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SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1213 AM CDT Tue Sep 24 2024 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorm potential is low on Wednesday. ...Synopsis... An upper low within the base of the larger-scale upper trough extending from the Great Lakes to the Lower MS Valley will become cut-off from northern stream flow on Wednesday. As this occurs, the northern shortwave trough will progress east across the Great Lakes and southern Ontario. The developing upper cyclone over the Mid-South/Lower MS Valley will not move much through the period. However, moderately enhanced southerly deep-layer flow on the eastern flank of the cut-off low will persist over the Southeast. Meanwhile, latest forecast guidance and NHC forecasts show a strengthening tropical cyclone emerging across the eastern Gulf of Mexico. This system is forecast to remain well offshore from the southwest FL coast through 12z Thursday. ...Southeast... A stalled surface boundary/inverted trough will extend from near coastal MS/AL northeast across the central Appalachians. Near and east of this boundary, south/southeasterly low-level flow will maintain a very moist airmass with dewpoints from the mid 60s to low 70s F. Potentially widespread convection may be ongoing Wednesday morning across portions of this area, limiting destabilization. Despite vertical shear that may otherwise support organized convection, weak instability and poor lapse rates will limit severe potential, though the strongest cells may produce locally gusty winds. Further south across the FL Peninsula, southeasterly low to midlevel flow will increase, especially after 00z, as the developing tropical cyclone emerges into the eastern Gulf. Forecast soundings show enlarged, favorably curved low-level hodographs developing late in the period. However, instability across the Peninsula is expected to remain weak through early Thursday morning. At this time, tropical cyclone related tornado potential appears limited through 12z Thursday. ...Upper OH Valley/Lower Great Lakes vicinity... A cold front will move east/southeast across the Lower Great Lakes during the afternoon and into the overnight hours. Ahead of this feature, a corridor of 60s F dewpoints will be in place. However, surface heating is expected to be muted by cloud cover and showers. As a result, instability will be weak and lapse rates will remain poor, precluding severe thunderstorm potential. ..Leitman.. 09/24/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1213 AM CDT Tue Sep 24 2024 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorm potential is low on Wednesday. ...Synopsis... An upper low within the base of the larger-scale upper trough extending from the Great Lakes to the Lower MS Valley will become cut-off from northern stream flow on Wednesday. As this occurs, the northern shortwave trough will progress east across the Great Lakes and southern Ontario. The developing upper cyclone over the Mid-South/Lower MS Valley will not move much through the period. However, moderately enhanced southerly deep-layer flow on the eastern flank of the cut-off low will persist over the Southeast. Meanwhile, latest forecast guidance and NHC forecasts show a strengthening tropical cyclone emerging across the eastern Gulf of Mexico. This system is forecast to remain well offshore from the southwest FL coast through 12z Thursday. ...Southeast... A stalled surface boundary/inverted trough will extend from near coastal MS/AL northeast across the central Appalachians. Near and east of this boundary, south/southeasterly low-level flow will maintain a very moist airmass with dewpoints from the mid 60s to low 70s F. Potentially widespread convection may be ongoing Wednesday morning across portions of this area, limiting destabilization. Despite vertical shear that may otherwise support organized convection, weak instability and poor lapse rates will limit severe potential, though the strongest cells may produce locally gusty winds. Further south across the FL Peninsula, southeasterly low to midlevel flow will increase, especially after 00z, as the developing tropical cyclone emerges into the eastern Gulf. Forecast soundings show enlarged, favorably curved low-level hodographs developing late in the period. However, instability across the Peninsula is expected to remain weak through early Thursday morning. At this time, tropical cyclone related tornado potential appears limited through 12z Thursday. ...Upper OH Valley/Lower Great Lakes vicinity... A cold front will move east/southeast across the Lower Great Lakes during the afternoon and into the overnight hours. Ahead of this feature, a corridor of 60s F dewpoints will be in place. However, surface heating is expected to be muted by cloud cover and showers. As a result, instability will be weak and lapse rates will remain poor, precluding severe thunderstorm potential. ..Leitman.. 