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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1159 AM CDT Thu Jul 11 2024 Valid 111700Z - 121200Z Dry thunderstorms are possible this afternoon and evening across portions of Northwestern Arizona, where it appears sufficient moisture over the higher terrain, coupled with hot, dry boundary layer profiles, could result in dry thunder occurrence over locally receptive fuels. Given these inverted-V profiles, gusty thunderstorm winds can be expected with any outflow that develops. However, the threat appears to be too localized to introduce a highlight area at this time. The remainder of the forecast remains unchanged and on-track. See previous discussion for further detail. ..Halbert/Weinman.. 07/11/2024 .PREV DISCUSSION... /ISSUED 0200 AM CDT Thu Jul 11 2024/ ...Synopsis... A mid/upper-level ridge will remain anchored over the Great Basin today, resulting in a continuation of very hot and dry conditions over much of the West. Multiple low-amplitude shortwave troughs will move along the western and northern periphery of the ridge, with a modest increase in low/midlevel flow expected from northern parts of the Great Basin into the interior Northwest. ...Snake River Plain of ID and vicinity... As flow gradually increases within a persistently hot and dry environment, several hours of elevated to locally critical conditions are expected across parts of the Snake River Plain and vicinity this afternoon into the early evening. Sustained winds are forecast to increase into the 15-20 mph range (with higher gusts), as RH potentially drops to near or below 10 percent. ...Northeast CA into northwest NV... A modest increase in low-level flow is also expected along the northwest periphery of the ridge, from parts of northeast CA into northwest NV. Sustained winds of 15-20 mph (with higher gusts) combined with hot and dry conditions (with RH falling below 10 percent) will result in elevated fire-weather conditions during the afternoon and early evening. ...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 1159 AM CDT Thu Jul 11 2024 Valid 111700Z - 121200Z Dry thunderstorms are possible this afternoon and evening across portions of Northwestern Arizona, where it appears sufficient moisture over the higher terrain, coupled with hot, dry boundary layer profiles, could result in dry thunder occurrence over locally receptive fuels. Given these inverted-V profiles, gusty thunderstorm winds can be expected with any outflow that develops. However, the threat appears to be too localized to introduce a highlight area at this time. The remainder of the forecast remains unchanged and on-track. See previous discussion for further detail. ..Halbert/Weinman.. 07/11/2024 .PREV DISCUSSION... /ISSUED 0200 AM CDT Thu Jul 11 2024/ ...Synopsis... A mid/upper-level ridge will remain anchored over the Great Basin today, resulting in a continuation of very hot and dry conditions over much of the West. Multiple low-amplitude shortwave troughs will move along the western and northern periphery of the ridge, with a modest increase in low/midlevel flow expected from northern parts of the Great Basin into the interior Northwest. ...Snake River Plain of ID and vicinity... As flow gradually increases within a persistently hot and dry environment, several hours of elevated to locally critical conditions are expected across parts of the Snake River Plain and vicinity this afternoon into the early evening. Sustained winds are forecast to increase into the 15-20 mph range (with higher gusts), as RH potentially drops to near or below 10 percent. ...Northeast CA into northwest NV... A modest increase in low-level flow is also expected along the northwest periphery of the ridge, from parts of northeast CA into northwest NV. Sustained winds of 15-20 mph (with higher gusts) combined with hot and dry conditions (with RH falling below 10 percent) will result in elevated fire-weather conditions during the afternoon and early evening. ...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 1159 AM CDT Thu Jul 11 2024 Valid 111700Z - 121200Z Dry thunderstorms are possible this afternoon and evening across portions of Northwestern Arizona, where it appears sufficient moisture over the higher terrain, coupled with hot, dry boundary layer profiles, could result in dry thunder occurrence over locally receptive fuels. Given these inverted-V profiles, gusty thunderstorm winds can be expected with any outflow that develops. However, the threat appears to be too localized to introduce a highlight area at this time. The remainder of the forecast remains unchanged and on-track. See previous discussion for further detail. ..Halbert/Weinman.. 07/11/2024 .PREV DISCUSSION... /ISSUED 0200 AM CDT Thu Jul 11 2024/ ...Synopsis... A mid/upper-level ridge will remain anchored over the Great Basin today, resulting in a continuation of very hot and dry conditions over much of the West. Multiple low-amplitude shortwave troughs will move along the western and northern periphery of the ridge, with a modest increase in low/midlevel flow expected from northern parts of the Great Basin into the interior Northwest. ...Snake River Plain of ID and vicinity... As flow gradually increases within a persistently hot and dry environment, several hours of elevated to locally critical conditions are expected across parts of the Snake River Plain and vicinity this afternoon into the early evening. Sustained winds are forecast to increase into the 15-20 mph range (with higher gusts), as RH potentially drops to near or below 10 percent. ...Northeast CA into northwest NV... A modest increase in low-level flow is also expected along the northwest periphery of the ridge, from parts of northeast CA into northwest NV. Sustained winds of 15-20 mph (with higher gusts) combined with hot and dry conditions (with RH falling below 10 percent) will result in elevated fire-weather conditions during the afternoon and early evening. ...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 1159 AM CDT Thu Jul 11 2024 Valid 111700Z - 121200Z Dry thunderstorms are possible this afternoon and evening across portions of Northwestern Arizona, where it appears sufficient moisture over the higher terrain, coupled with hot, dry boundary layer profiles, could result in dry thunder occurrence over locally receptive fuels. Given these inverted-V profiles, gusty thunderstorm winds can be expected with any outflow that develops. However, the threat appears to be too localized to introduce a highlight area at this time. The remainder of the forecast remains unchanged and on-track. See previous discussion for further detail. ..Halbert/Weinman.. 