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SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1240 AM CDT Sat Apr 13 2024 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF PA TO EAST OH... ...SUMMARY... Isolated to scattered severe thunderstorms are possible from late afternoon into the evening on Sunday, across eastern Indiana into the Northeast States. Damaging winds should be the primary hazard, but a tornado or two and large hail are also possible. ...Northeast States to eastern IN... A mid-level jetlet attendant to a low-amplitude shortwave impulse should progress across the northern Great Lakes and Ontario into New England by Sunday evening. Weak cyclogenesis should occur with the surface low tracking east across parts of NY. An attendant cold front should arc westward and progress southeastward. A pronounced elevated mixed layer across the Midwest and southern Great Lakes will shift southeastward into the Mid-Atlantic and Southeast States. This elevated mixed layer will likely cap surface-based convection until near/after peak heating along the west/east-oriented cold front. 00Z RRFS/NAM soundings appear relatively reasonable with this evolution as modified low-level moisture return emanating from the southern Great Plains struggles to reduce MLCIN until cooling aloft advects in from the west-northwest. Other guidance may be too moist within the boundary layer given upstream observations and 36 hours of air mass modification remaining. Still, a corridor of MLCAPE reaching 1000-1500 J/kg will probably develop in IN/OH given the initially steep mid-level lapse rates. This buoyancy plume will subside with eastern extent towards the DE Valley. Hodographs across the region should be dominated by low-level curvature enlargement, especially with eastern extent. However, weak speed and directional shear components are expected above that within the buoyancy layer. Maturing cells will attempt to form supercell structures, but given the nearly parallel orientation of the front with respect to the deep-layer westerly flow regime, convective mode should favor west/east-oriented clusters. These should largely progress south-southeast amid the undercutting nature of the composite front and emerging convective outflows. Due to the initially steep mid-level lapse rates and enlarged low-level hodographs, there is concern for a brief supercell tornado and isolated hail threat. Though with the limiting factors, it appears damaging winds should be the primary hazard during the evening before convection wanes with southern extent overnight. ..Grams.. 04/13/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1240 AM CDT Sat Apr 13 2024 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF PA TO EAST OH... ...SUMMARY... Isolated to scattered severe thunderstorms are possible from late afternoon into the evening on Sunday, across eastern Indiana into the Northeast States. Damaging winds should be the primary hazard, but a tornado or two and large hail are also possible. ...Northeast States to eastern IN... A mid-level jetlet attendant to a low-amplitude shortwave impulse should progress across the northern Great Lakes and Ontario into New England by Sunday evening. Weak cyclogenesis should occur with the surface low tracking east across parts of NY. An attendant cold front should arc westward and progress southeastward. A pronounced elevated mixed layer across the Midwest and southern Great Lakes will shift southeastward into the Mid-Atlantic and Southeast States. This elevated mixed layer will likely cap surface-based convection until near/after peak heating along the west/east-oriented cold front. 00Z RRFS/NAM soundings appear relatively reasonable with this evolution as modified low-level moisture return emanating from the southern Great Plains struggles to reduce MLCIN until cooling aloft advects in from the west-northwest. Other guidance may be too moist within the boundary layer given upstream observations and 36 hours of air mass modification remaining. Still, a corridor of MLCAPE reaching 1000-1500 J/kg will probably develop in IN/OH given the initially steep mid-level lapse rates. This buoyancy plume will subside with eastern extent towards the DE Valley. Hodographs across the region should be dominated by low-level curvature enlargement, especially with eastern extent. However, weak speed and directional shear components are expected above that within the buoyancy layer. Maturing cells will attempt to form supercell structures, but given the nearly parallel orientation of the front with respect to the deep-layer westerly flow regime, convective mode should favor west/east-oriented clusters. These should largely progress south-southeast amid the undercutting nature of the composite front and emerging convective outflows. Due to the initially steep mid-level lapse rates and enlarged low-level hodographs, there is concern for a brief supercell tornado and isolated hail threat. Though with the limiting factors, it appears damaging winds should be the primary hazard during the evening before convection wanes with southern extent overnight. ..Grams.. 