09/24/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1213 AM CDT Tue Sep 24 2024 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorm potential is low on Wednesday. ...Synopsis... An upper low within the base of the larger-scale upper trough extending from the Great Lakes to the Lower MS Valley will become cut-off from northern stream flow on Wednesday. As this occurs, the northern shortwave trough will progress east across the Great Lakes and southern Ontario. The developing upper cyclone over the Mid-South/Lower MS Valley will not move much through the period. However, moderately enhanced southerly deep-layer flow on the eastern flank of the cut-off low will persist over the Southeast. Meanwhile, latest forecast guidance and NHC forecasts show a strengthening tropical cyclone emerging across the eastern Gulf of Mexico. This system is forecast to remain well offshore from the southwest FL coast through 12z Thursday. ...Southeast... A stalled surface boundary/inverted trough will extend from near coastal MS/AL northeast across the central Appalachians. Near and east of this boundary, south/southeasterly low-level flow will maintain a very moist airmass with dewpoints from the mid 60s to low 70s F. Potentially widespread convection may be ongoing Wednesday morning across portions of this area, limiting destabilization. Despite vertical shear that may otherwise support organized convection, weak instability and poor lapse rates will limit severe potential, though the strongest cells may produce locally gusty winds. Further south across the FL Peninsula, southeasterly low to midlevel flow will increase, especially after 00z, as the developing tropical cyclone emerges into the eastern Gulf. Forecast soundings show enlarged, favorably curved low-level hodographs developing late in the period. However, instability across the Peninsula is expected to remain weak through early Thursday morning. At this time, tropical cyclone related tornado potential appears limited through 12z Thursday. ...Upper OH Valley/Lower Great Lakes vicinity... A cold front will move east/southeast across the Lower Great Lakes during the afternoon and into the overnight hours. Ahead of this feature, a corridor of 60s F dewpoints will be in place. However, surface heating is expected to be muted by cloud cover and showers. As a result, instability will be weak and lapse rates will remain poor, precluding severe thunderstorm potential. ..Leitman.. 09/24/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1213 AM CDT Tue Sep 24 2024 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorm potential is low on Wednesday. ...Synopsis... An upper low within the base of the larger-scale upper trough extending from the Great Lakes to the Lower MS Valley will become cut-off from northern stream flow on Wednesday. As this occurs, the northern shortwave trough will progress east across the Great Lakes and southern Ontario. The developing upper cyclone over the Mid-South/Lower MS Valley will not move much through the period. However, moderately enhanced southerly deep-layer flow on the eastern flank of the cut-off low will persist over the Southeast. Meanwhile, latest forecast guidance and NHC forecasts show a strengthening tropical cyclone emerging across the eastern Gulf of Mexico. This system is forecast to remain well offshore from the southwest FL coast through 12z Thursday. ...Southeast... A stalled surface boundary/inverted trough will extend from near coastal MS/AL northeast across the central Appalachians. Near and east of this boundary, south/southeasterly low-level flow will maintain a very moist airmass with dewpoints from the mid 60s to low 70s F. Potentially widespread convection may be ongoing Wednesday morning across portions of this area, limiting destabilization. Despite vertical shear that may otherwise support organized convection, weak instability and poor lapse rates will limit severe potential, though the strongest cells may produce locally gusty winds. Further south across the FL Peninsula, southeasterly low to midlevel flow will increase, especially after 00z, as the developing tropical cyclone emerges into the eastern Gulf. Forecast soundings show enlarged, favorably curved low-level hodographs developing late in the period. However, instability across the Peninsula is expected to remain weak through early Thursday morning. At this time, tropical cyclone related tornado potential appears limited through 12z Thursday. ...Upper OH Valley/Lower Great Lakes vicinity... A cold front will move east/southeast across the Lower Great Lakes during the afternoon and into the overnight hours. Ahead of this feature, a corridor of 60s F dewpoints will be in place. However, surface heating is expected to be muted by cloud cover and showers. As a result, instability will be weak and lapse rates will remain poor, precluding severe thunderstorm potential. ..Leitman.. 09/24/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1232 AM CDT Tue Sep 24 2024 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE TENNESSEE AND OHIO VALLEYS INTO THE SOUTHERN APPALACHIANS. A FEW STRONG/SEVERE STORMS ARE ALSO POSSIBLE OVER THE SOUTHERN PLAINS.... ...SUMMARY... Isolated to scattered severe thunderstorms are possible today across portions of the Ohio and Tennessee Valleys into the central/southern Appalachians. A few strong/severe storms are also possible across portions of the southern Plains. ...Ohio and Tennessee Valleys to southern Appalachians... Positive-tilt short-wave trough is ejecting east across the mid MS Valley early this morning. This feature is gradually deamplifying as it's kicked downstream in advance of an upstream short-wave trough that's digging across the Plains. As a result, 500mb flow should increase across the TN/OH Valley region, and high-level flow will become increasingly diffluent. Early this morning, an elongated corridor of convection continues ahead of this feature, extending from southwest IN into southeast MO. Some form of this activity will likely be ongoing at the start of the period, immediately ahead of the front. While the early-day convection should not be particularly robust, boundary-layer heating should aid destabilization, especially south of the OH River where 0-3km lapse rates should steepen by 18z allowing MLCAPE values to increase to 1000-2000 J/kg. While deep-layer flow will be decidedly southwesterly, effective shear will be more than adequate for sustaining longer-lived clusters and even a few supercells. Forecast soundings suggest convection should develop fairly early in the period as mid-level lapse