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SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sat Jun 21 2025 Valid 221200Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST INTO CENTRAL NE... ...SUMMARY... Severe thunderstorms are possible on Sunday from parts of the central and northern Plains into the upper Midwest. Significant hail and wind are possible across parts of eastern North Dakota and northern Minnesota, along with some tornado potential. ...Synopsis... A mid/upper-level low initially over ID is forecast to move northeastward as a shortwave trough Sunday, reaching parts of the northern Great Plains and Canadian Prairies by Sunday night. As this occurs, a surface low initially over parts of NE/SD will move toward northwest MN, as a trailing cold front moves across parts of the central/northern Plains and Upper Midwest. Farther east, a mid/upper-level shortwave trough and associated surface low and weak cold front will move across parts of New England. Guidance continues to vary regarding the timing and intensity of this system. In the wake of this shortwave trough, an upper ridge will amplify into parts of the Northeast. ...Great Plains into the Upper Midwest/Great Lakes... Strong to extreme instability will again develop from the central/northern Plains into the Upper Midwest and Great Lakes, along/ahead of the front. Stronger deep-layer flow and ascent will tend to lag behind the front, though sufficient vertical shear for organized storms will be in place along the front. The most favorable environment is expected near the track of the primary surface low from eastern ND into northern MN, where 40-50 kt of midlevel flow will overlap strong to extreme instability. Supercell development will be possible near the low track and in the vicinity of a warm front extending east-northeast from the low, with some clustering and upscale growth possible with time. With large-scale ascent tending to lag behind the front, coverage of storms into early evening is uncertain, but any supercells could pose a threat of all severe hazards, including tornado and very large hail potential. Any organized upscale growth would result in an increasing damaging-wind threat (including conditional potential for gusts near/above 75 mph) as storms spread east-northeastward into the evening. More isolated severe storms will also be possible within the post-frontal regime across the northern High Plains, where moderate MUCAPE and sufficient deep-layer shear could support isolated supercells or small clusters capable of severe hail and wind. Farther south into the central Plains, both instability and deep-layer shear will be somewhat weaker, due to warmer temperatures aloft and weaker flow. However, strong heating near and east of a developing secondary low across the central High Plains could result in scattered storm development near the front by evening. Relatively unidirectional southwesterly flow could result in a few stronger northeastward-moving cells/clusters capable of damaging wind and isolated hail. Scattered storms will also be possible within a weakly capped environment into parts of the southern High Plains. While deep-layer flow/shear will weaker in this area, moderate buoyancy and steep low-level lapse rates could support isolated severe gusts with the strongest storms. ...Parts of the Northeast/New England... Isolated strong storms may be ongoing Sunday morning across parts of the Northeast/New England, within a low-level warm advection regime. Confidence is low in the details, due to model variance regarding the strength and timing of the shortwave trough and surface low that will move through the region. Increasing instability and sufficient deep-layer shear will conditionally support organized convection through the day. At this time, the most likely scenario is for an isolated severe threat to persist through parts of the morning, before diminishing during the afternoon as the upper ridge builds into the region. However, with strong to extreme buoyancy expected to develop during the afternoon, the area will need to be closely monitored for diurnal redevelopment along any remnant surface boundaries. ..Dean.. 06/21/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sat Jun 21 2025 Valid 221200Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST INTO CENTRAL NE... ...SUMMARY... Severe thunderstorms are possible on Sunday from parts of the central and northern Plains into the upper Midwest. Significant hail and wind are possible across parts of eastern North Dakota and northern Minnesota, along with some tornado potential. ...Synopsis... A mid/upper-level low initially over ID is forecast to move northeastward as a shortwave trough Sunday, reaching parts of the northern Great Plains and Canadian Prairies by Sunday night. As this occurs, a surface low initially over parts of NE/SD will move toward northwest MN, as a trailing cold front moves across parts of the central/northern Plains and Upper Midwest. Farther east, a mid/upper-level shortwave trough and associated surface low and weak cold front will move across parts of New England. Guidance continues to vary regarding the timing and intensity of this system. In the wake of this shortwave trough, an upper ridge will amplify into parts of the Northeast. ...Great Plains into the Upper Midwest/Great Lakes... Strong to extreme instability will again develop from the central/northern Plains into the Upper Midwest and Great Lakes, along/ahead of the front. Stronger deep-layer flow and ascent will tend to lag behind the front, though sufficient vertical shear for organized storms will be in place along the front. The most favorable environment is expected near the track of the primary surface low from eastern ND into northern MN, where 40-50 kt of midlevel flow will overlap strong to extreme instability. Supercell development will be possible near the low track and in the vicinity of a warm front extending east-northeast from the low, with some clustering and upscale growth possible with time. With large-scale ascent tending to lag behind the front, coverage of storms into early evening is uncertain, but any supercells could pose a threat of all severe hazards, including tornado and very large hail potential. Any organized upscale growth would result in an increasing damaging-wind threat (including conditional potential for gusts near/above 75 mph) as storms spread east-northeastward into the evening. More isolated severe storms will also be possible within the post-frontal regime across the northern High Plains, where moderate MUCAPE and sufficient deep-layer shear could support isolated supercells or small clusters capable of severe hail and wind. Farther south into the central Plains, both instability and deep-layer shear will be somewhat weaker, due to warmer temperatures aloft and weaker flow. However, strong heating near and east of a developing secondary low across the central High Plains could result in scattered storm development near the front by evening. Relatively unidirectional southwesterly flow could result in a few stronger northeastward-moving cells/clusters capable of damaging wind and isolated hail. Scattered storms will also be possible within a weakly capped environment into parts of the southern High Plains. While deep-layer flow/shear will weaker in this area, moderate buoyancy and steep low-level lapse rates could support isolated severe gusts with the strongest storms. ...Parts of the Northeast/New England... Isolated strong