Severe Storms

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0706 AM CDT Sat Jun 22 2024 Valid 221300Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST/GREAT LAKES... ...SUMMARY... Severe thunderstorms are possible this afternoon and evening across parts of the Midwest and Great Lakes region, including potential for damaging winds as well as a risk for tornadoes. ...Midwest/Upper Mississippi Valley and Upper Great Lakes... Ongoing scattered showers/thunderstorms near/south of the synoptic front complicates the later-day scenario to a degree, but outflow/air mass modification is expected into the afternoon with moderate to locally strong destabilization. This will be also coincident with a modestly amplifying shortwave trough/speed max over the Upper Mississippi Valley toward the Lake Michigan vicinity. This belt of 30-50 kt of west-southwesterly flow in the 850-500 mb layer is expected to overspread a destabilizing environment, with stronger insolation/destabilization most probable across eastern Iowa into northern Illinois by mid/late afternoon. Surface-based severe storm development including supercells will become probable by mid/late afternoon in vicinity of the modestly deepening surface low and triple point, including parts of northeast/east-central Iowa into far southern Wisconsin and northern Illinois. These storms will pose a tornado risk aside from more probable wind damage, which will increase as storms progress southeastward and also potentially expand southwestward somewhat along the southeastward-moving cold front this evening. ...Northern Mid-Atlantic States/Northeast... Deep-layer wind fields and shear are likely to remain weak, but moderately large CAPE (in excess of 2000 J/kg) may once again develop within weak surface troughing, along and southwest of the remnant surface frontal zone. It appears that this will become supportive of scattered strong thunderstorms with the potential to produce damaging wind gusts and possibly a few instances of hail. ...Northern Plains... Stronger mid/upper forcing for ascent and mid-level cooling are likely to remain north of the international border through and beyond peak daytime heating, but isolated severe storms could develop mainly across North Dakota by this evening, accompanied by a risk for marginally severe hail and/or wind. ...Southern Arizona... A few pulse-type strong/locally severe storms may occur this afternoon through early evening within a relatively moist and moderately environment across parts of south-central/southeast Arizona, with downbursts/strong wind gusts as the primary risk. ...Eastern Utah/western Colorado... While not expected to be nearly as active as Friday, a few strong storms could occur regionally, with strong wind gusts/some hail possible on a very isolated basis. ..Guyer/Mosier.. 06/22/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0706 AM CDT Sat Jun 22 2024 Valid 221300Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST/GREAT LAKES... ...SUMMARY... Severe thunderstorms are possible this afternoon and evening across parts of the Midwest and Great Lakes region, including potential for damaging winds as well as a risk for tornadoes. ...Midwest/Upper Mississippi Valley and Upper Great Lakes... Ongoing scattered showers/thunderstorms near/south of the synoptic front complicates the later-day scenario to a degree, but outflow/air mass modification is expected into the afternoon with moderate to locally strong destabilization. This will be also coincident with a modestly amplifying shortwave trough/speed max over the Upper Mississippi Valley toward the Lake Michigan vicinity. This belt of 30-50 kt of west-southwesterly flow in the 850-500 mb layer is expected to overspread a destabilizing environment, with stronger insolation/destabilization most probable across eastern Iowa into northern Illinois by mid/late afternoon. Surface-based severe storm development including supercells will become probable by mid/late afternoon in vicinity of the modestly deepening surface low and triple point, including parts of northeast/east-central Iowa into far southern Wisconsin and northern Illinois. These storms will pose a tornado risk aside from more probable wind damage, which will increase as storms progress southeastward and also potentially expand southwestward somewhat along the southeastward-moving cold front this evening. ...Northern Mid-Atlantic States/Northeast... Deep-layer wind fields and shear are likely to remain weak, but moderately large CAPE (in excess of 2000 J/kg) may once again develop within weak surface troughing, along and southwest of the remnant surface frontal zone. It appears that this will become supportive of scattered strong thunderstorms with the potential to produce damaging wind gusts and possibly a few instances of hail. ...Northern Plains... Stronger mid/upper forcing for ascent and mid-level cooling are likely to remain north of the international border through and beyond peak daytime heating, but isolated severe storms could develop mainly across North Dakota by this evening, accompanied by a risk for marginally severe hail and/or wind. ...Southern Arizona... A few pulse-type strong/locally severe storms may occur this afternoon through early evening within a relatively moist and moderately environment across parts of south-central/southeast Arizona, with downbursts/strong wind gusts as the primary risk. ...Eastern Utah/western Colorado... While not expected to be nearly as active as Friday, a few strong storms could occur regionally, with strong wind gusts/some hail possible on a very isolated basis. ..Guyer/Mosier.. 