to become very well mixed, with steep low-level lapse rates present. ...Lower Great Lakes/Upper Ohio Valley into the Northeast... Recent water vapor satellite and radar imagery show multiple widely dispersed thunderstorm clusters and remnant MCVs present across the lower Great Lakes into the Northeast. This activity is occurring on the western/northern periphery of a prominent upper ridge centered over the Mid-Atlantic States and Carolinas. Surface heating will aid ample destabilization this afternoon across a broad portion of the upper OH River Valley into upstate New York and northern New England. Isolated to widely scattered thunderstorms will once again develop and increase into the afternoon, influenced in some areas by the aforementioned MCVs. Localized downbursts with strong/damaging wind gusts will be possible through the diurnal heating cycle. Have maintained a broad Marginal Risk to account for this potential, as confidence in a more focused corridor of damaging wind potential remains low. ...Lower/Middle Texas Coast... Low-level easterly flow will gradually increase late tonight into early Wednesday morning as Potential Tropical Cyclone 1 develops and moves westward over the southwest Gulf, per latest NHC forecast. While instability should remain weak, with poor lapse rates aloft, strengthening low-level shear may support a low chance for a tornado with any low-topped cells that can approach/reach parts of the lower/middle TX Coast near the end of the Day 1 period. This threat should continue into the Day 2/Wednesday time frame. ..Gleason/Halbert/Lyons.. 06/18/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Tue Jun 18 2024 Valid 181630Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE UPPER MISSISSIPPI VALLEY INTO THE MID MISSOURI VALLEY/CENTRAL PLAINS AND SOUTHERN HIGH PLAINS... ...SUMMARY... Scattered strong to severe storms are expected this afternoon and evening over parts of the Upper Mississippi Valley southwestward into the central/southern High Plains. Large hail and severe/damaging winds should be the main threats, but a few tornadoes may also occur. ...Upper Mississippi Valley into the Mid Missouri Valley/Central Plains and Southern High Plains... A pronounced upper trough will advance eastward across the northern Plains and Canadian Prairie provinces today, with multiple embedded mid-level perturbations forecast to move northeastward across the northern/central Plains and upper MS Valley through the period. At the surface, a 997 mb low currently over eastern SD will develop northeastward towards the MN Arrowhead through this evening. A secondary surface low should remain located over the southern/central High Plains. Between these two lows, a surface cold front will continue to progress east-southeastward this afternoon and evening. This boundary will be the primary focus for severe thunderstorms today. Based on latest guidance, the broad Slight Risk extending from the upper MS Valley into the mid MO Valley/central Plains and southern High Plains has generally been expanded to account for severe/damaging wind potential continuing into at least mid evening. Current expectations are for robust thunderstorms to develop by early afternoon across the upper MS Valley and mid MO Valley along/near the cold front. With a rather moist airmass in place across these regions based on latest surface observations and area 12Z soundings, moderate instability is expected to develop this afternoon, even though cloud cover may temper diurnal heating to some extent, especially in MN. The stronger mid-level southwesterly flow should tend to remain displaced to the cool side of the surface front. Still, sufficient deep-layer shear should exist to support a mix of multicells and supercells with this initial development. Given the linear forcing of the front, upscale growth into multiple bowing clusters is anticipated later this afternoon and continuing into the evening. Both large hail and severe/damaging winds appear possible, with a transition to a mainly damaging wind threat as clusters become dominant. Enough low-level shear may also support some threat for a few tornadoes, especially in MN with any supercell that can be maintained. Additional intense convective development is expected with southward extent into the central Plains along the front, perhaps delayed until a little later in the afternoon as stronger daytime heating will be needed to erode a cap/lingering MLCIN. Strong instability and deep-layer shear should be present over parts of western/central KS, where multiple supercells may develop near/east of the secondary surface low. Isolated very large hail may occur with this activity given the favorable environment and presence of steep mid-level lapse rates. A few tornadoes may also occur in a narrow corridor across southwest KS this evening if supercells can be maintained as low-level shear increases. Otherwise, severe/damaging winds (with perhaps some reaching 75-80 mph on an isolated basis) appear probable as convection likely grows upscale into a bowing cluster across central KS late this afternoon/early evening. Scattered thunderstorms may also develop across the southern High Plains (OK/TX Panhandle regions) along/east of a dryline. Severe wind gusts should be the main threat if this activity occurs, as the boundary layer is forecast to become very well mixed, with steep low-level lapse rates present. ...Lower Great Lakes/Upper Ohio Valley into the Northeast... Recent water vapor satellite and radar imagery show multiple widely dispersed thunderstorm clusters and remnant MCVs present across the lower Great Lakes into the Northeast. This activity is occurring on the western/northern periphery of a prominent upper ridge centered over the Mid-Atlantic States and Carolinas. Surface heating will aid ample destabilization this afternoon across a broad portion of the upper OH River Valley into upstate New York and northern New England. Isolated to widely scattered thunderstorms will once again develop and increase into the afternoon, influenced in some areas by the aforementioned MCVs. Localized downbursts with strong/damaging wind gusts will be possible through the diurnal heating cycle. Have maintained a broad Marginal Risk to account for this potential, as confidence in a more focused corridor of damaging wind potential remains low. ...Lower/Middle Texas Coast... Low-level easterly flow will gradually increase late tonight into early Wednesday morning as Potential Tropical Cyclone 1 develops and moves westward over the southwest Gulf, per latest NHC forecast. While instability should remain weak, with poor lapse rates aloft, strengthening low-level shear may support a low chance for a tornado with any low-topped cells that can approach/reach parts of the lower/middle TX Coast near the end of the Day 1 period. This threat should continue into the Day 2/Wednesday time frame. ..Gleason/Halbert/Lyons.. 06/18/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Tue Jun 18 2024 Valid 181630Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE UPPER MISSISSIPPI VALLEY INTO THE MID MISSOURI VALLEY/CENTRAL PLAINS AND SOUTHERN HIGH PLAINS... ...SUMMARY... Scattered strong to severe storms are expected this afternoon and evening over parts of the Upper Mississippi Valley southwestward into the central/southern High Plains. Large hail and severe/damaging winds should be the main threats, but a few tornadoes may also occur. ...Upper Mississippi Valley into the Mid Missouri Valley/Central Plains and Southern High Plains... A pronounced upper trough will advance eastward across the northern Plains and Canadian Prairie provinces today, with multiple embedded mid-level perturbations forecast to move northeastward across the northern/central Plains and upper MS Valley through the period. At the surface, a 997 mb low currently over eastern SD will develop northeastward towards the MN Arrowhead through this evening. A secondary surface low should remain located over the southern/central High Plains. Between these two lows, a surface cold front will continue to progress east-southeastward this afternoon and evening. This boundary will be the primary focus for severe thunderstorms today. Based on latest guidance, the broad Slight Risk extending from the upper MS Valley into the mid MO Valley/central Plains and southern High Plains has generally been expanded to account for severe/damaging wind potential continuing into at least mid evening. Current expectations are for robust thunderstorms to develop by early afternoon across the upper MS Valley and mid MO Valley along/near the cold front. With a rather moist airmass in place across these regions based on latest surface observations and area 12Z soundings, moderate instability is expected to develop this afternoon, even though cloud cover may temper diurnal heating to some