07/11/2024 .PREV DISCUSSION... /ISSUED 0200 AM CDT Thu Jul 11 2024/ ...Synopsis... A mid/upper-level ridge will remain anchored over the Great Basin today, resulting in a continuation of very hot and dry conditions over much of the West. Multiple low-amplitude shortwave troughs will move along the western and northern periphery of the ridge, with a modest increase in low/midlevel flow expected from northern parts of the Great Basin into the interior Northwest. ...Snake River Plain of ID and vicinity... As flow gradually increases within a persistently hot and dry environment, several hours of elevated to locally critical conditions are expected across parts of the Snake River Plain and vicinity this afternoon into the early evening. Sustained winds are forecast to increase into the 15-20 mph range (with higher gusts), as RH potentially drops to near or below 10 percent. ...Northeast CA into northwest NV... A modest increase in low-level flow is also expected along the northwest periphery of the ridge, from parts of northeast CA into northwest NV. Sustained winds of 15-20 mph (with higher gusts) combined with hot and dry conditions (with RH falling below 10 percent) will result in elevated fire-weather conditions during the afternoon and early evening. ...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 1159 AM CDT Thu Jul 11 2024 Valid 111700Z - 121200Z Dry thunderstorms are possible this afternoon and evening across portions of Northwestern Arizona, where it appears sufficient moisture over the higher terrain, coupled with hot, dry boundary layer profiles, could result in dry thunder occurrence over locally receptive fuels. Given these inverted-V profiles, gusty thunderstorm winds can be expected with any outflow that develops. However, the threat appears to be too localized to introduce a highlight area at this time. The remainder of the forecast remains unchanged and on-track. See previous discussion for further detail. ..Halbert/Weinman.. 07/11/2024 .PREV DISCUSSION... /ISSUED 0200 AM CDT Thu Jul 11 2024/ ...Synopsis... A mid/upper-level ridge will remain anchored over the Great Basin today, resulting in a continuation of very hot and dry conditions over much of the West. Multiple low-amplitude shortwave troughs will move along the western and northern periphery of the ridge, with a modest increase in low/midlevel flow expected from northern parts of the Great Basin into the interior Northwest. ...Snake River Plain of ID and vicinity... As flow gradually increases within a persistently hot and dry environment, several hours of elevated to locally critical conditions are expected across parts of the Snake River Plain and vicinity this afternoon into the early evening. Sustained winds are forecast to increase into the 15-20 mph range (with higher gusts), as RH potentially drops to near or below 10 percent. ...Northeast CA into northwest NV... A modest increase in low-level flow is also expected along the northwest periphery of the ridge, from parts of northeast CA into northwest NV. Sustained winds of 15-20 mph (with higher gusts) combined with hot and dry conditions (with RH falling below 10 percent) will result in elevated fire-weather conditions during the afternoon and early evening. ...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 1159 AM CDT Thu Jul 11 2024 Valid 111700Z - 121200Z Dry thunderstorms are possible this afternoon and evening across portions of Northwestern Arizona, where it appears sufficient moisture over the higher terrain, coupled with hot, dry boundary layer profiles, could result in dry thunder occurrence over locally receptive fuels. Given these inverted-V profiles, gusty thunderstorm winds can be expected with any outflow that develops. However, the threat appears to be too localized to introduce a highlight area at this time. The remainder of the forecast remains unchanged and on-track. See previous discussion for further detail. ..Halbert/Weinman.. 07/11/2024 .PREV DISCUSSION... /ISSUED 0200 AM CDT Thu Jul 11 2024/ ...Synopsis... A mid/upper-level ridge will remain anchored over the Great Basin today, resulting in a continuation of very hot and dry conditions over much of the West. Multiple low-amplitude shortwave troughs will move along the western and northern periphery of the ridge, with a modest increase in low/midlevel flow expected from northern parts of the Great Basin into the interior Northwest. ...Snake River Plain of ID and vicinity... As flow gradually increases within a persistently hot and dry environment, several hours of elevated to locally critical conditions are expected across parts of the Snake River Plain and vicinity this afternoon into the early evening. Sustained winds are forecast to increase into the 15-20 mph range (with higher gusts), as RH potentially drops to near or below 10 percent. ...Northeast CA into northwest NV... A modest increase in low-level flow is also expected along the northwest periphery of the ridge, from parts of northeast CA into northwest NV. Sustained winds of 15-20 mph (with higher gusts) combined with hot and dry conditions (with RH falling below 10 percent) will result in elevated fire-weather conditions during the afternoon and early evening. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1145 AM CDT Thu Jul 11 2024 Valid 111630Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN ARIZONA... ...SUMMARY... Severe thunderstorm wind gusts are possible over parts of southern Arizona from mid-afternoon through early/mid-evening. ...Arizona... Widely scattered to scattered thunderstorms are expected to develop this afternoon over the Mogollon Rim, and smaller mountain ranges to the south. That will occur as strong insolation at those higher elevations preferentially removes MLCINH, in the presence of generally greater low-level moisture than previous days. Some strengthening of flow aloft is expected over this region on the southeast periphery of the upper anticyclone. This will support convective motion off the Rim (and small mountain ranges to its south), into strongly heated/deeply mixed boundary layers of the desert floor. Isolated strong-severe gusts are possible from the relatively early, more-discrete activity, and swaths of strong-severe gusts are possible as convection moves southwestward toward the international border. ...Northern High Plains... Isolated to widely scattered, high-based thunderstorms are expected to form near the lee trough, where both relatively maximized convergence and strong surface heating should contribute to enough lift for convective initiation. The main concern should be damaging to severe gusts, given the deeply mixed subcloud layer. Isolated severe hail also may occur, amidst enough deep-layer shear for some organized thunderstorms (effective-shear magnitudes of 30-40 kt). Lack of greater moisture and buoyancy will be a limiting factor for coverage and intensity of convection, which should diminish rapidly after