04/13/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1240 AM CDT Sat Apr 13 2024 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF PA TO EAST OH... ...SUMMARY... Isolated to scattered severe thunderstorms are possible from late afternoon into the evening on Sunday, across eastern Indiana into the Northeast States. Damaging winds should be the primary hazard, but a tornado or two and large hail are also possible. ...Northeast States to eastern IN... A mid-level jetlet attendant to a low-amplitude shortwave impulse should progress across the northern Great Lakes and Ontario into New England by Sunday evening. Weak cyclogenesis should occur with the surface low tracking east across parts of NY. An attendant cold front should arc westward and progress southeastward. A pronounced elevated mixed layer across the Midwest and southern Great Lakes will shift southeastward into the Mid-Atlantic and Southeast States. This elevated mixed layer will likely cap surface-based convection until near/after peak heating along the west/east-oriented cold front. 00Z RRFS/NAM soundings appear relatively reasonable with this evolution as modified low-level moisture return emanating from the southern Great Plains struggles to reduce MLCIN until cooling aloft advects in from the west-northwest. Other guidance may be too moist within the boundary layer given upstream observations and 36 hours of air mass modification remaining. Still, a corridor of MLCAPE reaching 1000-1500 J/kg will probably develop in IN/OH given the initially steep mid-level lapse rates. This buoyancy plume will subside with eastern extent towards the DE Valley. Hodographs across the region should be dominated by low-level curvature enlargement, especially with eastern extent. However, weak speed and directional shear components are expected above that within the buoyancy layer. Maturing cells will attempt to form supercell structures, but given the nearly parallel orientation of the front with respect to the deep-layer westerly flow regime, convective mode should favor west/east-oriented clusters. These should largely progress south-southeast amid the undercutting nature of the composite front and emerging convective outflows. Due to the initially steep mid-level lapse rates and enlarged low-level hodographs, there is concern for a brief supercell tornado and isolated hail threat. Though with the limiting factors, it appears damaging winds should be the primary hazard during the evening before convection wanes with southern extent overnight. ..Grams.. 04/13/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1240 AM CDT Sat Apr 13 2024 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF PA TO EAST OH... ...SUMMARY... Isolated to scattered severe thunderstorms are possible from late afternoon into the evening on Sunday, across eastern Indiana into the Northeast States. Damaging winds should be the primary hazard, but a tornado or two and large hail are also possible. ...Northeast States to eastern IN... A mid-level jetlet attendant to a low-amplitude shortwave impulse should progress across the northern Great Lakes and Ontario into New England by Sunday evening. Weak cyclogenesis should occur with the surface low tracking east across parts of NY. An attendant cold front should arc westward and progress southeastward. A pronounced elevated mixed layer across the Midwest and southern Great Lakes will shift southeastward into the Mid-Atlantic and Southeast States. This elevated mixed layer will likely cap surface-based convection until near/after peak heating along the west/east-oriented cold front. 00Z RRFS/NAM soundings appear relatively reasonable with this evolution as modified low-level moisture return emanating from the southern Great Plains struggles to reduce MLCIN until cooling aloft advects in from the west-northwest. Other guidance may be too moist within the boundary layer given upstream observations and 36 hours of air mass modification remaining. Still, a corridor of MLCAPE reaching 1000-1500 J/kg will probably develop in IN/OH given the initially steep mid-level lapse rates. This buoyancy plume will subside with eastern extent towards the DE Valley. Hodographs across the region should be dominated by low-level curvature enlargement, especially with eastern extent. However, weak speed and directional shear components are expected above that within the buoyancy layer. Maturing cells will attempt to form supercell structures, but given the nearly parallel orientation of the front with respect to the deep-layer westerly flow regime, convective mode should favor west/east-oriented clusters. These should largely progress south-southeast amid the undercutting nature of the composite front and emerging convective outflows. Due to the initially steep mid-level lapse rates and enlarged low-level hodographs, there is concern for a brief supercell tornado and isolated hail threat. Though with the limiting factors, it appears damaging winds should be the primary hazard during the evening before convection wanes with southern extent overnight. ..Grams.. 04/13/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1249 AM CDT Sat Apr 13 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF OREGON... ...SUMMARY... Thunderstorm associated with strong wind gusts and hail will be possible this afternoon and early this evening across parts of central Oregon. ...Central Oregon... An upper-level low will remain just offshore from the northern California coast today. To the east of the system, a diffluent upper-level pattern will be present from the Intermountain West into the Pacific Northwest. As surface heating takes place across the Pacific Northwest today, a pocket of weak instability will develop across Oregon, where MLCAPE is forecast to peak in the 500 to 1000 J/kg range. To the northeast of the upper-level low, large-scale ascent will aid scattered thunderstorm development. The instability, along with moderate deep-layer shear and steep mid-level lapse rates, will likely support a marginal severe threat. The stronger rotating cells could be associated with hail and isolated damaging gusts. ..Broyles.. 