06/22/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0706 AM CDT Sat Jun 22 2024 Valid 221300Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST/GREAT LAKES... ...SUMMARY... Severe thunderstorms are possible this afternoon and evening across parts of the Midwest and Great Lakes region, including potential for damaging winds as well as a risk for tornadoes. ...Midwest/Upper Mississippi Valley and Upper Great Lakes... Ongoing scattered showers/thunderstorms near/south of the synoptic front complicates the later-day scenario to a degree, but outflow/air mass modification is expected into the afternoon with moderate to locally strong destabilization. This will be also coincident with a modestly amplifying shortwave trough/speed max over the Upper Mississippi Valley toward the Lake Michigan vicinity. This belt of 30-50 kt of west-southwesterly flow in the 850-500 mb layer is expected to overspread a destabilizing environment, with stronger insolation/destabilization most probable across eastern Iowa into northern Illinois by mid/late afternoon. Surface-based severe storm development including supercells will become probable by mid/late afternoon in vicinity of the modestly deepening surface low and triple point, including parts of northeast/east-central Iowa into far southern Wisconsin and northern Illinois. These storms will pose a tornado risk aside from more probable wind damage, which will increase as storms progress southeastward and also potentially expand southwestward somewhat along the southeastward-moving cold front this evening. ...Northern Mid-Atlantic States/Northeast... Deep-layer wind fields and shear are likely to remain weak, but moderately large CAPE (in excess of 2000 J/kg) may once again develop within weak surface troughing, along and southwest of the remnant surface frontal zone. It appears that this will become supportive of scattered strong thunderstorms with the potential to produce damaging wind gusts and possibly a few instances of hail. ...Northern Plains... Stronger mid/upper forcing for ascent and mid-level cooling are likely to remain north of the international border through and beyond peak daytime heating, but isolated severe storms could develop mainly across North Dakota by this evening, accompanied by a risk for marginally severe hail and/or wind. ...Southern Arizona... A few pulse-type strong/locally severe storms may occur this afternoon through early evening within a relatively moist and moderately environment across parts of south-central/southeast Arizona, with downbursts/strong wind gusts as the primary risk. ...Eastern Utah/western Colorado... While not expected to be nearly as active as Friday, a few strong storms could occur regionally, with strong wind gusts/some hail possible on a very isolated basis. ..Guyer/Mosier.. 06/22/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0706 AM CDT Sat Jun 22 2024 Valid 221300Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST/GREAT LAKES... ...SUMMARY... Severe thunderstorms are possible this afternoon and evening across parts of the Midwest and Great Lakes region, including potential for damaging winds as well as a risk for tornadoes. ...Midwest/Upper Mississippi Valley and Upper Great Lakes... Ongoing scattered showers/thunderstorms near/south of the synoptic front complicates the later-day scenario to a degree, but outflow/air mass modification is expected into the afternoon with moderate to locally strong destabilization. This will be also coincident with a modestly amplifying shortwave trough/speed max over the Upper Mississippi Valley toward the Lake Michigan vicinity. This belt of 30-50 kt of west-southwesterly flow in the 850-500 mb layer is expected to overspread a destabilizing environment, with stronger insolation/destabilization most probable across eastern Iowa into northern Illinois by mid/late afternoon. Surface-based severe storm development including supercells will become probable by mid/late afternoon in vicinity of the modestly deepening surface low and triple point, including parts of northeast/east-central Iowa into far southern Wisconsin and northern Illinois. These storms will pose a tornado risk aside from more probable wind damage, which will increase as storms progress southeastward and also potentially expand southwestward somewhat along the southeastward-moving cold front this evening. ...Northern Mid-Atlantic States/Northeast... Deep-layer wind fields and shear are likely to remain weak, but moderately large CAPE (in excess of 2000 J/kg) may once again develop within weak surface troughing, along and southwest of the remnant surface frontal zone. It appears that this will become supportive of scattered strong thunderstorms with the potential to produce damaging wind gusts and possibly a few instances of hail. ...Northern Plains... Stronger mid/upper forcing for ascent and mid-level cooling are likely to remain north of the international border through and beyond peak daytime heating, but isolated severe storms could develop mainly across North Dakota by this evening, accompanied by a risk for marginally severe hail and/or wind. ...Southern Arizona... A few pulse-type strong/locally severe storms may occur this afternoon through early evening within a relatively moist and moderately environment across parts of south-central/southeast Arizona, with downbursts/strong wind gusts as the primary risk. ...Eastern Utah/western Colorado... While not expected to be nearly as active as Friday, a few strong storms could occur regionally, with strong wind gusts/some hail possible on a very isolated basis. ..Guyer/Mosier.. 