extent, especially in MN. The stronger mid-level southwesterly flow should tend to remain displaced to the cool side of the surface front. Still, sufficient deep-layer shear should exist to support a mix of multicells and supercells with this initial development. Given the linear forcing of the front, upscale growth into multiple bowing clusters is anticipated later this afternoon and continuing into the evening. Both large hail and severe/damaging winds appear possible, with a transition to a mainly damaging wind threat as clusters become dominant. Enough low-level shear may also support some threat for a few tornadoes, especially in MN with any supercell that can be maintained. Additional intense convective development is expected with southward extent into the central Plains along the front, perhaps delayed until a little later in the afternoon as stronger daytime heating will be needed to erode a cap/lingering MLCIN. Strong instability and deep-layer shear should be present over parts of western/central KS, where multiple supercells may develop near/east of the secondary surface low. Isolated very large hail may occur with this activity given the favorable environment and presence of steep mid-level lapse rates. A few tornadoes may also occur in a narrow corridor across southwest KS this evening if supercells can be maintained as low-level shear increases. Otherwise, severe/damaging winds (with perhaps some reaching 75-80 mph on an isolated basis) appear probable as convection likely grows upscale into a bowing cluster across central KS late this afternoon/early evening. Scattered thunderstorms may also develop across the southern High Plains (OK/TX Panhandle regions) along/east of a dryline. Severe wind gusts should be the main threat if this activity occurs, as the boundary layer is forecast to become very well mixed, with steep low-level lapse rates present. ...Lower Great Lakes/Upper Ohio Valley into the Northeast... Recent water vapor satellite and radar imagery show multiple widely dispersed thunderstorm clusters and remnant MCVs present across the lower Great Lakes into the Northeast. This activity is occurring on the western/northern periphery of a prominent upper ridge centered over the Mid-Atlantic States and Carolinas. Surface heating will aid ample destabilization this afternoon across a broad portion of the upper OH River Valley into upstate New York and northern New England. Isolated to widely scattered thunderstorms will once again develop and increase into the afternoon, influenced in some areas by the aforementioned MCVs. Localized downbursts with strong/damaging wind gusts will be possible through the diurnal heating cycle. Have maintained a broad Marginal Risk to account for this potential, as confidence in a more focused corridor of damaging wind potential remains low. ...Lower/Middle Texas Coast... Low-level easterly flow will gradually increase late tonight into early Wednesday morning as Potential Tropical Cyclone 1 develops and moves westward over the southwest Gulf, per latest NHC forecast. While instability should remain weak, with poor lapse rates aloft, strengthening low-level shear may support a low chance for a tornado with any low-topped cells that can approach/reach parts of the lower/middle TX Coast near the end of the Day 1 period. This threat should continue into the Day 2/Wednesday time frame. ..Gleason/Halbert/Lyons.. 06/18/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Tue Jun 18 2024 Valid 181630Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE UPPER MISSISSIPPI VALLEY INTO THE MID MISSOURI VALLEY/CENTRAL PLAINS AND SOUTHERN HIGH PLAINS... ...SUMMARY... Scattered strong to severe storms are expected this afternoon and evening over parts of the Upper Mississippi Valley southwestward into the central/southern High Plains. Large hail and severe/damaging winds should be the main threats, but a few tornadoes may also occur. ...Upper Mississippi Valley into the Mid Missouri Valley/Central Plains and Southern High Plains... A pronounced upper trough will advance eastward across the northern Plains and Canadian Prairie provinces today, with multiple embedded mid-level perturbations forecast to move northeastward across the northern/central Plains and upper MS Valley through the period. At the surface, a 997 mb low currently over eastern SD will develop northeastward towards the MN Arrowhead through this evening. A secondary surface low should remain located over the southern/central High Plains. Between these two lows, a surface cold front will continue to progress east-southeastward this afternoon and evening. This boundary will be the primary focus for severe thunderstorms today. Based on latest guidance, the broad Slight Risk extending from the upper MS Valley into the mid MO Valley/central Plains and southern High Plains has generally been expanded to account for severe/damaging wind potential continuing into at least mid evening. Current expectations are for robust thunderstorms to develop by early afternoon across the upper MS Valley and mid MO Valley along/near the cold front. With a rather moist airmass in place across these regions based on latest surface observations and area 12Z soundings, moderate instability is expected to develop this afternoon, even though cloud cover may temper diurnal heating to some extent, especially in MN. The stronger mid-level southwesterly flow should tend to remain displaced to the cool side of the surface front. Still, sufficient deep-layer shear should exist to support a mix of multicells and supercells with this initial development. Given the linear forcing of the front, upscale growth into multiple bowing clusters is anticipated later this afternoon and continuing into the evening. Both large hail and severe/damaging winds appear possible, with a transition to a mainly damaging wind threat as clusters become dominant. Enough low-level shear may also support some threat for a few tornadoes, especially in MN with any supercell that can be maintained. Additional intense convective development is expected with southward extent into the central Plains along the front, perhaps delayed until a little later in the afternoon as stronger daytime heating will be needed to erode a cap/lingering MLCIN. Strong instability and deep-layer shear should be present over parts of western/central KS, where multiple supercells may develop near/east of the secondary surface low. Isolated very large hail may occur with this activity given the favorable environment and presence of steep mid-level lapse rates. A few tornadoes may also occur in a narrow corridor across southwest KS this evening if supercells can be maintained as low-level shear increases. Otherwise, severe/damaging winds (with perhaps some reaching 75-80 mph on an isolated basis) appear probable as convection likely grows upscale into a bowing cluster across central KS late this afternoon/early evening. Scattered thunderstorms may also develop across the southern High Plains (OK/TX Panhandle regions) along/east of a dryline. Severe wind gusts should be the main threat if this activity occurs, as the boundary layer is forecast to become very well mixed, with steep low-level lapse rates present. ...Lower Great Lakes/Upper Ohio Valley into the Northeast... Recent water vapor satellite and radar imagery show multiple widely dispersed thunderstorm clusters and remnant MCVs present across the lower Great Lakes into the Northeast. This activity is occurring on the western/northern periphery of a prominent upper ridge centered over the Mid-Atlantic States and Carolinas. Surface heating will aid ample destabilization this afternoon across a broad portion of the upper OH River Valley into upstate New York and northern New England. Isolated to widely scattered thunderstorms will once again develop and increase into the afternoon, influenced in some areas by the aforementioned MCVs. Localized downbursts with strong/damaging wind gusts will be possible through the diurnal heating cycle. Have maintained a broad Marginal Risk to account for this potential, as confidence in a more focused corridor of damaging wind potential remains low. ...Lower/Middle Texas Coast... Low-level easterly flow will gradually increase late tonight into early Wednesday morning as Potential Tropical Cyclone 1 develops and moves westward over the southwest Gulf, per latest NHC forecast. While instability should remain weak, with poor lapse rates aloft, strengthening low-level shear may support a low chance for a tornado with any low-topped cells that can approach/reach parts of the lower/middle TX Coast near the end of the Day 1 period. This threat should continue into the Day 2/Wednesday time frame. ..Gleason/Halbert/Lyons.. 