04/13/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1249 AM CDT Sat Apr 13 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF OREGON... ...SUMMARY... Thunderstorm associated with strong wind gusts and hail will be possible this afternoon and early this evening across parts of central Oregon. ...Central Oregon... An upper-level low will remain just offshore from the northern California coast today. To the east of the system, a diffluent upper-level pattern will be present from the Intermountain West into the Pacific Northwest. As surface heating takes place across the Pacific Northwest today, a pocket of weak instability will develop across Oregon, where MLCAPE is forecast to peak in the 500 to 1000 J/kg range. To the northeast of the upper-level low, large-scale ascent will aid scattered thunderstorm development. The instability, along with moderate deep-layer shear and steep mid-level lapse rates, will likely support a marginal severe threat. The stronger rotating cells could be associated with hail and isolated damaging gusts. ..Broyles.. 04/13/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1249 AM CDT Sat Apr 13 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF OREGON... ...SUMMARY... Thunderstorm associated with strong wind gusts and hail will be possible this afternoon and early this evening across parts of central Oregon. ...Central Oregon... An upper-level low will remain just offshore from the northern California coast today. To the east of the system, a diffluent upper-level pattern will be present from the Intermountain West into the Pacific Northwest. As surface heating takes place across the Pacific Northwest today, a pocket of weak instability will develop across Oregon, where MLCAPE is forecast to peak in the 500 to 1000 J/kg range. To the northeast of the upper-level low, large-scale ascent will aid scattered thunderstorm development. The instability, along with moderate deep-layer shear and steep mid-level lapse rates, will likely support a marginal severe threat. The stronger rotating cells could be associated with hail and isolated damaging gusts. ..Broyles.. 04/13/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1249 AM CDT Sat Apr 13 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF OREGON... ...SUMMARY... Thunderstorm associated with strong wind gusts and hail will be possible this afternoon and early this evening across parts of central Oregon. ...Central Oregon... An upper-level low will remain just offshore from the northern California coast today. To the east of the system, a diffluent upper-level pattern will be present from the Intermountain West into the Pacific Northwest. As surface heating takes place across the Pacific Northwest today, a pocket of weak instability will develop across Oregon, where MLCAPE is forecast to peak in the 500 to 1000 J/kg range. To the northeast of the upper-level low, large-scale ascent will aid scattered thunderstorm development. The instability, along with moderate deep-layer shear and steep mid-level lapse rates, will likely support a marginal severe threat. The stronger rotating cells could be associated with hail and isolated damaging gusts. ..Broyles.. 04/13/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1249 AM CDT Sat Apr 13 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF OREGON... ...SUMMARY... Thunderstorm associated with strong wind gusts and hail will be possible this afternoon and early this evening across parts of central Oregon. ...Central Oregon... An upper-level low will remain just offshore from the northern California coast today. To the east of the system, a diffluent upper-level pattern will be present from the Intermountain West into the Pacific Northwest. As surface heating takes place across the Pacific Northwest today, a pocket of weak instability will develop across Oregon, where MLCAPE is forecast to peak in the 500 to 1000 J/kg range. To the northeast of the upper-level low, large-scale ascent will aid scattered thunderstorm development. The instability, along with moderate deep-layer shear and steep mid-level lapse rates, will likely support a marginal severe threat. The stronger rotating cells could be associated with hail and isolated damaging gusts. ..Broyles.. 04/13/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1249 AM CDT Sat Apr 13 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF OREGON... ...SUMMARY... Thunderstorm associated with strong wind gusts and hail will be possible this afternoon and early this evening across parts of central Oregon. ...Central Oregon... An upper-level low will remain just offshore from the northern California coast today. To the east of the system, a diffluent upper-level pattern will be present from the Intermountain West into the Pacific Northwest. As surface heating takes place across the Pacific Northwest today, a pocket of weak instability will develop across Oregon, where MLCAPE is forecast to peak in the 500 to 1000 J/kg range. To the northeast of the upper-level low, large-scale ascent will aid scattered thunderstorm development. The instability, along with moderate deep-layer shear and steep mid-level lapse rates, will likely support a marginal severe threat. The stronger rotating cells could be associated with hail and isolated damaging gusts. ..Broyles.. 04/13/2024 Read more

Some drought stress was observed among the wheat crop in central Kansas.