06/22/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0706 AM CDT Sat Jun 22 2024 Valid 221300Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST/GREAT LAKES... ...SUMMARY... Severe thunderstorms are possible this afternoon and evening across parts of the Midwest and Great Lakes region, including potential for damaging winds as well as a risk for tornadoes. ...Midwest/Upper Mississippi Valley and Upper Great Lakes... Ongoing scattered showers/thunderstorms near/south of the synoptic front complicates the later-day scenario to a degree, but outflow/air mass modification is expected into the afternoon with moderate to locally strong destabilization. This will be also coincident with a modestly amplifying shortwave trough/speed max over the Upper Mississippi Valley toward the Lake Michigan vicinity. This belt of 30-50 kt of west-southwesterly flow in the 850-500 mb layer is expected to overspread a destabilizing environment, with stronger insolation/destabilization most probable across eastern Iowa into northern Illinois by mid/late afternoon. Surface-based severe storm development including supercells will become probable by mid/late afternoon in vicinity of the modestly deepening surface low and triple point, including parts of northeast/east-central Iowa into far southern Wisconsin and northern Illinois. These storms will pose a tornado risk aside from more probable wind damage, which will increase as storms progress southeastward and also potentially expand southwestward somewhat along the southeastward-moving cold front this evening. ...Northern Mid-Atlantic States/Northeast... Deep-layer wind fields and shear are likely to remain weak, but moderately large CAPE (in excess of 2000 J/kg) may once again develop within weak surface troughing, along and southwest of the remnant surface frontal zone. It appears that this will become supportive of scattered strong thunderstorms with the potential to produce damaging wind gusts and possibly a few instances of hail. ...Northern Plains... Stronger mid/upper forcing for ascent and mid-level cooling are likely to remain north of the international border through and beyond peak daytime heating, but isolated severe storms could develop mainly across North Dakota by this evening, accompanied by a risk for marginally severe hail and/or wind. ...Southern Arizona... A few pulse-type strong/locally severe storms may occur this afternoon through early evening within a relatively moist and moderately environment across parts of south-central/southeast Arizona, with downbursts/strong wind gusts as the primary risk. ...Eastern Utah/western Colorado... While not expected to be nearly as active as Friday, a few strong storms could occur regionally, with strong wind gusts/some hail possible on a very isolated basis. ..Guyer/Mosier.. 06/22/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0706 AM CDT Sat Jun 22 2024 Valid 221300Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MIDWEST/GREAT LAKES... ...SUMMARY... Severe thunderstorms are possible this afternoon and evening across parts of the Midwest and Great Lakes region, including potential for damaging winds as well as a risk for tornadoes. ...Midwest/Upper Mississippi Valley and Upper Great Lakes... Ongoing scattered showers/thunderstorms near/south of the synoptic front complicates the later-day scenario to a degree, but outflow/air mass modification is expected into the afternoon with moderate to locally strong destabilization. This will be also coincident with a modestly amplifying shortwave trough/speed max over the Upper Mississippi Valley toward the Lake Michigan vicinity. This belt of 30-50 kt of west-southwesterly flow in the 850-500 mb layer is expected to overspread a destabilizing environment, with stronger insolation/destabilization most probable across eastern Iowa into northern Illinois by mid/late afternoon. Surface-based severe storm development including supercells will become probable by mid/late afternoon in vicinity of the modestly deepening surface low and triple point, including parts of northeast/east-central Iowa into far southern Wisconsin and northern Illinois. These storms will pose a tornado risk aside from more probable wind damage, which will increase as storms progress southeastward and also potentially expand southwestward somewhat along the southeastward-moving cold front this evening. ...Northern Mid-Atlantic States/Northeast... Deep-layer wind fields and shear are likely to remain weak, but moderately large CAPE (in excess of 2000 J/kg) may once again develop within weak surface troughing, along and southwest of the remnant surface frontal zone. It appears that this will become supportive of scattered