06/18/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Tue Jun 18 2024 Valid 181630Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE UPPER MISSISSIPPI VALLEY INTO THE MID MISSOURI VALLEY/CENTRAL PLAINS AND SOUTHERN HIGH PLAINS... ...SUMMARY... Scattered strong to severe storms are expected this afternoon and evening over parts of the Upper Mississippi Valley southwestward into the central/southern High Plains. Large hail and severe/damaging winds should be the main threats, but a few tornadoes may also occur. ...Upper Mississippi Valley into the Mid Missouri Valley/Central Plains and Southern High Plains... A pronounced upper trough will advance eastward across the northern Plains and Canadian Prairie provinces today, with multiple embedded mid-level perturbations forecast to move northeastward across the northern/central Plains and upper MS Valley through the period. At the surface, a 997 mb low currently over eastern SD will develop northeastward towards the MN Arrowhead through this evening. A secondary surface low should remain located over the southern/central High Plains. Between these two lows, a surface cold front will continue to progress east-southeastward this afternoon and evening. This boundary will be the primary focus for severe thunderstorms today. Based on latest guidance, the broad Slight Risk extending from the upper MS Valley into the mid MO Valley/central Plains and southern High Plains has generally been expanded to account for severe/damaging wind potential continuing into at least mid evening. Current expectations are for robust thunderstorms to develop by early afternoon across the upper MS Valley and mid MO Valley along/near the cold front. With a rather moist airmass in place across these regions based on latest surface observations and area 12Z soundings, moderate instability is expected to develop this afternoon, even though cloud cover may temper diurnal heating to some extent, especially in MN. The stronger mid-level southwesterly flow should tend to remain displaced to the cool side of the surface front. Still, sufficient deep-layer shear should exist to support a mix of multicells and supercells with this initial development. Given the linear forcing of the front, upscale growth into multiple bowing clusters is anticipated later this afternoon and continuing into the evening. Both large hail and severe/damaging winds appear possible, with a transition to a mainly damaging wind threat as clusters become dominant. Enough low-level shear may also support some threat for a few tornadoes, especially in MN with any supercell that can be maintained. Additional intense convective development is expected with southward extent into the central Plains along the front, perhaps delayed until a little later in the afternoon as stronger daytime heating will be needed to erode a cap/lingering MLCIN. Strong instability and deep-layer shear should be present over parts of western/central KS, where multiple supercells may develop near/east of the secondary surface low. Isolated very large hail may occur with this activity given the favorable environment and presence of steep mid-level lapse rates. A few tornadoes may also occur in a narrow corridor across southwest KS this evening if supercells can be maintained as low-level shear increases. Otherwise, severe/damaging winds (with perhaps some reaching 75-80 mph on an isolated basis) appear probable as convection likely grows upscale into a bowing cluster across central KS late this afternoon/early evening. Scattered thunderstorms may also develop across the southern High Plains (OK/TX Panhandle regions) along/east of a dryline. Severe wind gusts should be the main threat if this activity occurs, as the boundary layer is forecast to become very well mixed, with steep low-level lapse rates present. ...Lower Great Lakes/Upper Ohio Valley into the Northeast... Recent water vapor satellite and radar imagery show multiple widely dispersed thunderstorm clusters and remnant MCVs present across the lower Great Lakes into the Northeast. This activity is occurring on the western/northern periphery of a prominent upper ridge centered over the Mid-Atlantic States and Carolinas. Surface heating will aid ample destabilization this afternoon across a broad portion of the upper OH River Valley into upstate New York and northern New England. Isolated to widely scattered thunderstorms will once again develop and increase into the afternoon, influenced in some areas by the aforementioned MCVs. Localized downbursts with strong/damaging wind gusts will be possible through the diurnal heating cycle. Have maintained a broad Marginal Risk to account for this potential, as confidence in a more focused corridor of damaging wind potential remains low. ...Lower/Middle Texas Coast... Low-level easterly flow will gradually increase late tonight into early Wednesday morning as Potential Tropical Cyclone 1 develops and moves westward over the southwest Gulf, per latest NHC forecast. While instability should remain weak, with poor lapse rates aloft, strengthening low-level shear may support a low chance for a tornado with any low-topped cells that can approach/reach parts of the lower/middle TX Coast near the end of the Day 1 period. This threat should continue into the Day 2/Wednesday time frame. ..Gleason/Halbert/Lyons.. 06/18/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Tue Jun 18 2024 Valid 181630Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE UPPER MISSISSIPPI VALLEY INTO THE MID MISSOURI VALLEY/CENTRAL PLAINS AND SOUTHERN HIGH PLAINS... ...SUMMARY... Scattered strong to severe storms are expected this afternoon and evening over parts of the Upper Mississippi Valley southwestward into the central/southern High Plains. Large hail and severe/damaging winds should be the main threats, but a few tornadoes may also occur. ...Upper Mississippi Valley into the Mid Missouri Valley/Central Plains and Southern High Plains... A pronounced upper trough will advance eastward across the northern Plains and Canadian Prairie provinces today, with multiple embedded mid-level perturbations forecast to move northeastward across the northern/central Plains and upper MS Valley through the period. At the surface, a 997 mb low currently over eastern SD will develop northeastward towards the MN Arrowhead through this evening. A secondary surface low should remain located over the southern/central High Plains. Between these two lows, a surface cold front will continue to progress east-southeastward this afternoon and evening. This boundary will be the primary focus for severe thunderstorms today. Based on latest guidance, the broad Slight Risk extending from the upper MS Valley into the mid MO Valley/central Plains and southern High Plains has generally been expanded to account for severe/damaging wind potential continuing into at least mid evening. Current expectations are for robust thunderstorms to develop by early afternoon across the upper MS Valley and mid MO Valley along/near the cold front. With a rather moist airmass in place across these regions based on latest surface observations and area 12Z soundings, moderate instability is expected to develop this afternoon, even though cloud cover may temper diurnal heating to some extent, especially in MN. The stronger mid-level southwesterly flow should tend to remain displaced to the cool side of the surface front. Still, sufficient deep-layer shear should exist to support a mix of multicells and supercells with this initial development. Given the linear forcing of the front, upscale growth into multiple bowing clusters is anticipated later this afternoon and continuing into the evening. Both large hail and severe/damaging winds appear possible, with a transition to a mainly damaging wind threat as clusters become dominant. Enough low-level shear may also support some threat for a few tornadoes, especially in MN with any supercell that can be maintained. Additional intense convective development is expected with southward extent into the central Plains along the front, perhaps delayed until a little later in the afternoon as stronger daytime heating will be needed to erode a cap/lingering MLCIN. Strong instability and deep-layer shear should be present over parts of western/central KS, where multiple supercells may develop near/east of the secondary surface low. Isolated very large hail may occur with this activity given the favorable environment and presence of steep mid-level lapse rates. A few tornadoes may also occur in a narrow corridor across southwest KS this evening if supercells can be maintained as low-level shear increases. Otherwise, severe/damaging winds (with perhaps some reaching 75-80 mph on an isolated basis) appear probable as convection likely grows upscale into a bowing cluster across central KS late this afternoon/early evening. Scattered thunderstorms may also develop across the southern High Plains (OK/TX Panhandle regions) along/east