rates are poor, but convective temperatures will be breached quickly with temperatures rising through the 70s to near 80F. Primary concern with these storms will be damaging winds. ...Southern Plains... Upper ridge is forecast to build east into the Rockies during the day1 period, but this will allow a strong upper trough to dig south-southeast across the Plains as a 500mb speed max translates down the back side into western KS by 25/00z. Left exit region of this feature will encourage large-scale ascent, and a weak surface wave/low should evolve over southwest KS/northwest OK by early afternoon. This evolution will result in strong boundary-layer heating across the TX South Plains into northwest OK. Forecast soundings suggest 0-3km lapse rates will approach dry adiabatic by 21z, and convective temperatures will be breached in the upper 80s to near 90F. While LLJ is not expected to be particularly noteworthy, profiles across northwest into central OK will favor supercells as low-level flow will be decidedly southeasterly through 1km, and effective shear will be strong (50kt). Additionally, MLCAPE values in excess of 1000 J/kg should support robust updrafts. Will introduce low severe probabilities for hail/wind for supercells that evolve during the mid-late afternoon. This activity will spread south-southeast during the evening hours in advance of the digging short wave. Will continue to monitor this region, but at this time coverage of severe may not warrant higher probabilities. ..Darrow/Thornton.. 09/24/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1232 AM CDT Tue Sep 24 2024 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE TENNESSEE AND OHIO VALLEYS INTO THE SOUTHERN APPALACHIANS. A FEW STRONG/SEVERE STORMS ARE ALSO POSSIBLE OVER THE SOUTHERN PLAINS.... ...SUMMARY... Isolated to scattered severe thunderstorms are possible today across portions of the Ohio and Tennessee Valleys into the central/southern Appalachians. A few strong/severe storms are also possible across portions of the southern Plains. ...Ohio and Tennessee Valleys to southern Appalachians... Positive-tilt short-wave trough is ejecting east across the mid MS Valley early this morning. This feature is gradually deamplifying as it's kicked downstream in advance of an upstream short-wave trough that's digging across the Plains. As a result, 500mb flow should increase across the TN/OH Valley region, and high-level flow will become increasingly diffluent. Early this morning, an elongated corridor of convection continues ahead of this feature, extending from southwest IN into southeast MO. Some form of this activity will likely be ongoing at the start of the period, immediately ahead of the front. While the early-day convection should not be particularly robust, boundary-layer heating should aid destabilization, especially south of the OH River where 0-3km lapse rates should steepen by 18z allowing MLCAPE values to increase to 1000-2000 J/kg. While deep-layer flow will be decidedly southwesterly, effective shear will be more than adequate for sustaining longer-lived clusters and even a few supercells. Forecast soundings suggest convection should develop fairly early in the period as mid-level lapse rates are poor, but convective temperatures will be breached quickly with temperatures rising through the 70s to near 80F. Primary concern with these storms will be damaging winds. ...Southern Plains... Upper ridge is forecast to build east into the Rockies during the day1 period, but this will allow a strong upper trough to dig south-southeast across the Plains as a 500mb speed max translates down the back side into western KS by 25/00z. Left exit region of this feature will encourage large-scale ascent, and a weak surface wave/low should evolve over southwest KS/northwest OK by early afternoon. This evolution will result in strong boundary-layer heating across the TX South Plains into northwest OK. Forecast soundings suggest 0-3km lapse rates will approach dry adiabatic by 21z, and convective temperatures will be breached in the upper 80s to near 90F. While LLJ is not expected to be particularly noteworthy, profiles across northwest into central OK will favor supercells as low-level flow will be decidedly southeasterly through 1km, and effective shear will be strong (50kt). Additionally, MLCAPE values in excess of 1000 J/kg should support robust updrafts. Will introduce low severe probabilities for hail/wind for supercells that evolve during the mid-late afternoon. This activity will spread south-southeast during the evening hours in advance of the digging short wave. Will continue to monitor this region, but at this time coverage of severe may not warrant higher probabilities. ..Darrow/Thornton.. 09/24/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1232 AM CDT Tue Sep 24 2024 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE TENNESSEE AND OHIO VALLEYS INTO THE SOUTHERN APPALACHIANS. A FEW STRONG/SEVERE STORMS ARE ALSO POSSIBLE OVER THE SOUTHERN PLAINS.... ...SUMMARY... Isolated to scattered severe thunderstorms are possible today across portions of the Ohio and Tennessee Valleys into the central/southern Appalachians. A few strong/severe storms are also possible across portions of the southern Plains. ...Ohio and Tennessee Valleys to southern Appalachians... Positive-tilt short-wave trough is ejecting east across the mid MS Valley early this morning. This feature is gradually deamplifying as it's kicked downstream in advance of an upstream short-wave trough that's digging across the Plains. As a result, 500mb flow should increase across the TN/OH Valley region, and high-level flow will become increasingly diffluent. Early this morning, an elongated corridor of convection continues ahead of this feature, extending from