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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CDT Sun Jul 28 2024 Valid 281200Z - 291200Z ...Synopsis... A midlevel shortwave trough will advance eastward across the northern Rockies and adjacent High Plains today, while a large-scale ridge remains centered over the southern Rockies/Southwest. Between these two features, a belt of moderate (30-40 kt) midlevel flow will overspread the Central Great Basin. ...Central Great Basin... Ample diurnal heating from southern NV east-northeastward across southern/central UT into south-central WY will yield deep boundary-layer mixing into the moderate flow aloft. As a result, 5-10 percent minimum RH will overlap 15-20 mph sustained southwesterly surface winds during the afternoon. Given modestly receptive fuels through this corridor, elevated to locally critical fire-weather conditions are expected. ...Northern Rockies and adjacent High Plains... Large-scale ascent preceding the midlevel shortwave trough will intercept a midlevel moisture plume, favoring isolated to widely scattered high-based thunderstorms from the afternoon into the evening. 0.5-0.75 inch PW and quick storm motions will contribute to mostly dry thunderstorms, capable of lightning-induced ignitions over dry fuels. Strong/erratic outflow winds could also accompany this activity. ..Weinman.. 07/28/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CDT Sun Jul 28 2024 Valid 281200Z - 291200Z ...Synopsis... A midlevel shortwave trough will advance eastward across the northern Rockies and adjacent High Plains today, while a large-scale ridge remains centered over the southern Rockies/Southwest. Between these two features, a belt of moderate (30-40 kt) midlevel flow will overspread the Central Great Basin. ...Central Great Basin... Ample diurnal heating from southern NV east-northeastward across southern/central UT into south-central WY will yield deep boundary-layer mixing into the moderate flow aloft. As a result, 5-10 percent minimum RH will overlap 15-20 mph sustained southwesterly surface winds during the afternoon. Given modestly receptive fuels through this corridor, elevated to locally critical fire-weather conditions are expected. ...Northern Rockies and adjacent High Plains... Large-scale ascent preceding the midlevel shortwave trough will intercept a midlevel moisture plume, favoring isolated to widely scattered high-based thunderstorms from the afternoon into the evening. 0.5-0.75 inch PW and quick storm motions will contribute to mostly dry thunderstorms, capable of lightning-induced ignitions over dry fuels. Strong/erratic outflow winds could also accompany this activity. ..Weinman.. 07/28/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CDT Sun Jul 28 2024 Valid 281200Z - 291200Z ...Synopsis... A midlevel shortwave trough will advance eastward across the northern Rockies and adjacent High Plains today, while a large-scale ridge remains centered over the southern Rockies/Southwest. Between these two features, a belt of moderate (30-40 kt) midlevel flow will overspread the Central Great Basin. ...Central Great Basin... Ample diurnal heating from southern NV east-northeastward across southern/central UT into south-central WY will yield deep boundary-layer mixing into the moderate flow aloft. As a result, 5-10 percent minimum RH will overlap 15-20 mph sustained southwesterly surface winds during the afternoon. Given modestly receptive fuels through this corridor, elevated to locally critical fire-weather conditions are expected. ...Northern Rockies and adjacent High Plains... Large-scale ascent preceding the midlevel shortwave trough will intercept a midlevel moisture plume, favoring isolated to widely scattered high-based thunderstorms from the afternoon into the evening. 0.5-0.75 inch PW and quick storm motions will contribute to mostly dry thunderstorms, capable of lightning-induced ignitions over dry fuels. Strong/erratic outflow winds could also accompany this activity. ..Weinman.. 07/28/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CDT Sun Jul 28 2024 Valid 281200Z - 291200Z ...Synopsis... A midlevel shortwave trough will advance eastward across the northern Rockies and adjacent High Plains today, while a large-scale ridge remains centered over the southern Rockies/Southwest. Between these two features, a belt of moderate (30-40 kt) midlevel flow will overspread the Central Great Basin. ...Central Great Basin... Ample diurnal heating from southern NV east-northeastward across southern/central UT into south-central WY will yield deep boundary-layer mixing into the moderate flow aloft. As a result, 5-10 percent minimum RH will overlap 15-20 mph sustained southwesterly surface winds during the afternoon. Given modestly receptive fuels through this corridor, elevated to locally critical fire-weather conditions are expected. ...Northern Rockies and adjacent High Plains... Large-scale ascent preceding the midlevel shortwave trough will intercept a midlevel moisture plume, favoring isolated to widely scattered high-based thunderstorms from the afternoon into the evening. 0.5-0.75 inch PW and quick storm motions will contribute to mostly dry thunderstorms, capable of lightning-induced ignitions over dry fuels. Strong/erratic outflow winds could also accompany this activity. ..Weinman.. 07/28/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sun Jul 28 2024 Valid 291200Z - 301200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN PLAINS AND THE MIDWEST... ...SUMMARY... Scattered strong to severe storms are possible in portions of the Midwest and the northern Plains on Monday. ...Synopsis... A broad upper-level ridge will be centered over the central CONUS on Monday with a trough near the West Coast and a closed low near New England. Several weak mid-level shortwave troughs will move through the flow and may be the trigger for strong to severe thunderstorm activity. A broad surface trough will extend from the Upper Midwest to the central Plains with a very moist airmass east of this surface trough. ...Northern Plains... A mid-level shortwave trough will cross the Dakotas during the day Monday and lead to increasing ascent amid a moderately unstable environment. 