sunset. ...Southeast Kansas/Southern Missouri... A few severe storms could develop today to the east-northeast of a surface wave near the Oklahoma/Kansas border in vicinity of front that extends into Missouri, which may be somewhat effectively augmented by lingering early day convection. Moderate to locally strong buoyancy will exist within a moist environment, with MLCAPE likely to reach 2500-3000 J/kg. A considerable vertical veering of winds will exist through the lower/middle troposphere, with around 30 kt effective shear. Instances of severe hail and/or wind gusts could occur. ...Southern Maine... Clouds have lingered much of the morning with rather weak lapse rates noted in the 12z KGYX/Gray Maine observed sounding, but clearing is occurring from the west and a narrow zone of modest destabilization should occur this afternoon, within a very moist environment (lower/middle 70s F surface dewpoints) ahead of a cold front. Pending sufficient destabilization, a locally severe storm or two could occur, potentially with an absence of lightning, in the presence of long/semi-straight hodographs (highlighted by 45-50 kt winds 3-6 km AGL). ...Central/south-central portions of Illinois and Indiana... Ample low-level CAPE (100+ J/kg 0-km AGL) near the southward-shifting boundary could lead to some potential for funnels or perhaps even a brief non-supercell tornado this afternoon. Some of the storms could otherwise pose a risk for gusty winds, but the overall potential for organized severe storms is currently expected to remain low. ..Guyer/Wendt.. 07/11/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1145 AM CDT Thu Jul 11 2024 Valid 111630Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN ARIZONA... ...SUMMARY... Severe thunderstorm wind gusts are possible over parts of southern Arizona from mid-afternoon through early/mid-evening. ...Arizona... Widely scattered to scattered thunderstorms are expected to develop this afternoon over the Mogollon Rim, and smaller mountain ranges to the south. That will occur as strong insolation at those higher elevations preferentially removes MLCINH, in the presence of generally greater low-level moisture than previous days. Some strengthening of flow aloft is expected over this region on the southeast periphery of the upper anticyclone. This will support convective motion off the Rim (and small mountain ranges to its south), into strongly heated/deeply mixed boundary layers of the desert floor. Isolated strong-severe gusts are possible from the relatively early, more-discrete activity, and swaths of strong-severe gusts are possible as convection moves southwestward toward the international border. ...Northern High Plains... Isolated to widely scattered, high-based thunderstorms are expected to form near the lee trough, where both relatively maximized convergence and strong surface heating should contribute to enough lift for convective initiation. The main concern should be damaging to severe gusts, given the deeply mixed subcloud layer. Isolated severe hail also may occur, amidst enough deep-layer shear for some organized thunderstorms (effective-shear magnitudes of 30-40 kt). Lack of greater moisture and buoyancy will be a limiting factor for coverage and intensity of convection, which should diminish rapidly after sunset. ...Southeast Kansas/Southern Missouri... A few severe storms could develop today to the east-northeast of a surface wave near the Oklahoma/Kansas border in vicinity of front that extends into Missouri, which may be somewhat effectively augmented by lingering early day convection. Moderate to locally strong buoyancy will exist within a moist environment, with MLCAPE likely to reach 2500-3000 J/kg. A considerable vertical veering of winds will exist through the lower/middle troposphere, with around 30 kt effective shear. Instances of severe hail and/or wind gusts could occur. ...Southern Maine... Clouds have lingered much of the morning with rather weak lapse rates noted in the 12z KGYX/Gray Maine observed sounding, but clearing is occurring from the west and a narrow zone of modest destabilization should occur this afternoon, within a very moist environment (lower/middle 70s F surface dewpoints) ahead of a cold front. Pending sufficient destabilization, a locally severe storm or two could occur, potentially with an absence of lightning, in the presence of long/semi-straight hodographs (highlighted by 45-50 kt winds 3-6 km AGL). ...Central/south-central portions of Illinois and Indiana... Ample low-level CAPE (100+ J/kg 0-km AGL) near the southward-shifting boundary could lead to some potential for funnels or perhaps even a brief non-supercell tornado this afternoon. Some of the storms could otherwise pose a risk for gusty winds, but the overall potential for organized severe storms is currently expected to remain low. ..Guyer/Wendt.. 07/11/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1145 AM CDT Thu Jul 11 2024 Valid 111630Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN ARIZONA... ...SUMMARY... Severe thunderstorm wind gusts are possible over parts of southern Arizona from mid-afternoon through early/mid-evening. ...Arizona... Widely scattered to scattered thunderstorms are expected to develop this afternoon over the Mogollon Rim, and smaller mountain ranges to the south. That will occur as strong insolation at those higher elevations preferentially removes MLCINH, in the presence of generally greater low-level moisture than previous days. Some strengthening of flow aloft is expected over this region on the southeast periphery of the upper anticyclone. This will support convective motion off the Rim (and small mountain ranges to its south), into strongly heated/deeply mixed boundary layers of the desert floor. Isolated strong-severe gusts are possible from the relatively early, more-discrete activity, and swaths of strong-severe gusts are possible as convection moves southwestward toward the international border. ...Northern High Plains... Isolated to widely scattered, high-based thunderstorms are expected to form near the lee trough, where both relatively maximized convergence and strong surface heating should contribute to enough lift for convective initiation. The main concern should be damaging to severe gusts, given the deeply mixed subcloud layer. Isolated severe hail also may occur, amidst enough deep-layer shear for some organized thunderstorms (effective-shear magnitudes of 30-40 kt). Lack of greater moisture and buoyancy will be a limiting factor for coverage and intensity of convection, which should diminish rapidly after sunset. ...Southeast Kansas/Southern Missouri... A few severe storms could develop today to the east-northeast of a surface wave near the Oklahoma/Kansas border in vicinity of front that extends into