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SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0750 AM CDT Fri Aug 16 2024 Valid 161300Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR MUCH OF KANSAS INTO NORTHERN OKLAHOMA AND INTO NORTHWEST ARKANSAS AND FAR SOUTHWEST MISSOURI... ...SUMMARY... Scattered severe thunderstorms are possible for much of Kansas into northern Oklahoma and into northwest Arkansas. Large to very large hail and severe gusts are the expected hazards with the stronger thunderstorms. ...Central/Southern Plains Region... A surface front will become draped from the Ozarks westward into KS and arcing into the north-central High Plains by mid afternoon. With this region largely in between a mid-level anticyclone over NM and an upper low over the Upper Midwest, a subtle impulse in water-vapor imagery over the central High Plains is forecast to gradually move east across KS today. Models show an instability axis paralleling the frontal zone where the combination of deep-layer shear/buoyancy will be greatest. It is within the Slight Risk where the potential for organized storms, including supercells and eventually severe clusters/line segments appear to be most probable. However, given the relatively modest forcing, it is not entirely clear how storm clusters evolve except for the peak storm intensity/coverage to generally focus late this afternoon into the evening. This activity will likely continue to move east-southeast into richer moisture in the northeast OK vicinity and yield a risk for severe gusts potentially into tonight. Farther southwest into western OK and adjacent parts of TX, a hot and deeply mixed boundary layer will feature very steep 0-3 km lapse rates by late afternoon. Isolated to scattered storms are indicated in model guidance. Severe gusts associated with evaporatively cooled downdrafts appear to be the primary hazard before this activity weakens by mid evening. ...KY/TN Valley/Mid South... Scattered showers/thunderstorm ongoing this morning across parts of TN/KY will continue east through the morning. Heating ahead of this activity will act to destabilize a moist airmass with additional development forecast on trailing outflow. Isolated to widely scattered damaging gusts are possible with the more intense storms once the boundary layer sufficiently destabilizes. Some recent model guidance indicates a focused mesoscale corridor for wind potential may evolve across the TN Valley but uncertainty is relatively high for this scenario. ...Southern Great Lakes vicinity... Water-vapor imagery this morning shows a leading mid-level vorticity maximum moving east across northern IN/southern Lower MI. Weak instability immediately downstream of this impulse (250 J/kg MUCAPE per the Detroit 12 UTC raob) and an associated cloud shield will likely limited storm intensity until stronger heating can occur. Upstream of the aforementioned disturbance, another mid-level shortwave is forecast to rotate east-southeastward from MN towards Lake Michigan through the early evening. Heating ahead of this impulse will yield at least weak to moderate buoyancy by early afternoon. Isolated strong/severe thunderstorms are expected to develop immediately ahead of the upper low. Hail/wind are possible with storms that evolve along this corridor of stronger instability. ..Smith/Mosier.. 08/16/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0750 AM CDT Fri Aug 16 2024 Valid 161300Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR MUCH OF KANSAS INTO NORTHERN OKLAHOMA AND INTO NORTHWEST ARKANSAS AND FAR SOUTHWEST MISSOURI... ...SUMMARY... Scattered severe thunderstorms are possible for much of Kansas into northern Oklahoma and into northwest Arkansas. Large to very large hail and severe gusts are the expected hazards with the stronger thunderstorms. ...Central/Southern Plains Region... A surface front will become draped from the Ozarks westward into KS and arcing into the north-central High Plains by mid afternoon. With this region largely in between a mid-level anticyclone over NM and an upper low over the Upper Midwest, a subtle impulse in water-vapor imagery over the central High Plains is forecast to gradually move east across KS today. Models show an instability axis paralleling the frontal zone where the combination of deep-layer shear/buoyancy will be greatest. It is within the Slight Risk where the potential for organized storms, including supercells and eventually severe clusters/line segments appear to be most probable. However, given the relatively modest forcing, it is not entirely clear how storm clusters evolve except for the peak storm intensity/coverage to generally focus late this afternoon into the evening. This activity will likely continue to move east-southeast into richer moisture in the northeast OK vicinity and yield a risk for severe gusts potentially into tonight. Farther southwest into western OK and adjacent parts of TX, a hot and deeply mixed boundary layer will feature very steep 0-3 km lapse rates by late afternoon. Isolated to scattered storms are indicated in model guidance. Severe gusts associated with evaporatively cooled downdrafts appear to be the primary hazard before this activity weakens by mid evening. ...KY/TN Valley/Mid South... Scattered showers/thunderstorm ongoing this morning across parts of TN/KY will continue east through the morning. Heating ahead of this activity will act to destabilize a moist airmass with additional development forecast on trailing outflow. Isolated to widely scattered damaging gusts are possible with the more intense storms once the boundary layer sufficiently destabilizes. Some recent model guidance indicates a focused mesoscale corridor for wind potential may evolve across the TN Valley but uncertainty is relatively high for this scenario. ...Southern Great Lakes vicinity... Water-vapor imagery this morning shows a leading mid-level vorticity maximum moving east across northern IN/southern Lower MI. Weak instability immediately downstream of this impulse (250 J/kg MUCAPE per the Detroit 12 UTC raob) and an associated cloud shield will likely limited storm intensity until stronger heating can occur. Upstream of the aforementioned disturbance, another mid-level shortwave is forecast to rotate east-southeastward from MN towards Lake Michigan through the early evening. Heating ahead of this impulse will yield at least weak to moderate buoyancy by early afternoon. Isolated strong/severe thunderstorms are expected to develop immediately ahead of the upper low. Hail/wind are possible with storms that evolve along this corridor of stronger instability. ..Smith/Mosier.. 