of a dryline. Severe wind gusts should be the main threat if this activity occurs, as the boundary layer is forecast to become very well mixed, with steep low-level lapse rates present. ...Lower Great Lakes/Upper Ohio Valley into the Northeast... Recent water vapor satellite and radar imagery show multiple widely dispersed thunderstorm clusters and remnant MCVs present across the lower Great Lakes into the Northeast. This activity is occurring on the western/northern periphery of a prominent upper ridge centered over the Mid-Atlantic States and Carolinas. Surface heating will aid ample destabilization this afternoon across a broad portion of the upper OH River Valley into upstate New York and northern New England. Isolated to widely scattered thunderstorms will once again develop and increase into the afternoon, influenced in some areas by the aforementioned MCVs. Localized downbursts with strong/damaging wind gusts will be possible through the diurnal heating cycle. Have maintained a broad Marginal Risk to account for this potential, as confidence in a more focused corridor of damaging wind potential remains low. ...Lower/Middle Texas Coast... Low-level easterly flow will gradually increase late tonight into early Wednesday morning as Potential Tropical Cyclone 1 develops and moves westward over the southwest Gulf, per latest NHC forecast. While instability should remain weak, with poor lapse rates aloft, strengthening low-level shear may support a low chance for a tornado with any low-topped cells that can approach/reach parts of the lower/middle TX Coast near the end of the Day 1 period. This threat should continue into the Day 2/Wednesday time frame. ..Gleason/Halbert/Lyons.. 06/18/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Tue Jun 18 2024 Valid 181630Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE UPPER MISSISSIPPI VALLEY INTO THE MID MISSOURI VALLEY/CENTRAL PLAINS AND SOUTHERN HIGH PLAINS... ...SUMMARY... Scattered strong to severe storms are expected this afternoon and evening over parts of the Upper Mississippi Valley southwestward into the central/southern High Plains. Large hail and severe/damaging winds should be the main threats, but a few tornadoes may also occur. ...Upper Mississippi Valley into the Mid Missouri Valley/Central Plains and Southern High Plains... A pronounced upper trough will advance eastward across the northern Plains and Canadian Prairie provinces today, with multiple embedded mid-level perturbations forecast to move northeastward across the northern/central Plains and upper MS Valley through the period. At the surface, a 997 mb low currently over eastern SD will develop northeastward towards the MN Arrowhead through this evening. A secondary surface low should remain located over the southern/central High Plains. Between these two lows, a surface cold front will continue to progress east-southeastward this afternoon and evening. This boundary will be the primary focus for severe thunderstorms today. Based on latest guidance, the broad Slight Risk extending from the upper MS Valley into the mid MO Valley/central Plains and southern High Plains has generally been expanded to account for severe/damaging wind potential continuing into at least mid evening. Current expectations are for robust thunderstorms to develop by early afternoon across the upper MS Valley and mid MO Valley along/near the cold front. With a rather moist airmass in place across these regions based on latest surface observations and area 12Z soundings, moderate instability is expected to develop this afternoon, even though cloud cover may temper diurnal heating to some extent, especially in MN. The stronger mid-level southwesterly flow should tend to remain displaced to the cool side of the surface front. Still, sufficient deep-layer shear should exist to support a mix of multicells and supercells with this initial development. Given the linear forcing of the front, upscale growth into multiple bowing clusters is anticipated later this afternoon and continuing into the evening. Both large hail and severe/damaging winds appear possible, with a transition to a mainly damaging wind threat as clusters become dominant. Enough low-level shear may also support some threat for a few tornadoes, especially in MN with any supercell that can be maintained. Additional intense convective development is expected with southward extent into the central Plains along the front, perhaps delayed until a little later in the afternoon as stronger daytime heating will be needed to erode a cap/lingering MLCIN. Strong instability and deep-layer shear should be present over parts of western/central KS, where multiple supercells may develop near/east of the secondary surface low. Isolated very large hail may occur with this activity given the favorable environment and presence of steep mid-level lapse rates. A few tornadoes may also occur in a narrow corridor across southwest KS this evening if supercells can be maintained as low-level shear increases. Otherwise, severe/damaging winds (with perhaps some reaching 75-80 mph on an isolated basis) appear probable as convection likely grows upscale into a bowing cluster across central KS late this afternoon/early evening. Scattered thunderstorms may also develop across the southern High Plains (OK/TX Panhandle regions) along/east of a dryline. Severe wind gusts should be the main threat if this activity occurs, as the boundary layer is forecast to become very well mixed, with steep low-level lapse rates present. ...Lower Great Lakes/Upper Ohio Valley into the Northeast... Recent water vapor satellite and radar imagery show multiple widely dispersed thunderstorm clusters and remnant MCVs present across the lower Great Lakes into the Northeast. This activity is occurring on the western/northern periphery of a prominent upper ridge centered over the Mid-Atlantic States and Carolinas. Surface heating will aid ample destabilization this afternoon across a broad portion of the upper OH River Valley into upstate New York and northern New England. Isolated to widely scattered thunderstorms will once again develop and increase into the afternoon, influenced in some areas by the aforementioned MCVs. Localized downbursts with strong/damaging wind gusts will be possible through the diurnal heating cycle. Have maintained a broad Marginal Risk to account for this potential, as confidence in a more focused corridor of damaging wind potential remains low. ...Lower/Middle Texas Coast... Low-level easterly flow will gradually increase late tonight into early Wednesday morning as Potential Tropical Cyclone 1 develops and moves westward over the southwest Gulf, per latest NHC forecast. While instability should remain weak, with poor lapse rates aloft, strengthening low-level shear may support a low chance for a tornado with any low-topped cells that can approach/reach parts of the lower/middle TX Coast near the end of the Day 1 period. This threat should continue into the Day 2/Wednesday time frame. ..Gleason/Halbert/Lyons.. 06/18/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Tue Jun 18 2024 Valid 181630Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE UPPER MISSISSIPPI VALLEY INTO THE MID MISSOURI VALLEY/CENTRAL PLAINS AND SOUTHERN HIGH PLAINS... ...SUMMARY... Scattered strong to severe storms are expected this afternoon and evening over parts of the Upper Mississippi Valley southwestward into the central/southern High Plains. Large hail and severe/damaging winds should be the main threats, but a few tornadoes may also occur. ...Upper Mississippi Valley into the Mid Missouri Valley/Central Plains and Southern High Plains... A pronounced upper trough will advance eastward across the northern Plains and Canadian Prairie provinces today, with multiple embedded mid-level perturbations forecast to move northeastward across the northern/central Plains and upper MS Valley through the period. At the surface, a 997 mb low currently over eastern SD will develop northeastward towards the MN Arrowhead through this evening. A secondary surface low should remain located over the southern/central High Plains. Between these two lows, a surface cold front will continue to progress east-southeastward this afternoon and evening. This boundary will be the primary focus for severe thunderstorms today. Based on latest guidance, the broad Slight Risk extending from the upper MS Valley into the mid MO Valley/central Plains and southern High Plains has generally been expanded to account for severe/damaging wind potential continuing into at least mid evening. Current expectations are for robust thunderstorms to develop by early afternoon across the upper MS Valley and mid MO Valley along/near the cold front. With a rather moist airmass in place across these regions based on latest surface observations and area 12Z soundings, moderate