35 to 50 knots of mid-level flow will accompany this mid-level trough and lead to 35 to 45 knots of effective shear. Considerable uncertainty remains with the degree of destabilization across the Dakotas. Forecast soundings show surface dewpoints ranging from the mid 50s to the mid 60s F which will significantly impact the degree of instability within the warm sector and likely impact the coverage and intensity of the severe weather threat. Nonetheless, the ascent associated with the shortwave trough and an uncapped environment should result in storm development Monday afternoon in the Dakotas. Moderate shear and steep lapse rates will support a threat for large hail (potentially 2+ inch if greater instability scenarios verify) and the deeply mixed boundary layer will support a severe wind threat. The severe weather threat is expected to wane shortly after sunset given increasing inhibition and the low-level jet being displaced well southeast. ...Midwest... A MCS/cluster of storms will likely be ongoing in the vicinity of eastern IA/MO and western Illinois on Monday morning. The low-level jet is expected to weaken during the morning hours which will likely lead to the demise of the morning convection. In its wake, significant destabilization is anticipated with a moderate to strongly unstable airmass expected. Weak height rises will likely be somewhat counteracted by continued weak low-level isentropic ascent which may be sufficient for storm development along the remnant outflow Monday afternoon/evening. Uncertainty in exact storm evolution remains high, but there is at least some potential for upscale growth into a MCS, particularly across Illinois, which may necessitate greater severe weather probabilities. ..Bentley.. 07/28/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sun Jul 28 2024 Valid 291200Z - 301200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN PLAINS AND THE MIDWEST... ...SUMMARY... Scattered strong to severe storms are possible in portions of the Midwest and the northern Plains on Monday. ...Synopsis... A broad upper-level ridge will be centered over the central CONUS on Monday with a trough near the West Coast and a closed low near New England. Several weak mid-level shortwave troughs will move through the flow and may be the trigger for strong to severe thunderstorm activity. A broad surface trough will extend from the Upper Midwest to the central Plains with a very moist airmass east of this surface trough. ...Northern Plains... A mid-level shortwave trough will cross the Dakotas during the day Monday and lead to increasing ascent amid a moderately unstable environment. 35 to 50 knots of mid-level flow will accompany this mid-level trough and lead to 35 to 45 knots of effective shear. Considerable uncertainty remains with the degree of destabilization across the Dakotas. Forecast soundings show surface dewpoints ranging from the mid 50s to the mid 60s F which will significantly impact the degree of instability within the warm sector and likely impact the coverage and intensity of the severe weather threat. Nonetheless, the ascent associated with the shortwave trough and an uncapped environment should result in storm development Monday afternoon in the Dakotas. Moderate shear and steep lapse rates will support a threat for large hail (potentially 2+ inch if greater instability scenarios verify) and the deeply mixed boundary layer will support a severe wind threat. The severe weather threat is expected to wane shortly after sunset given increasing inhibition and the low-level jet being displaced well southeast. ...Midwest... A MCS/cluster of storms will likely be ongoing in the vicinity of eastern IA/MO and western Illinois on Monday morning. The low-level jet is expected to weaken during the morning hours which will likely lead to the demise of the morning convection. In its wake, significant destabilization is anticipated with a moderate to strongly unstable airmass expected. Weak height rises will likely be somewhat counteracted by continued weak low-level isentropic ascent which may be sufficient for storm development along the remnant outflow Monday afternoon/evening. Uncertainty in exact storm evolution remains high, but there is at least some potential for upscale growth into a MCS, particularly across Illinois, which may necessitate greater severe weather probabilities. ..Bentley.. 07/28/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sun Jul 28 2024 Valid 291200Z - 301200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN PLAINS AND THE MIDWEST... ...SUMMARY... Scattered strong to severe storms are possible in portions of the Midwest and the northern Plains on Monday. ...Synopsis... A broad upper-level ridge will be centered over the central CONUS on Monday with a trough near the West Coast and a closed low near New England. Several weak mid-level shortwave troughs will move through the flow and may be the trigger for strong to severe thunderstorm activity. A broad surface trough will extend from the Upper Midwest to the central Plains with a very moist airmass east of this surface trough. ...Northern Plains... A mid-level shortwave trough will cross the Dakotas during the day Monday and lead to increasing ascent amid a moderately unstable environment. 35 to 50 knots of mid-level flow will accompany this mid-level trough and lead to 35 to 45 knots of effective shear. Considerable uncertainty remains with the degree of destabilization across the Dakotas. Forecast soundings show surface dewpoints ranging from the mid 50s to the mid 60s F which will significantly impact the degree of instability within the warm sector and likely impact the coverage and intensity of the severe weather threat. Nonetheless, the ascent associated with the shortwave trough and an uncapped environment should result in storm development Monday afternoon in the Dakotas. Moderate shear and steep lapse rates will support a threat for large hail (potentially 2+ inch if greater instability scenarios verify) and the deeply mixed boundary layer will support a severe wind threat. The severe weather threat is expected to wane shortly after sunset given increasing inhibition and the low-level jet being displaced well southeast. ...Midwest... A MCS/cluster of storms will likely be ongoing in the vicinity of eastern IA/MO and western Illinois on Monday morning. The low-level jet is expected to weaken during the morning hours which will likely lead to the demise of the morning convection. In its wake, significant destabilization is anticipated with a moderate to strongly unstable airmass expected. Weak height rises will likely be somewhat counteracted by continued weak low-level isentropic ascent which may be sufficient for storm development along the remnant outflow Monday afternoon/evening. Uncertainty in exact storm evolution remains high, but there is at least some potential for upscale growth into a MCS, particularly across Illinois, which may necessitate greater severe weather probabilities. ..Bentley.. 