Missouri, which may be somewhat effectively augmented by lingering early day convection. Moderate to locally strong buoyancy will exist within a moist environment, with MLCAPE likely to reach 2500-3000 J/kg. A considerable vertical veering of winds will exist through the lower/middle troposphere, with around 30 kt effective shear. Instances of severe hail and/or wind gusts could occur. ...Southern Maine... Clouds have lingered much of the morning with rather weak lapse rates noted in the 12z KGYX/Gray Maine observed sounding, but clearing is occurring from the west and a narrow zone of modest destabilization should occur this afternoon, within a very moist environment (lower/middle 70s F surface dewpoints) ahead of a cold front. Pending sufficient destabilization, a locally severe storm or two could occur, potentially with an absence of lightning, in the presence of long/semi-straight hodographs (highlighted by 45-50 kt winds 3-6 km AGL). ...Central/south-central portions of Illinois and Indiana... Ample low-level CAPE (100+ J/kg 0-km AGL) near the southward-shifting boundary could lead to some potential for funnels or perhaps even a brief non-supercell tornado this afternoon. Some of the storms could otherwise pose a risk for gusty winds, but the overall potential for organized severe storms is currently expected to remain low. ..Guyer/Wendt.. 07/11/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1145 AM CDT Thu Jul 11 2024 Valid 111630Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN ARIZONA... ...SUMMARY... Severe thunderstorm wind gusts are possible over parts of southern Arizona from mid-afternoon through early/mid-evening. ...Arizona... Widely scattered to scattered thunderstorms are expected to develop this afternoon over the Mogollon Rim, and smaller mountain ranges to the south. That will occur as strong insolation at those higher elevations preferentially removes MLCINH, in the presence of generally greater low-level moisture than previous days. Some strengthening of flow aloft is expected over this region on the southeast periphery of the upper anticyclone. This will support convective motion off the Rim (and small mountain ranges to its south), into strongly heated/deeply mixed boundary layers of the desert floor. Isolated strong-severe gusts are possible from the relatively early, more-discrete activity, and swaths of strong-severe gusts are possible as convection moves southwestward toward the international border. ...Northern High Plains... Isolated to widely scattered, high-based thunderstorms are expected to form near the lee trough, where both relatively maximized convergence and strong surface heating should contribute to enough lift for convective initiation. The main concern should be damaging to severe gusts, given the deeply mixed subcloud layer. Isolated severe hail also may occur, amidst enough deep-layer shear for some organized thunderstorms (effective-shear magnitudes of 30-40 kt). Lack of greater moisture and buoyancy will be a limiting factor for coverage and intensity of convection, which should diminish rapidly after sunset. ...Southeast Kansas/Southern Missouri... A few severe storms could develop today to the east-northeast of a surface wave near the Oklahoma/Kansas border in vicinity of front that extends into Missouri, which may be somewhat effectively augmented by lingering early day convection. Moderate to locally strong buoyancy will exist within a moist environment, with MLCAPE likely to reach 2500-3000 J/kg. A considerable vertical veering of winds will exist through the lower/middle troposphere, with around 30 kt effective shear. Instances of severe hail and/or wind gusts could occur. ...Southern Maine... Clouds have lingered much of the morning with rather weak lapse rates noted in the 12z KGYX/Gray Maine observed sounding, but clearing is occurring from the west and a narrow zone of modest destabilization should occur this afternoon, within a very moist environment (lower/middle 70s F surface dewpoints) ahead of a cold front. Pending sufficient destabilization, a locally severe storm or two could occur, potentially with an absence of lightning, in the presence of long/semi-straight hodographs (highlighted by 45-50 kt winds 3-6 km AGL). ...Central/south-central portions of Illinois and Indiana... Ample low-level CAPE (100+ J/kg 0-km AGL) near the southward-shifting boundary could lead to some potential for funnels or perhaps even a brief non-supercell tornado this afternoon. Some of the storms could otherwise pose a risk for gusty winds, but the overall potential for organized severe storms is currently expected to remain low. ..Guyer/Wendt.. 07/11/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1145 AM CDT Thu Jul 11 2024 Valid 111630Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN ARIZONA... ...SUMMARY... Severe thunderstorm wind gusts are possible over parts of southern Arizona from mid-afternoon through early/mid-evening. ...Arizona... Widely scattered to scattered thunderstorms are expected to develop this afternoon over the Mogollon Rim, and smaller mountain ranges to the south. That will occur as strong insolation at those higher elevations preferentially removes MLCINH, in the presence of generally greater low-level moisture than previous days. Some strengthening of flow aloft is expected over this region on the southeast periphery of the upper anticyclone. This will support convective motion off the Rim (and small mountain ranges to its south), into strongly heated/deeply mixed boundary layers of the desert floor. Isolated strong-severe gusts are possible from the relatively early, more-discrete activity, and swaths of strong-severe gusts are possible as convection moves southwestward toward the international border. ...Northern High Plains... Isolated to widely scattered, high-based thunderstorms are expected to form near the lee trough, where both relatively maximized convergence and strong surface heating should contribute to enough lift for convective initiation. The main concern should be damaging to severe gusts, given the deeply mixed subcloud layer. Isolated severe hail also may occur, amidst enough deep-layer shear for some organized thunderstorms (effective-shear magnitudes of 30-40 kt). Lack of greater moisture and buoyancy will be a limiting factor for coverage and intensity of convection, which should diminish rapidly after sunset. ...Southeast Kansas/Southern Missouri... A few severe storms could develop today to the east-northeast of a surface wave near the Oklahoma/Kansas border in vicinity of front that extends into Missouri, which may be somewhat effectively augmented by lingering early day convection. Moderate to locally strong buoyancy will exist within a moist environment, with MLCAPE likely to reach 2500-3000 J/kg. A considerable