instability is expected to develop this afternoon, even though cloud cover may temper diurnal heating to some extent, especially in MN. The stronger mid-level southwesterly flow should tend to remain displaced to the cool side of the surface front. Still, sufficient deep-layer shear should exist to support a mix of multicells and supercells with this initial development. Given the linear forcing of the front, upscale growth into multiple bowing clusters is anticipated later this afternoon and continuing into the evening. Both large hail and severe/damaging winds appear possible, with a transition to a mainly damaging wind threat as clusters become dominant. Enough low-level shear may also support some threat for a few tornadoes, especially in MN with any supercell that can be maintained. Additional intense convective development is expected with southward extent into the central Plains along the front, perhaps delayed until a little later in the afternoon as stronger daytime heating will be needed to erode a cap/lingering MLCIN. Strong instability and deep-layer shear should be present over parts of western/central KS, where multiple supercells may develop near/east of the secondary surface low. Isolated very large hail may occur with this activity given the favorable environment and presence of steep mid-level lapse rates. A few tornadoes may also occur in a narrow corridor across southwest KS this evening if supercells can be maintained as low-level shear increases. Otherwise, severe/damaging winds (with perhaps some reaching 75-80 mph on an isolated basis) appear probable as convection likely grows upscale into a bowing cluster across central KS late this afternoon/early evening. Scattered thunderstorms may also develop across the southern High Plains (OK/TX Panhandle regions) along/east of a dryline. Severe wind gusts should be the main threat if this activity occurs, as the boundary layer is forecast to become very well mixed, with steep low-level lapse rates present. ...Lower Great Lakes/Upper Ohio Valley into the Northeast... Recent water vapor satellite and radar imagery show multiple widely dispersed thunderstorm clusters and remnant MCVs present across the lower Great Lakes into the Northeast. This activity is occurring on the western/northern periphery of a prominent upper ridge centered over the Mid-Atlantic States and Carolinas. Surface heating will aid ample destabilization this afternoon across a broad portion of the upper OH River Valley into upstate New York and northern New England. Isolated to widely scattered thunderstorms will once again develop and increase into the afternoon, influenced in some areas by the aforementioned MCVs. Localized downbursts with strong/damaging wind gusts will be possible through the diurnal heating cycle. Have maintained a broad Marginal Risk to account for this potential, as confidence in a more focused corridor of damaging wind potential remains low. ...Lower/Middle Texas Coast... Low-level easterly flow will gradually increase late tonight into early Wednesday morning as Potential Tropical Cyclone 1 develops and moves westward over the southwest Gulf, per latest NHC forecast. While instability should remain weak, with poor lapse rates aloft, strengthening low-level shear may support a low chance for a tornado with any low-topped cells that can approach/reach parts of the lower/middle TX Coast near the end of the Day 1 period. This threat should continue into the Day 2/Wednesday time frame. ..Gleason/Halbert/Lyons.. 06/18/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Tue Jun 18 2024 Valid 181630Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE UPPER MISSISSIPPI VALLEY INTO THE MID MISSOURI VALLEY/CENTRAL PLAINS AND SOUTHERN HIGH PLAINS... ...SUMMARY... Scattered strong to severe storms are expected this afternoon and evening over parts of the Upper Mississippi Valley southwestward into the central/southern High Plains. Large hail and severe/damaging winds should be the main threats, but a few tornadoes may also occur. ...Upper Mississippi Valley into the Mid Missouri Valley/Central Plains and Southern High Plains... A pronounced upper trough will advance eastward across the northern Plains and Canadian Prairie provinces today, with multiple embedded mid-level perturbations forecast to move northeastward across the northern/central Plains and upper MS Valley through the period. At the surface, a 997 mb low currently over eastern SD will develop northeastward towards the MN Arrowhead through this evening. A secondary surface low should remain located over the southern/central High Plains. Between these two lows, a surface cold front will continue to progress east-southeastward this afternoon and evening. This boundary will be the primary focus for severe thunderstorms today. Based on latest guidance, the broad Slight Risk extending from the upper MS Valley into the mid MO Valley/central Plains and southern High Plains has generally been expanded to account for severe/damaging wind potential continuing into at least mid evening. Current expectations are for robust thunderstorms to develop by early afternoon across the upper MS Valley and mid MO Valley along/near the cold front. With a rather moist airmass in place across these regions based on latest surface observations and area 12Z soundings, moderate instability is expected to develop this afternoon, even though cloud cover may temper diurnal heating to some extent, especially in MN. The stronger mid-level southwesterly flow should tend to remain displaced to the cool side of the surface front. Still, sufficient deep-layer shear should exist to support a mix of multicells and supercells with this initial development. Given the linear forcing of the front, upscale growth into multiple bowing clusters is anticipated later this afternoon and continuing into the evening. Both large hail and severe/damaging winds appear possible, with a transition to a mainly damaging wind threat as clusters become dominant. Enough low-level shear may also support some threat for a few tornadoes, especially in MN with any supercell that can be maintained. Additional intense convective development is expected with southward extent into the central Plains along the front, perhaps delayed until a little later in the afternoon as stronger daytime heating will be needed to erode a cap/lingering MLCIN. Strong instability and deep-layer shear should be present over parts of western/central KS, where multiple supercells may develop near/east of the secondary surface low. Isolated very large hail may occur with this activity given the favorable environment and presence of steep mid-level lapse rates. A few tornadoes may also occur in a narrow corridor across southwest KS this evening if supercells can be maintained as low-level shear increases. Otherwise, severe/damaging winds (with perhaps some reaching 75-80 mph on an isolated basis) appear probable as convection likely grows upscale into a bowing cluster across central KS late this afternoon/early evening. Scattered thunderstorms may also develop across the southern High Plains (OK/TX Panhandle regions) along/east of a dryline. Severe wind gusts should be the main threat if this activity occurs, as the boundary layer is forecast to become very well mixed, with steep low-level lapse rates present. ...Lower Great Lakes/Upper Ohio Valley into the Northeast... Recent water vapor satellite and radar imagery show multiple widely dispersed thunderstorm clusters and remnant MCVs present across the lower Great Lakes into the Northeast. This activity is occurring on the western/northern periphery of a prominent upper ridge centered over the Mid-Atlantic States and Carolinas. Surface heating will aid ample destabilization this afternoon across a broad portion of the upper OH River Valley into upstate New York and northern New England. Isolated to widely scattered thunderstorms will once again develop and increase into the afternoon, influenced in some areas by the aforementioned MCVs. Localized downbursts with strong/damaging wind gusts will be possible through the diurnal heating cycle. Have maintained a broad Marginal Risk to account for this potential, as confidence in a more focused corridor of damaging wind potential remains low. ...Lower/Middle Texas Coast... Low-level easterly flow will gradually increase late tonight into early Wednesday morning as Potential Tropical Cyclone 1 develops and moves westward over the southwest Gulf, per latest NHC forecast. While instability should remain weak, with poor lapse rates aloft, strengthening low-level shear may support a low chance for a tornado with any low-topped cells that can approach/reach parts of the lower/middle TX Coast near the end of the Day 1 period. This threat should continue into the Day 2/Wednesday time frame. ..Gleason/Halbert/Lyons.. 