strong thunderstorms with the potential to produce damaging wind gusts and possibly a few instances of hail. ...Northern Plains... Stronger mid/upper forcing for ascent and mid-level cooling are likely to remain north of the international border through and beyond peak daytime heating, but isolated severe storms could develop mainly across North Dakota by this evening, accompanied by a risk for marginally severe hail and/or wind. ...Southern Arizona... A few pulse-type strong/locally severe storms may occur this afternoon through early evening within a relatively moist and moderately environment across parts of south-central/southeast Arizona, with downbursts/strong wind gusts as the primary risk. ...Eastern Utah/western Colorado... While not expected to be nearly as active as Friday, a few strong storms could occur regionally, with strong wind gusts/some hail possible on a very isolated basis. ..Guyer/Mosier.. 06/22/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0312 AM CDT Sat Jun 22 2024 Valid 251200Z - 301200Z ...DISCUSSION... ...D4/Tuesday: Central Great Plains into the upper Midwest... Some severe-thunderstorm potential may evolve from the central Great Plains into the upper Midwest on Tuesday, along/ahead of a southward-moving cold front. Uncertainty remains regarding storm evolution leading into this period from D3/Monday, with some potential for the cold front to become increasingly displaced from stronger flow aloft. However, moderate to strong buoyancy and at least modest deep-layer shear could support strong to severe storms Tuesday afternoon/evening. ...D5/Wednesday: Central/southern Great Plains into the OH Valley and Northeast... Some threat for strong to severe storms will again be possible near the cold front Wednesday afternoon and evening, which is generally forecast to be draped from the south-central Great Plains northeastward across the OH Valley into parts of the Northeast. There is some potential for a stronger mid/upper-level shortwave trough to interact with the front across the Northeast, though instability may remain somewhat limited. Farther southwest into the Plains, pre-frontal instability will be greater, but deep-layer shear is expected to remain rather weak. ...D6/Thursday - D8/Saturday... Extended-range guidance generally supports potential for a mid/upper-level shortwave trough to amplify and move across the northern CONUS by the end of next week, though there is considerable spread regarding the timing of any such shortwave. While predictability is too low to introduce probabilities at this time, there is potential for an organized severe-thunderstorm threat to evolve somewhere from the northern Plains into the Great Lakes and Northeast, during the Thursday to Saturday time frame. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0312 AM CDT Sat Jun 22 2024 Valid 251200Z - 301200Z ...DISCUSSION... ...D4/Tuesday: Central Great Plains into the upper Midwest... Some severe-thunderstorm potential may evolve from the central Great Plains into the upper Midwest on Tuesday, along/ahead of a southward-moving cold front. Uncertainty remains regarding storm evolution leading into this period from D3/Monday, with some potential for the cold front to become increasingly displaced from stronger flow aloft. However, moderate to strong buoyancy and at least modest deep-layer shear could support strong to severe storms Tuesday afternoon/evening. ...D5/Wednesday: Central/southern Great Plains into the OH Valley and Northeast... Some threat for strong to severe storms will again be possible near the cold front Wednesday afternoon and evening, which is generally forecast to be draped from the south-central Great Plains northeastward across the OH Valley into parts of the Northeast. There is some potential for a stronger mid/upper-level shortwave trough to interact with the front across the Northeast, though instability may remain somewhat limited. Farther southwest into the Plains, pre-frontal instability will be greater, but deep-layer shear is expected to remain rather weak. ...D6/Thursday - D8/Saturday... Extended-range guidance generally supports potential for a mid/upper-level shortwave trough to amplify and move across the northern CONUS by the end of next week, though there is considerable spread regarding the timing of any such shortwave. While predictability is too low to introduce probabilities at this time, there is potential for an organized severe-thunderstorm threat to evolve somewhere from the northern Plains into the Great Lakes and Northeast, during the Thursday to Saturday time frame. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0312 AM CDT Sat Jun 22 2024 Valid 251200Z - 301200Z ...DISCUSSION... ...D4/Tuesday: Central Great Plains into the upper Midwest... Some severe-thunderstorm potential may evolve from the central Great Plains into the upper Midwest on Tuesday, along/ahead of a southward-moving cold front. Uncertainty remains regarding storm evolution leading into this period from D3/Monday, with some potential for the cold front to become increasingly displaced from stronger flow aloft. However, moderate to strong buoyancy and at least modest deep-layer shear could support strong to severe storms Tuesday afternoon/evening. ...D5/Wednesday: Central/southern Great Plains into the OH Valley and Northeast... Some threat for strong to severe storms will again be possible near the cold front Wednesday afternoon and evening, which is generally forecast to be draped from the south-central Great Plains northeastward across the OH Valley into parts of the Northeast. There is some potential for a stronger mid/upper-level shortwave trough to interact with the front across the Northeast, though instability may remain somewhat limited. Farther southwest into the Plains, pre-frontal instability will be greater, but deep-layer shear is expected to remain rather weak. ...D6/Thursday - D8/Saturday... Extended-range guidance generally supports potential for a mid/upper-level shortwave trough to amplify and move across the northern CONUS by the end of next week, though there is considerable spread regarding the timing of any such shortwave. While predictability is too low to introduce probabilities at this time, there is potential for an organized severe-thunderstorm threat to evolve somewhere from the northern Plains into the Great Lakes and Northeast, during the Thursday to Saturday time frame. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0312 AM CDT Sat Jun 22 2024 Valid 251200Z - 301200Z ...DISCUSSION... ...D4/Tuesday: Central Great Plains into the upper Midwest... Some severe-thunderstorm potential may evolve from the central Great Plains into the upper Midwest on Tuesday, along/ahead of a southward-moving cold front. Uncertainty remains regarding storm evolution leading into this period from D3/Monday, with some potential for the cold front to become increasingly displaced from stronger flow aloft. However, moderate to strong buoyancy and at least modest deep-layer shear could support strong to severe storms Tuesday afternoon/evening. ...D5/Wednesday: Central/southern Great Plains into the OH Valley and Northeast... Some threat for strong to severe storms will again be possible near the cold front Wednesday afternoon and evening, which is generally forecast to be draped from the south-central Great Plains northeastward across the OH Valley into parts of the Northeast. There is some potential for a stronger mid/upper-level shortwave trough to interact with the front across the Northeast, though instability may remain somewhat limited. Farther southwest into the Plains, pre-frontal instability will be greater, but deep-layer shear is expected to remain rather weak. ...D6/Thursday - D8/Saturday... Extended-range guidance generally supports potential for a mid/upper-level shortwave trough to amplify and move across the northern CONUS by the end of next week, though there is considerable spread regarding the timing of any such shortwave. While predictability is too low to introduce probabilities at this time, there is potential for an organized severe-thunderstorm threat to evolve somewhere from the northern Plains into the Great Lakes and Northeast, during the Thursday to Saturday time frame. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Sat Jun 22 2024 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF MN...NORTHWEST WI...WESTERN UPPER MI... ...SUMMARY... Severe thunderstorms are possible on Monday across parts of the northern Great Plains into the upper Mississippi Valley and Great Lakes. ...Northern Great Plains into the upper MS Valley/Great Lakes... Uncertainty remains rather high regarding storm potential on Monday from the northern Great Plains into the upper MS Valley and Great Lakes. However, with some conditional significant-severe potential within a favorable environment, a Slight Risk has been added for parts of MN into northwest WI and western upper MI, where confidence is currently highest in isolated to widely scattered storm coverage. A mid/upper-level shortwave trough and related surface low are forecast to move eastward across parts of SK/MB on Monday. A secondary surface low is forecast to develop along a trailing surface trough/weak cold front across the Dakotas. A surface boundary initially draped roughly from the Ohio Valley northwestward through parts of IA and southeast SD is forecast to move northward as a warm front, potentially reaching parts of central MN and eastern ND by Monday evening. Storm development/evolution across the region remains unclear, with the stronger large-scale ascent expected to remain north of the international border. However, strong to locally extreme instability is expected to develop along/east of the surface trough across the Dakotas, and along and to the south/west of the northward moving warm front. While the warm sector may remain capped for much of the day, at least isolated storm development will be possible near the warm front, and also potentially near the surface trough/cold front. Elevated convection may also develop to the cool side of the warm front, especially during the evening when some intensification of a southwesterly low-level jet is expected. Deep-layer shear will be sufficient for organized convection. Any surface-based supercell development could pose a conditional risk of all severe hazards, including some potential for significant hail and/or wind given the very favorable thermodynamic environment. Depending on the evolution of initial storm development, an MCS could develop and move southeastward along the instability gradient, though this