07/28/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sun Jul 28 2024 Valid 291200Z - 301200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN PLAINS AND THE MIDWEST... ...SUMMARY... Scattered strong to severe storms are possible in portions of the Midwest and the northern Plains on Monday. ...Synopsis... A broad upper-level ridge will be centered over the central CONUS on Monday with a trough near the West Coast and a closed low near New England. Several weak mid-level shortwave troughs will move through the flow and may be the trigger for strong to severe thunderstorm activity. A broad surface trough will extend from the Upper Midwest to the central Plains with a very moist airmass east of this surface trough. ...Northern Plains... A mid-level shortwave trough will cross the Dakotas during the day Monday and lead to increasing ascent amid a moderately unstable environment. 35 to 50 knots of mid-level flow will accompany this mid-level trough and lead to 35 to 45 knots of effective shear. Considerable uncertainty remains with the degree of destabilization across the Dakotas. Forecast soundings show surface dewpoints ranging from the mid 50s to the mid 60s F which will significantly impact the degree of instability within the warm sector and likely impact the coverage and intensity of the severe weather threat. Nonetheless, the ascent associated with the shortwave trough and an uncapped environment should result in storm development Monday afternoon in the Dakotas. Moderate shear and steep lapse rates will support a threat for large hail (potentially 2+ inch if greater instability scenarios verify) and the deeply mixed boundary layer will support a severe wind threat. The severe weather threat is expected to wane shortly after sunset given increasing inhibition and the low-level jet being displaced well southeast. ...Midwest... A MCS/cluster of storms will likely be ongoing in the vicinity of eastern IA/MO and western Illinois on Monday morning. The low-level jet is expected to weaken during the morning hours which will likely lead to the demise of the morning convection. In its wake, significant destabilization is anticipated with a moderate to strongly unstable airmass expected. Weak height rises will likely be somewhat counteracted by continued weak low-level isentropic ascent which may be sufficient for storm development along the remnant outflow Monday afternoon/evening. Uncertainty in exact storm evolution remains high, but there is at least some potential for upscale growth into a MCS, particularly across Illinois, which may necessitate greater severe weather probabilities. ..Bentley.. 07/28/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sun Jul 28 2024 Valid 291200Z - 301200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN PLAINS AND THE MIDWEST... ...SUMMARY... Scattered strong to severe storms are possible in portions of the Midwest and the northern Plains on Monday. ...Synopsis... A broad upper-level ridge will be centered over the central CONUS on Monday with a trough near the West Coast and a closed low near New England. Several weak mid-level shortwave troughs will move through the flow and may be the trigger for strong to severe thunderstorm activity. A broad surface trough will extend from the Upper Midwest to the central Plains with a very moist airmass east of this surface trough. ...Northern Plains... A mid-level shortwave trough will cross the Dakotas during the day Monday and lead to increasing ascent amid a moderately unstable environment. 35 to 50 knots of mid-level flow will accompany this mid-level trough and lead to 35 to 45 knots of effective shear. Considerable uncertainty remains with the degree of destabilization across the Dakotas. Forecast soundings show surface dewpoints ranging from the mid 50s to the mid 60s F which will significantly impact the degree of instability within the warm sector and likely impact the coverage and intensity of the severe weather threat. Nonetheless, the ascent associated with the shortwave trough and an uncapped environment should result in storm development Monday afternoon in the Dakotas. Moderate shear and steep lapse rates will support a threat for large hail (potentially 2+ inch if greater instability scenarios verify) and the deeply mixed boundary layer will support a severe wind threat. The severe weather threat is expected to wane shortly after sunset given increasing inhibition and the low-level jet being displaced well southeast. ...Midwest... A MCS/cluster of storms will likely be ongoing in the vicinity of eastern IA/MO and western Illinois on Monday morning. The low-level jet is expected to weaken during the morning hours which will likely lead to the demise of the morning convection. In its wake, significant destabilization is anticipated with a moderate to strongly unstable airmass expected. Weak height rises will likely be somewhat counteracted by continued weak low-level isentropic ascent which may be sufficient for storm development along the remnant outflow Monday afternoon/evening. Uncertainty in exact storm evolution remains high, but there is at least some potential for upscale growth into a MCS, particularly across Illinois, which may necessitate greater severe weather probabilities. ..Bentley.. 07/28/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Sun Jul 28 2024 Valid 281200Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN AND CENTRAL PLAINS... ...SUMMARY... Scattered strong to severe thunderstorms are expected across parts of the central and northern Plains this afternoon into tonight. ...Synopsis... Multiple midlevel shortwave troughs, some convectively enhanced, are forecast to move across parts of the central and northern Great Plains later today into tonight. One surface low is forecast to gradually deepen across western SD, in the vicinity of a front that may become nearly stationary during the afternoon. Another surface low may develop near a surface trough across western KS. Very steep midlevel lapse rates will support moderate to strong buoyancy across a broad region of the central/northern Plains into parts of the upper Midwest. Storm evolution could be rather complex later today, with multiple potential areas for diurnal development and intensification, and some potential for one or more corridors of severe/damaging gusts, along with some threat for hail and possibly a tornado or two. ...SD and vicinity... Widely scattered thunderstorm development is expected this afternoon across parts of western SD, near/north of the front and in the