MD 0433 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PARTS OF NORTHEASTERN OREGON INTO NORTH CENTRAL IDAHA
Mesoscale Discussion 0433 NWS Storm Prediction Center Norman OK 0736 PM CDT Fri Apr 12 2024 Areas affected...parts of northeastern Oregon into north central Idaha Concerning...Severe potential...Watch unlikely Valid 130036Z - 130230Z Probability of Watch Issuance...20 percent SUMMARY...A small cluster of thunderstorms may continue to evolve and organize near and east-northeast of the Baker OR vicinity, with increasing potential to produce strong to severe wind gusts while spreading toward the Bitterroot and Salmon River Mountains vicinity through 7-9 PM MDT. DISCUSSION...Thunderstorm development has recently intensified in a narrow line near/south of the Blue Mountains vicinity of northeastern Oregon. This appears aided by a focused area of large-scale ascent supported by low-level warm advection, beneath a difluent and divergent upper flow regime. As a high-level jet streak continues to propagate eastward to the north of the western Canadian/U.S. border vicinity, this forcing is forecast to generally shift east-northeastward into parts of the Salmon River Mountains and Bitterroot Range of north central Idaho. Although peak late afternoon instability appears characterized by relatively modest CAPE on the order of 500 J/kg, strong deep layer shear (50+ kt) may contribute further intensification of convection during the next few hours. The evolution of a small, but increasingly organized cluster of storms appears possible, which may gradually be accompanied by strengthening rear inflow and perhaps increasing potential for strong to severe gusts to reach the surface, aided by relatively dry sub-cloud air with modestly steep lapse rates. ..Kerr/Thompson.. 04/13/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MSO...BOI...PDT... LAT...LON 44841815 46031625 46041454 45081549 44021738 43971789 44521796 44841815 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0753 PM CDT Fri Apr 12 2024 Valid 130100Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE PACIFIC NORTHWEST AND FAR EASTERN NORTH CAROLINA... ...SUMMARY... Isolated severe wind gusts and hail may occur with thunderstorms from eastern Oregon to western Montana this evening. A few strong wind gusts may also occur in far eastern North Carolina. ...Pacific Northwest/Northern Rockies... The latest water vapor imagery shows an anticyclonic flow pattern over much of the western and central U.S. A shortwave trough is appears to be moving through the Pacific Northwest. Scattered thunderstorms are ongoing ahead of the shortwave from eastern Oregon into southern Idaho. These storms will move northeastward across the Pacific Northwest and into the northern Rockies this evening. The RAP shows a pocket of maximized instability across central and northern Idaho, where MLCAPE is estimated to be near 500 J/kg. Within this area, moderate deep-layer shear is also analyzed, with 700-500 mb lapse rates in the 8.5 to 9.5 C/km range. This environment should support an isolated wind-damage and hail threat this evening. ...Far Eastern North Carolina... An upper-level trough, evident on water vapor imagery, is currently moving through the Carolinas. Ahead of the trough, a pocket of weak instability is located near the coast of North Carolina, where a line of thunderstorms is currently ongoing. This line will move eastward across the Cape Hatteras over the next hour, where isolated strong to severe wind gusts will be possible. The threat is expected to move offshore after 02z. ..Broyles.. 04/13/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0753 PM CDT Fri Apr 12 2024 Valid 130100Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE PACIFIC NORTHWEST AND FAR EASTERN NORTH CAROLINA... ...SUMMARY... Isolated severe wind gusts and hail may occur with thunderstorms from eastern Oregon to western Montana this evening. A few strong wind gusts may also occur in far eastern North Carolina. ...Pacific Northwest/Northern Rockies... The latest water vapor imagery shows an anticyclonic flow pattern over much of the western and central U.S. A shortwave trough is appears to be moving through the Pacific Northwest. Scattered thunderstorms are ongoing ahead of the shortwave from eastern Oregon into southern Idaho. These storms will move northeastward across the Pacific Northwest and