scenario remains rather uncertain at this time. ...Coastal Carolinas... Some guidance suggests a southeastward-moving cold front will slow down or stall across eastern NC/SC, resulting in the potential for scattered thunderstorm development during the afternoon, within a moderately unstable environment. Should this occur, modest northwesterly flow aloft could support sufficient storm organization for an isolated damaging wind and hail threat. This scenario remains uncertain, but severe probabilities may eventually be needed if confidence increases. ..Dean.. 06/22/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Sat Jun 22 2024 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF MN...NORTHWEST WI...WESTERN UPPER MI... ...SUMMARY... Severe thunderstorms are possible on Monday across parts of the northern Great Plains into the upper Mississippi Valley and Great Lakes. ...Northern Great Plains into the upper MS Valley/Great Lakes... Uncertainty remains rather high regarding storm potential on Monday from the northern Great Plains into the upper MS Valley and Great Lakes. However, with some conditional significant-severe potential within a favorable environment, a Slight Risk has been added for parts of MN into northwest WI and western upper MI, where confidence is currently highest in isolated to widely scattered storm coverage. A mid/upper-level shortwave trough and related surface low are forecast to move eastward across parts of SK/MB on Monday. A secondary surface low is forecast to develop along a trailing surface trough/weak cold front across the Dakotas. A surface boundary initially draped roughly from the Ohio Valley northwestward through parts of IA and southeast SD is forecast to move northward as a warm front, potentially reaching parts of central MN and eastern ND by Monday evening. Storm development/evolution across the region remains unclear, with the stronger large-scale ascent expected to remain north of the international border. However, strong to locally extreme instability is expected to develop along/east of the surface trough across the Dakotas, and along and to the south/west of the northward moving warm front. While the warm sector may remain capped for much of the day, at least isolated storm development will be possible near the warm front, and also potentially near the surface trough/cold front. Elevated convection may also develop to the cool side of the warm front, especially during the evening when some intensification of a southwesterly low-level jet is expected. Deep-layer shear will be sufficient for organized convection. Any surface-based supercell development could pose a conditional risk of all severe hazards, including some potential for significant hail and/or wind given the very favorable thermodynamic environment. Depending on the evolution of initial storm development, an MCS could develop and move southeastward along the instability gradient, though this scenario remains rather uncertain at this time. ...Coastal Carolinas... Some guidance suggests a southeastward-moving cold front will slow down or stall across eastern NC/SC, resulting in the potential for scattered thunderstorm development during the afternoon, within a moderately unstable environment. Should this occur, modest northwesterly flow aloft could support sufficient storm organization for an isolated damaging wind and hail threat. This scenario remains uncertain, but severe probabilities may eventually be needed if confidence increases. ..Dean.. 06/22/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Sat Jun 22 2024 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF MN...NORTHWEST WI...WESTERN UPPER MI... ...SUMMARY... Severe thunderstorms are possible on Monday across parts of the northern Great Plains into the upper Mississippi Valley and Great Lakes. ...Northern Great Plains into the upper MS Valley/Great Lakes... Uncertainty remains rather high regarding storm potential on Monday from the northern Great Plains into the upper MS Valley and Great Lakes. However, with some conditional significant-severe potential within a favorable environment, a Slight Risk has been added for parts of MN into northwest WI and western upper MI, where confidence is currently highest in isolated to widely scattered storm coverage. A mid/upper-level shortwave trough and related surface low are forecast to move eastward across parts of SK/MB on Monday. A secondary surface low is forecast to develop along a trailing surface trough/weak cold front across the Dakotas. A surface boundary initially draped roughly from the Ohio Valley northwestward through parts of IA and southeast SD is forecast to move northward as a warm front, potentially reaching parts of central MN and eastern ND by Monday evening. Storm development/evolution across the region remains unclear, with the stronger large-scale ascent expected to remain north of the international border. However, strong to locally extreme instability is expected to develop along/east of the surface trough across the Dakotas, and along and to the south/west of the northward moving warm front. While the warm sector may remain capped for much of the day, at least isolated storm development will be possible near the warm front, and also potentially near the surface trough/cold front. Elevated convection may