vicinity of the surface low. 30-40 kt of midlevel flow atop low-level easterlies north of the boundary will provide sufficient deep-layer shear for storm organization, and a couple supercells will be possible initially. Hail and isolated severe gusts will be a threat with the initial discrete development. Outflow consolidation could support development of an upscale-growing cluster (as depicted by several HREF members), which could propagate quickly east-southeastward toward southeast SD and vicinity, with a threat of severe gusts potentially exceeding 75 mph. Greater unconditional wind probabilities may eventually be needed if confidence increases regarding this scenario. ...Central High Plains... While large-scale forcing/ascent will be somewhat weaker with southward extent, strong heating and removal of MLCINH will support at least isolated storm development from western/central NE into western KS, and potentially into northeast CO. Moderate to strong buoyancy, steep lapse rates, and moderate deep-layer shear will support a conditional risk of severe storms (including supercell potential) with any diurnal development in this region. Storm coverage remains uncertain, but the environment will conditionally support potential for both severe gusts and hail. ...Eastern NE into IA/MO... A potential MCV evolving from overnight convection across western/central NE will move eastward through the day. Some guidance depicts diurnal storm development in the vicinity of this feature, somewhere from eastern NE into western IA. Should this occur, strong buoyancy and sufficient deep-layer shear could support at least an isolated severe threat, with some potential for upscale growth into a southeastward-moving cluster. Even if substantial diurnal development does not occur, an increasing low-level jet could support increasing storm coverage across parts of IA/MO later this evening into the overnight, which could be accompanied by a threat for isolated strong/damaging gusts and/or hail. ...Southwest into northeast MN... In the wake of potential elevated convection during the morning, scattered thunderstorms are expected along/ahead of the front during the afternoon across parts of MN. A notable weakness in midlevel flow will tend to limit deep-layer shear and storm organization across the region, but MLCAPE increasing above 2000 J/kg and some modest enhancement to low-level flow could support localized damaging winds, and perhaps some hail with the strongest updrafts. ...Parts of MT/WY... Relatively high-based convection is expected to develop across parts of western/central WY into southern MT, in advance of a shortwave trough moving eastward out of the Pacific Northwest. A couple stronger outflow-driven cells/clusters will be possible, with an attendant threat for isolated severe gusts. ...MS/AL/TN... Rather widespread convection is expected later today from parts of the Ohio Valley into the Southeast, in association with a mid/upper-level trough moving northeastward out of the Ozarks vicinity. Somewhat stronger heating and midlevel flow along the southern periphery of this trough could support a few strong storms across parts of MS/AL/TN, but with generally modest deep-layer shear and weak midlevel lapse rates, the potential for any organized severe threat across this region remains uncertain. ..Dean/Weinman.. 07/28/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Sun Jul 28 2024 Valid 281200Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN AND CENTRAL PLAINS... ...SUMMARY... Scattered strong to severe thunderstorms are expected across parts of the central and northern Plains this afternoon into tonight. ...Synopsis... Multiple midlevel shortwave troughs, some convectively enhanced, are forecast to move across parts of the central and northern Great Plains later today into tonight. One surface low is forecast to gradually deepen across western SD, in the vicinity of a front that may become nearly stationary during the afternoon. Another surface low may develop near a surface trough across western KS. Very steep midlevel lapse rates will support moderate to strong buoyancy across a broad region of the central/northern Plains into parts of the upper Midwest. Storm evolution could be rather complex later today, with multiple potential areas for diurnal development and intensification, and some potential for one or more corridors of severe/damaging gusts, along with some threat for hail and possibly a tornado or two. ...SD and vicinity... Widely scattered thunderstorm development is expected this afternoon across parts of western SD, near/north of the front and in the vicinity of the surface low. 30-40 kt of midlevel flow atop low-level easterlies north of the boundary will provide sufficient deep-layer shear for storm organization, and a couple supercells will be possible initially. Hail and isolated severe gusts will be a threat with the initial discrete development. Outflow consolidation could support development of an upscale-growing cluster (as depicted by several HREF members), which could propagate quickly east-southeastward toward southeast SD and vicinity, with a threat of severe gusts potentially exceeding 75 mph. Greater unconditional wind probabilities may eventually be needed if confidence increases regarding this scenario. ...Central High Plains... While large-scale forcing/ascent will be somewhat weaker with southward extent, strong heating and removal of MLCINH will support at least isolated storm development from western/central NE into western KS, and potentially into northeast CO. Moderate to strong buoyancy, steep lapse rates, and moderate deep-layer shear will support a conditional risk of severe storms (including supercell potential) with any diurnal development in this region. Storm coverage remains uncertain, but the environment will conditionally support potential for both severe gusts and hail. ...Eastern NE into IA/MO... A potential MCV evolving from overnight convection across western/central NE will move eastward through the day. Some guidance depicts diurnal storm development in the vicinity of this feature, somewhere from eastern NE into western IA. Should this occur, strong buoyancy and sufficient deep-layer shear could support at least an isolated severe threat, with some potential for upscale growth into a southeastward-moving cluster. Even if substantial diurnal development does not occur, an increasing low-level jet could support increasing storm coverage across parts of IA/MO later this evening into the overnight, which could be accompanied by a threat for isolated strong/damaging