06/18/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Tue Jun 18 2024 Valid 181630Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE UPPER MISSISSIPPI VALLEY INTO THE MID MISSOURI VALLEY/CENTRAL PLAINS AND SOUTHERN HIGH PLAINS... ...SUMMARY... Scattered strong to severe storms are expected this afternoon and evening over parts of the Upper Mississippi Valley southwestward into the central/southern High Plains. Large hail and severe/damaging winds should be the main threats, but a few tornadoes may also occur. ...Upper Mississippi Valley into the Mid Missouri Valley/Central Plains and Southern High Plains... A pronounced upper trough will advance eastward across the northern Plains and Canadian Prairie provinces today, with multiple embedded mid-level perturbations forecast to move northeastward across the northern/central Plains and upper MS Valley through the period. At the surface, a 997 mb low currently over eastern SD will develop northeastward towards the MN Arrowhead through this evening. A secondary surface low should remain located over the southern/central High Plains. Between these two lows, a surface cold front will continue to progress east-southeastward this afternoon and evening. This boundary will be the primary focus for severe thunderstorms today. Based on latest guidance, the broad Slight Risk extending from the upper MS Valley into the mid MO Valley/central Plains and southern High Plains has generally been expanded to account for severe/damaging wind potential continuing into at least mid evening. Current expectations are for robust thunderstorms to develop by early afternoon across the upper MS Valley and mid MO Valley along/near the cold front. With a rather moist airmass in place across these regions based on latest surface observations and area 12Z soundings, moderate instability is expected to develop this afternoon, even though cloud cover may temper diurnal heating to some extent, especially in MN. The stronger mid-level southwesterly flow should tend to remain displaced to the cool side of the surface front. Still, sufficient deep-layer shear should exist to support a mix of multicells and supercells with this initial development. Given the linear forcing of the front, upscale growth into multiple bowing clusters is anticipated later this afternoon and continuing into the evening. Both large hail and severe/damaging winds appear possible, with a transition to a mainly damaging wind threat as clusters become dominant. Enough low-level shear may also support some threat for a few tornadoes, especially in MN with any supercell that can be maintained. Additional intense convective development is expected with southward extent into the central Plains along the front, perhaps delayed until a little later in the afternoon as stronger daytime heating will be needed to erode a cap/lingering MLCIN. Strong instability and deep-layer shear should be present over parts of western/central KS, where multiple supercells may develop near/east of the secondary surface low. Isolated very large hail may occur with this activity given the favorable environment and presence of steep mid-level lapse rates. A few tornadoes may also occur in a narrow corridor across southwest KS this evening if supercells can be maintained as low-level shear increases. Otherwise, severe/damaging winds (with perhaps some reaching 75-80 mph on an isolated basis) appear probable as convection likely grows upscale into a bowing cluster across central KS late this afternoon/early evening. Scattered thunderstorms may also develop across the southern High Plains (OK/TX Panhandle regions) along/east of a dryline. Severe wind gusts should be the main threat if this activity occurs, as the boundary layer is forecast to become very well mixed, with steep low-level lapse rates present. ...Lower Great Lakes/Upper Ohio Valley into the Northeast... Recent water vapor satellite and radar imagery show multiple widely dispersed thunderstorm clusters and remnant MCVs present across the lower Great Lakes into the Northeast. This activity is occurring on the western/northern periphery of a prominent upper ridge centered over the Mid-Atlantic States and Carolinas. Surface heating will aid ample destabilization this afternoon across a broad portion of the upper OH River Valley into upstate New York and northern New England. Isolated to widely scattered thunderstorms will once again develop and increase into the afternoon, influenced in some areas by the aforementioned MCVs. Localized downbursts with strong/damaging wind gusts will be possible through the diurnal heating cycle. Have maintained a broad Marginal Risk to account for this potential, as confidence in a more focused corridor of damaging wind potential remains low. ...Lower/Middle Texas Coast... Low-level easterly flow will gradually increase late tonight into early Wednesday morning as Potential Tropical Cyclone 1 develops and moves westward over the southwest Gulf, per latest NHC forecast. While instability should remain weak, with poor lapse rates aloft, strengthening low-level shear may support a low chance for a tornado with any low-topped cells that can approach/reach parts of the lower/middle TX Coast near the end of the Day 1 period. This threat should continue into the Day 2/Wednesday time frame. ..Gleason/Halbert/Lyons.. 06/18/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Tue Jun 18 2024 Valid 181630Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE UPPER MISSISSIPPI VALLEY INTO THE MID MISSOURI VALLEY/CENTRAL PLAINS AND SOUTHERN HIGH PLAINS... ...SUMMARY... Scattered strong to severe storms are expected this afternoon and evening over parts of the Upper Mississippi Valley southwestward into the central/southern High Plains. Large hail and severe/damaging winds should be the main threats, but a few tornadoes may also occur. ...Upper Mississippi Valley into the Mid Missouri Valley/Central Plains and Southern High Plains... A pronounced upper trough will advance eastward across the northern Plains and Canadian Prairie provinces today, with multiple embedded mid-level perturbations forecast to move northeastward across the northern/central Plains and upper MS Valley through the period. At the surface, a 997 mb low currently over eastern SD will develop northeastward towards the MN Arrowhead through this evening. A secondary surface low should remain located over the southern/central High Plains. Between these two lows, a surface cold front will continue to progress east-southeastward this afternoon and evening. This boundary will be the primary focus for severe thunderstorms today. Based on latest guidance, the broad Slight Risk extending from the upper MS Valley into the mid MO Valley/central Plains and southern High Plains has generally been expanded to account for severe/damaging wind potential continuing into at least mid evening. Current expectations are for robust thunderstorms to develop by early afternoon across the upper MS Valley and mid MO Valley along/near the cold front. With a rather moist airmass in place across these regions based on latest surface observations and area 12Z soundings, moderate instability is expected to develop this afternoon, even though cloud cover may temper diurnal heating to some extent, especially in MN. The stronger mid-level southwesterly flow should tend to remain displaced to the cool side of the surface front. Still, sufficient deep-layer shear should exist to support a mix of multicells and supercells with this initial development. Given the linear forcing of the front, upscale growth into multiple bowing clusters is anticipated later this afternoon and continuing into the evening. Both large hail and severe/damaging winds appear possible, with a transition to a mainly damaging wind threat as clusters become dominant. Enough low-level shear may also support some threat for a few tornadoes, especially in MN with any supercell that can be maintained. Additional intense convective development is expected with southward extent into the central Plains along the front, perhaps delayed until a little later in the afternoon as stronger daytime heating will be needed to erode a cap/lingering MLCIN. Strong instability and deep-layer shear should be present over parts of western/central KS, where multiple supercells may develop near/east of the secondary surface low. Isolated very large hail may occur with this activity given the favorable environment and presence of steep mid-level lapse rates. A few tornadoes may also occur in a narrow corridor across southwest KS this evening if supercells can be maintained as low-level shear increases. Otherwise, severe/damaging winds (with perhaps some reaching 75-80 mph on an isolated basis) appear probable as convection likely grows upscale into a bowing cluster across central KS late this afternoon/early