storms may be ongoing Sunday morning across parts of the Northeast/New England, within a low-level warm advection regime. Confidence is low in the details, due to model variance regarding the strength and timing of the shortwave trough and surface low that will move through the region. Increasing instability and sufficient deep-layer shear will conditionally support organized convection through the day. At this time, the most likely scenario is for an isolated severe threat to persist through parts of the morning, before diminishing during the afternoon as the upper ridge builds into the region. However, with strong to extreme buoyancy expected to develop during the afternoon, the area will need to be closely monitored for diurnal redevelopment along any remnant surface boundaries. ..Dean.. 06/21/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sat Jun 21 2025 Valid 221200Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST INTO CENTRAL NE... ...SUMMARY... Severe thunderstorms are possible on Sunday from parts of the central and northern Plains into the upper Midwest. Significant hail and wind are possible across parts of eastern North Dakota and northern Minnesota, along with some tornado potential. ...Synopsis... A mid/upper-level low initially over ID is forecast to move northeastward as a shortwave trough Sunday, reaching parts of the northern Great Plains and Canadian Prairies by Sunday night. As this occurs, a surface low initially over parts of NE/SD will move toward northwest MN, as a trailing cold front moves across parts of the central/northern Plains and Upper Midwest. Farther east, a mid/upper-level shortwave trough and associated surface low and weak cold front will move across parts of New England. Guidance continues to vary regarding the timing and intensity of this system. In the wake of this shortwave trough, an upper ridge will amplify into parts of the Northeast. ...Great Plains into the Upper Midwest/Great Lakes... Strong to extreme instability will again develop from the central/northern Plains into the Upper Midwest and Great Lakes, along/ahead of the front. Stronger deep-layer flow and ascent will tend to lag behind the front, though sufficient vertical shear for organized storms will be in place along the front. The most favorable environment is expected near the track of the primary surface low from eastern ND into northern MN, where 40-50 kt of midlevel flow will overlap strong to extreme instability. Supercell development will be possible near the low track and in the vicinity of a warm front extending east-northeast from the low, with some clustering and upscale growth possible with time. With large-scale ascent tending to lag behind the front, coverage of storms into early evening is uncertain, but any supercells could pose a threat of all severe hazards, including tornado and very large hail potential. Any organized upscale growth would result in an increasing damaging-wind threat (including conditional potential for gusts near/above 75 mph) as storms spread east-northeastward into the evening. More isolated severe storms will also be possible within the post-frontal regime across the northern High Plains, where moderate MUCAPE and sufficient deep-layer shear could support isolated supercells or small clusters capable of severe hail and wind. Farther south into the central Plains, both instability and deep-layer shear will be somewhat weaker, due to warmer temperatures aloft and weaker flow. However, strong heating near and east of a developing secondary low across the central High Plains could result in scattered storm development near the front by evening. Relatively unidirectional southwesterly flow could result in a few stronger northeastward-moving cells/clusters capable of damaging wind and isolated hail. Scattered storms will also be possible within a weakly capped environment into parts of the southern High Plains. While deep-layer flow/shear will weaker in this area, moderate buoyancy and steep low-level lapse rates could support isolated severe gusts with the strongest storms. ...Parts of the Northeast/New England... Isolated strong storms may be ongoing Sunday morning across parts of the Northeast/New England, within a low-level warm advection regime. Confidence is low in the details, due to model variance regarding the strength and timing of the shortwave trough and surface low that will move through the region. Increasing instability and sufficient deep-layer shear will conditionally support organized convection through the day. At this time, the most likely scenario is for an isolated severe threat to persist through parts of the morning, before diminishing during the afternoon as the upper ridge builds into the region. However, with strong to extreme buoyancy expected to develop during the afternoon, the area will need to be closely monitored for diurnal redevelopment along any remnant surface boundaries. ..Dean.. 06/21/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sat Jun 21 2025 Valid 221200Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST INTO CENTRAL NE... ...SUMMARY... Severe thunderstorms are possible on Sunday from parts of the central and northern Plains into the upper Midwest. Significant hail and wind are possible across parts of eastern North Dakota and northern Minnesota, along with some tornado potential. ...Synopsis... A mid/upper-level low initially over ID is forecast to move northeastward as a shortwave trough Sunday, reaching parts of the northern Great Plains and Canadian Prairies by Sunday night. As this occurs, a surface low initially over parts of NE/SD will move toward northwest MN, as a trailing cold front moves across parts of the central/northern Plains and Upper Midwest. Farther east, a mid/upper-level shortwave trough and associated surface low and weak cold front will move across parts of New England. Guidance continues to vary regarding the timing and intensity of this system. In the wake of this shortwave trough, an upper ridge will amplify into parts of the Northeast. ...Great Plains into the Upper Midwest/Great Lakes... Strong to extreme instability will again develop from the central/northern Plains into the Upper Midwest and Great Lakes, along/ahead of the front. Stronger deep-layer flow and ascent will tend to lag behind the front, though sufficient vertical shear for organized storms will be in place along the front. The most favorable environment is expected near the track of the primary surface low from eastern ND into northern MN, where 40-50 kt of midlevel flow will overlap strong to extreme instability. Supercell development will be possible near the low track and in the vicinity of a warm front extending east-northeast from the low, with some clustering and upscale growth possible with time. With large-scale ascent tending to lag behind the front, coverage of storms into early evening is uncertain, but any supercells could pose a threat of all severe hazards, including tornado and very large hail potential. Any organized upscale growth would result in an increasing damaging-wind threat (including conditional potential for gusts near/above 75 mph) as storms spread east-northeastward into the evening. More isolated severe storms will also be possible within the post-frontal regime across the northern High Plains, where moderate MUCAPE and sufficient deep-layer shear could support isolated supercells or small clusters capable of severe hail and wind. Farther south into the central Plains, both instability and