gusts and/or hail. ...Southwest into northeast MN... In the wake of potential elevated convection during the morning, scattered thunderstorms are expected along/ahead of the front during the afternoon across parts of MN. A notable weakness in midlevel flow will tend to limit deep-layer shear and storm organization across the region, but MLCAPE increasing above 2000 J/kg and some modest enhancement to low-level flow could support localized damaging winds, and perhaps some hail with the strongest updrafts. ...Parts of MT/WY... Relatively high-based convection is expected to develop across parts of western/central WY into southern MT, in advance of a shortwave trough moving eastward out of the Pacific Northwest. A couple stronger outflow-driven cells/clusters will be possible, with an attendant threat for isolated severe gusts. ...MS/AL/TN... Rather widespread convection is expected later today from parts of the Ohio Valley into the Southeast, in association with a mid/upper-level trough moving northeastward out of the Ozarks vicinity. Somewhat stronger heating and midlevel flow along the southern periphery of this trough could support a few strong storms across parts of MS/AL/TN, but with generally modest deep-layer shear and weak midlevel lapse rates, the potential for any organized severe threat across this region remains uncertain. ..Dean/Weinman.. 07/28/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Sun Jul 28 2024 Valid 281200Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN AND CENTRAL PLAINS... ...SUMMARY... Scattered strong to severe thunderstorms are expected across parts of the central and northern Plains this afternoon into tonight. ...Synopsis... Multiple midlevel shortwave troughs, some convectively enhanced, are forecast to move across parts of the central and northern Great Plains later today into tonight. One surface low is forecast to gradually deepen across western SD, in the vicinity of a front that may become nearly stationary during the afternoon. Another surface low may develop near a surface trough across western KS. Very steep midlevel lapse rates will support moderate to strong buoyancy across a broad region of the central/northern Plains into parts of the upper Midwest. Storm evolution could be rather complex later today, with multiple potential areas for diurnal development and intensification, and some potential for one or more corridors of severe/damaging gusts, along with some threat for hail and possibly a tornado or two. ...SD and vicinity... Widely scattered thunderstorm development is expected this afternoon across parts of western SD, near/north of the front and in the vicinity of the surface low. 30-40 kt of midlevel flow atop low-level easterlies north of the boundary will provide sufficient deep-layer shear for storm organization, and a couple supercells will be possible initially. Hail and isolated severe gusts will be a threat with the initial discrete development. Outflow consolidation could support development of an upscale-growing cluster (as depicted by several HREF members), which could propagate quickly east-southeastward toward southeast SD and vicinity, with a threat of severe gusts potentially exceeding 75 mph. Greater unconditional wind probabilities may eventually be needed if confidence increases regarding this scenario. ...Central High Plains... While large-scale forcing/ascent will be somewhat weaker with southward extent, strong heating and removal of MLCINH will support at least isolated storm development from western/central NE into western KS, and potentially into northeast CO. Moderate to strong buoyancy, steep lapse rates, and moderate deep-layer shear will support a conditional risk of severe storms (including supercell potential) with any diurnal development in this region. Storm coverage remains uncertain, but the environment will conditionally support potential for both severe gusts and hail. ...Eastern NE into IA/MO... A potential MCV evolving from overnight convection across western/central NE will move eastward through the day. Some guidance depicts diurnal storm development in the vicinity of this feature, somewhere from eastern NE into western IA. Should this occur, strong buoyancy and sufficient deep-layer shear could support at least an isolated severe threat, with some potential for upscale growth into a southeastward-moving cluster. Even if substantial diurnal development does not occur, an increasing low-level jet could support increasing storm coverage across parts of IA/MO later this evening into the overnight, which could be accompanied by a threat for isolated strong/damaging gusts and/or hail. ...Southwest into northeast MN... In the wake of potential elevated convection during the morning, scattered thunderstorms are expected along/ahead of the front during the afternoon across parts of MN. A notable weakness in midlevel flow will tend to limit deep-layer shear and storm organization across the region, but MLCAPE increasing above 2000 J/kg and some modest enhancement to low-level flow could support localized damaging winds, and perhaps some hail with the strongest updrafts. ...Parts of MT/WY... Relatively high-based convection is expected to develop across parts of western/central WY into southern MT, in advance of a shortwave trough moving eastward out of the Pacific Northwest. A couple stronger outflow-driven cells/clusters will be possible, with an attendant threat for isolated severe gusts. ...MS/AL/TN... Rather widespread convection is expected later today from parts of the Ohio Valley into the Southeast, in association with a mid/upper-level trough moving northeastward out of the Ozarks vicinity. Somewhat stronger heating and midlevel flow along the southern periphery of this trough could support a few strong storms across parts of MS/AL/TN, but with generally modest deep-layer shear and weak midlevel lapse rates, the potential for any organized severe threat across this region remains uncertain. ..Dean/Weinman.. 