evening. Scattered thunderstorms may also develop across the southern High Plains (OK/TX Panhandle regions) along/east of a dryline. Severe wind gusts should be the main threat if this activity occurs, as the boundary layer is forecast to become very well mixed, with steep low-level lapse rates present. ...Lower Great Lakes/Upper Ohio Valley into the Northeast... Recent water vapor satellite and radar imagery show multiple widely dispersed thunderstorm clusters and remnant MCVs present across the lower Great Lakes into the Northeast. This activity is occurring on the western/northern periphery of a prominent upper ridge centered over the Mid-Atlantic States and Carolinas. Surface heating will aid ample destabilization this afternoon across a broad portion of the upper OH River Valley into upstate New York and northern New England. Isolated to widely scattered thunderstorms will once again develop and increase into the afternoon, influenced in some areas by the aforementioned MCVs. Localized downbursts with strong/damaging wind gusts will be possible through the diurnal heating cycle. Have maintained a broad Marginal Risk to account for this potential, as confidence in a more focused corridor of damaging wind potential remains low. ...Lower/Middle Texas Coast... Low-level easterly flow will gradually increase late tonight into early Wednesday morning as Potential Tropical Cyclone 1 develops and moves westward over the southwest Gulf, per latest NHC forecast. While instability should remain weak, with poor lapse rates aloft, strengthening low-level shear may support a low chance for a tornado with any low-topped cells that can approach/reach parts of the lower/middle TX Coast near the end of the Day 1 period. This threat should continue into the Day 2/Wednesday time frame. ..Gleason/Halbert/Lyons.. 06/18/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Tue Jun 18 2024 Valid 181630Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE UPPER MISSISSIPPI VALLEY INTO THE MID MISSOURI VALLEY/CENTRAL PLAINS AND SOUTHERN HIGH PLAINS... ...SUMMARY... Scattered strong to severe storms are expected this afternoon and evening over parts of the Upper Mississippi Valley southwestward into the central/southern High Plains. Large hail and severe/damaging winds should be the main threats, but a few tornadoes may also occur. ...Upper Mississippi Valley into the Mid Missouri Valley/Central Plains and Southern High Plains... A pronounced upper trough will advance eastward across the northern Plains and Canadian Prairie provinces today, with multiple embedded mid-level perturbations forecast to move northeastward across the northern/central Plains and upper MS Valley through the period. At the surface, a 997 mb low currently over eastern SD will develop northeastward towards the MN Arrowhead through this evening. A secondary surface low should remain located over the southern/central High Plains. Between these two lows, a surface cold front will continue to progress east-southeastward this afternoon and evening. This boundary will be the primary focus for severe thunderstorms today. Based on latest guidance, the broad Slight Risk extending from the upper MS Valley into the mid MO Valley/central Plains and southern High Plains has generally been expanded to account for severe/damaging wind potential continuing into at least mid evening. Current expectations are for robust thunderstorms to develop by early afternoon across the upper MS Valley and mid MO Valley along/near the cold front. With a rather moist airmass in place across these regions based on latest surface observations and area 12Z soundings, moderate instability is expected to develop this afternoon, even though cloud cover may temper diurnal heating to some extent, especially in MN. The stronger mid-level southwesterly flow should tend to remain displaced to the cool side of the surface front. Still, sufficient deep-layer shear should exist to support a mix of multicells and supercells with this initial development. Given the linear forcing of the front, upscale growth into multiple bowing clusters is anticipated later this afternoon and continuing into the evening. Both large hail and severe/damaging winds appear possible, with a transition to a mainly damaging wind threat as clusters become dominant. Enough low-level shear may also support some threat for a few tornadoes, especially in MN with any supercell that can be maintained. Additional intense convective development is expected with southward extent into the central Plains along the front, perhaps delayed until a little later in the afternoon as stronger daytime heating will be needed to erode a cap/lingering MLCIN. Strong instability and deep-layer shear should be present over parts of western/central KS, where multiple supercells may develop near/east of the secondary surface low. Isolated very large hail may occur with this activity given the favorable environment and presence of steep mid-level lapse rates. A few tornadoes may also occur in a narrow corridor across southwest KS this evening if supercells can be maintained as low-level shear increases. Otherwise, severe/damaging winds (with perhaps some reaching 75-80 mph on an isolated basis) appear probable as convection likely grows upscale into a bowing cluster across central KS late this afternoon/early evening. Scattered thunderstorms may also develop across the southern High Plains (OK/TX Panhandle regions) along/east of a dryline. Severe wind gusts should be the main threat if this activity occurs, as the boundary layer is forecast to become very well mixed, with steep low-level lapse rates present. ...Lower Great Lakes/Upper Ohio Valley into the Northeast... Recent water vapor satellite and radar imagery show multiple widely dispersed thunderstorm clusters and remnant MCVs present across the lower Great Lakes into the Northeast. This activity is occurring on the western/northern periphery of a prominent upper ridge centered over the Mid-Atlantic States and Carolinas. Surface heating will aid ample destabilization this afternoon across a broad portion of the upper OH River Valley into upstate New York and northern New England. Isolated to widely scattered thunderstorms will once again develop and increase into the afternoon, influenced in some areas by the aforementioned MCVs. Localized downbursts with strong/damaging wind gusts will be possible through the diurnal heating cycle. Have maintained a broad Marginal Risk to account for this potential, as confidence in a more focused corridor of damaging wind potential remains low. ...Lower/Middle Texas Coast... Low-level easterly flow will gradually increase late tonight into early Wednesday morning as Potential Tropical Cyclone 1 develops and moves westward over the southwest Gulf, per latest NHC forecast. While instability should remain weak, with poor lapse rates aloft, strengthening low-level shear may support a low chance for a tornado with any low-topped cells that can approach/reach parts of the lower/middle TX Coast near the end of the Day 1 period. This threat should continue into the Day 2/Wednesday time frame. ..Gleason/Halbert/Lyons.. 06/18/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Tue Jun 18 2024 Valid 181700Z - 191200Z ...Update... Only minor adjustments were made to the current Elevated area across eastern and southern NM. West to southwest sustained winds will increase late this morning through this afternoon near and east of the Sacramento Mountains, northeastward through the high plains of NM and the far western panhandles of TX/OK. The latest observational trends and high resolution NWP guidance suggest locally critical meteorological conditions may develop for 2-3 hours across far northeastern NM late this afternoon ahead of a stalling cold front. Less receptive fuels within this region preclude the need for a Critical area though. Much farther west across the Mohave Valley near the NV/AZ/CA borders, a very tight pressure gradient will continue to result in breezy north winds (gusts near 35-45 mph) behind a cold front, where RH is currently below 15 percent. However, wind speeds should quickly decrease after 18Z as a locally enhanced pressure gradient relaxes. ..Barnes.. 06/18/2024 .PREV DISCUSSION... /ISSUED 0152 AM CDT Tue Jun 18 2024/ ...Synopsis... A trough will lift northward across the Northern Rockies into the northern Plains today. Heights will rise across the southwestern US with weakening southwest gradients and lighter winds returning where the driest fuels remain currently. Areas of dry southwesterly flow will linger across portions of central/eastern New Mexico, with afternoon relative humidity reductions to 10-15 percent overlapping winds around 15 mph for a period of Elevated fire weather this afternoon. Localized breezes and Elevated fire weather concerns may extend further southwest into western New Mexico and southern Arizona. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Tue Jun 18 2024 Valid 181700Z - 191200Z ...Update... Only minor adjustments were made to the current Elevated area across eastern and southern NM. West to southwest sustained winds will increase late this morning through this afternoon near and east of the Sacramento Mountains, northeastward through the high plains of NM and the far western panhandles of TX/OK. The latest observational trends and high resolution NWP guidance suggest locally critical meteorological conditions may develop for 2-3 hours across far northeastern NM late this afternoon ahead of a stalling cold front. Less receptive fuels within this region preclude the need for a Critical area though. Much farther west across the Mohave Valley near the NV/AZ/CA borders, a very tight pressure gradient will continue to result in breezy north winds (gusts near 35-45 mph) behind a cold front, where RH is currently below 15 percent. However, wind speeds should quickly decrease after 18Z as a locally enhanced pressure gradient relaxes. ..Barnes.. 06/18/2024 .PREV DISCUSSION... /ISSUED 0152 AM CDT Tue Jun 18 2024/ ...Synopsis... A trough will lift northward across the Northern Rockies into the northern Plains today. Heights will rise across the southwestern US with weakening southwest gradients and lighter winds returning where the driest fuels remain currently. Areas of dry southwesterly flow will linger across portions of central/eastern New Mexico, with afternoon relative humidity reductions to 10-15 percent overlapping winds around 15 mph for a period of Elevated fire weather this afternoon. Localized breezes and Elevated fire weather concerns may extend further southwest into western New Mexico and southern Arizona. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Tue Jun 18 2024 Valid 181700Z - 191200Z ...Update... Only minor adjustments were made to the current Elevated area across eastern and southern NM. West to southwest sustained winds will increase late this morning through this afternoon near and east of the Sacramento Mountains, northeastward through the high plains of NM and the far western panhandles of TX/OK. The latest observational trends and high resolution NWP guidance suggest locally critical meteorological conditions may develop for 2-3 hours across far northeastern NM late this afternoon ahead of a stalling cold front. Less receptive fuels within this region preclude the need for a Critical area though. Much farther west across the Mohave Valley near the NV/AZ/CA borders, a very tight pressure gradient will continue to result in breezy north winds (gusts near 35-45 mph) behind a cold front, where RH is currently below 15 percent. However, wind speeds should quickly decrease after 18Z as a locally enhanced pressure gradient relaxes. ..Barnes.. 06/18/2024 .PREV DISCUSSION... /ISSUED 0152 AM CDT Tue Jun 18 2024/ ...Synopsis... A trough will lift northward across the Northern Rockies into the northern Plains today. Heights will rise across the southwestern US with weakening southwest gradients and lighter winds returning where the driest fuels remain currently. Areas of dry southwesterly flow will linger across portions of central/eastern New Mexico, with afternoon relative humidity reductions to 10-15 percent overlapping winds around 15 mph for a period of Elevated fire weather this afternoon. Localized breezes and Elevated fire weather concerns may extend further southwest into western New Mexico and southern Arizona. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Tue Jun 18 2024 Valid 181700Z - 191200Z ...Update... Only minor adjustments were made to the current Elevated area across eastern and southern NM. West to southwest sustained winds will increase late this morning through this afternoon near and east of the Sacramento Mountains, northeastward through the high plains of NM and the far western panhandles of TX/OK. The latest observational trends and high resolution NWP guidance suggest locally critical meteorological conditions may develop for 2-3 hours across far northeastern NM late this afternoon ahead of a stalling cold front. Less receptive fuels within this region preclude the need for a Critical area though. Much farther west across the Mohave Valley near the NV/AZ/CA borders, a very tight pressure gradient will continue to result in breezy north winds (gusts near 35-45 mph) behind a cold front, where RH is currently below 15 percent. However, wind speeds should quickly decrease after 18Z as a locally enhanced pressure gradient relaxes. ..Barnes.. 06/18/2024 .PREV DISCUSSION... /ISSUED 0152 AM CDT Tue Jun 18 2024/ ...Synopsis... A trough will lift northward across the Northern Rockies into the northern Plains today. Heights will rise across the southwestern US with weakening southwest gradients and lighter winds returning where the driest fuels remain currently. Areas of dry southwesterly flow will linger across portions of central/eastern New Mexico, with afternoon relative humidity reductions to 10-15 percent overlapping winds around 15 mph for a period of Elevated fire weather this afternoon. Localized breezes and Elevated fire weather concerns may extend further southwest into western New Mexico and southern Arizona. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Tue Jun 18 2024 Valid 181700Z - 191200Z ...Update... Only minor adjustments were made to the current Elevated area across eastern and southern NM. West to southwest sustained winds will increase late this morning through this afternoon near and east of the Sacramento Mountains, northeastward through the high plains of NM and the far western panhandles of TX/OK. The latest observational trends and high resolution NWP guidance suggest locally critical meteorological conditions may develop for 2-3 hours across far northeastern NM late this afternoon ahead of a stalling cold front. Less receptive fuels within this region preclude the need for a Critical area though. Much farther west across the Mohave Valley near the NV/AZ/CA borders, a very tight pressure gradient will continue to result in breezy north winds (gusts near 35-45 mph) behind a cold front, where RH is currently below 15 percent. However, wind speeds should quickly decrease after 18Z as a locally enhanced pressure gradient relaxes. ..Barnes.. 06/18/2024 .PREV DISCUSSION... /ISSUED 0152 AM CDT Tue Jun 18 2024/ ...Synopsis... A trough will lift northward across the Northern Rockies into the northern Plains today. Heights will rise across the southwestern US with weakening southwest gradients and lighter winds returning where the driest fuels remain currently. Areas of dry southwesterly flow will linger across portions of central/eastern New Mexico, with afternoon relative humidity reductions to 10-15 percent overlapping winds around 15 mph for a period of Elevated fire weather this afternoon. Localized breezes and Elevated fire weather concerns may extend further southwest into western New Mexico and southern Arizona. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Tue Jun 18 2024 Valid 181700Z - 191200Z ...Update... Only minor adjustments were made to the current Elevated area across eastern and southern NM. West to southwest sustained winds will increase late this morning through this afternoon near and east of the Sacramento Mountains, northeastward through the high plains of NM and the far western panhandles of TX/OK. The latest observational trends and high resolution NWP guidance suggest locally critical meteorological conditions may develop for 2-3 hours across far northeastern NM late this afternoon ahead of a stalling cold front. Less receptive fuels within this region preclude the need for a Critical area though. Much farther west across the Mohave Valley near the NV/AZ/CA borders, a very tight pressure gradient will continue to result in breezy north winds (gusts near 35-45 mph) behind a cold front, where RH is currently below 15 percent. However, wind speeds should quickly decrease after 18Z as a locally enhanced pressure gradient relaxes. ..Barnes.. 06/18/2024 .PREV DISCUSSION... /ISSUED 0152 AM CDT Tue Jun 18 2024/ ...Synopsis... A trough will lift northward across the Northern Rockies into the northern Plains today. Heights will rise across the southwestern US with weakening southwest gradients and lighter winds returning where the driest fuels remain currently. Areas of dry southwesterly flow will linger across portions of central/eastern New Mexico, with afternoon relative humidity reductions to 10-15 percent overlapping winds around 15 mph for a period of Elevated fire weather this afternoon. Localized breezes and Elevated fire weather concerns may extend further southwest into western New Mexico and southern Arizona. ...Please see www.spc.noaa.gov/fire for graphic product... Read more