vertical veering of winds will exist through the lower/middle troposphere, with around 30 kt effective shear. Instances of severe hail and/or wind gusts could occur. ...Southern Maine... Clouds have lingered much of the morning with rather weak lapse rates noted in the 12z KGYX/Gray Maine observed sounding, but clearing is occurring from the west and a narrow zone of modest destabilization should occur this afternoon, within a very moist environment (lower/middle 70s F surface dewpoints) ahead of a cold front. Pending sufficient destabilization, a locally severe storm or two could occur, potentially with an absence of lightning, in the presence of long/semi-straight hodographs (highlighted by 45-50 kt winds 3-6 km AGL). ...Central/south-central portions of Illinois and Indiana... Ample low-level CAPE (100+ J/kg 0-km AGL) near the southward-shifting boundary could lead to some potential for funnels or perhaps even a brief non-supercell tornado this afternoon. Some of the storms could otherwise pose a risk for gusty winds, but the overall potential for organized severe storms is currently expected to remain low. ..Guyer/Wendt.. 07/11/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1145 AM CDT Thu Jul 11 2024 Valid 111630Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN ARIZONA... ...SUMMARY... Severe thunderstorm wind gusts are possible over parts of southern Arizona from mid-afternoon through early/mid-evening. ...Arizona... Widely scattered to scattered thunderstorms are expected to develop this afternoon over the Mogollon Rim, and smaller mountain ranges to the south. That will occur as strong insolation at those higher elevations preferentially removes MLCINH, in the presence of generally greater low-level moisture than previous days. Some strengthening of flow aloft is expected over this region on the southeast periphery of the upper anticyclone. This will support convective motion off the Rim (and small mountain ranges to its south), into strongly heated/deeply mixed boundary layers of the desert floor. Isolated strong-severe gusts are possible from the relatively early, more-discrete activity, and swaths of strong-severe gusts are possible as convection moves southwestward toward the international border. ...Northern High Plains... Isolated to widely scattered, high-based thunderstorms are expected to form near the lee trough, where both relatively maximized convergence and strong surface heating should contribute to enough lift for convective initiation. The main concern should be damaging to severe gusts, given the deeply mixed subcloud layer. Isolated severe hail also may occur, amidst enough deep-layer shear for some organized thunderstorms (effective-shear magnitudes of 30-40 kt). Lack of greater moisture and buoyancy will be a limiting factor for coverage and intensity of convection, which should diminish rapidly after sunset. ...Southeast Kansas/Southern Missouri... A few severe storms could develop today to the east-northeast of a surface wave near the Oklahoma/Kansas border in vicinity of front that extends into Missouri, which may be somewhat effectively augmented by lingering early day convection. Moderate to locally strong buoyancy will exist within a moist environment, with MLCAPE likely to reach 2500-3000 J/kg. A considerable vertical veering of winds will exist through the lower/middle troposphere, with around 30 kt effective shear. Instances of severe hail and/or wind gusts could occur. ...Southern Maine... Clouds have lingered much of the morning with rather weak lapse rates noted in the 12z KGYX/Gray Maine observed sounding, but clearing is occurring from the west and a narrow zone of modest destabilization should occur this afternoon, within a very moist environment (lower/middle 70s F surface dewpoints) ahead of a cold front. Pending sufficient destabilization, a locally severe storm or two could occur, potentially with an absence of lightning, in the presence of long/semi-straight hodographs (highlighted by 45-50 kt winds 3-6 km AGL). ...Central/south-central portions of Illinois and Indiana... Ample low-level CAPE (100+ J/kg 0-km AGL) near the southward-shifting boundary could lead to some potential for funnels or perhaps even a brief non-supercell tornado this afternoon. Some of the storms could otherwise pose a risk for gusty winds, but the overall potential for organized severe storms is currently expected to remain low. ..Guyer/Wendt.. 07/11/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1145 AM CDT Thu Jul 11 2024 Valid 111630Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN ARIZONA... ...SUMMARY... Severe thunderstorm wind gusts are possible over parts of southern Arizona from mid-afternoon through early/mid-evening. ...Arizona... Widely scattered to scattered thunderstorms are expected to develop this afternoon over the Mogollon Rim, and smaller mountain ranges to the south. That will occur as strong insolation at those higher elevations preferentially removes MLCINH, in the presence of generally greater low-level moisture than previous days. Some strengthening of flow aloft is expected over this region on the southeast periphery of the upper anticyclone. This will support convective motion off the Rim (and small mountain ranges to its south), into strongly heated/deeply mixed boundary layers of the desert floor. Isolated strong-severe gusts are possible from the relatively early, more-discrete activity, and swaths of strong-severe gusts are possible as convection moves southwestward toward the international border. ...Northern High Plains... Isolated to widely scattered, high-based thunderstorms are expected to form near the lee trough, where both relatively maximized convergence and strong surface heating should contribute to enough lift for convective initiation. The main concern should be damaging to severe gusts, given the deeply mixed subcloud layer. Isolated severe hail also may occur, amidst enough deep-layer shear for some organized thunderstorms (effective-shear magnitudes of 30-40 kt). Lack of greater moisture and buoyancy will be a limiting factor for coverage and intensity of convection, which should diminish rapidly after sunset. ...Southeast Kansas/Southern Missouri... A few severe storms could develop today to the east-northeast of a surface wave near the Oklahoma/Kansas border in vicinity of front that extends into Missouri, which may be somewhat effectively augmented by lingering early day convection. Moderate to locally strong buoyancy will exist within a moist environment, with MLCAPE likely to reach 2500-3000 J/kg. A considerable vertical veering of winds will exist through the lower/middle troposphere, with around 30 kt effective shear. Instances of severe hail and/or wind gusts could occur. ...Southern Maine... Clouds have lingered much of the morning with rather weak lapse rates noted in the 12z KGYX/Gray Maine observed sounding, but clearing is occurring from the west and a narrow zone of modest destabilization should occur this afternoon, within a very moist environment (lower/middle 70s F surface dewpoints) ahead of a cold front. Pending sufficient destabilization, a locally severe storm or two could occur, potentially with an absence of lightning, in the presence of long/semi-straight hodographs (highlighted by 45-50 kt winds 3-6 km AGL). ...Central/south-central portions of Illinois and Indiana... Ample low-level CAPE (100+ J/kg 0-km AGL) near the southward-shifting boundary could lead to some potential for funnels or perhaps even a brief non-supercell tornado this afternoon. Some of the storms could otherwise pose a risk for gusty winds, but the overall potential for organized severe storms is currently expected to remain low. ..Guyer/Wendt.. 