07/28/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Sun Jul 28 2024 Valid 281200Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN AND CENTRAL PLAINS... ...SUMMARY... Scattered strong to severe thunderstorms are expected across parts of the central and northern Plains this afternoon into tonight. ...Synopsis... Multiple midlevel shortwave troughs, some convectively enhanced, are forecast to move across parts of the central and northern Great Plains later today into tonight. One surface low is forecast to gradually deepen across western SD, in the vicinity of a front that may become nearly stationary during the afternoon. Another surface low may develop near a surface trough across western KS. Very steep midlevel lapse rates will support moderate to strong buoyancy across a broad region of the central/northern Plains into parts of the upper Midwest. Storm evolution could be rather complex later today, with multiple potential areas for diurnal development and intensification, and some potential for one or more corridors of severe/damaging gusts, along with some threat for hail and possibly a tornado or two. ...SD and vicinity... Widely scattered thunderstorm development is expected this afternoon across parts of western SD, near/north of the front and in the vicinity of the surface low. 30-40 kt of midlevel flow atop low-level easterlies north of the boundary will provide sufficient deep-layer shear for storm organization, and a couple supercells will be possible initially. Hail and isolated severe gusts will be a threat with the initial discrete development. Outflow consolidation could support development of an upscale-growing cluster (as depicted by several HREF members), which could propagate quickly east-southeastward toward southeast SD and vicinity, with a threat of severe gusts potentially exceeding 75 mph. Greater unconditional wind probabilities may eventually be needed if confidence increases regarding this scenario. ...Central High Plains... While large-scale forcing/ascent will be somewhat weaker with southward extent, strong heating and removal of MLCINH will support at least isolated storm development from western/central NE into western KS, and potentially into northeast CO. Moderate to strong buoyancy, steep lapse rates, and moderate deep-layer shear will support a conditional risk of severe storms (including supercell potential) with any diurnal development in this region. Storm coverage remains uncertain, but the environment will conditionally support potential for both severe gusts and hail. ...Eastern NE into IA/MO... A potential MCV evolving from overnight convection across western/central NE will move eastward through the day. Some guidance depicts diurnal storm development in the vicinity of this feature, somewhere from eastern NE into western IA. Should this occur, strong buoyancy and sufficient deep-layer shear could support at least an isolated severe threat, with some potential for upscale growth into a southeastward-moving cluster. Even if substantial diurnal development does not occur, an increasing low-level jet could support increasing storm coverage across parts of IA/MO later this evening into the overnight, which could be accompanied by a threat for isolated strong/damaging gusts and/or hail. ...Southwest into northeast MN... In the wake of potential elevated convection during the morning, scattered thunderstorms are expected along/ahead of the front during the afternoon across parts of MN. A notable weakness in midlevel flow will tend to limit deep-layer shear and storm organization across the region, but MLCAPE increasing above 2000 J/kg and some modest enhancement to low-level flow could support localized damaging winds, and perhaps some hail with the strongest updrafts. ...Parts of MT/WY... Relatively high-based convection is expected to develop across parts of western/central WY into southern MT, in advance of a shortwave trough moving eastward out of the Pacific Northwest. A couple stronger outflow-driven cells/clusters will be possible, with an attendant threat for isolated severe gusts. ...MS/AL/TN... Rather widespread convection is expected later today from parts of the Ohio Valley into the Southeast, in association with a mid/upper-level trough moving northeastward out of the Ozarks vicinity. Somewhat stronger heating and midlevel flow along the southern periphery of this trough could support a few strong storms across parts of MS/AL/TN, but with generally modest deep-layer shear and weak midlevel lapse rates, the potential for any organized severe threat across this region remains uncertain. ..Dean/Weinman.. 07/28/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Sun Jul 28 2024 Valid 281200Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN AND CENTRAL PLAINS... ...SUMMARY... Scattered strong to severe thunderstorms are expected across parts of the central and northern Plains this afternoon into tonight. ...Synopsis... Multiple midlevel shortwave troughs, some convectively enhanced, are forecast to move across parts of the central and northern Great Plains later today into tonight. One surface low is forecast to gradually deepen across western SD, in the vicinity of a front that may become nearly stationary during the afternoon. Another surface low may develop near a surface trough across western KS. Very steep midlevel lapse rates will support moderate to strong buoyancy across a broad region of the central/northern Plains into parts of the upper Midwest. Storm evolution could be rather complex later today, with multiple potential areas for diurnal development and intensification, and some potential for one or more corridors of severe/damaging gusts, along with some threat for hail and possibly a tornado or two. ...SD and vicinity... Widely scattered thunderstorm development is expected this afternoon across parts of western SD, near/north of the front and in the vicinity of the surface low. 30-40 kt of midlevel flow atop low-level easterlies north of the boundary will provide sufficient deep-layer shear for storm organization, and a couple supercells will be possible initially. Hail and isolated severe gusts will be a threat with the initial discrete development. Outflow consolidation could support development of an upscale-growing cluster (as depicted by several HREF members), which could propagate quickly east-southeastward toward southeast SD and vicinity, with a threat of severe gusts potentially exceeding 75 mph. Greater unconditional wind probabilities may eventually be needed if confidence increases regarding this scenario. ...Central High Plains... While large-scale forcing/ascent will be somewhat weaker with southward extent, strong heating and removal of MLCINH will support at least isolated storm development from western/central NE into western KS, and potentially into northeast CO. Moderate to strong buoyancy, steep lapse rates, and moderate deep-layer shear will support a conditional risk of severe storms (including supercell potential) with any diurnal development in this region. Storm coverage remains uncertain, but the environment will conditionally support potential for both severe gusts and hail. ...Eastern NE into IA/MO... A potential