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SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0647 AM CST Wed Nov 22 2023 Valid 221300Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PORTIONS OF EASTERN NORTH CAROLINA AND THE OUTER BANKS... ...SUMMARY... A brief tornado and localized damaging-gust threat are possible this morning across portions of eastern North Carolina and the Outer Banks. ...Synopsis... A progressive mid/upper-level pattern will remain in place through the period, except for a split-flow regime around a cut-off low over northwestern MX. Farther northeast, a nearly closed 500-mb low was apparent in moisture-channel imagery over the Mid-South, anchoring an intense shortwave trough that extended south-southwestward over parts of LA. The low and trough are pivoting eastward and should cross the Tennessee Valley and southern Appalachians today, reaching the NC/SC Piedmont by 00Z. The perturbation then should race offshore. At the surface, a cold front was analyzed at 11Z from NJ to a frontal wave over north-central NC, then across central SC, eastern GA, the FL coastal-bend area, and northeastern Gulf. The front is expected to move offshore from NC around 17-18Z, while crossing parts of north FL. The front should reach central/southwestern FL around 00Z, and move off south FL and the Keys by 12Z. ...Eastern NC... A marginal tornado and severe-wind threat remains over this area for a few more hours, especially ahead of the front, and perhaps until convection along the front passes. See SPC mesoscale discussion 2285 for near-term details. The approaching shortwave trough and related mass response may increase both low-level lift and large-scale ascent over the area through midday, while maintaining somewhat veered but enlarged low-level hodographs (as seen in the 12Z MHX RAOB), along with moisture transport/theta-e advection near the coast. Meanwhile, strengthening mid/upper winds will help to offset some veering of surface flow in maintaining favorable deep shear for supercells, and/or organized line(s) of convection with embedded areas of at least transient rotation. Messy convective mode and lack of greater buoyancy (due to weak deep-layer lapse rates) over land will be limiting factors for severe potential. ..Edwards/Broyles.. 11/22/2023 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0647 AM CST Wed Nov 22 2023 Valid 221300Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PORTIONS OF EASTERN NORTH CAROLINA AND THE OUTER BANKS... ...SUMMARY... A brief tornado and localized damaging-gust threat are possible this morning across portions of eastern North Carolina and the Outer Banks. ...Synopsis... A progressive mid/upper-level pattern will remain in place through the period, except for a split-flow regime around a cut-off low over northwestern MX. Farther northeast, a nearly closed 500-mb low was apparent in moisture-channel imagery over the Mid-South, anchoring an intense shortwave trough that extended south-southwestward over parts of LA. The low and trough are pivoting eastward and should cross the Tennessee Valley and southern Appalachians today, reaching the NC/SC Piedmont by 00Z. The perturbation then should race offshore. At the surface, a cold front was analyzed at 11Z from NJ to a frontal wave over north-central NC, then across central SC, eastern GA, the FL coastal-bend area, and northeastern Gulf. The front is expected to move offshore from NC around 17-18Z, while crossing parts of north FL. The front should reach central/southwestern FL around 00Z, and move off south FL and the Keys by 12Z. ...Eastern NC... A marginal tornado and severe-wind threat remains over this area for a few more hours, especially ahead of the front, and perhaps until convection along the front passes. See SPC mesoscale discussion 2285 for near-term details. The approaching shortwave trough and related mass response may increase both low-level lift and large-scale ascent over the area through midday, while maintaining somewhat veered but enlarged low-level hodographs (as seen in the 12Z MHX RAOB), along with moisture transport/theta-e advection near the coast. Meanwhile, strengthening mid/upper winds will help to offset some veering of surface flow in maintaining favorable deep shear for supercells, and/or organized line(s) of convection with embedded areas of at least transient rotation. Messy convective mode and lack of greater buoyancy (due to weak deep-layer lapse rates) over land will be limiting factors for severe potential. ..Edwards/Broyles.. 