southwest IN into southeast MO. Some form of this activity will likely be ongoing at the start of the period, immediately ahead of the front. While the early-day convection should not be particularly robust, boundary-layer heating should aid destabilization, especially south of the OH River where 0-3km lapse rates should steepen by 18z allowing MLCAPE values to increase to 1000-2000 J/kg. While deep-layer flow will be decidedly southwesterly, effective shear will be more than adequate for sustaining longer-lived clusters and even a few supercells. Forecast soundings suggest convection should develop fairly early in the period as mid-level lapse rates are poor, but convective temperatures will be breached quickly with temperatures rising through the 70s to near 80F. Primary concern with these storms will be damaging winds. ...Southern Plains... Upper ridge is forecast to build east into the Rockies during the day1 period, but this will allow a strong upper trough to dig south-southeast across the Plains as a 500mb speed max translates down the back side into western KS by 25/00z. Left exit region of this feature will encourage large-scale ascent, and a weak surface wave/low should evolve over southwest KS/northwest OK by early afternoon. This evolution will result in strong boundary-layer heating across the TX South Plains into northwest OK. Forecast soundings suggest 0-3km lapse rates will approach dry adiabatic by 21z, and convective temperatures will be breached in the upper 80s to near 90F. While LLJ is not expected to be particularly noteworthy, profiles across northwest into central OK will favor supercells as low-level flow will be decidedly southeasterly through 1km, and effective shear will be strong (50kt). Additionally, MLCAPE values in excess of 1000 J/kg should support robust updrafts. Will introduce low severe probabilities for hail/wind for supercells that evolve during the mid-late afternoon. This activity will spread south-southeast during the evening hours in advance of the digging short wave. Will continue to monitor this region, but at this time coverage of severe may not warrant higher probabilities. ..Darrow/Thornton.. 09/24/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1232 AM CDT Tue Sep 24 2024 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE TENNESSEE AND OHIO VALLEYS INTO THE SOUTHERN APPALACHIANS. A FEW STRONG/SEVERE STORMS ARE ALSO POSSIBLE OVER THE SOUTHERN PLAINS.... ...SUMMARY... Isolated to scattered severe thunderstorms are possible today across portions of the Ohio and Tennessee Valleys into the central/southern Appalachians. A few strong/severe storms are also possible across portions of the southern Plains. ...Ohio and Tennessee Valleys to southern Appalachians... Positive-tilt short-wave trough is ejecting east across the mid MS Valley early this morning. This feature is gradually deamplifying as it's kicked downstream in advance of an upstream short-wave trough that's digging across the Plains. As a result, 500mb flow should increase across the TN/OH Valley region, and high-level flow will become increasingly diffluent. Early this morning, an elongated corridor of convection continues ahead of this feature, extending from southwest IN into southeast MO. Some form of this activity will likely be ongoing at the start of the period, immediately ahead of the front. While the early-day convection should not be particularly robust, boundary-layer heating should aid destabilization, especially south of the OH River where 0-3km lapse rates should steepen by 18z allowing MLCAPE values to increase to 1000-2000 J/kg. While deep-layer flow will be decidedly southwesterly, effective shear will be more than adequate for sustaining longer-lived clusters and even a few supercells. Forecast soundings suggest convection should develop fairly early in the period as mid-level lapse rates are poor, but convective temperatures will be breached quickly with temperatures rising through the 70s to near 80F. Primary concern with these storms will be damaging winds. ...Southern Plains... Upper ridge is forecast to build east into the Rockies during the day1 period, but this will allow a strong upper trough to dig south-southeast across the Plains as a 500mb speed max translates down the back side into western KS by 25/00z. Left exit region of this feature will encourage large-scale ascent, and a weak surface wave/low should evolve over southwest KS/northwest OK by early afternoon. This evolution will result in strong boundary-layer heating across the TX South Plains into northwest OK. Forecast soundings suggest 0-3km lapse rates will approach dry adiabatic by 21z, and convective temperatures will be breached in the upper 80s to near 90F. While LLJ is not expected to be particularly noteworthy, profiles across northwest into central OK will favor supercells as low-level flow will be decidedly southeasterly through 1km, and effective shear will be strong (50kt). Additionally, MLCAPE values in excess of 1000 J/kg should support robust updrafts. Will introduce low severe probabilities for hail/wind for supercells that evolve during the mid-late afternoon. This activity will spread south-southeast during the evening hours in advance of the digging short wave. Will continue to monitor this region, but at this time coverage of severe may not warrant higher probabilities. ..Darrow/Thornton.. 