08/16/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0750 AM CDT Fri Aug 16 2024 Valid 161300Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR MUCH OF KANSAS INTO NORTHERN OKLAHOMA AND INTO NORTHWEST ARKANSAS AND FAR SOUTHWEST MISSOURI... ...SUMMARY... Scattered severe thunderstorms are possible for much of Kansas into northern Oklahoma and into northwest Arkansas. Large to very large hail and severe gusts are the expected hazards with the stronger thunderstorms. ...Central/Southern Plains Region... A surface front will become draped from the Ozarks westward into KS and arcing into the north-central High Plains by mid afternoon. With this region largely in between a mid-level anticyclone over NM and an upper low over the Upper Midwest, a subtle impulse in water-vapor imagery over the central High Plains is forecast to gradually move east across KS today. Models show an instability axis paralleling the frontal zone where the combination of deep-layer shear/buoyancy will be greatest. It is within the Slight Risk where the potential for organized storms, including supercells and eventually severe clusters/line segments appear to be most probable. However, given the relatively modest forcing, it is not entirely clear how storm clusters evolve except for the peak storm intensity/coverage to generally focus late this afternoon into the evening. This activity will likely continue to move east-southeast into richer moisture in the northeast OK vicinity and yield a risk for severe gusts potentially into tonight. Farther southwest into western OK and adjacent parts of TX, a hot and deeply mixed boundary layer will feature very steep 0-3 km lapse rates by late afternoon. Isolated to scattered storms are indicated in model guidance. Severe gusts associated with evaporatively cooled downdrafts appear to be the primary hazard before this activity weakens by mid evening. ...KY/TN Valley/Mid South... Scattered showers/thunderstorm ongoing this morning across parts of TN/KY will continue east through the morning. Heating ahead of this activity will act to destabilize a moist airmass with additional development forecast on trailing outflow. Isolated to widely scattered damaging gusts are possible with the more intense storms once the boundary layer sufficiently destabilizes. Some recent model guidance indicates a focused mesoscale corridor for wind potential may evolve across the TN Valley but uncertainty is relatively high for this scenario. ...Southern Great Lakes vicinity... Water-vapor imagery this morning shows a leading mid-level vorticity maximum moving east across northern IN/southern Lower MI. Weak instability immediately downstream of this impulse (250 J/kg MUCAPE per the Detroit 12 UTC raob) and an associated cloud shield will likely limited storm intensity until stronger heating can occur. Upstream of the aforementioned disturbance, another mid-level shortwave is forecast to rotate east-southeastward from MN towards Lake Michigan through the early evening. Heating ahead of this impulse will yield at least weak to moderate buoyancy by early afternoon. Isolated strong/severe thunderstorms are expected to develop immediately ahead of the upper low. Hail/wind are possible with storms that evolve along this corridor of stronger instability. ..Smith/Mosier.. 08/16/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0750 AM CDT Fri Aug 16 2024 Valid 161300Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR MUCH OF KANSAS INTO NORTHERN OKLAHOMA AND INTO NORTHWEST ARKANSAS AND FAR SOUTHWEST MISSOURI... ...SUMMARY... Scattered severe thunderstorms are possible for much of Kansas into northern Oklahoma and into northwest Arkansas. Large to very large hail and severe gusts are the expected hazards with the stronger thunderstorms. ...Central/Southern Plains Region... A surface front will become draped from the Ozarks westward into KS and arcing into the north-central High Plains by mid afternoon. With this region largely in between a mid-level anticyclone over NM and an upper low over the Upper Midwest, a subtle impulse in water-vapor imagery over the central High Plains is forecast to gradually move east across KS today. Models show an instability axis paralleling the frontal zone where the combination of deep-layer shear/buoyancy will be greatest. It is within the Slight Risk where the potential for organized storms, including supercells and eventually severe clusters/line segments appear to be most probable. However, given the relatively modest forcing, it is not entirely clear how storm clusters evolve except for the peak storm intensity/coverage to generally focus late this afternoon into the evening. This activity will likely continue to move east-southeast into richer moisture in the northeast OK vicinity and yield a risk for severe gusts potentially into tonight. Farther southwest into western OK and adjacent parts of TX, a hot and deeply mixed boundary layer will feature very steep 0-3 km lapse rates by late afternoon. Isolated to scattered storms are indicated in model guidance. Severe gusts associated with evaporatively cooled downdrafts appear to be the primary hazard before this activity weakens by mid evening. ...KY/TN Valley/Mid South... Scattered showers/thunderstorm ongoing this morning across parts of TN/KY will continue east through the morning. Heating ahead of this activity will act to destabilize a moist airmass with additional development forecast on trailing outflow. Isolated to widely scattered damaging gusts are possible with the more intense storms once the boundary layer