11/22/2023 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0647 AM CST Wed Nov 22 2023 Valid 221300Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PORTIONS OF EASTERN NORTH CAROLINA AND THE OUTER BANKS... ...SUMMARY... A brief tornado and localized damaging-gust threat are possible this morning across portions of eastern North Carolina and the Outer Banks. ...Synopsis... A progressive mid/upper-level pattern will remain in place through the period, except for a split-flow regime around a cut-off low over northwestern MX. Farther northeast, a nearly closed 500-mb low was apparent in moisture-channel imagery over the Mid-South, anchoring an intense shortwave trough that extended south-southwestward over parts of LA. The low and trough are pivoting eastward and should cross the Tennessee Valley and southern Appalachians today, reaching the NC/SC Piedmont by 00Z. The perturbation then should race offshore. At the surface, a cold front was analyzed at 11Z from NJ to a frontal wave over north-central NC, then across central SC, eastern GA, the FL coastal-bend area, and northeastern Gulf. The front is expected to move offshore from NC around 17-18Z, while crossing parts of north FL. The front should reach central/southwestern FL around 00Z, and move off south FL and the Keys by 12Z. ...Eastern NC... A marginal tornado and severe-wind threat remains over this area for a few more hours, especially ahead of the front, and perhaps until convection along the front passes. See SPC mesoscale discussion 2285 for near-term details. The approaching shortwave trough and related mass response may increase both low-level lift and large-scale ascent over the area through midday, while maintaining somewhat veered but enlarged low-level hodographs (as seen in the 12Z MHX RAOB), along with moisture transport/theta-e advection near the coast. Meanwhile, strengthening mid/upper winds will help to offset some veering of surface flow in maintaining favorable deep shear for supercells, and/or organized line(s) of convection with embedded areas of at least transient rotation. Messy convective mode and lack of greater buoyancy (due to weak deep-layer lapse rates) over land will be limiting factors for severe potential. ..Edwards/Broyles.. 11/22/2023 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0647 AM CST Wed Nov 22 2023 Valid 221300Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PORTIONS OF EASTERN NORTH CAROLINA AND THE OUTER BANKS... ...SUMMARY... A brief tornado and localized damaging-gust threat are possible this morning across portions of eastern North Carolina and the Outer Banks. ...Synopsis... A progressive mid/upper-level pattern will remain in place through the period, except for a split-flow regime around a cut-off low over northwestern MX. Farther northeast, a nearly closed 500-mb low was apparent in moisture-channel imagery over the Mid-South, anchoring an intense shortwave trough that extended south-southwestward over parts of LA. The low and trough are pivoting eastward and should cross the Tennessee Valley and southern Appalachians today, reaching the NC/SC Piedmont by 00Z. The perturbation then should race offshore. At the surface, a cold front was analyzed at 11Z from NJ to a frontal wave over north-central NC, then across central SC, eastern GA, the FL coastal-bend area, and northeastern Gulf. The front is expected to move offshore from NC around 17-18Z, while crossing parts of north FL. The front should reach central/southwestern FL around 00Z, and move off south FL and the Keys by 12Z. ...Eastern NC... A marginal tornado and severe-wind threat remains over this area for a few more hours, especially ahead of the front, and perhaps until convection along the front passes. See SPC mesoscale discussion 2285 for near-term details. The approaching shortwave trough and related mass response may increase both low-level lift and large-scale ascent over the area through midday, while maintaining somewhat veered but enlarged low-level hodographs (as seen in the 12Z MHX RAOB), along with moisture transport/theta-e advection near the coast. Meanwhile, strengthening mid/upper winds will help to offset some veering of surface flow in maintaining favorable deep shear for supercells, and/or organized line(s) of convection with embedded areas of at least transient rotation. Messy convective mode and lack of greater buoyancy (due to weak deep-layer lapse rates) over land will be limiting factors for severe potential. ..Edwards/Broyles.. 11/22/2023 Read more

MD 2285 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR EASTERN NORTH CAROLINA
Mesoscale Discussion 2285 NWS Storm Prediction Center Norman OK 0607 AM CST Wed Nov 22 2023 Areas affected...Eastern North Carolina Concerning...Severe potential...Watch unlikely Valid 221207Z - 221430Z Probability of Watch Issuance...20 percent SUMMARY...An isolated tornado threat is expected to develop across parts of eastern North Carolina this morning. The severe threat should remain marginal, and weather watch issuance is not expected. DISCUSSION...At mid-levels, a trough and an associated speed max, are located over the central Gulf Coast states. The 80 to 100 knot mid-level jet will continue to approach the Carolinas over the next few hours. As a result, large-scale ascent and deep-layer shear will gradually strengthen over the Carolinas this morning. At the surface, a mesoscale low is analyzed over northeastern South Carolina, with another in northeastern North Carolina. A weakly unstable airmass is present to the east of this surface trough. This airmass will slowly destabilize this morning, which will make conditions more favorable for rotating storms. In addition, the WSR-88D VWP near Wilmington, North Carolina currently has 0-3 km storm-relative helicity near 230 m2/s2. As the low-level shear strengthens ahead of the system, a marginal tornado threat is expected to develop. This threat should persist throughout the morning from near the coast of North Carolina inland about 50 statute miles. ..Broyles/Edwards.. 