07/11/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1145 AM CDT Thu Jul 11 2024 Valid 111630Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN ARIZONA... ...SUMMARY... Severe thunderstorm wind gusts are possible over parts of southern Arizona from mid-afternoon through early/mid-evening. ...Arizona... Widely scattered to scattered thunderstorms are expected to develop this afternoon over the Mogollon Rim, and smaller mountain ranges to the south. That will occur as strong insolation at those higher elevations preferentially removes MLCINH, in the presence of generally greater low-level moisture than previous days. Some strengthening of flow aloft is expected over this region on the southeast periphery of the upper anticyclone. This will support convective motion off the Rim (and small mountain ranges to its south), into strongly heated/deeply mixed boundary layers of the desert floor. Isolated strong-severe gusts are possible from the relatively early, more-discrete activity, and swaths of strong-severe gusts are possible as convection moves southwestward toward the international border. ...Northern High Plains... Isolated to widely scattered, high-based thunderstorms are expected to form near the lee trough, where both relatively maximized convergence and strong surface heating should contribute to enough lift for convective initiation. The main concern should be damaging to severe gusts, given the deeply mixed subcloud layer. Isolated severe hail also may occur, amidst enough deep-layer shear for some organized thunderstorms (effective-shear magnitudes of 30-40 kt). Lack of greater moisture and buoyancy will be a limiting factor for coverage and intensity of convection, which should diminish rapidly after sunset. ...Southeast Kansas/Southern Missouri... A few severe storms could develop today to the east-northeast of a surface wave near the Oklahoma/Kansas border in vicinity of front that extends into Missouri, which may be somewhat effectively augmented by lingering early day convection. Moderate to locally strong buoyancy will exist within a moist environment, with MLCAPE likely to reach 2500-3000 J/kg. A considerable vertical veering of winds will exist through the lower/middle troposphere, with around 30 kt effective shear. Instances of severe hail and/or wind gusts could occur. ...Southern Maine... Clouds have lingered much of the morning with rather weak lapse rates noted in the 12z KGYX/Gray Maine observed sounding, but clearing is occurring from the west and a narrow zone of modest destabilization should occur this afternoon, within a very moist environment (lower/middle 70s F surface dewpoints) ahead of a cold front. Pending sufficient destabilization, a locally severe storm or two could occur, potentially with an absence of lightning, in the presence of long/semi-straight hodographs (highlighted by 45-50 kt winds 3-6 km AGL). ...Central/south-central portions of Illinois and Indiana... Ample low-level CAPE (100+ J/kg 0-km AGL) near the southward-shifting boundary could lead to some potential for funnels or perhaps even a brief non-supercell tornado this afternoon. Some of the storms could otherwise pose a risk for gusty winds, but the overall potential for organized severe storms is currently expected to remain low. ..Guyer/Wendt.. 07/11/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0755 AM CDT Thu Jul 11 2024 Valid 111300Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF SOUTHERN ARIZONA... ...SUMMARY... Severe thunderstorm gusts are possible over parts of southern Arizona from midafternoon into early evening. ...Synopsis... In mid/upper levels, the overall pattern will change little through the period, with mean ridging in the West, and troughing over the Great Lakes and vicinity. The persistent anticyclone will remain over the Great Basin, with some deamplification of ridging to its north leading to more-zonal flow across the northern tier of states from WA-ND. A weak shortwave trough -- apparent in moisture-channel imagery over parts of central/eastern MT -- should move slowly east-southeastward across the northern High Plains today amid difluent flow. Meanwhile and downstream, a pronounced shortwave trough now over parts of WI/IL/IA should eject northeastward over the Upper Great Lakes and weaken, while smaller/upstream perturbations help to maintain the mean trough. Both the low/middle-level remains of TC Beryl, and a closely associated shortwave trough of midlatitude origins, should shear northeastward across southern QC, the lower St. Lawrence Valley, and northern New England, weakening considerably. At the surface, 11Z analysis showed a low near the NH/QC border with slow-moving, weakening cold front across western New England, the coastal Mid-Atlantic/Carolinas, southern GA, and FL Panhandle, becoming quasistationary along the northwestern Gulf Coast. This front should continue weakening near or just east of its present position through the period, over the Northeast, and also weaken over the Gulf Coast and southern Atlantic Coast States. Enough low-level shear exists over parts of ME today to support a conditional supercell potential, but strength/coverage/longevity are in question due to weakness of both instability and lift. Elsewhere, a lee trough analyzed on that chart over eastern parts of MT/WY/CO should remain over the central/northern High Plains today, with some eastward drift possible. ...AZ... Widely scattered to scattered thunderstorms are expected to develop this afternoon, over the Mogollon Rim and smaller mountain ranges to the south. That will occur as strong insolation at those higher elevations preferentially removes MLCINH, in the presence of generally greater low-level moisture than previous days. Some strengthening of flow aloft is expected over this region, around the southeastern rim of the anticyclone. This will support