sufficiently destabilizes. Some recent model guidance indicates a focused mesoscale corridor for wind potential may evolve across the TN Valley but uncertainty is relatively high for this scenario. ...Southern Great Lakes vicinity... Water-vapor imagery this morning shows a leading mid-level vorticity maximum moving east across northern IN/southern Lower MI. Weak instability immediately downstream of this impulse (250 J/kg MUCAPE per the Detroit 12 UTC raob) and an associated cloud shield will likely limited storm intensity until stronger heating can occur. Upstream of the aforementioned disturbance, another mid-level shortwave is forecast to rotate east-southeastward from MN towards Lake Michigan through the early evening. Heating ahead of this impulse will yield at least weak to moderate buoyancy by early afternoon. Isolated strong/severe thunderstorms are expected to develop immediately ahead of the upper low. Hail/wind are possible with storms that evolve along this corridor of stronger instability. ..Smith/Mosier.. 08/16/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0750 AM CDT Fri Aug 16 2024 Valid 161300Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR MUCH OF KANSAS INTO NORTHERN OKLAHOMA AND INTO NORTHWEST ARKANSAS AND FAR SOUTHWEST MISSOURI... ...SUMMARY... Scattered severe thunderstorms are possible for much of Kansas into northern Oklahoma and into northwest Arkansas. Large to very large hail and severe gusts are the expected hazards with the stronger thunderstorms. ...Central/Southern Plains Region... A surface front will become draped from the Ozarks westward into KS and arcing into the north-central High Plains by mid afternoon. With this region largely in between a mid-level anticyclone over NM and an upper low over the Upper Midwest, a subtle impulse in water-vapor imagery over the central High Plains is forecast to gradually move east across KS today. Models show an instability axis paralleling the frontal zone where the combination of deep-layer shear/buoyancy will be greatest. It is within the Slight Risk where the potential for organized storms, including supercells and eventually severe clusters/line segments appear to be most probable. However, given the relatively modest forcing, it is not entirely clear how storm clusters evolve except for the peak storm intensity/coverage to generally focus late this afternoon into the evening. This activity will likely continue to move east-southeast into richer moisture in the northeast OK vicinity and yield a risk for severe gusts potentially into tonight. Farther southwest into western OK and adjacent parts of TX, a hot and deeply mixed boundary layer will feature very steep 0-3 km lapse rates by late afternoon. Isolated to scattered storms are indicated in model guidance. Severe gusts associated with evaporatively cooled downdrafts appear to be the primary hazard before this activity weakens by mid evening. ...KY/TN Valley/Mid South... Scattered showers/thunderstorm ongoing this morning across parts of TN/KY will continue east through the morning. Heating ahead of this activity will act to destabilize a moist airmass with additional development forecast on trailing outflow. Isolated to widely scattered damaging gusts are possible with the more intense storms once the boundary layer sufficiently destabilizes. Some recent model guidance indicates a focused mesoscale corridor for wind potential may evolve across the TN Valley but uncertainty is relatively high for this scenario. ...Southern Great Lakes vicinity... Water-vapor imagery this morning shows a leading mid-level vorticity maximum moving east across northern IN/southern Lower MI. Weak instability immediately downstream of this impulse (250 J/kg MUCAPE per the Detroit 12 UTC raob) and an associated cloud shield will likely limited storm intensity until stronger heating can occur. Upstream of the aforementioned disturbance, another mid-level shortwave is forecast to rotate east-southeastward from MN towards Lake Michigan through the early evening. Heating ahead of this impulse will yield at least weak to moderate buoyancy by early afternoon. Isolated strong/severe thunderstorms are expected to develop immediately ahead of the upper low. Hail/wind are possible with storms that evolve along this corridor of stronger instability. ..Smith/Mosier.. 08/16/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0750 AM CDT Fri Aug 16 2024 Valid 161300Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR MUCH OF KANSAS INTO NORTHERN OKLAHOMA AND INTO NORTHWEST ARKANSAS AND FAR SOUTHWEST MISSOURI... ...SUMMARY... Scattered severe thunderstorms are possible for much of Kansas into northern Oklahoma and into northwest Arkansas. Large to very large hail and severe gusts are the expected hazards with the stronger thunderstorms. ...Central/Southern Plains Region... A surface front will become draped from the Ozarks westward into KS and arcing into the north-central High Plains by mid afternoon. With this region largely in between a mid-level anticyclone over NM and an upper low over the Upper Midwest, a subtle impulse in water-vapor imagery over the central High Plains is forecast to gradually move east across KS today. Models show an instability axis paralleling the frontal zone where the combination of deep-layer shear/buoyancy will be greatest. It is within the Slight Risk where the potential for organized storms, including supercells and eventually severe clusters/line segments appear to be most probable. However, given the relatively modest forcing, it is not entirely clear how storm clusters evolve except for the peak storm intensity/coverage to generally focus late this afternoon into the evening. This activity will likely continue to move east-southeast into richer moisture in the northeast OK vicinity and yield a risk for severe gusts potentially into tonight. Farther southwest into western OK and adjacent parts of TX, a hot and deeply mixed boundary layer will feature very steep 0-3 km lapse rates by late afternoon. Isolated to scattered storms are indicated in model guidance. Severe gusts associated with