11/22/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MHX...RAH...ILM... LAT...LON 34957572 34107744 33967803 34057837 34317849 34677823 35747652 36047591 35927550 35447533 34957572 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0311 AM CST Wed Nov 22 2023 Valid 251200Z - 301200Z ...DISCUSSION... While guidance varies regarding synoptic-scale details (especially later in extended range), there is general agreement that broad upper-level troughing will cover most of the CONUS this weekend into next week, except for occasional upper ridging over the Northwest. Multiple frontal passages will tend to suppress the inland advance of Gulf moisture, and stable conditions will the potential for deep convection over most of the CONUS into next week. Thunderstorm potential may accompany occasional moisture return across areas near the TX Gulf Coast and also across the FL Peninsula. However, with stronger large-scale ascent and deep-layer flow/shear expected to remain displaced well north of favorable instability, severe-thunderstorm potential currently appears limited through the extended range. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0311 AM CST Wed Nov 22 2023 Valid 251200Z - 301200Z ...DISCUSSION... While guidance varies regarding synoptic-scale details (especially later in extended range), there is general agreement that broad upper-level troughing will cover most of the CONUS this weekend into next week, except for occasional upper ridging over the Northwest. Multiple frontal passages will tend to suppress the inland advance of Gulf moisture, and stable conditions will the potential for deep convection over most of the CONUS into next week. Thunderstorm potential may accompany occasional moisture return across areas near the TX Gulf Coast and also across the FL Peninsula. However, with stronger large-scale ascent and deep-layer flow/shear expected to remain displaced well north of favorable instability, severe-thunderstorm potential currently appears limited through the extended range. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0311 AM CST Wed Nov 22 2023 Valid 251200Z - 301200Z ...DISCUSSION... While guidance varies regarding synoptic-scale details (especially later in extended range), there is general agreement that broad upper-level troughing will cover most of the CONUS this weekend into next week, except for occasional upper ridging over the Northwest. Multiple frontal passages will tend to suppress the inland advance of Gulf moisture, and stable conditions will the potential for deep convection over most of the CONUS into next week. Thunderstorm potential may accompany occasional moisture return across areas near the TX Gulf Coast and also across the FL Peninsula. However, with stronger large-scale ascent and deep-layer flow/shear expected to remain displaced well north of favorable instability, severe-thunderstorm potential currently appears limited through the extended range. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0311 AM CST Wed Nov 22 2023 Valid 251200Z - 301200Z ...DISCUSSION... While guidance varies regarding synoptic-scale details (especially later in extended range), there is general agreement that broad upper-level troughing will cover most of the CONUS this weekend into next week, except for occasional upper ridging over the Northwest. Multiple frontal passages will tend to suppress the inland advance of Gulf moisture, and stable conditions will the potential for deep convection over most of the CONUS into next week. Thunderstorm potential may accompany occasional moisture return across areas near the TX Gulf Coast and also across the FL Peninsula. However, with stronger large-scale ascent and deep-layer flow/shear expected to remain displaced well north of favorable instability, severe-thunderstorm potential currently appears limited through the extended range. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0311 AM CST Wed Nov 22 2023 Valid 251200Z - 301200Z ...DISCUSSION... While guidance varies regarding synoptic-scale details (especially later in extended range), there is general agreement that broad upper-level troughing will cover most of the CONUS this weekend into next week, except for occasional upper ridging over the Northwest. Multiple frontal passages will tend to suppress the inland advance of Gulf moisture, and stable conditions will the potential for deep convection over most of the CONUS into next week. Thunderstorm potential may accompany occasional moisture return across areas near the TX Gulf Coast and also across the FL Peninsula. However, with stronger large-scale ascent and deep-layer flow/shear expected to remain displaced well north of favorable instability, severe-thunderstorm potential currently appears limited through the extended range. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0311 AM CST Wed Nov 22 2023 Valid 251200Z - 301200Z ...DISCUSSION... While guidance varies regarding synoptic-scale details (especially later in extended range), there is general agreement that broad upper-level troughing will cover most of the CONUS this weekend into next week, except for occasional upper ridging over the Northwest. Multiple frontal passages will tend to suppress the inland advance of Gulf moisture, and stable conditions will the potential for deep convection over most of the CONUS into next week. Thunderstorm potential may accompany occasional moisture return across areas near the TX Gulf Coast and also across the FL Peninsula. However, with stronger large-scale ascent and deep-layer flow/shear expected to remain displaced well north of favorable instability, severe-thunderstorm potential currently appears limited through the extended range. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0311 AM CST Wed Nov 22 2023 Valid 251200Z - 301200Z ...DISCUSSION... While guidance varies regarding synoptic-scale details (especially later in extended range), there is general agreement that broad upper-level troughing will cover most of the CONUS this weekend into next week, except for occasional upper ridging over the Northwest. Multiple frontal passages will tend to suppress the inland advance of Gulf moisture, and stable conditions will the potential for deep convection over most of the CONUS into next week. Thunderstorm potential may accompany occasional moisture return across areas near the TX Gulf Coast and also across the FL Peninsula. However, with stronger large-scale ascent and deep-layer flow/shear expected to remain displaced well north of favorable instability, severe-thunderstorm potential currently appears limited through the extended range. Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CST Wed Nov 22 2023 Valid 241200Z - 251200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm potential appears low on Friday. ...Synopsis... An upper-level low initially centered over Utah is forecast to gradually weaken and evolve into a positively tilted trough by late Friday, as an embedded shortwave moves from the Four Corners region toward the central High Plains. Weak convection may accompany wintry precipitation associated with this system, but thunderstorm potential will likely be limited by meager instability. The front that will move into the Gulf and across the FL Peninsula earlier this week is forecast to become nearly stationary, and then lift slowly northward as a warm front on Friday. Weak surface waves may develop along the front near the southeast FL coast, and also across the Gulf of Mexico. However, despite increasing moisture across parts of the FL Peninsula, poor midlevel lapse rates and scant buoyancy are currently expected to limit thunderstorm potential. ..Dean.. 11/22/2023 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CST Wed Nov 22 2023 Valid 241200Z - 251200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm potential appears low on Friday. ...Synopsis... An upper-level low initially centered over Utah is forecast to gradually weaken and evolve into a positively tilted trough by late Friday, as an embedded shortwave moves from the Four Corners region toward the central High Plains. Weak convection may accompany wintry precipitation associated with this system, but thunderstorm potential will likely be limited by meager instability. The front that will move into the Gulf and across the FL Peninsula earlier this week is forecast to become nearly stationary, and then lift slowly northward as a warm front on Friday. Weak surface waves may develop along the front near the southeast FL coast, and also across the Gulf of Mexico. However, despite increasing moisture across parts of the FL Peninsula, poor midlevel lapse rates and scant buoyancy are currently expected to limit thunderstorm potential. ..Dean.. 11/22/2023 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CST Wed Nov 22 2023 Valid 241200Z - 251200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm potential appears low on Friday. ...Synopsis... An upper-level low initially centered over Utah is forecast to gradually weaken and evolve into a positively tilted trough by late Friday, as an embedded shortwave moves from the Four Corners region toward the central High Plains. Weak convection may accompany wintry precipitation associated with this system, but thunderstorm potential will likely be limited by meager instability. The front that will move into the Gulf and across the FL Peninsula earlier this week is forecast to become nearly stationary, and then lift slowly northward as a warm front on Friday. Weak surface waves may develop along the front near the southeast FL coast, and also across the Gulf of Mexico. However, despite increasing moisture across parts of the FL Peninsula, poor midlevel lapse rates and scant buoyancy are currently expected to limit thunderstorm potential. ..Dean.. 11/22/2023 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CST Wed Nov 22 2023 Valid 241200Z - 251200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm potential appears low on