into the northern Rockies this evening. The RAP shows a pocket of maximized instability across central and northern Idaho, where MLCAPE is estimated to be near 500 J/kg. Within this area, moderate deep-layer shear is also analyzed, with 700-500 mb lapse rates in the 8.5 to 9.5 C/km range. This environment should support an isolated wind-damage and hail threat this evening. ...Far Eastern North Carolina... An upper-level trough, evident on water vapor imagery, is currently moving through the Carolinas. Ahead of the trough, a pocket of weak instability is located near the coast of North Carolina, where a line of thunderstorms is currently ongoing. This line will move eastward across the Cape Hatteras over the next hour, where isolated strong to severe wind gusts will be possible. The threat is expected to move offshore after 02z. ..Broyles.. 04/13/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0753 PM CDT Fri Apr 12 2024 Valid 130100Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE PACIFIC NORTHWEST AND FAR EASTERN NORTH CAROLINA... ...SUMMARY... Isolated severe wind gusts and hail may occur with thunderstorms from eastern Oregon to western Montana this evening. A few strong wind gusts may also occur in far eastern North Carolina. ...Pacific Northwest/Northern Rockies... The latest water vapor imagery shows an anticyclonic flow pattern over much of the western and central U.S. A shortwave trough is appears to be moving through the Pacific Northwest. Scattered thunderstorms are ongoing ahead of the shortwave from eastern Oregon into southern Idaho. These storms will move northeastward across the Pacific Northwest and into the northern Rockies this evening. The RAP shows a pocket of maximized instability across central and northern Idaho, where MLCAPE is estimated to be near 500 J/kg. Within this area, moderate deep-layer shear is also analyzed, with 700-500 mb lapse rates in the 8.5 to 9.5 C/km range. This environment should support an isolated wind-damage and hail threat this evening. ...Far Eastern North Carolina... An upper-level trough, evident on water vapor imagery, is currently moving through the Carolinas. Ahead of the trough, a pocket of weak instability is located near the coast of North Carolina, where a line of thunderstorms is currently ongoing. This line will move eastward across the Cape Hatteras over the next hour, where isolated strong to severe wind gusts will be possible. The threat is expected to move offshore after 02z. ..Broyles.. 04/13/2024 Read more

MD 0432 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTHEAST NORTH CAROLINA
Mesoscale Discussion 0432 NWS Storm Prediction Center Norman OK 0556 PM CDT Fri Apr 12 2024 Areas affected...Southeast North Carolina Concerning...Severe potential...Watch unlikely Valid 122256Z - 130100Z Probability of Watch Issuance...5 percent SUMMARY...Weak convection will pose a damaging wind risk over the next 1-2 hours as storms approach the southeastern North Carolina coast. Watch issuance is not expected. DISCUSSION...Weak, shallow convection migrating eastward across southern NC has persisted over the past 1-2 hours despite a very marginal thermodynamic environment (MLCAPE generally near 250 J/kg or less per recent mesoanalyses and forecast soundings). This persistence is likely attributable to lift ahead of a subtle vorticity maximum. Despite the poor buoyancy, low-level warming has resulted in steep boundary-layer lapse rates up to 7-8 C/km, which is facilitating downward transfer of stronger mid-level flow. Surface observations have reported isolated severe winds (59 mph was recently measured at KFAY), with more frequent gusts around 35-50 mph. While severe winds will likely be confined to very narrow swaths, the relatively more widespread 35-50 mph winds will pose a wind damage risk. The onset of nocturnal cooling in the coming hours will further limit convective intensity and should hinder efficient mixing, but favorable forcing for ascent may maintain poorly organized convection (and associated damaging wind threat) to the NC coast. ..Moore/Thompson.. 04/12/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MHX...RAH...ILM... LAT...LON 34377914 34667927 34977919 35247862 35497776 35557718 35517645 35307620 35117641 34847676 34567724 34347762 34147791 34107814 34287895 34377914 Read more

No watches are valid as of Fri Apr 12 23:46:02 UTC 2024.