evaporatively cooled downdrafts appear to be the primary hazard before this activity weakens by mid evening. ...KY/TN Valley/Mid South... Scattered showers/thunderstorm ongoing this morning across parts of TN/KY will continue east through the morning. Heating ahead of this activity will act to destabilize a moist airmass with additional development forecast on trailing outflow. Isolated to widely scattered damaging gusts are possible with the more intense storms once the boundary layer sufficiently destabilizes. Some recent model guidance indicates a focused mesoscale corridor for wind potential may evolve across the TN Valley but uncertainty is relatively high for this scenario. ...Southern Great Lakes vicinity... Water-vapor imagery this morning shows a leading mid-level vorticity maximum moving east across northern IN/southern Lower MI. Weak instability immediately downstream of this impulse (250 J/kg MUCAPE per the Detroit 12 UTC raob) and an associated cloud shield will likely limited storm intensity until stronger heating can occur. Upstream of the aforementioned disturbance, another mid-level shortwave is forecast to rotate east-southeastward from MN towards Lake Michigan through the early evening. Heating ahead of this impulse will yield at least weak to moderate buoyancy by early afternoon. Isolated strong/severe thunderstorms are expected to develop immediately ahead of the upper low. Hail/wind are possible with storms that evolve along this corridor of stronger instability. ..Smith/Mosier.. 08/16/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0750 AM CDT Fri Aug 16 2024 Valid 161300Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR MUCH OF KANSAS INTO NORTHERN OKLAHOMA AND INTO NORTHWEST ARKANSAS AND FAR SOUTHWEST MISSOURI... ...SUMMARY... Scattered severe thunderstorms are possible for much of Kansas into northern Oklahoma and into northwest Arkansas. Large to very large hail and severe gusts are the expected hazards with the stronger thunderstorms. ...Central/Southern Plains Region... A surface front will become draped from the Ozarks westward into KS and arcing into the north-central High Plains by mid afternoon. With this region largely in between a mid-level anticyclone over NM and an upper low over the Upper Midwest, a subtle impulse in water-vapor imagery over the central High Plains is forecast to gradually move east across KS today. Models show an instability axis paralleling the frontal zone where the combination of deep-layer shear/buoyancy will be greatest. It is within the Slight Risk where the potential for organized storms, including supercells and eventually severe clusters/line segments appear to be most probable. However, given the relatively modest forcing, it is not entirely clear how storm clusters evolve except for the peak storm intensity/coverage to generally focus late this afternoon into the evening. This activity will likely continue to move east-southeast into richer moisture in the northeast OK vicinity and yield a risk for severe gusts potentially into tonight. Farther southwest into western OK and adjacent parts of TX, a hot and deeply mixed boundary layer will feature very steep 0-3 km lapse rates by late afternoon. Isolated to scattered storms are indicated in model guidance. Severe gusts associated with evaporatively cooled downdrafts appear to be the primary hazard before this activity weakens by mid evening. ...KY/TN Valley/Mid South... Scattered showers/thunderstorm ongoing this morning across parts of TN/KY will continue east through the morning. Heating ahead of this activity will act to destabilize a moist airmass with additional development forecast on trailing outflow. Isolated to widely scattered damaging gusts are possible with the more intense storms once the boundary layer sufficiently destabilizes. Some recent model guidance indicates a focused mesoscale corridor for wind potential may evolve across the TN Valley but uncertainty is relatively high for this scenario. ...Southern Great Lakes vicinity... Water-vapor imagery this morning shows a leading mid-level vorticity maximum moving east across northern IN/southern Lower MI. Weak instability immediately downstream of this impulse (250 J/kg MUCAPE per the Detroit 12 UTC raob) and an associated cloud shield will likely limited storm intensity until stronger heating can occur. Upstream of the aforementioned disturbance, another mid-level shortwave is forecast to rotate east-southeastward from MN towards Lake Michigan through the early evening. Heating ahead of this impulse will yield at least weak to moderate buoyancy by early afternoon. Isolated strong/severe thunderstorms are expected to develop immediately ahead of the upper low. Hail/wind are possible with storms that evolve along this corridor of stronger instability. ..Smith/Mosier.. 08/16/2024 Read more

000
ABPZ20 KNHC 161143
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 AM PDT Fri Aug 16 2024

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

Offshore of Southwestern Mexico:
A large area of disorganized showers and thunderstorms located a
few hundred miles south of the southwestern coast of Mexico are
associated with a tropical wave. Environmental conditions appear
conducive for gradual development of this system during the next few
days, and a tropical depression is likely to form early next week
while it moves west-northwestward away from the coast of Mexico.
* Formation chance through 48 hours...low...30 percent.
* Formation chance through 7 days...high...80 percent.

Western Portion of the East Pacific:
A broad area of low pressure could form by this weekend well to the
west-southwest of the southern tip of the Baja California peninsula.
Some slow development of this system is possible during the early
and middle parts of next week while it moves generally westward
across the western portion of the East Pacific and into the Central
Pacific basin. Information on this system's development can also
be found in the Tropical Weather Outlook for the Central Pacific
basin.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...medium...40 percent.