MCV evolving from overnight convection across western/central NE will move eastward through the day. Some guidance depicts diurnal storm development in the vicinity of this feature, somewhere from eastern NE into western IA. Should this occur, strong buoyancy and sufficient deep-layer shear could support at least an isolated severe threat, with some potential for upscale growth into a southeastward-moving cluster. Even if substantial diurnal development does not occur, an increasing low-level jet could support increasing storm coverage across parts of IA/MO later this evening into the overnight, which could be accompanied by a threat for isolated strong/damaging gusts and/or hail. ...Southwest into northeast MN... In the wake of potential elevated convection during the morning, scattered thunderstorms are expected along/ahead of the front during the afternoon across parts of MN. A notable weakness in midlevel flow will tend to limit deep-layer shear and storm organization across the region, but MLCAPE increasing above 2000 J/kg and some modest enhancement to low-level flow could support localized damaging winds, and perhaps some hail with the strongest updrafts. ...Parts of MT/WY... Relatively high-based convection is expected to develop across parts of western/central WY into southern MT, in advance of a shortwave trough moving eastward out of the Pacific Northwest. A couple stronger outflow-driven cells/clusters will be possible, with an attendant threat for isolated severe gusts. ...MS/AL/TN... Rather widespread convection is expected later today from parts of the Ohio Valley into the Southeast, in association with a mid/upper-level trough moving northeastward out of the Ozarks vicinity. Somewhat stronger heating and midlevel flow along the southern periphery of this trough could support a few strong storms across parts of MS/AL/TN, but with generally modest deep-layer shear and weak midlevel lapse rates, the potential for any organized severe threat across this region remains uncertain. ..Dean/Weinman.. 07/28/2024 Read more

000
ABPZ20 KNHC 280502
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM PDT Sat Jul 27 2024

For the eastern North Pacific...east of 140 degrees west longitude:

South of Southern Mexico:
A large area of cloudiness and showers located a few hundred miles
south of Guatemala and southern Mexico is associated with a
tropical wave. Environmental conditions appear conducive for
gradual development of this system, and a tropical depression could
form during the early or middle part of next week. The system is
forecast to move westward to west-northwestward at 10 to 15 mph
during the next several days, remaining offshore of the southern
coast of Mexico.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 7 days...medium...60 percent.

Western East Pacific:
An area of low pressure could form by the middle of next week well
to the southwest of the southern tip of the Baja California
Peninsula. Some slow development of this system is possible during
the middle and latter parts of the week while it moves westward to
west-northwestward across the western portion of the basin.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...30 percent.

South of Central America and Southern Mexico:
Another area of low pressure could form offshore of the coast of
Central America and southern Mexico during the latter part of next
week. Some gradual development of this system is possible thereafter
while it moves generally westward.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...20 percent.

$$
Forecaster Blake

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0759 PM CDT Sat Jul 27 2024 Valid 280100Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF CENTRAL/EASTERN ND INTO NORTHERN MN... ...SUMMARY... Strong to potentially severe storms remain possible tonight across parts of the Dakotas into northern Minnesota, the central High Plains, and central/northern Rockies. ...Parts of ND into northern MN... Storms have struggled to mature thus far today across parts of ND/MN. However, moderate to strong instability and sufficient deep-layer shear for organized convection remain in place across parts of ND into northern MN this evening, as noted on the KBIS and KINL 00Z soundings. Convective evolution through this evening remains rather uncertain, but some increase in storm coverage is expected with time later tonight from eastern ND into northwest MN, in conjunction with a strengthening low-level jet and a compact shortwave trough that will move quickly eastward across parts of southern SK/MB. The strongest storms could pose some threat of hail and isolated damaging gusts, with a somewhat greater coverage of damaging-wind threat possible if any upscale growth can evolve. ...Parts of the central/northern High Plains... Scattered strong storms are ongoing this evening from parts of SD into western NE and northeast CO, within a moderately unstable and modestly sheared environment. Isolated strong/severe gusts and hail may continue to be a threat with these storms through the evening, before increasing MLCINH results in a general weakening trend later tonight. ...Southeast ID/northeast UT into western WY... A small cluster of strong storms across parts of northeast UT/southeast ID may continue to pose a threat of isolated severe gusts as it spreads eastward into southwest WY early this evening, within a weakly unstable but favorably sheared environment. Gradual weakening is expected later this evening due to increasing CINH with time and eastward extent. ..Dean.. 07/28/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0759 PM CDT Sat Jul 27 2024 Valid 280100Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF CENTRAL/EASTERN ND INTO NORTHERN MN... ...SUMMARY... Strong to potentially severe storms remain possible tonight across parts of the Dakotas into northern Minnesota, the central High Plains, and central/northern Rockies. ...Parts of ND into northern MN... Storms have struggled to mature thus far today across parts of ND/MN. However, moderate to strong instability and sufficient deep-layer shear for organized convection remain in place across parts of ND into northern MN this evening, as noted on the KBIS and KINL 00Z soundings. Convective evolution through this evening remains rather uncertain, but some increase in storm coverage is expected with time later tonight from eastern ND into northwest MN, in conjunction with a strengthening low-level jet and a compact shortwave trough that will move quickly eastward across parts of southern SK/MB. The strongest storms could pose some threat