convective motion off the Rim (and small mountain ranges to its south), then atop well-heated/deeply mixed boundary layers of the desert floor. Isolated strong-severe gusts are possible from the relatively early, more-discrete activity. With the lower-elevation boundary layers being very deep (surface to around 600 mb), but enough moisture maintained through mixing to keep surface-based buoyancy (MLCAPE in the 500-1000 J/kg range), expect some aggregation of outflows with additional development atop those -- especially over southeastern AZ. The net result should be both translation and developmental propagation of convection southwestward to and across the international border, with swaths of strong-severe gusts possible. ...Northern High Plains... Isolated to widely scattered, high-based thunderstorms are expected to form near the lee trough, where both relatively maximized convergence and strong surface heating should contribute to enough lift for convective initiation. The main concern up and down the corridor should be damaging to severe gusts, given the deeply mixed subcloud layer and ample downdraft-acceleration opportunity that will afford. Isolated severe hail also may occur, amidst enough deep-layer shear for some organized thunderstorms (effective-shear magnitudes of 30-40 kt). Lack of greater moisture and buoyancy will be a limiting factor for coverage and intensity of convection, which should diminish rapidly after dark. ..Edwards/Bentley.. 07/11/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0755 AM CDT Thu Jul 11 2024 Valid 111300Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF SOUTHERN ARIZONA... ...SUMMARY... Severe thunderstorm gusts are possible over parts of southern Arizona from midafternoon into early evening. ...Synopsis... In mid/upper levels, the overall pattern will change little through the period, with mean ridging in the West, and troughing over the Great Lakes and vicinity. The persistent anticyclone will remain over the Great Basin, with some deamplification of ridging to its north leading to more-zonal flow across the northern tier of states from WA-ND. A weak shortwave trough -- apparent in moisture-channel imagery over parts of central/eastern MT -- should move slowly east-southeastward across the northern High Plains today amid difluent flow. Meanwhile and downstream, a pronounced shortwave trough now over parts of WI/IL/IA should eject northeastward over the Upper Great Lakes and weaken, while smaller/upstream perturbations help to maintain the mean trough. Both the low/middle-level remains of TC Beryl, and a closely associated shortwave trough of midlatitude origins, should shear northeastward across southern QC, the lower St. Lawrence Valley, and northern New England, weakening considerably. At the surface, 11Z analysis showed a low near the NH/QC border with slow-moving, weakening cold front across western New England, the coastal Mid-Atlantic/Carolinas, southern GA, and FL Panhandle, becoming quasistationary along the northwestern Gulf Coast. This front should continue weakening near or just east of its present position through the period, over the Northeast, and also weaken over the Gulf Coast and southern Atlantic Coast States. Enough low-level shear exists over parts of ME today to support a conditional supercell potential, but strength/coverage/longevity are in question due to weakness of both instability and lift. Elsewhere, a lee trough analyzed on that chart over eastern parts of MT/WY/CO should remain over the central/northern High Plains today, with some eastward drift possible. ...AZ... Widely scattered to scattered thunderstorms are expected to develop this afternoon, over the Mogollon Rim and smaller mountain ranges to the south. That will occur as strong insolation at those higher elevations preferentially removes MLCINH, in the presence of generally greater low-level moisture than previous days. Some strengthening of flow aloft is expected over this region, around the southeastern rim of the anticyclone. This will support convective motion off the Rim (and small mountain ranges to its south), then atop well-heated/deeply mixed boundary layers of the desert floor. Isolated strong-severe gusts are possible from the relatively early, more-discrete activity. With the lower-elevation boundary layers being very deep (surface to around 600 mb), but enough moisture maintained through mixing to keep surface-based buoyancy (MLCAPE in the 500-1000 J/kg range), expect some aggregation of outflows with additional development atop those -- especially over southeastern AZ. The net result should be both translation and developmental propagation of convection southwestward to and across the international border, with swaths of strong-severe gusts possible. ...Northern High Plains... Isolated to widely scattered, high-based thunderstorms are expected to form near the lee trough, where both relatively maximized convergence and strong surface heating should contribute to enough lift for convective initiation. The main concern up and down the corridor should be damaging to severe gusts, given the deeply mixed subcloud layer and ample downdraft-acceleration opportunity that will afford. Isolated severe hail also may occur, amidst enough deep-layer shear for some organized thunderstorms (effective-shear magnitudes of 30-40 kt). Lack of greater moisture and buoyancy will be a limiting factor for coverage and intensity of convection, which should diminish rapidly after dark. ..Edwards/Bentley.. 07/11/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0755 AM CDT Thu Jul 11 2024 Valid 111300Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF SOUTHERN ARIZONA... ...SUMMARY... Severe thunderstorm gusts are possible over parts of southern Arizona from midafternoon into early evening. ...Synopsis... In mid/upper levels, the overall pattern will change little through the period, with mean ridging in the West, and troughing over the Great Lakes and vicinity. The persistent anticyclone will remain over the Great Basin, with some deamplification of ridging to its north leading to more-zonal flow across the northern tier of states from WA-ND. A weak shortwave trough -- apparent in moisture-channel imagery over parts of central/eastern MT -- should move slowly east-southeastward across the northern High Plains today amid difluent flow. Meanwhile and downstream, a pronounced shortwave trough now over parts of WI/IL/IA should eject northeastward over the Upper Great Lakes and weaken, while smaller/upstream perturbations help to maintain the mean trough. Both the low/middle-level remains of TC Beryl, and a closely associated shortwave trough of midlatitude origins, should shear northeastward across southern QC, the lower St. Lawrence Valley, and northern New England, weakening