09/24/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1232 AM CDT Tue Sep 24 2024 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE TENNESSEE AND OHIO VALLEYS INTO THE SOUTHERN APPALACHIANS. A FEW STRONG/SEVERE STORMS ARE ALSO POSSIBLE OVER THE SOUTHERN PLAINS.... ...SUMMARY... Isolated to scattered severe thunderstorms are possible today across portions of the Ohio and Tennessee Valleys into the central/southern Appalachians. A few strong/severe storms are also possible across portions of the southern Plains. ...Ohio and Tennessee Valleys to southern Appalachians... Positive-tilt short-wave trough is ejecting east across the mid MS Valley early this morning. This feature is gradually deamplifying as it's kicked downstream in advance of an upstream short-wave trough that's digging across the Plains. As a result, 500mb flow should increase across the TN/OH Valley region, and high-level flow will become increasingly diffluent. Early this morning, an elongated corridor of convection continues ahead of this feature, extending from southwest IN into southeast MO. Some form of this activity will likely be ongoing at the start of the period, immediately ahead of the front. While the early-day convection should not be particularly robust, boundary-layer heating should aid destabilization, especially south of the OH River where 0-3km lapse rates should steepen by 18z allowing MLCAPE values to increase to 1000-2000 J/kg. While deep-layer flow will be decidedly southwesterly, effective shear will be more than adequate for sustaining longer-lived clusters and even a few supercells. Forecast soundings suggest convection should develop fairly early in the period as mid-level lapse rates are poor, but convective temperatures will be breached quickly with temperatures rising through the 70s to near 80F. Primary concern with these storms will be damaging winds. ...Southern Plains... Upper ridge is forecast to build east into the Rockies during the day1 period, but this will allow a strong upper trough to dig south-southeast across the Plains as a 500mb speed max translates down the back side into western KS by 25/00z. Left exit region of this feature will encourage large-scale ascent, and a weak surface wave/low should evolve over southwest KS/northwest OK by early afternoon. This evolution will result in strong boundary-layer heating across the TX South Plains into northwest OK. Forecast soundings suggest 0-3km lapse rates will approach dry adiabatic by 21z, and convective temperatures will be breached in the upper 80s to near 90F. While LLJ is not expected to be particularly noteworthy, profiles across northwest into central OK will favor supercells as low-level flow will be decidedly southeasterly through 1km, and effective shear will be strong (50kt). Additionally, MLCAPE values in excess of 1000 J/kg should support robust updrafts. Will introduce low severe probabilities for hail/wind for supercells that evolve during the mid-late afternoon. This activity will spread south-southeast during the evening hours in advance of the digging short wave. Will continue to monitor this region, but at this time coverage of severe may not warrant higher probabilities. ..Darrow/Thornton.. 09/24/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1232 AM CDT Tue Sep 24 2024 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE TENNESSEE AND OHIO VALLEYS INTO THE SOUTHERN APPALACHIANS. A FEW STRONG/SEVERE STORMS ARE ALSO POSSIBLE OVER THE SOUTHERN PLAINS.... ...SUMMARY... Isolated to scattered severe thunderstorms are possible today across portions of the Ohio and Tennessee Valleys into the central/southern Appalachians. A few strong/severe storms are also possible across portions of the southern Plains. ...Ohio and Tennessee Valleys to southern Appalachians... Positive-tilt short-wave trough is ejecting east across the mid MS Valley early this morning. This feature is gradually deamplifying as it's kicked downstream in advance of an upstream short-wave trough that's digging across the Plains. As a result, 500mb flow should increase across the TN/OH Valley region, and high-level flow will become increasingly diffluent. Early this morning, an elongated corridor of convection continues ahead of this feature, extending from southwest IN into southeast MO. Some form of this activity will likely be ongoing at the start of the period, immediately ahead of the front. While the early-day convection should not be particularly robust, boundary-layer heating should aid destabilization, especially south of the OH River where 0-3km lapse rates should steepen by 18z allowing MLCAPE values to increase to 1000-2000 J/kg. While deep-layer flow will be decidedly southwesterly, effective shear will be more than adequate for sustaining longer-lived clusters and even a few supercells. Forecast soundings suggest convection should develop fairly early in the period as mid-level lapse rates are poor, but convective temperatures will be breached quickly with temperatures rising through the 70s to near 80F. Primary concern with these storms will be damaging winds. ...Southern Plains... Upper ridge is forecast to build east into the Rockies during the day1 period, but this will allow a strong upper trough to dig south-southeast across the Plains as a 500mb speed max translates down the back side into western KS by 25/00z. Left exit region of this feature will encourage large-scale ascent, and a weak surface wave/low should evolve over southwest KS/northwest OK by early afternoon. This evolution will result in strong boundary-layer heating across the TX South Plains into northwest OK. Forecast soundings suggest 0-3km lapse rates will approach dry adiabatic by 21z, and convective temperatures will be breached in the upper 80s to near 90F. While LLJ is not expected to be particularly noteworthy, profiles across northwest into central OK will favor supercells as low-level flow will be decidedly southeasterly through 1km, and effective shear will be strong (50kt). Additionally, MLCAPE values in excess of 1000 J/kg should support robust updrafts. Will introduce low severe probabilities for hail/wind for supercells that evolve during the mid-late afternoon. This activity will spread south-southeast during the evening hours in advance of the digging short wave. Will continue to monitor this region, but at this time coverage of severe may not warrant higher probabilities. ..Darrow/Thornton.. 