Friday. ...Synopsis... An upper-level low initially centered over Utah is forecast to gradually weaken and evolve into a positively tilted trough by late Friday, as an embedded shortwave moves from the Four Corners region toward the central High Plains. Weak convection may accompany wintry precipitation associated with this system, but thunderstorm potential will likely be limited by meager instability. The front that will move into the Gulf and across the FL Peninsula earlier this week is forecast to become nearly stationary, and then lift slowly northward as a warm front on Friday. Weak surface waves may develop along the front near the southeast FL coast, and also across the Gulf of Mexico. However, despite increasing moisture across parts of the FL Peninsula, poor midlevel lapse rates and scant buoyancy are currently expected to limit thunderstorm potential. ..Dean.. 11/22/2023 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CST Wed Nov 22 2023 Valid 241200Z - 251200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm potential appears low on Friday. ...Synopsis... An upper-level low initially centered over Utah is forecast to gradually weaken and evolve into a positively tilted trough by late Friday, as an embedded shortwave moves from the Four Corners region toward the central High Plains. Weak convection may accompany wintry precipitation associated with this system, but thunderstorm potential will likely be limited by meager instability. The front that will move into the Gulf and across the FL Peninsula earlier this week is forecast to become nearly stationary, and then lift slowly northward as a warm front on Friday. Weak surface waves may develop along the front near the southeast FL coast, and also across the Gulf of Mexico. However, despite increasing moisture across parts of the FL Peninsula, poor midlevel lapse rates and scant buoyancy are currently expected to limit thunderstorm potential. ..Dean.. 11/22/2023 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CST Wed Nov 22 2023 Valid 241200Z - 251200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm potential appears low on Friday. ...Synopsis... An upper-level low initially centered over Utah is forecast to gradually weaken and evolve into a positively tilted trough by late Friday, as an embedded shortwave moves from the Four Corners region toward the central High Plains. Weak convection may accompany wintry precipitation associated with this system, but thunderstorm potential will likely be limited by meager instability. The front that will move into the Gulf and across the FL Peninsula earlier this week is forecast to become nearly stationary, and then lift slowly northward as a warm front on Friday. Weak surface waves may develop along the front near the southeast FL coast, and also across the Gulf of Mexico. However, despite increasing moisture across parts of the FL Peninsula, poor midlevel lapse rates and scant buoyancy are currently expected to limit thunderstorm potential. ..Dean.. 11/22/2023 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CST Wed Nov 22 2023 Valid 241200Z - 251200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm potential appears low on Friday. ...Synopsis... An upper-level low initially centered over Utah is forecast to gradually weaken and evolve into a positively tilted trough by late Friday, as an embedded shortwave moves from the Four Corners region toward the central High Plains. Weak convection may accompany wintry precipitation associated with this system, but thunderstorm potential will likely be limited by meager instability. The front that will move into the Gulf and across the FL Peninsula earlier this week is forecast to become nearly stationary, and then lift slowly northward as a warm front on Friday. Weak surface waves may develop along the front near the southeast FL coast, and also across the Gulf of Mexico. However, despite increasing moisture across parts of the FL Peninsula, poor midlevel lapse rates and scant buoyancy are currently expected to limit thunderstorm potential. ..Dean.. 11/22/2023 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CST Wed Nov 22 2023 Valid 241200Z - 251200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm potential appears low on Friday. ...Synopsis... An upper-level low initially centered over Utah is forecast to gradually weaken and evolve into a positively tilted trough by late Friday, as an embedded shortwave moves from the Four Corners region toward the central High Plains. Weak convection may accompany wintry precipitation associated with this system, but thunderstorm potential will likely be limited by meager instability. The front that will move into the Gulf and across the FL Peninsula earlier this week is forecast to become nearly stationary, and then lift slowly northward as a warm front on Friday. Weak surface waves may develop along the front near the southeast FL coast, and also across the Gulf of Mexico. However, despite increasing moisture across parts of the FL Peninsula, poor midlevel lapse rates and scant buoyancy are currently expected to limit thunderstorm potential. ..Dean.. 11/22/2023 Read more