also develop to the cool side of the warm front, especially during the evening when some intensification of a southwesterly low-level jet is expected. Deep-layer shear will be sufficient for organized convection. Any surface-based supercell development could pose a conditional risk of all severe hazards, including some potential for significant hail and/or wind given the very favorable thermodynamic environment. Depending on the evolution of initial storm development, an MCS could develop and move southeastward along the instability gradient, though this scenario remains rather uncertain at this time. ...Coastal Carolinas... Some guidance suggests a southeastward-moving cold front will slow down or stall across eastern NC/SC, resulting in the potential for scattered thunderstorm development during the afternoon, within a moderately unstable environment. Should this occur, modest northwesterly flow aloft could support sufficient storm organization for an isolated damaging wind and hail threat. This scenario remains uncertain, but severe probabilities may eventually be needed if confidence increases. ..Dean.. 06/22/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Sat Jun 22 2024 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF MN...NORTHWEST WI...WESTERN UPPER MI... ...SUMMARY... Severe thunderstorms are possible on Monday across parts of the northern Great Plains into the upper Mississippi Valley and Great Lakes. ...Northern Great Plains into the upper MS Valley/Great Lakes... Uncertainty remains rather high regarding storm potential on Monday from the northern Great Plains into the upper MS Valley and Great Lakes. However, with some conditional significant-severe potential within a favorable environment, a Slight Risk has been added for parts of MN into northwest WI and western upper MI, where confidence is currently highest in isolated to widely scattered storm coverage. A mid/upper-level shortwave trough and related surface low are forecast to move eastward across parts of SK/MB on Monday. A secondary surface low is forecast to develop along a trailing surface trough/weak cold front across the Dakotas. A surface boundary initially draped roughly from the Ohio Valley northwestward through parts of IA and southeast SD is forecast to move northward as a warm front, potentially reaching parts of central MN and eastern ND by Monday evening. Storm development/evolution across the region remains unclear, with the stronger large-scale ascent expected to remain north of the international border. However, strong to locally extreme instability is expected to develop along/east of the surface trough across the Dakotas, and along and to the south/west of the northward moving warm front. While the warm sector may remain capped for much of the day, at least isolated storm development will be possible near the warm front, and also potentially near the surface trough/cold front. Elevated convection may also develop to the cool side of the warm front, especially during the evening when some intensification of a southwesterly low-level jet is expected. Deep-layer shear will be sufficient for organized convection. Any surface-based supercell development could pose a conditional risk of all severe hazards, including some potential for significant hail and/or wind given the very favorable thermodynamic environment. Depending on the evolution of initial storm development, an MCS could develop and move southeastward along the instability gradient, though this scenario remains rather uncertain at this time. ...Coastal Carolinas... Some guidance suggests a southeastward-moving cold front will slow down or stall across eastern NC/SC, resulting in the potential for scattered thunderstorm development during the afternoon, within a moderately unstable environment. Should this occur, modest northwesterly flow aloft could support sufficient storm organization for an isolated damaging wind and hail threat. This scenario remains uncertain, but severe probabilities may eventually be needed if confidence increases. ..Dean.. 06/22/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0101 AM CDT Sat Jun 22 2024 Valid 231200Z - 241200Z ...Synopsis... An upper-level trough will move through Washington during the afternoon. A strong pressure gradient will develop as a surface low deepens in the northern Rockies into Alberta/Saskatchewan. ...Northwest... Strong westerly surface winds across the Cascades will promote downslope drying into the Columbia Basin during the afternoon. Given some push of marine air to the east, it is possible that RH will not become overly low. However, generally dry fuels and 15-20 mph winds will support an elevated fire weather risk. ...OR/CA/NV... The surface pressure gradient and mid-level winds will be weaker than farther north, but confidence in RH of 10-20% is much higher. Winds could locally approach 20 mph, but will more broadly be around 15 mph. Locally elevated conditions are expected to the lee of the southern Cascades and northern Sierra. ...Snake River Plain... On the fringe of the strong mid-level winds, favorably oriented with the Valley, winds of 15-25 mph appear possible. RH of 15-20% can be expected during the afternoon. Though meteorological conditions could become critical, fuels are not sufficiently dry to support more than an elevated risk. ..Wendt.. 