deep-layer shear will be somewhat weaker, due to warmer temperatures aloft and weaker flow. However, strong heating near and east of a developing secondary low across the central High Plains could result in scattered storm development near the front by evening. Relatively unidirectional southwesterly flow could result in a few stronger northeastward-moving cells/clusters capable of damaging wind and isolated hail. Scattered storms will also be possible within a weakly capped environment into parts of the southern High Plains. While deep-layer flow/shear will weaker in this area, moderate buoyancy and steep low-level lapse rates could support isolated severe gusts with the strongest storms. ...Parts of the Northeast/New England... Isolated strong storms may be ongoing Sunday morning across parts of the Northeast/New England, within a low-level warm advection regime. Confidence is low in the details, due to model variance regarding the strength and timing of the shortwave trough and surface low that will move through the region. Increasing instability and sufficient deep-layer shear will conditionally support organized convection through the day. At this time, the most likely scenario is for an isolated severe threat to persist through parts of the morning, before diminishing during the afternoon as the upper ridge builds into the region. However, with strong to extreme buoyancy expected to develop during the afternoon, the area will need to be closely monitored for diurnal redevelopment along any remnant surface boundaries. ..Dean.. 06/21/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sat Jun 21 2025 Valid 221200Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST INTO CENTRAL NE... ...SUMMARY... Severe thunderstorms are possible on Sunday from parts of the central and northern Plains into the upper Midwest. Significant hail and wind are possible across parts of eastern North Dakota and northern Minnesota, along with some tornado potential. ...Synopsis... A mid/upper-level low initially over ID is forecast to move northeastward as a shortwave trough Sunday, reaching parts of the northern Great Plains and Canadian Prairies by Sunday night. As this occurs, a surface low initially over parts of NE/SD will move toward northwest MN, as a trailing cold front moves across parts of the central/northern Plains and Upper Midwest. Farther east, a mid/upper-level shortwave trough and associated surface low and weak cold front will move across parts of New England. Guidance continues to vary regarding the timing and intensity of this system. In the wake of this shortwave trough, an upper ridge will amplify into parts of the Northeast. ...Great Plains into the Upper Midwest/Great Lakes... Strong to extreme instability will again develop from the central/northern Plains into the Upper Midwest and Great Lakes, along/ahead of the front. Stronger deep-layer flow and ascent will tend to lag behind the front, though sufficient vertical shear for organized storms will be in place along the front. The most favorable environment is expected near the track of the primary surface low from eastern ND into northern MN, where 40-50 kt of midlevel flow will overlap strong to extreme instability. Supercell development will be possible near the low track and in the vicinity of a warm front extending east-northeast from the low, with some clustering and upscale growth possible with time. With large-scale ascent tending to lag behind the front, coverage of storms into early evening is uncertain, but any supercells could pose a threat of all severe hazards, including tornado and very large hail potential. Any organized upscale growth would result in an increasing damaging-wind threat (including conditional potential for gusts near/above 75 mph) as storms spread east-northeastward into the evening. More isolated severe storms will also be possible within the post-frontal regime across the northern High Plains, where moderate MUCAPE and sufficient deep-layer shear could support isolated supercells or small clusters capable of severe hail and wind. Farther south into the central Plains, both instability and deep-layer shear will be somewhat weaker, due to warmer temperatures aloft and weaker flow. However, strong heating near and east of a developing secondary low across the central High Plains could result in scattered storm development near the front by evening. Relatively unidirectional southwesterly flow could result in a few stronger northeastward-moving cells/clusters capable of damaging wind and isolated hail. Scattered storms will also be possible within a weakly capped environment into parts of the southern High Plains. While deep-layer flow/shear will weaker in this area, moderate buoyancy and steep low-level lapse rates could support isolated severe gusts with the strongest storms. ...Parts of the Northeast/New England... Isolated strong storms may be ongoing Sunday morning across parts of the Northeast/New England, within a low-level warm advection regime. Confidence is low in the details, due to model variance regarding the strength and timing of the shortwave trough and surface low that will move through the region. Increasing instability and sufficient deep-layer shear will conditionally support organized convection through the day. At this time, the most likely scenario is for an isolated severe threat to persist through parts of the morning, before diminishing during the afternoon as the upper ridge builds into the region. However, with strong to extreme buoyancy expected to develop during the afternoon, the area will need to be closely monitored for diurnal redevelopment along any remnant surface boundaries. ..Dean.. 06/21/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Sat Jun 21 2025 Valid 211200Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE GREAT LAKES REGION... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts and hail will be possible today from the northern Plains into the Upper Mississippi Valley and Great Lakes. ...Great Lakes... A mid-level ridge will move quickly eastward into the Northeast today, as trailing shortwave trough moves through the Great Lakes. An MCS with some severe potential will likely be ongoing at the start of the period in the vicinity of Lake Superior. Warm-advection-related convection is expected to develop along the southern edge of the decaying MCS from the Upper Peninsula of Michigan eastward into northern sections of the Lower Peninsula of Michigan. As low-level lapse rates steepen during the morning, isolated damaging wind gusts will be possible with short line segments. During the afternoon, the brunt of the convection is forecast to move across southwestern Ontario. The southern edge of this cluster may move back into the lower 48, affecting parts of New York during the late afternoon. In central New York, moderate instability is forecast along with northwest mid-level flow around 50 knots. This should be enough for an isolated wind-damage threat with the faster-moving short line segments. Hail will also be possible with the stronger cores. Further south into parts of northern Pennsylvania, moderate instability is forecast to develop by afternoon. Due to a lack of large-scale ascent, convective coverage is expected to be very isolated. Any cell that can initiate in the higher terrain could have potential for marginally severe wind gusts. ...Northern Plains/Upper Mississippi Valley... Anticyclonic southwesterly mid-level flow will be in place today across much of the north-central U.S. At the surface, a post-frontal airmass will be in place over much of the northern Plains. Behind the front, a moist airmass will remain over parts of the Dakotas, where surface heating should yield moderate instability by afternoon. Although large-scale ascent will remain weak across most of the region, pockets of low-level convergence are forecast to develop within this airmass. This should be enough for isolated convective initiation during the mid to late afternoon. Marginally severe wind gusts and hail will be the primary threats. Further west into the northern High Plains, scattered thunderstorms are expected to develop during the overnight period, ahead of a mid-level trough in the northwestern U.S. Although a relatively dry airmass will be in place, low to mid-level lapse rates will be steep, and could be enough for a marginal wind-damage threat. ..Broyles/Moore.. 