&&
The Tropical Weather Outlook for the Central Pacific basin can be
found under AWIPS header HFOTWOCP and WMO header ACPN50 PHFO and on
the web at hurricanes.gov

$$
Forecaster Berg

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0344 AM CDT Fri Aug 16 2024 Valid 191200Z - 241200Z ...DISCUSSION... ...Monday/Day 4 to Wednesday/Day 6... An upper-level ridge is forecast to remain over the High Plains from early to mid week, as an upper-level trough moves slowly eastward across the eastern U.S. Surface high pressure, associated with the trough is forecast to move from the middle to upper Mississippi Valley on Monday to the middle and upper Atlantic Seaboard by Wednesday. Due to this high, the airmass across much of the eastern third of the U.S. will likely become drier and less unstable from Monday to Wednesday, making conditions less favorable for severe storms. Further to the west, a south-to-north corridor of moderate instability is forecast to develop each day, remaining in a similar position across the central and northern Plains. Thunderstorms will be possible each afternoon and evening to the east of the ridge near the axis of instability. It appears that deep-layer shear will be relatively weak near instability axis, which will favor less storm organization. Still, a marginal severe threat will be possible due to the strong instability. ...Thursday/Day 7 and Friday/Day 8... The upper-level ridge in the north-central U.S. is forecast to move eastward from the northern Plains on Thursday into the western Great Lakes region by Friday. An axis of moderate to strong instability is forecast to remain over the central and northern Plains. Thunderstorms that form each afternoon close the instability axis will have a chance be severe. Although there is a lot of uncertainty this far out in the forecast cycle, the subsidence and weaker deep-layer shear associated with the upper-level ridge, should negatively impact severe potential. However, instability could be strong enough for a marginal severe threat, mainly during the afternoon and evening on Thursday and Friday. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0344 AM CDT Fri Aug 16 2024 Valid 191200Z - 241200Z ...DISCUSSION... ...Monday/Day 4 to Wednesday/Day 6... An upper-level ridge is forecast to remain over the High Plains from early to mid week, as an upper-level trough moves slowly eastward across the eastern U.S. Surface high pressure, associated with the trough is forecast to move from the middle to upper Mississippi Valley on Monday to the middle and upper Atlantic Seaboard by Wednesday. Due to this high, the airmass across much of the eastern third of the U.S. will likely become drier and less unstable from Monday to Wednesday, making conditions less favorable for severe storms. Further to the west, a south-to-north corridor of moderate instability is forecast to develop each day, remaining in a similar position across the central and northern Plains. Thunderstorms will be possible each afternoon and evening to the east of the ridge near the axis of instability. It appears that deep-layer shear will be relatively weak near instability axis, which will favor less storm organization. Still, a marginal severe threat will be possible due to the strong instability. ...Thursday/Day 7 and Friday/Day 8... The upper-level ridge in the north-central U.S. is forecast to move eastward from the northern Plains on Thursday into the western Great Lakes region by Friday. An axis of moderate to strong instability is forecast to remain over the central and northern Plains. Thunderstorms that form each afternoon close the instability axis will have a chance be severe. Although there is a lot of uncertainty this far out in the forecast cycle, the subsidence and weaker deep-layer shear associated with the upper-level ridge, should negatively impact severe potential. However, instability could be strong enough for a marginal severe threat, mainly during the afternoon and evening on Thursday and Friday. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0344 AM CDT Fri Aug 16 2024 Valid 191200Z - 241200Z ...DISCUSSION... ...Monday/Day 4 to Wednesday/Day 6... An upper-level ridge is forecast to remain over the High Plains from early to mid week, as an upper-level trough moves slowly eastward across the eastern U.S. Surface high pressure, associated with the trough is forecast to move from the middle to upper Mississippi Valley on Monday to the middle and upper Atlantic Seaboard by Wednesday. Due to this high, the airmass across much of the eastern third of the U.S. will likely become drier and less unstable from Monday to Wednesday, making conditions less favorable for severe storms. Further to the west, a south-to-north corridor of moderate instability is forecast to develop each day, remaining in a similar position across the central and northern Plains. Thunderstorms will be possible each afternoon and evening to the east of the ridge near the axis of instability. It appears that deep-layer shear will be relatively weak near instability axis, which will favor less storm organization. Still, a marginal severe threat will be possible due to the strong instability. ...Thursday/Day 7 and Friday/Day 8... The upper-level ridge in the north-central U.S. is forecast to move eastward from the northern Plains on Thursday into the western Great Lakes region by Friday. An axis of moderate to strong instability is forecast to remain over the central and northern Plains. Thunderstorms that form each afternoon close the instability axis will have a chance be severe. Although there is a lot of uncertainty this far out in the forecast cycle, the subsidence and weaker deep-layer shear associated with the upper-level ridge, should negatively impact severe potential. However, instability could be strong enough for a marginal severe threat, mainly during the afternoon and evening on Thursday and Friday. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0344 AM CDT Fri Aug 16 2024 Valid 191200Z - 241200Z ...DISCUSSION... ...Monday/Day 4 to Wednesday/Day 6... An upper-level ridge is forecast to remain over the High Plains from early to mid week, as an upper-level trough moves slowly eastward across the eastern U.S. Surface high pressure, associated with the trough is forecast to move from the middle to upper Mississippi Valley on Monday to the middle and upper Atlantic Seaboard by Wednesday. Due to this high, the airmass across much of the eastern third of the U.S. will likely become drier and less unstable from Monday to Wednesday, making conditions less favorable for severe storms. Further to the west, a south-to-north corridor of moderate instability is forecast to develop each day, remaining in a similar position across the central and northern Plains. Thunderstorms will be possible each afternoon and evening to the east of the ridge near the axis of instability. It appears that deep-layer shear will be relatively weak near instability axis, which will favor less storm organization. Still, a marginal severe threat will be possible due to the strong instability. ...Thursday/Day 7 and Friday/Day 8... The upper-level ridge in the north-central U.S. is forecast to move eastward from the northern Plains on Thursday into the western Great Lakes region by Friday. An axis of moderate to strong instability is forecast to remain over the central and northern Plains. Thunderstorms that form each afternoon close the instability axis will have a chance be severe. Although there is a lot of uncertainty this far out in the forecast cycle, the subsidence and weaker deep-layer shear associated with the upper-level ridge, should negatively impact severe potential. However, instability could be strong enough for a marginal severe threat, mainly during the afternoon and evening on Thursday and Friday. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0344 AM CDT Fri Aug 16 2024 Valid 191200Z - 241200Z ...DISCUSSION... ...Monday/Day 4 to Wednesday/Day 6... An upper-level ridge is forecast to remain over the High Plains from early to mid week, as an upper-level trough moves slowly eastward across the eastern U.S. Surface high pressure, associated with the trough is forecast to move from the middle to upper Mississippi Valley on Monday to the middle and upper Atlantic Seaboard by Wednesday. Due to this high, the airmass across much of the eastern third of the U.S. will likely become drier and less unstable from Monday to Wednesday, making conditions less favorable for severe storms. Further to the west, a south-to-north corridor of moderate instability is forecast to develop each day, remaining in a similar position across the central and northern Plains. Thunderstorms will be possible each afternoon and evening to the east of the ridge near the axis of instability. It appears that deep-layer shear will be relatively weak near instability axis, which will favor less storm organization. Still, a marginal severe threat will be possible due to the strong instability. ...Thursday/Day 7 and Friday/Day 8... The upper-level ridge in the north-central U.S. is forecast to move eastward from the northern Plains on Thursday into the western Great Lakes region by Friday. An axis of moderate to strong instability is forecast to remain over the central and northern Plains. Thunderstorms that form each afternoon close the instability axis will have a chance be severe. Although there is a lot of uncertainty this far out in the forecast cycle, the subsidence and weaker deep-layer shear associated with the upper-level ridge, should negatively impact severe potential. However, instability could be strong enough for a marginal severe threat, mainly during the afternoon and evening on Thursday and Friday. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0344 AM CDT Fri Aug 16 2024 Valid 191200Z - 241200Z ...DISCUSSION... ...Monday/Day 4 to Wednesday/Day 6... An upper-level ridge is forecast to remain over the High Plains from early to mid week, as an upper-level trough moves slowly eastward across the eastern U.S. Surface high pressure, associated with the trough is forecast to move from the middle to upper Mississippi Valley on Monday to the middle and upper Atlantic Seaboard by Wednesday. Due to this high, the airmass across much of the eastern third of the U.S. will likely become drier and less unstable from Monday to Wednesday, making conditions less favorable for severe storms. Further to the west, a south-to-north corridor of moderate instability is forecast to develop each day, remaining in a similar position across the central and northern Plains. Thunderstorms will be possible each afternoon and evening to the east of the ridge near the axis of instability. It appears that deep-layer shear will be relatively weak near instability axis, which will favor less storm organization. Still, a marginal severe threat will be possible due to the strong instability. ...Thursday/Day 7 and Friday/Day 8... The upper-level ridge in the north-central U.S. is forecast to move eastward from the northern Plains on Thursday into the western Great Lakes region by Friday. An axis of moderate to strong instability is forecast to remain over the central and northern Plains. Thunderstorms that form each afternoon close the instability axis will have a chance be severe. Although there is a lot of uncertainty this far out in the forecast cycle, the subsidence and weaker deep-layer shear associated with the upper-level ridge, should negatively impact severe potential. However, instability could be strong enough for a marginal severe threat, mainly during the afternoon and evening on Thursday and Friday. Read more

MD 1918 CONCERNING SEVERE THUNDERSTORM WATCH 626... FOR CENTRAL IL...FAR NORTHWEST IN...EXTREME NORTHEAST MO
Mesoscale Discussion 1918 NWS Storm Prediction Center Norman OK 0119 AM CDT Fri Aug 16 2024 Areas affected...Central IL...Far Northwest IN...Extreme Northeast MO Concerning...Severe Thunderstorm Watch 626... Valid 160619Z - 160815Z The severe weather threat for Severe Thunderstorm Watch 626 continues. SUMMARY...The threat for damaging wind gusts continues from far northeast Missouri across central Illinois into far northwest Indiana. DISCUSSION...Thunderstorm coverage within the convective cluster ongoing across central IL has expanded southwestward along the outflow into more of west-central IL and far northeast MO over the past hour. The airmass downstream of this new development is moist and buoyant, as evidenced by the more discrete storms currently developing ahead of the line over central IL. As such, the general expectation is for this newer development to persist, and perhaps even strengthen, as it continues eastward over the next few hours. Primary risk would be damaging gusts with any bowing line segments. Farther north, the portion of the line moving across northeast IL continues to move eastward at about 40 kt. Buoyancy decreases notably from northeast IL into northern IN, and the general expectation is for this portion of the line to gradually weaken. Even so, localized damaging gusts will remain possible, particularly over the next hour or so. ..Mosier.. 