09/24/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1232 AM CDT Tue Sep 24 2024 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE TENNESSEE AND OHIO VALLEYS INTO THE SOUTHERN APPALACHIANS. A FEW STRONG/SEVERE STORMS ARE ALSO POSSIBLE OVER THE SOUTHERN PLAINS.... ...SUMMARY... Isolated to scattered severe thunderstorms are possible today across portions of the Ohio and Tennessee Valleys into the central/southern Appalachians. A few strong/severe storms are also possible across portions of the southern Plains. ...Ohio and Tennessee Valleys to southern Appalachians... Positive-tilt short-wave trough is ejecting east across the mid MS Valley early this morning. This feature is gradually deamplifying as it's kicked downstream in advance of an upstream short-wave trough that's digging across the Plains. As a result, 500mb flow should increase across the TN/OH Valley region, and high-level flow will become increasingly diffluent. Early this morning, an elongated corridor of convection continues ahead of this feature, extending from southwest IN into southeast MO. Some form of this activity will likely be ongoing at the start of the period, immediately ahead of the front. While the early-day convection should not be particularly robust, boundary-layer heating should aid destabilization, especially south of the OH River where 0-3km lapse rates should steepen by 18z allowing MLCAPE values to increase to 1000-2000 J/kg. While deep-layer flow will be decidedly southwesterly, effective shear will be more than adequate for sustaining longer-lived clusters and even a few supercells. Forecast soundings suggest convection should develop fairly early in the period as mid-level lapse rates are poor, but convective temperatures will be breached quickly with temperatures rising through the 70s to near 80F. Primary concern with these storms will be damaging winds. ...Southern Plains... Upper ridge is forecast to build east into the Rockies during the day1 period, but this will allow a strong upper trough to dig south-southeast across the Plains as a 500mb speed max translates down the back side into western KS by 25/00z. Left exit region of this feature will encourage large-scale ascent, and a weak surface wave/low should evolve over southwest KS/northwest OK by early afternoon. This evolution will result in strong boundary-layer heating across the TX South Plains into northwest OK. Forecast soundings suggest 0-3km lapse rates will approach dry adiabatic by 21z, and convective temperatures will be breached in the upper 80s to near 90F. While LLJ is not expected to be particularly noteworthy, profiles across northwest into central OK will favor supercells as low-level flow will be decidedly southeasterly through 1km, and effective shear will be strong (50kt). Additionally, MLCAPE values in excess of 1000 J/kg should support robust updrafts. Will introduce low severe probabilities for hail/wind for supercells that evolve during the mid-late afternoon. This activity will spread south-southeast during the evening hours in advance of the digging short wave. Will continue to monitor this region, but at this time coverage of severe may not warrant higher probabilities. ..Darrow/Thornton.. 09/24/2024 Read more

The pumpkins at The Hermitage, Andrew Jackson’s historic home in Nashville, were growing, thanks to irrigation amid the drought. Then hungry deer came and devoured the pumpkins and corn. Officials with The Hermitage sought to buy pumpkins from elsewhere so they could still have a pumpkin carving event, but, finding none to purchase, the event was cancelled. Eventually, 100 pumpkins were donated so the event could go on. Similarly, the deer devastated the cotton crops in 2023. News Channel 5 Nashville (Tenn.), Sept 23, 2024

The Village of Middlefield passed a mandatory water conservation moratorium on Thursday, September 19 that allows water users to only use water for essential needs. Non-essential water uses like car washing, plant watering and swimming pool filling are not permitted. The LaDue Reservoir was getting very low. Cleveland 19 Online (Ohio), Sept 23, 2024

Issued at 920 PM CST Mon Sep 23 2024 128 WTPZ65 KNHC 240322 TCUEP5 Hurricane John Tropical Cyclone Update NWS National Hurricane Center Miami FL EP102024 920 PM CST Mon Sep 23 2024 ...MAJOR HURRICANE JOHN MAKES LANDFALL IN MEXICO... Satellite data indicates that Hurricane John has made landfall along the southern coast of Mexico just to the south-southwest of Marquelia, Mexico in the state of Guerrero at around 915 PM CST (0315 UTC). The maximum sustained winds at landfall are estimated to be 120 mph (195 km/h), and the minimum central pressure is estimated at 959 mb (28.32 inches). This makes John a category 3 hurricane on the Saffir-Simpson Hurricane Wind Scale. SUMMARY OF 920 PM CST...0320 UTC...INFORMATION --------------------------------------------------- LOCATION...16.6N 98.9W ABOUT 25 MI...40 KM NW OF PUNTA MALDONADO MEXICO ABOUT 130 MI...205 KM WNW OF PUERTO ESCONDIDO MEXICO MAXIMUM SUSTAINED WINDS...120 MPH...195 KM/H PRESENT MOVEMENT...N OR 350 DEGREES AT 8 MPH...13 KM/H MINIMUM CENTRAL PRESSURE...959 MB...28.32 INCHES $$ Forecaster Papin

...JOHN NOW A TROPICAL STORM AND MOVING NORTHWESTWARD... ...LIFE-THREATENING FLASH FLOODING TO CONTINUE ALONG SOUTHERN MEXICAN COAST FOR THE NEXT FEW DAYS... As of 3:00 AM CST Tue Sep 24 the center of John was located near 17.3, -100.0 with movement NW at 8 mph. The minimum central pressure was 990 mb with maximum sustained winds of about 70 mph.