06/21/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Sat Jun 21 2025 Valid 211200Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE GREAT LAKES REGION... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts and hail will be possible today from the northern Plains into the Upper Mississippi Valley and Great Lakes. ...Great Lakes... A mid-level ridge will move quickly eastward into the Northeast today, as trailing shortwave trough moves through the Great Lakes. An MCS with some severe potential will likely be ongoing at the start of the period in the vicinity of Lake Superior. Warm-advection-related convection is expected to develop along the southern edge of the decaying MCS from the Upper Peninsula of Michigan eastward into northern sections of the Lower Peninsula of Michigan. As low-level lapse rates steepen during the morning, isolated damaging wind gusts will be possible with short line segments. During the afternoon, the brunt of the convection is forecast to move across southwestern Ontario. The southern edge of this cluster may move back into the lower 48, affecting parts of New York during the late afternoon. In central New York, moderate instability is forecast along with northwest mid-level flow around 50 knots. This should be enough for an isolated wind-damage threat with the faster-moving short line segments. Hail will also be possible with the stronger cores. Further south into parts of northern Pennsylvania, moderate instability is forecast to develop by afternoon. Due to a lack of large-scale ascent, convective coverage is expected to be very isolated. Any cell that can initiate in the higher terrain could have potential for marginally severe wind gusts. ...Northern Plains/Upper Mississippi Valley... Anticyclonic southwesterly mid-level flow will be in place today across much of the north-central U.S. At the surface, a post-frontal airmass will be in place over much of the northern Plains. Behind the front, a moist airmass will remain over parts of the Dakotas, where surface heating should yield moderate instability by afternoon. Although large-scale ascent will remain weak across most of the region, pockets of low-level convergence are forecast to develop within this airmass. This should be enough for isolated convective initiation during the mid to late afternoon. Marginally severe wind gusts and hail will be the primary threats. Further west into the northern High Plains, scattered thunderstorms are expected to develop during the overnight period, ahead of a mid-level trough in the northwestern U.S. Although a relatively dry airmass will be in place, low to mid-level lapse rates will be steep, and could be enough for a marginal wind-damage threat. ..Broyles/Moore.. 06/21/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Sat Jun 21 2025 Valid 211200Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE GREAT LAKES REGION... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts and hail will be possible today from the northern Plains into the Upper Mississippi Valley and Great Lakes. ...Great Lakes... A mid-level ridge will move quickly eastward into the Northeast today, as trailing shortwave trough moves through the Great Lakes. An MCS with some severe potential will likely be ongoing at the start of the period in the vicinity of Lake Superior. Warm-advection-related convection is expected to develop along the southern edge of the decaying MCS from the Upper Peninsula of Michigan eastward into northern sections of the Lower Peninsula of Michigan. As low-level lapse rates steepen during the morning, isolated damaging wind gusts will be possible with short line segments. During the afternoon, the brunt of the convection is forecast to move across southwestern Ontario. The southern edge of this cluster may move back into the lower 48, affecting parts of New York during the late afternoon. In central New York, moderate instability is forecast along with northwest mid-level flow around 50 knots. This should be enough for an isolated wind-damage threat with the faster-moving short line segments. Hail will also be possible with the stronger cores. Further south into parts of northern Pennsylvania, moderate instability is forecast to develop by afternoon. Due to a lack of large-scale ascent, convective coverage is expected to be very isolated. Any cell that can initiate in the higher terrain could have potential for marginally severe wind gusts. ...Northern Plains/Upper Mississippi Valley... Anticyclonic southwesterly mid-level flow will be in place today across much of the north-central U.S. At the surface, a post-frontal airmass will be in place over much of the northern Plains. Behind the front, a moist airmass will remain over parts of the Dakotas, where surface heating should yield moderate instability by afternoon. Although large-scale ascent will remain weak across most of the region, pockets of low-level convergence are forecast to develop within this airmass. This should be enough for isolated convective initiation during the mid to late afternoon. Marginally severe wind gusts and hail will be the primary threats. Further west into the northern High Plains, scattered thunderstorms are expected to develop during the overnight period, ahead of a mid-level trough in the northwestern U.S. Although a relatively dry airmass will be in place, low to mid-level lapse rates will be steep, and could be enough for a marginal wind-damage threat. ..Broyles/Moore.. 06/21/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Sat Jun 21 2025 Valid 211200Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE GREAT LAKES REGION... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts and hail will be possible today from the northern Plains into the Upper Mississippi Valley and Great Lakes. ...Great Lakes... A mid-level ridge will move quickly eastward into the Northeast today, as trailing shortwave trough moves through the Great Lakes. An MCS with some severe potential will likely be ongoing at the start of the period in the vicinity of Lake Superior. Warm-advection-related convection is expected to develop along the southern edge of the decaying MCS from the Upper Peninsula of Michigan eastward into northern sections of the Lower Peninsula of Michigan. As low-level lapse rates steepen during the morning, isolated damaging wind gusts will be possible with short line segments. During the afternoon, the brunt of the convection is forecast to move across southwestern Ontario. The southern edge of this cluster may move back into the lower 48, affecting parts of New York during the late afternoon. In central New York, moderate instability is forecast along with northwest mid-level flow around 50 knots. This should be enough for an isolated wind-damage threat with the faster-moving short line segments. Hail will also be possible with the stronger cores. Further south into parts of northern Pennsylvania, moderate instability is forecast to develop by afternoon. Due to a lack of large-scale ascent, convective coverage is expected to be very isolated. Any cell that can initiate in the higher terrain could have potential for marginally severe wind gusts. ...Northern Plains/Upper Mississippi Valley... Anticyclonic southwesterly mid-level flow will be in place today across much of the north-central U.S. At the surface, a post-frontal airmass will be in place over much of the northern Plains. Behind the front, a moist airmass will remain over parts of the Dakotas, where surface heating should yield moderate instability by afternoon. Although large-scale ascent will remain weak across most of the region, pockets of low-level convergence are forecast to develop within this airmass. This should be enough for isolated convective initiation during the mid to late afternoon. Marginally severe wind gusts and hail will be the primary threats. Further west into the northern High Plains, scattered thunderstorms are expected to develop during the overnight period, ahead of a mid-level trough in the northwestern U.S. Although a relatively dry airmass will be in place, low to mid-level lapse rates will be steep, and could be enough for a marginal wind-damage threat. ..Broyles/Moore.. 06/21/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Sat Jun 21 2025 Valid 211200Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE GREAT LAKES REGION... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts and hail will be possible today from the northern Plains into the Upper Mississippi Valley and Great Lakes. ...Great Lakes... A mid-level ridge will move quickly eastward into the Northeast today, as trailing shortwave trough moves through the Great Lakes. An MCS with some severe potential will likely be ongoing at the start of the period in the vicinity of Lake Superior. Warm-advection-related convection is expected to develop along the southern edge of the decaying MCS from the Upper Peninsula of Michigan eastward into northern sections of the Lower Peninsula of Michigan. As low-level lapse rates steepen during the morning, isolated damaging wind gusts will be possible with short line segments. During the afternoon, the brunt of the convection is forecast to move across southwestern Ontario. The southern edge of this cluster may move back into the lower 48, affecting parts of New York during the late afternoon. In central New York, moderate instability is forecast along with northwest mid-level flow around 50 knots. This should be enough for an isolated wind-damage threat with the faster-moving short line segments. Hail will also be possible with the stronger cores. Further south into parts of northern Pennsylvania, moderate instability is forecast to develop by afternoon. Due to a lack of large-scale ascent, convective coverage is expected to be very isolated. Any cell that can initiate in the higher terrain could have potential for marginally severe wind gusts. ...Northern Plains/Upper Mississippi Valley... Anticyclonic southwesterly mid-level flow will be in place today across much of the north-central U.S. At the surface, a post-frontal airmass will be in place over much of the northern Plains. Behind the front, a moist airmass will remain over parts of the Dakotas, where surface heating should yield moderate instability by afternoon. Although large-scale ascent will remain weak across most of the region, pockets of low-level convergence are forecast to develop within this airmass. This should be enough for isolated convective initiation during the mid to late afternoon. Marginally severe wind gusts and hail will be the primary threats. Further west into the northern High Plains, scattered thunderstorms are expected to develop during the overnight period, ahead of a mid-level trough in the northwestern U.S. Although a relatively dry airmass will be in place, low to mid-level lapse rates will be steep, and could be enough for a marginal wind-damage threat. ..Broyles/Moore.. 06/21/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Sat Jun 21 2025 Valid 211200Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE GREAT LAKES REGION... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts and hail will be possible today from the northern Plains into the Upper Mississippi Valley and Great Lakes. ...Great Lakes... A mid-level ridge will move quickly eastward into the Northeast today, as trailing shortwave trough moves through the Great Lakes. An MCS with some severe potential will likely be ongoing at the start of the period in the vicinity of Lake Superior. Warm-advection-related convection is expected to develop along the southern edge of the decaying MCS from the Upper Peninsula of Michigan eastward into northern sections of the Lower Peninsula of Michigan. As low-level lapse rates steepen during the morning, isolated damaging wind gusts will be possible with short line segments. During the afternoon, the brunt of the convection is forecast to move across southwestern Ontario. The southern edge of this cluster may move back into the lower 48, affecting parts of New York during the late afternoon. In central New York, moderate instability is forecast along with northwest mid-level flow around 50 knots. This should be enough for an isolated wind-damage threat with the faster-moving short line segments. Hail will also be possible with the stronger cores. Further south into parts of northern Pennsylvania, moderate instability is forecast to develop by afternoon. Due to a lack of large-scale ascent, convective coverage is expected to be very isolated. Any cell that can initiate in the higher terrain could have potential for marginally severe wind gusts. ...Northern Plains/Upper Mississippi Valley... Anticyclonic southwesterly mid-level flow will be in place today across much of the north-central U.S. At the surface, a post-frontal airmass will be in place over much of the northern Plains. Behind the front, a moist airmass will remain over parts of the Dakotas, where surface heating should yield moderate instability by afternoon. Although large-scale ascent will remain weak across most of the region, pockets of low-level convergence are forecast to develop within this airmass. This should be enough for isolated convective initiation during the mid to late afternoon. Marginally severe wind gusts and hail will be the primary threats. Further west into the northern High Plains, scattered thunderstorms are expected to develop during the overnight period, ahead of a mid-level trough in the northwestern U.S. Although a relatively dry airmass will be in place, low to mid-level lapse rates will be steep, and could be enough for a marginal wind-damage threat. ..Broyles/Moore.. 06/21/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Sat Jun 21 2025 Valid 211200Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE GREAT LAKES REGION... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts and hail will be possible today from the northern Plains into the Upper Mississippi Valley and Great Lakes. ...Great Lakes... A mid-level ridge will move quickly eastward into the Northeast today, as trailing shortwave trough moves through the Great Lakes. An MCS with some severe potential will likely be ongoing at the start of the period in the vicinity of Lake Superior. Warm-advection-related convection is expected to develop along the southern edge of the decaying MCS from the Upper Peninsula of Michigan eastward into northern sections of the Lower Peninsula of Michigan. As low-level lapse rates steepen during the morning, isolated damaging wind gusts will be possible with short line segments. During the afternoon, the brunt of the convection is forecast to move across southwestern Ontario. The southern edge of this cluster may move back into the lower 48, affecting parts of New York during the late afternoon. In central New York, moderate instability is forecast along with northwest mid-level flow around 50 knots. This should be enough for an isolated wind-damage threat with the faster-moving short line segments. Hail will also be possible with the stronger cores. Further south into parts of northern Pennsylvania, moderate instability is forecast to develop by afternoon. Due to a lack of large-scale ascent, convective coverage is expected to be very isolated. Any cell that can initiate in the higher terrain could have potential for marginally severe wind gusts. ...Northern Plains/Upper Mississippi Valley... Anticyclonic southwesterly mid-level flow will be in place today across much of the north-central U.S. At the surface, a post-frontal airmass will be in place over much of the northern Plains. Behind the front, a moist airmass will remain over parts of the Dakotas, where surface heating should yield moderate instability by afternoon. Although large-scale ascent will remain weak across most of the region, pockets of low-level convergence are forecast to develop within this airmass. This should be enough for isolated convective initiation during the mid to late afternoon. Marginally severe wind gusts and hail will be the primary threats. Further west into the northern High Plains, scattered thunderstorms are expected to develop during the overnight period, ahead of a mid-level trough in the northwestern U.S. Although a relatively dry airmass will be in place, low to mid-level lapse rates will be steep, and could be enough for a marginal wind-damage threat. ..Broyles/Moore.. 06/21/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Sat Jun 21 2025 Valid 211200Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE GREAT LAKES REGION... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts and hail will be possible today from the northern Plains into the Upper Mississippi Valley and Great Lakes. ...Great Lakes... A mid-level ridge will move quickly eastward into the Northeast today, as trailing shortwave trough moves through the Great Lakes. An MCS with some severe potential will likely be ongoing at the start of the period in the vicinity of Lake Superior. Warm-advection-related convection is expected to develop along the southern edge of the decaying MCS from the Upper Peninsula of Michigan eastward into northern sections of the Lower Peninsula of Michigan. As low-level lapse rates steepen during the morning, isolated damaging wind gusts will be possible with short line segments. During the afternoon, the brunt of the convection is forecast to move across southwestern Ontario. The southern edge of this cluster may move back into the lower 48, affecting parts of New York during the late afternoon. In central New York, moderate instability is forecast along with northwest mid-level flow around 50 knots. This should be enough for an isolated wind-damage threat with the faster-moving short line segments. Hail will also be possible with the stronger cores. Further south into parts of northern Pennsylvania, moderate instability is forecast to develop by afternoon. Due to a lack of large-scale ascent, convective coverage is expected to be very isolated. Any cell that can initiate in the higher terrain could have potential for marginally severe wind gusts. ...Northern Plains/Upper Mississippi Valley... Anticyclonic southwesterly mid-level flow will be in place today across much of the north-central U.S. At the surface, a post-frontal airmass will be in place over much of the northern Plains. Behind the front, a moist airmass will remain over parts of the Dakotas, where surface heating should yield moderate instability by afternoon. Although large-scale ascent will remain weak across most of the region, pockets of low-level convergence are forecast to develop within this airmass. This should be enough for isolated convective initiation during the mid to late afternoon. Marginally severe wind gusts and hail will be the primary threats. Further west into the northern High Plains, scattered thunderstorms are expected to develop during the overnight period, ahead of a mid-level trough in the northwestern U.S. Although a relatively dry airmass will be in place, low to mid-level lapse rates will be steep, and could be enough for a marginal wind-damage threat. ..Broyles/Moore.. 06/21/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Sat Jun 21 2025 Valid 211200Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE GREAT LAKES REGION... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts and hail will be possible today from the northern Plains into the Upper Mississippi Valley and Great Lakes. ...Great Lakes... A mid-level ridge will move quickly eastward into the Northeast today, as trailing shortwave trough moves through the Great Lakes. An MCS with some severe potential will likely be ongoing at the start of the period in the vicinity of Lake Superior. Warm-advection-related convection is expected to develop along the southern edge of the decaying MCS from the Upper Peninsula of Michigan eastward into northern sections of the Lower Peninsula of Michigan. As low-level lapse rates steepen during the morning, isolated damaging wind gusts will be possible with short line segments. During the afternoon, the brunt of the convection is forecast to move across southwestern Ontario. The southern edge of this cluster may move back into the lower 48, affecting parts of New York during the late afternoon. In central New York, moderate instability is forecast along with northwest mid-level flow around 50 knots. This should be enough for an isolated wind-damage threat with the faster-moving short line segments. Hail will also be possible with the stronger cores. Further south into parts of northern Pennsylvania, moderate instability is forecast to develop by afternoon. Due to a lack of large-scale ascent, convective coverage is expected to be very isolated. Any cell that can initiate in the higher terrain could have potential for marginally severe wind gusts. ...Northern Plains/Upper Mississippi Valley... Anticyclonic southwesterly mid-level flow will be in place today across much of the north-central U.S. At the surface, a post-frontal airmass will be in place over much of the northern Plains. Behind the front, a moist airmass will remain over parts of the Dakotas, where surface heating should yield moderate instability by afternoon. Although large-scale ascent will remain weak across most of the region, pockets of low-level convergence are forecast to develop within this airmass. This should be enough for isolated convective initiation during the mid to late afternoon. Marginally severe wind gusts and hail will be the primary threats. Further west into the northern High Plains, scattered thunderstorms are expected to develop during the overnight period, ahead of a mid-level trough in the northwestern U.S. Although a relatively dry airmass will be in place, low to mid-level lapse rates will be steep, and could be enough for a marginal wind-damage threat. ..Broyles/Moore.. 