of hail and isolated damaging gusts, with a somewhat greater coverage of damaging-wind threat possible if any upscale growth can evolve. ...Parts of the central/northern High Plains... Scattered strong storms are ongoing this evening from parts of SD into western NE and northeast CO, within a moderately unstable and modestly sheared environment. Isolated strong/severe gusts and hail may continue to be a threat with these storms through the evening, before increasing MLCINH results in a general weakening trend later tonight. ...Southeast ID/northeast UT into western WY... A small cluster of strong storms across parts of northeast UT/southeast ID may continue to pose a threat of isolated severe gusts as it spreads eastward into southwest WY early this evening, within a weakly unstable but favorably sheared environment. Gradual weakening is expected later this evening due to increasing CINH with time and eastward extent. ..Dean.. 07/28/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0759 PM CDT Sat Jul 27 2024 Valid 280100Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF CENTRAL/EASTERN ND INTO NORTHERN MN... ...SUMMARY... Strong to potentially severe storms remain possible tonight across parts of the Dakotas into northern Minnesota, the central High Plains, and central/northern Rockies. ...Parts of ND into northern MN... Storms have struggled to mature thus far today across parts of ND/MN. However, moderate to strong instability and sufficient deep-layer shear for organized convection remain in place across parts of ND into northern MN this evening, as noted on the KBIS and KINL 00Z soundings. Convective evolution through this evening remains rather uncertain, but some increase in storm coverage is expected with time later tonight from eastern ND into northwest MN, in conjunction with a strengthening low-level jet and a compact shortwave trough that will move quickly eastward across parts of southern SK/MB. The strongest storms could pose some threat of hail and isolated damaging gusts, with a somewhat greater coverage of damaging-wind threat possible if any upscale growth can evolve. ...Parts of the central/northern High Plains... Scattered strong storms are ongoing this evening from parts of SD into western NE and northeast CO, within a moderately unstable and modestly sheared environment. Isolated strong/severe gusts and hail may continue to be a threat with these storms through the evening, before increasing MLCINH results in a general weakening trend later tonight. ...Southeast ID/northeast UT into western WY... A small cluster of strong storms across parts of northeast UT/southeast ID may continue to pose a threat of isolated severe gusts as it spreads eastward into southwest WY early this evening, within a weakly unstable but favorably sheared environment. Gradual weakening is expected later this evening due to increasing CINH with time and eastward extent. ..Dean.. 07/28/2024 Read more

MD 1717 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF CENTRAL/EASTERN NORTH DAKOTA INTO FAR NORTHWESTERN MINNESOTA
Mesoscale Discussion 1717 NWS Storm Prediction Center Norman OK 0612 PM CDT Sat Jul 27 2024 Areas affected...Portions of central/eastern North Dakota into far northwestern Minnesota Concerning...Severe potential...Watch possible Valid 272312Z - 280115Z Probability of Watch Issuance...40 percent SUMMARY...The area is being monitored for thunderstorm development, with a risk of damaging winds and large hail. A watch may eventually be needed for parts of the area. DISCUSSION...As of 2300Z, the KBIS/KMBX radars show increasing surface convergence along a NNW/SSE-oriented cold front draped across central North Dakota. Boundary-layer cumulus is also expanding in coverage and deepening along the front, generally along/south of I-94. Given a warm/moist and uncapped pre-convective air mass, isolated to widely scattered thunderstorm development is expected along the front in the next hour or so. Steep midlevel lapse rates (associated with an EML) above the warm/moist boundary layer are contributing to moderate surface-based instability ahead of the front. This, combined with around 35 kt of west-southwesterly effective shear (oriented oblique to the front), will support a mix of organized clusters and semi-discrete supercells. Large hail (generally up to 1.75 inches) and locally damaging wind gusts (up to 70 mph) will be possible (especially with any initial semi-discrete supercells). With time, the damaging-wind risk may increase if storms can grow locally upscale as they track eastward. There is still some uncertainty on overall storm coverage and longevity (given fairly weak large-scale ascent and gradually increasing nocturnal static stability). Trends are being monitored for a possible watch issuance for parts of the area this evening. ..Weinman/Hart.. 07/27/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FGF...BIS... LAT...LON 48130053 48849985 49019944 49099864 49089708 48809676 48239683 47429765 46629885 46349982 46260062 46340100 46470118 46790122 47370094 48130053 Read more

000
ABPZ20 KNHC 272315
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 PM PDT Sat Jul 27 2024

For the eastern North Pacific...east of 140 degrees west longitude:

South of Southern Mexico:
A large area of shower and thunderstorm activity located a few
hundred miles south of Guatemala and southern Mexico is associated
with a tropical wave. Environmental conditions appear conducive for
gradual development of this system, and a tropical depression could
form during the early or middle part of next week. The system is
forecast to move westward to west-northwestward at 10 to 15 mph
during the next several days, remaining offshore of the southern
coast of Mexico.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 7 days...medium...60 percent.

Western East Pacific:
An area of low pressure could form by the middle of next week well
to the southwest of the southern tip of the Baja California
Peninsula. Some slow development of this system is possible during
the middle and latter parts of the week while it moves westward to
west-northwestward across the western portion of the basin.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...30 percent.

South of Central America and Southern Mexico:
Another area of low pressure could form offshore of the coast of
Central America and southern Mexico during the latter part of next
week. Some gradual development of this system is possible thereafter
while it moves generally westward.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...20 percent.

$$
Forecaster Reinhart