06/22/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0101 AM CDT Sat Jun 22 2024 Valid 231200Z - 241200Z ...Synopsis... An upper-level trough will move through Washington during the afternoon. A strong pressure gradient will develop as a surface low deepens in the northern Rockies into Alberta/Saskatchewan. ...Northwest... Strong westerly surface winds across the Cascades will promote downslope drying into the Columbia Basin during the afternoon. Given some push of marine air to the east, it is possible that RH will not become overly low. However, generally dry fuels and 15-20 mph winds will support an elevated fire weather risk. ...OR/CA/NV... The surface pressure gradient and mid-level winds will be weaker than farther north, but confidence in RH of 10-20% is much higher. Winds could locally approach 20 mph, but will more broadly be around 15 mph. Locally elevated conditions are expected to the lee of the southern Cascades and northern Sierra. ...Snake River Plain... On the fringe of the strong mid-level winds, favorably oriented with the Valley, winds of 15-25 mph appear possible. RH of 15-20% can be expected during the afternoon. Though meteorological conditions could become critical, fuels are not sufficiently dry to support more than an elevated risk. ..Wendt.. 06/22/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0101 AM CDT Sat Jun 22 2024 Valid 231200Z - 241200Z ...Synopsis... An upper-level trough will move through Washington during the afternoon. A strong pressure gradient will develop as a surface low deepens in the northern Rockies into Alberta/Saskatchewan. ...Northwest... Strong westerly surface winds across the Cascades will promote downslope drying into the Columbia Basin during the afternoon. Given some push of marine air to the east, it is possible that RH will not become overly low. However, generally dry fuels and 15-20 mph winds will support an elevated fire weather risk. ...OR/CA/NV... The surface pressure gradient and mid-level winds will be weaker than farther north, but confidence in RH of 10-20% is much higher. Winds could locally approach 20 mph, but will more broadly be around 15 mph. Locally elevated conditions are expected to the lee of the southern Cascades and northern Sierra. ...Snake River Plain... On the fringe of the strong mid-level winds, favorably oriented with the Valley, winds of 15-25 mph appear possible. RH of 15-20% can be expected during the afternoon. Though meteorological conditions could become critical, fuels are not sufficiently dry to support more than an elevated risk. ..Wendt.. 06/22/2024 ...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 0100 AM CDT Sat Jun 22 2024 Valid 221200Z - 231200Z ...NO CRITICAL AREAS... ...Synopsis... A flattened upper-level ridge will be situated across much of the southern CONUS today. With time, shortwave ridging will build over parts of the Great Basin into the Rockies. Stronger, zonal mid-level winds will exist within the northern portions of the CONUS. Late in the period, an upper-level trough will approach the Northwest. Dry and modestly breezy conditions are possible within parts of the Great Basin into a few areas east of the Cascades in the Northwest. Given weak large-scale features, winds will generally remain too light for more than locally elevated concerns. Cloud cover in the Northwest will also keep RH values somewhat marginal and any increase in winds will tend to be after peak heating. ..Wendt.. 06/22/2024 ...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 0100 AM CDT Sat Jun 22 2024 Valid 221200Z - 231200Z ...NO CRITICAL AREAS... ...Synopsis... A flattened upper-level ridge will be situated across much of the southern CONUS today. With time, shortwave ridging will build over parts of the Great Basin into the Rockies. Stronger, zonal mid-level winds will exist within the northern portions of the CONUS. Late in the period, an upper-level trough will approach the Northwest. Dry and modestly breezy conditions are possible within parts of the Great Basin into a few areas east of the Cascades in the Northwest. Given weak large-scale features, winds will generally remain too light for more than locally elevated concerns. Cloud cover in the Northwest will also keep RH values somewhat marginal and any increase in winds will tend to be after peak heating. ..Wendt.. 06/22/2024 ...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 0100 AM CDT Sat Jun 22 2024 Valid 221200Z - 231200Z ...NO CRITICAL AREAS... ...Synopsis... A flattened upper-level ridge will be situated across much of the southern CONUS today. With time, shortwave ridging will build over parts of the Great Basin into the Rockies. Stronger, zonal mid-level winds will exist within the northern portions of the CONUS. Late in the period, an upper-level trough will approach the Northwest. Dry and modestly breezy conditions are possible within parts of the Great Basin into a few areas east of the Cascades in the Northwest. Given weak large-scale features, winds will generally remain too light for more than locally elevated concerns. Cloud cover in the Northwest will also keep RH values somewhat marginal and any increase in winds will tend to be after peak heating. ..Wendt.. 06/22/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more