06/21/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Sat Jun 21 2025 Valid 211200Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE GREAT LAKES REGION... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts and hail will be possible today from the northern Plains into the Upper Mississippi Valley and Great Lakes. ...Great Lakes... A mid-level ridge will move quickly eastward into the Northeast today, as trailing shortwave trough moves through the Great Lakes. An MCS with some severe potential will likely be ongoing at the start of the period in the vicinity of Lake Superior. Warm-advection-related convection is expected to develop along the southern edge of the decaying MCS from the Upper Peninsula of Michigan eastward into northern sections of the Lower Peninsula of Michigan. As low-level lapse rates steepen during the morning, isolated damaging wind gusts will be possible with short line segments. During the afternoon, the brunt of the convection is forecast to move across southwestern Ontario. The southern edge of this cluster may move back into the lower 48, affecting parts of New York during the late afternoon. In central New York, moderate instability is forecast along with northwest mid-level flow around 50 knots. This should be enough for an isolated wind-damage threat with the faster-moving short line segments. Hail will also be possible with the stronger cores. Further south into parts of northern Pennsylvania, moderate instability is forecast to develop by afternoon. Due to a lack of large-scale ascent, convective coverage is expected to be very isolated. Any cell that can initiate in the higher terrain could have potential for marginally severe wind gusts. ...Northern Plains/Upper Mississippi Valley... Anticyclonic southwesterly mid-level flow will be in place today across much of the north-central U.S. At the surface, a post-frontal airmass will be in place over much of the northern Plains. Behind the front, a moist airmass will remain over parts of the Dakotas, where surface heating should yield moderate instability by afternoon. Although large-scale ascent will remain weak across most of the region, pockets of low-level convergence are forecast to develop within this airmass. This should be enough for isolated convective initiation during the mid to late afternoon. Marginally severe wind gusts and hail will be the primary threats. Further west into the northern High Plains, scattered thunderstorms are expected to develop during the overnight period, ahead of a mid-level trough in the northwestern U.S. Although a relatively dry airmass will be in place, low to mid-level lapse rates will be steep, and could be enough for a marginal wind-damage threat. ..Broyles/Moore.. 06/21/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Sat Jun 21 2025 Valid 211200Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE GREAT LAKES REGION... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts and hail will be possible today from the northern Plains into the Upper Mississippi Valley and Great Lakes. ...Great Lakes... A mid-level ridge will move quickly eastward into the Northeast today, as trailing shortwave trough moves through the Great Lakes. An MCS with some severe potential will likely be ongoing at the start of the period in the vicinity of Lake Superior. Warm-advection-related convection is expected to develop along the southern edge of the decaying MCS from the Upper Peninsula of Michigan eastward into northern sections of the Lower Peninsula of Michigan. As low-level lapse rates steepen during the morning, isolated damaging wind gusts will be possible with short line segments. During the afternoon, the brunt of the convection is forecast to move across southwestern Ontario. The southern edge of this cluster may move back into the lower 48, affecting parts of New York during the late afternoon. In central New York, moderate instability is forecast along with northwest mid-level flow around 50 knots. This should be enough for an isolated wind-damage threat with the faster-moving short line segments. Hail will also be possible with the stronger cores. Further south into parts of northern Pennsylvania, moderate instability is forecast to develop by afternoon. Due to a lack of large-scale ascent, convective coverage is expected to be very isolated. Any cell that can initiate in the higher terrain could have potential for marginally severe wind gusts. ...Northern Plains/Upper Mississippi Valley... Anticyclonic southwesterly mid-level flow will be in place today across much of the north-central U.S. At the surface, a post-frontal airmass will be in place over much of the northern Plains. Behind the front, a moist airmass will remain over parts of the Dakotas, where surface heating should yield moderate instability by afternoon. Although large-scale ascent will remain weak across most of the region, pockets of low-level convergence are forecast to develop within this airmass. This should be enough for isolated convective initiation during the mid to late afternoon. Marginally severe wind gusts and hail will be the primary threats. Further west into the northern High Plains, scattered thunderstorms are expected to develop during the overnight period, ahead of a mid-level trough in the northwestern U.S. Although a relatively dry airmass will be in place, low to mid-level lapse rates will be steep, and could be enough for a marginal wind-damage threat. ..Broyles/Moore.. 06/21/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Sat Jun 21 2025 Valid 211200Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE GREAT LAKES REGION... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts and hail will be possible today from the northern Plains into the Upper Mississippi Valley and Great Lakes. ...Great Lakes... A mid-level ridge will move quickly eastward into the Northeast today, as trailing shortwave trough moves through the Great Lakes. An MCS with some severe potential will likely be ongoing at the start of the period in the vicinity of Lake Superior. Warm-advection-related convection is expected to develop along the southern edge of the decaying MCS from the Upper Peninsula of Michigan eastward into northern sections of the Lower Peninsula of Michigan. As low-level lapse rates steepen during the morning, isolated damaging wind gusts will be possible with short line segments. During the afternoon, the brunt of the convection is forecast to move across southwestern Ontario. The southern edge of this cluster may move back into the lower 48, affecting parts of New York during the late afternoon. In central New York, moderate instability is forecast along with northwest mid-level flow around 50 knots. This should be enough for an isolated wind-damage threat with the faster-moving short line segments. Hail will also be possible with the stronger cores. Further south into parts of northern Pennsylvania, moderate instability is forecast to develop by afternoon. Due to a lack of large-scale ascent, convective coverage is expected to be very isolated. Any cell that can initiate in the higher terrain could have potential for marginally severe wind gusts. ...Northern Plains/Upper Mississippi Valley... Anticyclonic southwesterly mid-level flow will be in place today across much of the north-central U.S. At the surface, a post-frontal airmass will be in place over much of the northern Plains. Behind the front, a moist airmass will remain over parts of the Dakotas, where surface heating should yield moderate instability by afternoon. Although large-scale ascent will remain weak across most of the region, pockets of low-level convergence are forecast to develop within this airmass. This should be enough for isolated convective initiation during the mid to late afternoon. Marginally severe wind gusts and hail will be the primary threats. Further west into the northern High Plains, scattered thunderstorms are expected to develop during the overnight period, ahead of a mid-level trough in the northwestern U.S. Although a relatively dry airmass will be in place, low to mid-level lapse rates will be steep, and could be enough for a marginal wind-damage threat. ..Broyles/Moore.. 