considerably. At the surface, 11Z analysis showed a low near the NH/QC border with slow-moving, weakening cold front across western New England, the coastal Mid-Atlantic/Carolinas, southern GA, and FL Panhandle, becoming quasistationary along the northwestern Gulf Coast. This front should continue weakening near or just east of its present position through the period, over the Northeast, and also weaken over the Gulf Coast and southern Atlantic Coast States. Enough low-level shear exists over parts of ME today to support a conditional supercell potential, but strength/coverage/longevity are in question due to weakness of both instability and lift. Elsewhere, a lee trough analyzed on that chart over eastern parts of MT/WY/CO should remain over the central/northern High Plains today, with some eastward drift possible. ...AZ... Widely scattered to scattered thunderstorms are expected to develop this afternoon, over the Mogollon Rim and smaller mountain ranges to the south. That will occur as strong insolation at those higher elevations preferentially removes MLCINH, in the presence of generally greater low-level moisture than previous days. Some strengthening of flow aloft is expected over this region, around the southeastern rim of the anticyclone. This will support convective motion off the Rim (and small mountain ranges to its south), then atop well-heated/deeply mixed boundary layers of the desert floor. Isolated strong-severe gusts are possible from the relatively early, more-discrete activity. With the lower-elevation boundary layers being very deep (surface to around 600 mb), but enough moisture maintained through mixing to keep surface-based buoyancy (MLCAPE in the 500-1000 J/kg range), expect some aggregation of outflows with additional development atop those -- especially over southeastern AZ. The net result should be both translation and developmental propagation of convection southwestward to and across the international border, with swaths of strong-severe gusts possible. ...Northern High Plains... Isolated to widely scattered, high-based thunderstorms are expected to form near the lee trough, where both relatively maximized convergence and strong surface heating should contribute to enough lift for convective initiation. The main concern up and down the corridor should be damaging to severe gusts, given the deeply mixed subcloud layer and ample downdraft-acceleration opportunity that will afford. Isolated severe hail also may occur, amidst enough deep-layer shear for some organized thunderstorms (effective-shear magnitudes of 30-40 kt). Lack of greater moisture and buoyancy will be a limiting factor for coverage and intensity of convection, which should diminish rapidly after dark. ..Edwards/Bentley.. 07/11/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0755 AM CDT Thu Jul 11 2024 Valid 111300Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF SOUTHERN ARIZONA... ...SUMMARY... Severe thunderstorm gusts are possible over parts of southern Arizona from midafternoon into early evening. ...Synopsis... In mid/upper levels, the overall pattern will change little through the period, with mean ridging in the West, and troughing over the Great Lakes and vicinity. The persistent anticyclone will remain over the Great Basin, with some deamplification of ridging to its north leading to more-zonal flow across the northern tier of states from WA-ND. A weak shortwave trough -- apparent in moisture-channel imagery over parts of central/eastern MT -- should move slowly east-southeastward across the northern High Plains today amid difluent flow. Meanwhile and downstream, a pronounced shortwave trough now over parts of WI/IL/IA should eject northeastward over the Upper Great Lakes and weaken, while smaller/upstream perturbations help to maintain the mean trough. Both the low/middle-level remains of TC Beryl, and a closely associated shortwave trough of midlatitude origins, should shear northeastward across southern QC, the lower St. Lawrence Valley, and northern New England, weakening considerably. At the surface, 11Z analysis showed a low near the NH/QC border with slow-moving, weakening cold front across western New England, the coastal Mid-Atlantic/Carolinas, southern GA, and FL Panhandle, becoming quasistationary along the northwestern Gulf Coast. This front should continue weakening near or just east of its present position through the period, over the Northeast, and also weaken over the Gulf Coast and southern Atlantic Coast States. Enough low-level shear exists over parts of ME today to support a conditional supercell potential, but strength/coverage/longevity are in question due to weakness of both instability and lift. Elsewhere, a lee trough analyzed on that chart over eastern parts of MT/WY/CO should remain over the central/northern High Plains today, with some eastward drift possible. ...AZ... Widely scattered to scattered thunderstorms are expected to develop this afternoon, over the Mogollon Rim and smaller mountain ranges to the south. That will occur as strong insolation at those higher elevations preferentially removes MLCINH, in the presence of generally greater low-level moisture than previous days. Some strengthening of flow aloft is expected over this region, around the southeastern rim of the anticyclone. This will support convective motion off the Rim (and small mountain ranges to its south), then atop well-heated/deeply mixed boundary layers of the desert floor. Isolated strong-severe gusts are possible from the relatively early, more-discrete activity. With the lower-elevation boundary layers being very deep (surface to around 600 mb), but enough moisture maintained through mixing to keep surface-based buoyancy (MLCAPE in the 500-1000 J/kg range), expect some aggregation of outflows with additional development atop those -- especially over southeastern AZ. The net result should be both translation and developmental propagation of convection southwestward to and across the international border, with swaths of strong-severe gusts possible. ...Northern High Plains... Isolated to widely scattered, high-based thunderstorms are expected to form near the lee trough, where both relatively maximized convergence and strong surface heating should contribute to enough lift for convective initiation. The main concern up and down the corridor should be damaging to severe gusts, given the deeply mixed subcloud layer and ample downdraft-acceleration opportunity that will afford. Isolated severe hail also may occur, amidst enough deep-layer shear for some organized thunderstorms (effective-shear magnitudes of 30-40 kt). Lack of greater moisture and buoyancy will be a limiting factor for coverage and intensity of convection, which should diminish rapidly after dark. ..Edwards/Bentley.. 07/11/2024 Read more