08/16/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...IND...LOT...ILX...LSX...DVN... LAT...LON 40419131 41488875 41498746 40998712 40298713 39378813 39159039 39589214 40419131 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0213 AM CDT Fri Aug 16 2024 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE MID-ATLANTIC AND CAROLINAS WEST-SOUTHWESTWARD INTO THE SOUTHEAST...AND ACROSS PARTS OF THE CENTRAL AND NORTHERN HIGH PLAINS... ...SUMMARY... A marginal severe threat is expected on Sunday from the Mid-Atlantic and Carolinas west-southwestward into much of the Southeast. A marginal severe threat will also be possible across parts of the central and northern High Plains. ...Mid-Atlantic/Carolinas/Southeast... An upper-level trough is forecast to move eastward into the southern and central Appalachians on Sunday. At the surface, an associated cold front is forecast to advance eastward into the Atlantic Coastal Plains, and southeastward into the southeastern states. Ahead of the front, surface dewpoints are expected to be in the 70s F, which will contribute to moderate instability across a broad area by afternoon. Isolated to scattered thunderstorms are expected to form near the boundary. Some convection may also develop southeastward into the moist airmass. Although the upper-level trough will likely provide some support for convective development, the area ahead of the trough from the Mid-Atlantic southeastward into the eastern Gulf Coast states is forecast to have marginal deep-layer shear for severe storms. A few isolated severe gusts will be possible near and after peak heating, mainly as low-level lapse rates become steep in the late afternoon. Further west into the lower Mississippi Valley, moderate instability is expected to develop by afternoon. Mid-level flow behind the trough will be northwesterly. This will result in stronger deep-layer shear, which should be sufficient for an isolated severe threat. The main uncertainty on Sunday in the lower Mississippi Valley is how instability will be distributed by afternoon. Some model solutions suggest that a cluster of storms will develop early in the day, which could negatively impact instability across parts of the region. Areas that can avoid this negative impact could have potential for severe wind gusts and hail during the afternoon. ...Central and Northern High Plains. An upper-level ridge is forecast to remain over the High Plains on Sunday. Beneath the ridge, a somewhat moist airmass should be in place with surface dewpoints mostly in the 50s and 60s F. As surface temperature warm on Sunday, isolated thunderstorm development will be possible across much of the central High Plains. Forecast soundings Sunday afternoon from eastern Colorado northward into western South Dakota have steep low-level lapse rates and moderate deep-layer shear. This suggest an isolated severe threat will be possible. However, subsidence associated with the ridge will negatively impact convective development, and any severe threat should remain marginal. ..Broyles.. 08/16/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0213 AM CDT Fri Aug 16 2024 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE MID-ATLANTIC AND CAROLINAS WEST-SOUTHWESTWARD INTO THE SOUTHEAST...AND ACROSS PARTS OF THE CENTRAL AND NORTHERN HIGH PLAINS... ...SUMMARY... A marginal severe threat is expected on Sunday from the Mid-Atlantic and Carolinas west-southwestward into much of the Southeast. A marginal severe threat will also be possible across parts of the central and northern High Plains. ...Mid-Atlantic/Carolinas/Southeast... An upper-level trough is forecast to move eastward into the southern and central Appalachians on Sunday. At the surface, an associated cold front is forecast to advance eastward into the Atlantic Coastal Plains, and southeastward into the southeastern states. Ahead of the front, surface dewpoints are expected to be in the 70s F, which will contribute to moderate instability across a broad area by afternoon. Isolated to scattered thunderstorms are expected to form near the boundary. Some convection may also develop southeastward into the moist airmass. Although the upper-level trough will likely provide some support for convective development, the area ahead of the trough from the Mid-Atlantic southeastward into the eastern Gulf Coast states is forecast to have marginal deep-layer shear for severe storms. A few isolated severe gusts will be possible near and after peak heating, mainly as low-level lapse rates become steep in the late afternoon. Further west into the lower Mississippi Valley, moderate instability is expected to develop by afternoon. Mid-level flow behind the trough will be northwesterly. This will result in stronger deep-layer shear, which should be sufficient for an isolated severe threat. The main uncertainty on Sunday in the lower Mississippi Valley is how instability will be distributed by afternoon. Some model solutions suggest that a cluster of storms will develop early in the day, which could negatively impact instability across parts of the region. Areas that can avoid this negative impact could have potential for severe wind gusts and hail during the afternoon. ...Central and Northern High Plains. An upper-level ridge is forecast to remain over the High Plains on Sunday. Beneath the ridge, a somewhat moist airmass should be in place with surface dewpoints mostly in the 50s and 60s F. As surface temperature warm on Sunday, isolated thunderstorm development will be possible across much of the central High Plains. Forecast soundings Sunday afternoon from eastern Colorado northward into western South Dakota have steep low-level lapse rates and moderate deep-layer shear. This suggest an isolated severe threat will be possible. However, subsidence associated with the ridge will negatively impact convective development, and any severe threat should remain marginal. ..Broyles.. 08/16/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0213 AM CDT Fri Aug 16 2024 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE MID-ATLANTIC AND CAROLINAS WEST-SOUTHWESTWARD INTO THE SOUTHEAST...AND ACROSS PARTS OF THE CENTRAL AND NORTHERN HIGH PLAINS... ...SUMMARY... A marginal severe threat is expected on Sunday from the Mid-Atlantic and Carolinas west-southwestward into much of the Southeast. A marginal severe threat will also be possible across parts of the central and northern High Plains. ...Mid-Atlantic/Carolinas/Southeast... An upper-level trough is forecast to move eastward into the southern and central Appalachians on Sunday. At the surface, an associated cold front is forecast to advance eastward into the Atlantic Coastal Plains, and southeastward into the southeastern states. Ahead of the front, surface dewpoints are expected to be in the 70s F, which will contribute to moderate instability across a broad area by afternoon. Isolated to scattered thunderstorms are expected to form near the boundary. Some convection may also develop southeastward into the moist airmass. Although the upper-level trough will likely provide some support for convective development, the area ahead of the trough from the Mid-Atlantic southeastward into the eastern Gulf Coast states is forecast to have marginal deep-layer shear for severe storms. A few isolated severe gusts will be possible near and after peak heating, mainly as low-level lapse rates become steep in the late afternoon. Further west into the lower Mississippi Valley, moderate instability is expected to develop by afternoon. Mid-level flow behind the trough will be northwesterly. This will result in stronger deep-layer shear, which