06/21/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Sat Jun 21 2025 Valid 211200Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE GREAT LAKES REGION... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts and hail will be possible today from the northern Plains into the Upper Mississippi Valley and Great Lakes. ...Great Lakes... A mid-level ridge will move quickly eastward into the Northeast today, as trailing shortwave trough moves through the Great Lakes. An MCS with some severe potential will likely be ongoing at the start of the period in the vicinity of Lake Superior. Warm-advection-related convection is expected to develop along the southern edge of the decaying MCS from the Upper Peninsula of Michigan eastward into northern sections of the Lower Peninsula of Michigan. As low-level lapse rates steepen during the morning, isolated damaging wind gusts will be possible with short line segments. During the afternoon, the brunt of the convection is forecast to move across southwestern Ontario. The southern edge of this cluster may move back into the lower 48, affecting parts of New York during the late afternoon. In central New York, moderate instability is forecast along with northwest mid-level flow around 50 knots. This should be enough for an isolated wind-damage threat with the faster-moving short line segments. Hail will also be possible with the stronger cores. Further south into parts of northern Pennsylvania, moderate instability is forecast to develop by afternoon. Due to a lack of large-scale ascent, convective coverage is expected to be very isolated. Any cell that can initiate in the higher terrain could have potential for marginally severe wind gusts. ...Northern Plains/Upper Mississippi Valley... Anticyclonic southwesterly mid-level flow will be in place today across much of the north-central U.S. At the surface, a post-frontal airmass will be in place over much of the northern Plains. Behind the front, a moist airmass will remain over parts of the Dakotas, where surface heating should yield moderate instability by afternoon. Although large-scale ascent will remain weak across most of the region, pockets of low-level convergence are forecast to develop within this airmass. This should be enough for isolated convective initiation during the mid to late afternoon. Marginally severe wind gusts and hail will be the primary threats. Further west into the northern High Plains, scattered thunderstorms are expected to develop during the overnight period, ahead of a mid-level trough in the northwestern U.S. Although a relatively dry airmass will be in place, low to mid-level lapse rates will be steep, and could be enough for a marginal wind-damage threat. ..Broyles/Moore.. 06/21/2025 Read more

MD 1392 CONCERNING TORNADO WATCH 449... FOR PORTIONS OF EASTERN NORTH DAKOTA INTO NORTHWESTERN MINNESOTA
Mesoscale Discussion 1392 NWS Storm Prediction Center Norman OK 1139 PM CDT Fri Jun 20 2025 Areas affected...portions of eastern North Dakota into northwestern Minnesota Concerning...Tornado Watch 449... Valid 210439Z - 210545Z The severe weather threat for Tornado Watch 449 continues. SUMMARY...A derecho may continue for a few more hours, with severe winds remaining widespread, and 75-100 mph gusts still possible in the short term. Several QLCS tornadoes may also occur. DISCUSSION...A derecho-producing bow-echo MCS continues to rapidly propagate eastward, accompanied by a widespread/high-end severe wind swath. Given the perseverance of a strong rear-inflow jet and large, line-end mesovortex, prolonged severe winds remain possible well into the trailing precipitation region of the parent bow-echo MCS, behind the leading line. To the east, tornadic supercells persist, with recent evidence of strong tornadoes. Over the next couple of hours, the bow-echo will merge with these supercells, and the supercells will persist for some time before gradually morphing into pronounced, deep mesovortices embedded in the line. Through this entire phase, severe winds and line-embedded tornadoes will remain a concern. 75-100 mph gusts and EF2+ tornadoes will be most likely in the early merging process. A few hours from now, mainly 65-75 mph winds will be likely, though a few embedded 75+ mph gusts and/or QLCS tornadoes will remain possible. ..Squitieri.. 06/21/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FGF...BIS... LAT...LON 47630038 47939887 48039749 48019638 47779587 47149543 46629543 46239589 46039680 46009783 46119833 46319880 46599944 46930009 47630038 MOST PROBABLE PEAK TORNADO INTENSITY...100-130 MPH MOST PROBABLE PEAK WIND GUST...95-115 MPH MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN Read more

MD 1391 CONCERNING SEVERE POTENTIAL...SEVERE THUNDERSTORM WATCH LIKELY FOR PORTIONS OF NORTHERN INTO NORTHEAST MINNESOTA AND EXTREME NORTHWESTERN WISCONSIN
Mesoscale Discussion 1391 NWS Storm Prediction Center Norman OK 1047 PM CDT Fri Jun 20 2025 Areas affected...portions of northern into northeast Minnesota and extreme northwestern Wisconsin Concerning...Severe potential...Severe Thunderstorm Watch likely Valid 210347Z - 210545Z Probability of Watch Issuance...95 percent SUMMARY...The severe threat will increase tonight as a bow-echo merges with supercells and progresses eastward as an organized MCS. Severe gusts will be the main threat, though some hail and perhaps a tornado are also possible. A WW issuance will eventually be needed. DISCUSSION...An intense bow-echo is rapidly propagating east-northeast across central ND, and will merge with tornadic supercells across eastern ND over the next couple hours. Afterwards, an MCS should continue to track eastward over northern MN through tonight. Though boundary-layer stabilization may gradually limit the severe nature of the ongoing storms to some degree, current thinking is that at an appreciable severe wind threat will remain. Furthermore, any semi-discrete convection that can initiate at the terminus of the low-level jet, or just ahead of an MCS, may also pose a large hail threat. Should a bow echo persist, QLCS tornadoes are also not entirely out of the question, though the tornado potential is more uncertain given nocturnal stabilization. Either way, the impending severe threat should warrant the eventual issuance of a Severe Thunderstorm Watch. ..Squitieri/Smith.. 06/21/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DLH...FGF... LAT...LON 48439562 48359355 47919185 47569117 47159103 46699116 46429160 46409232 46369312 46379389 46429474 46749526 47239550 48439562 MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH MOST PROBABLE PEAK WIND GUST...65-80 MPH MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN Read more