5-Day Uncertainty Track last updated Tue, 24 Sep 2024 02:34:13 GMT


Wind Speed Probabilities last updated Tue, 24 Sep 2024 03:29:28 GMT

Issued at 900 PM CST Mon Sep 23 2024 210 WTPZ45 KNHC 240233 TCDEP5 Hurricane John Discussion Number 7 NWS National Hurricane Center Miami FL EP102024 900 PM CST Mon Sep 23 2024 John has continued to strengthen this evening with a small tight inner core, which was well depicted in SSMIS microwave images around 00z. Infrared imagery depicts an eye with cold cloud tops near -80 C wrapping around the core. Subjective intensity estimates have continued to increase this evening with data-T values of T5.5 from both SAB and TAFB, with final-T values constrained due to the rapid intensification. Given the most recent satellite depiction and using the data-T values, the intensity for this advisory is increased to 105 kt. John is now a major category 3 hurricane. The hurricane could still strengthen some more over the next couple of hours before it makes landfall along the coast of southern Mexico. After John moves inland, rapid weakening is forecast over the higher terrain with the small inner core quickly deteriorating. The rate of weakening could occur faster than what is currently forecast and the 24 h forecast point is held for continuity inland as it is possible the system could dissipate sooner. John continues to move northward around 7 kt. This current motion should continue as John nears the coast, making landfall in the next couple of hours and will continue to move inland on Tuesday. The cyclone is forecast to slow its forward motion as it moves inland and dissipates. KEY MESSAGES: 1. John is expected to be a major hurricane as it reaches the coast of southern Mexico within the Hurricane Warning area in the next couple of hours. Damaging hurricane-force winds and a life-threatening storm surge are expected within portions of the hurricane warning area. 2. Slow-moving Hurricane John will bring very heavy rainfall to coastal portions of southwest Mexico through the upcoming week. This heavy rainfall will likely cause significant and possibly catastrophic, life-threatening flash flooding and mudslides to the Mexican States of Chiapas, Oaxaca, and southeast Guerrero, particularly in areas near the coast. FORECAST POSITIONS AND MAX WINDS INIT 24/0300Z 16.3N 98.8W 105 KT 120 MPH 12H 24/1200Z 17.0N 98.9W 55 KT 65 MPH...INLAND 24H 25/0000Z 17.5N 99.1W 25 KT 30 MPH...POST-TROP/INLAND 36H 25/1200Z...DISSIPATED $$ Forecaster Kelly

Issued at 0300 UTC TUE SEP 24 2024 000 FOPZ15 KNHC 240232 PWSEP5 HURRICANE JOHN WIND SPEED PROBABILITIES NUMBER 7 NWS NATIONAL HURRICANE CENTER MIAMI FL EP102024 0300 UTC TUE SEP 24 2024 AT 0300Z THE CENTER OF HURRICANE JOHN WAS LOCATED NEAR LATITUDE 16.3 NORTH...LONGITUDE 98.8 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 105 KTS...120 MPH...195 KM/H. Z INDICATES COORDINATED UNIVERSAL TIME (GREENWICH) PACIFIC DAYLIGHT TIME (PDT)...SUBTRACT 7 HOURS FROM Z TIME HAWAIIAN STANDARD TIME (HST)...SUBTRACT 10 HOURS FROM Z TIME WIND SPEED PROBABILITY TABLE FOR SPECIFIC LOCATIONS CHANCES OF SUSTAINED (1-MINUTE AVERAGE) WIND SPEEDS OF AT LEAST ...34 KT (39 MPH... 63 KM/H)... ...50 KT (58 MPH... 93 KM/H)... ...64 KT (74 MPH...119 KM/H)... FOR LOCATIONS AND TIME PERIODS DURING THE NEXT 5 DAYS PROBABILITIES FOR LOCATIONS ARE GIVEN AS OP(CP) WHERE OP IS THE PROBABILITY OF THE EVENT BEGINNING DURING AN INDIVIDUAL TIME PERIOD (ONSET PROBABILITY) (CP) IS THE PROBABILITY OF THE EVENT OCCURRING BETWEEN 00Z TUE AND THE FORECAST HOUR (CUMULATIVE PROBABILITY) PROBABILITIES ARE GIVEN IN PERCENT X INDICATES PROBABILITIES LESS THAN 1 PERCENT PROBABILITIES FOR 34 KT AND 50 KT ARE SHOWN AT A GIVEN LOCATION WHEN THE 5-DAY CUMULATIVE PROBABILITY IS AT LEAST 3 PERCENT. PROBABILITIES FOR 34...50...64 KT SHOWN WHEN THE 5-DAY 64-KT CUMULATIVE PROBABILITY IS AT LEAST 1 PERCENT. - - - - WIND SPEED PROBABILITIES FOR SELECTED LOCATIONS - - - - FROM FROM FROM FROM FROM FROM FROM TIME 00Z TUE 12Z TUE 00Z WED 12Z WED 00Z THU 00Z FRI 00Z SAT PERIODS TO TO TO TO TO TO TO 12Z TUE 00Z WED 12Z WED 00Z THU 00Z FRI 00Z SAT 00Z SUN FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT ACAPULCO 34 9 2(11) X(11) X(11) X(11) X(11) X(11) P MALDONADO 34 99 X(99) X(99) X(99) X(99) X(99) X(99) P MALDONADO 50 96 1(97) X(97) X(97) X(97) X(97) X(97) P MALDONADO 64 51 1(52) X(52) X(52) X(52) X(52) X(52) $$ FORECASTER KELLY