MD 0432 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTHEAST NORTH CAROLINA
Mesoscale Discussion 0432 NWS Storm Prediction Center Norman OK 0556 PM CDT Fri Apr 12 2024 Areas affected...Southeast North Carolina Concerning...Severe potential...Watch unlikely Valid 122256Z - 130100Z Probability of Watch Issuance...5 percent SUMMARY...Weak convection will pose a damaging wind risk over the next 1-2 hours as storms approach the southeastern North Carolina coast. Watch issuance is not expected. DISCUSSION...Weak, shallow convection migrating eastward across southern NC has persisted over the past 1-2 hours despite a very marginal thermodynamic environment (MLCAPE generally near 250 J/kg or less per recent mesoanalyses and forecast soundings). This persistence is likely attributable to lift ahead of a subtle vorticity maximum. Despite the poor buoyancy, low-level warming has resulted in steep boundary-layer lapse rates up to 7-8 C/km, which is facilitating downward transfer of stronger mid-level flow. Surface observations have reported isolated severe winds (59 mph was recently measured at KFAY), with more frequent gusts around 35-50 mph. While severe winds will likely be confined to very narrow swaths, the relatively more widespread 35-50 mph winds will pose a wind damage risk. The onset of nocturnal cooling in the coming hours will further limit convective intensity and should hinder efficient mixing, but favorable forcing for ascent may maintain poorly organized convection (and associated damaging wind threat) to the NC coast. ..Moore/Thompson.. 04/12/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MHX...RAH...ILM... LAT...LON 34377914 34667927 34977919 35247862 35497776 35557718 35517645 35307620 35117641 34847676 34567724 34347762 34147791 34107814 34287895 34377914 Read more

MD 0431 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR IDAHO INTO FAR SOUTHWEST MONTANA
Mesoscale Discussion 0431 NWS Storm Prediction Center Norman OK 0442 PM CDT Fri Apr 12 2024 Areas affected...Idaho into far southwest Montana Concerning...Severe potential...Watch unlikely Valid 122142Z - 122345Z Probability of Watch Issuance...5 percent SUMMARY...Developing thunderstorms across southern Idaho are expected to pose a severe wind and hail risk through the late afternoon hours as they spread northeast into central Idaho and far southwest Montana. Watch issuance is unlikely given the localized nature of the threat and somewhat marginal environment. DISCUSSION...Latest GOES visible and IR imagery show a cluster of steadily deepening cumulus across south-central ID. This is likely in response to a combination of quickly eroding MLCIN and increasing ascent ahead of a mid-level wave approaching from the south/southwest. Deep boundary-layer mixing is limiting buoyancy with MLCAPE values generally between 250-500 J/kg; however, this has resulted in 0-3 km lapse rates between 8-9 C/km, which will support the potential for strong to severe downburst winds with deeper convective cells. This potential will likely be maximized across areas where temperatures have warmed into the mid/upper 70s. 30-40 knot mid-level winds are elongating mid-level hodographs enough to support effective bulk shear values around 30-35 knots. This kinematic environment, combined with steep mid-level lapse rates, may allow for a supercell or two that will pose a severe hail risk (though this scenario is less certain given the modest buoyancy). The marginal nature of the buoyancy field and weak/nebulous forcing for ascent should limit the overall extent of the severe threat as storms spread north/northeast. ..Moore/Thompson.. 04/12/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...TFX...PIH...MSO...BOI... LAT...LON 42091474 42131568 42301679 42471699 42911693 45631503 45711423 45631372 45271304 44931268 44571244 44261232 43851245 42141432 42091474 Read more

No Mesoscale Discussions are in effect as of Fri Apr 12 20:35:02 UTC 2024.