should be sufficient for an isolated severe threat. The main uncertainty on Sunday in the lower Mississippi Valley is how instability will be distributed by afternoon. Some model solutions suggest that a cluster of storms will develop early in the day, which could negatively impact instability across parts of the region. Areas that can avoid this negative impact could have potential for severe wind gusts and hail during the afternoon. ...Central and Northern High Plains. An upper-level ridge is forecast to remain over the High Plains on Sunday. Beneath the ridge, a somewhat moist airmass should be in place with surface dewpoints mostly in the 50s and 60s F. As surface temperature warm on Sunday, isolated thunderstorm development will be possible across much of the central High Plains. Forecast soundings Sunday afternoon from eastern Colorado northward into western South Dakota have steep low-level lapse rates and moderate deep-layer shear. This suggest an isolated severe threat will be possible. However, subsidence associated with the ridge will negatively impact convective development, and any severe threat should remain marginal. ..Broyles.. 08/16/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0213 AM CDT Fri Aug 16 2024 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE MID-ATLANTIC AND CAROLINAS WEST-SOUTHWESTWARD INTO THE SOUTHEAST...AND ACROSS PARTS OF THE CENTRAL AND NORTHERN HIGH PLAINS... ...SUMMARY... A marginal severe threat is expected on Sunday from the Mid-Atlantic and Carolinas west-southwestward into much of the Southeast. A marginal severe threat will also be possible across parts of the central and northern High Plains. ...Mid-Atlantic/Carolinas/Southeast... An upper-level trough is forecast to move eastward into the southern and central Appalachians on Sunday. At the surface, an associated cold front is forecast to advance eastward into the Atlantic Coastal Plains, and southeastward into the southeastern states. Ahead of the front, surface dewpoints are expected to be in the 70s F, which will contribute to moderate instability across a broad area by afternoon. Isolated to scattered thunderstorms are expected to form near the boundary. Some convection may also develop southeastward into the moist airmass. Although the upper-level trough will likely provide some support for convective development, the area ahead of the trough from the Mid-Atlantic southeastward into the eastern Gulf Coast states is forecast to have marginal deep-layer shear for severe storms. A few isolated severe gusts will be possible near and after peak heating, mainly as low-level lapse rates become steep in the late afternoon. Further west into the lower Mississippi Valley, moderate instability is expected to develop by afternoon. Mid-level flow behind the trough will be northwesterly. This will result in stronger deep-layer shear, which should be sufficient for an isolated severe threat. The main uncertainty on Sunday in the lower Mississippi Valley is how instability will be distributed by afternoon. Some model solutions suggest that a cluster of storms will develop early in the day, which could negatively impact instability across parts of the region. Areas that can avoid this negative impact could have potential for severe wind gusts and hail during the afternoon. ...Central and Northern High Plains. An upper-level ridge is forecast to remain over the High Plains on Sunday. Beneath the ridge, a somewhat moist airmass should be in place with surface dewpoints mostly in the 50s and 60s F. As surface temperature warm on Sunday, isolated thunderstorm development will be possible across much of the central High Plains. Forecast soundings Sunday afternoon from eastern Colorado northward into western South Dakota have steep low-level lapse rates and moderate deep-layer shear. This suggest an isolated severe threat will be possible. However, subsidence associated with the ridge will negatively impact convective development, and any severe threat should remain marginal. ..Broyles.. 08/16/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0213 AM CDT Fri Aug 16 2024 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE MID-ATLANTIC AND CAROLINAS WEST-SOUTHWESTWARD INTO THE SOUTHEAST...AND ACROSS PARTS OF THE CENTRAL AND NORTHERN HIGH PLAINS... ...SUMMARY... A marginal severe threat is expected on Sunday from the Mid-Atlantic and Carolinas west-southwestward into much of the Southeast. A marginal severe threat will also be possible across parts of the central and northern High Plains. ...Mid-Atlantic/Carolinas/Southeast... An upper-level trough is forecast to move eastward into the southern and central Appalachians on Sunday. At the surface, an associated cold front is forecast to advance eastward into the Atlantic Coastal Plains, and southeastward into the southeastern states. Ahead of the front, surface dewpoints are expected to be in the 70s F, which will contribute to moderate instability across a broad area by afternoon. Isolated to scattered thunderstorms are expected to form near the boundary. Some convection may also develop southeastward into the moist airmass. Although the upper-level trough will likely provide some support for convective development, the area ahead of the trough from the Mid-Atlantic southeastward into the eastern Gulf Coast states is forecast to have marginal deep-layer shear for severe storms. A few isolated severe gusts will be possible near and after peak heating, mainly as low-level lapse rates become steep in the late afternoon. Further west into the lower Mississippi Valley, moderate instability is expected to develop by afternoon. Mid-level flow behind the trough will be northwesterly. This will result in stronger deep-layer shear, which should be sufficient for an isolated severe threat. The main uncertainty on Sunday in the lower Mississippi Valley is how instability will be distributed by afternoon. Some model solutions suggest that a cluster of storms will develop early in the day, which could negatively impact instability across parts of the region. Areas that can avoid this negative impact could have potential for severe wind gusts and hail during the afternoon. ...Central and Northern High Plains. An upper-level ridge is forecast to remain over the High Plains on Sunday. Beneath the ridge, a somewhat moist airmass should be in place with surface dewpoints mostly in the 50s and 60s F. As surface temperature warm on Sunday, isolated thunderstorm development will be possible across much of the central High Plains. Forecast soundings Sunday afternoon from eastern Colorado northward into western South Dakota have steep low-level lapse rates and moderate deep-layer shear. This suggest an isolated severe threat will be possible. However, subsidence associated with the ridge will negatively impact convective development, and any severe threat should remain marginal. ..Broyles.. 08/16/2024 Read more