Issued at 900 PM CST Mon Sep 23 2024 000 WTPZ35 KNHC 240232 TCPEP5 BULLETIN Hurricane John Advisory Number 7 NWS National Hurricane Center Miami FL EP102024 900 PM CST Mon Sep 23 2024 ...MAJOR HURRICANE JOHN VERY NEAR THE COAST... ...DAMAGING HURRICANE-FORCE WINDS, LIFE-THREATENING STORM SURGE AND FLASH FLOODING ARE ONGOING... SUMMARY OF 900 PM CST...0300 UTC...INFORMATION ---------------------------------------------- LOCATION...16.3N 98.8W ABOUT 15 MI...20 KM W OF PUNTA MALDONADO MEXICO ABOUT 120 MI...190 KM WNW OF PUERTO ESCONDIDO MEXICO MAXIMUM SUSTAINED WINDS...120 MPH...195 KM/H PRESENT MOVEMENT...N OR 350 DEGREES AT 8 MPH...13 KM/H MINIMUM CENTRAL PRESSURE...959 MB...28.32 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: None. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Hurricane Warning is in effect for... * East of Acapulco to Bahias de Huatulco A Tropical Storm Warning is in effect for... * East of Bahias de Huatulco to Salina Cruz A Hurricane Warning means that hurricane conditions are expected somewhere within the warning area, in this case within the next couple of hours. A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area, in this case within the next couple hours. For storm information specific to your area, please monitor products issued by your national meteorological service. DISCUSSION AND OUTLOOK ---------------------- At 900 PM CST (0300 UTC), the center of Hurricane John was located near latitude 16.3 North, longitude 98.8 West. John is moving toward the north near 8 mph (13 km/h). On the forecast track, the center of John is forecast to move inland along the coast of southern Mexico in the next couple of hours. John will continue to move inland over southern Mexico on Tuesday. Maximum sustained winds have increased to near 120 mph (195 km/h) with higher gusts. John is now a category 3 hurricane on the Saffir-Simpson Hurricane Wind Scale. Some additional strengthening is possible the next couple of hours before John makes landfall. After landfall, the system will rapidly weaken over the high terrain of southern Mexico. Hurricane-force winds extend outward up to 10 miles (20 km) from the center and tropical-storm-force winds extend outward up to 45 miles (75 km). The estimated minimum central pressure is 959 mb (28.32 inches). HAZARDS AFFECTING LAND ---------------------- Key Messages for John can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDEP5 and WMO header WTPZ45 KNHC and on the web at hurricanes.gov/text/MIATCDEP5.shtml RAINFALL: Through Thursday, Hurricane John is expected to produce 6 to 12 inches of rain with isolated totals around 15 inches across the coastal areas of Chiapas. In areas along and near the Oaxaca coast to southeast Guerrero, between 10 and 20 inches of rain with isolated totals near 30 inches can be expected through Thursday. For a complete depiction of forecast rainfall associated with Hurricane John, please see the National Weather Service Storm Total Rainfall Graphic, available at hurricanes.gov/graphics_ep5.shtml?rainqpf STORM SURGE: A life-threatening storm surge is expected to produce significant coastal flooding near and to the east of where the center makes landfall. Near the coast, the surge will be accompanied by large and destructive waves. WIND: Hurricane conditions are ongoing within portions of the hurricane warning area. Tropical-storm-force winds are already occuring within the warning area. Wind speeds atop and on the windward sides of hills and mountains are often up to 30 percent stronger than the near-surface winds indicated in this advisory, and in some elevated locations could be even greater. SURF: Swells associated with John are forecast to continue affecting the coast of southern Mexico during the next couple of days, with the potential for dangerous surf and rip currents much of the week. Please see local statements for more information. NEXT ADVISORY ------------- Next intermediate advisory at 1200 AM CST. Next complete advisory at 300 AM CST. $$ Forecaster Kelly

...MAJOR HURRICANE JOHN VERY NEAR THE COAST... ...DAMAGING HURRICANE-FORCE WINDS, LIFE-THREATENING STORM SURGE AND FLASH FLOODING ARE ONGOING... As of 9:00 PM CST Mon Sep 23 the center of John was located near 16.3, -98.8 with movement N at 8 mph. The minimum central pressure was 959 mb with maximum sustained winds of about 120 mph.