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SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1224 AM CDT Tue Jul 23 2024 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTHERN OHIO AND PENNSYLVANIA INTO NEW YORK... ...SUMMARY... Isolated strong to severe thunderstorms may produce damaging gusts across parts of northern Ohio and Pennsylvania into New York Wednesday afternoon and evening. ...Synopsis... An upper shortwave trough over the upper Great Lakes will develop eastward toward the upper Ohio Valley/lower Great Lakes vicinity on Wednesday. At the same time, the sub-tropical high over the western Atlantic will scoot westward toward the Mid-Atlantic and Southeast. This will result in an increasing/tightening height gradient across the Northeast as the upper trough develops east, and southwesterly mid/upper flow will increase from the Ohio Valley into the Mid-Atlantic and Northeast. Further west, an upper shortwave trough will develop east/southeast over the Pacific Northwest and northern Rockies, while an upper anticyclone persists over the Southwest. As the Pacific Northwest trough moves east, an upper ridge will overspread the central Rockies to the northern Plains. At the surface, a weak low will track northeast from the Lake Huron vicinity into southern Quebec. A trailing cold front will sag south/southeast across northern IL/IN/OH/PA and western NY during the afternoon and into the overnight hours. Meanwhile, a surface trough will extend southwest across the Chesapeake Bay vicinity into central NC. A moist airmass will be in place ahead of the surface cold front and near the surface trough, aiding in at least weak to moderate destabilization. These boundaries also will focus thunderstorm potential during the afternoon and evening hours. Further west, a baroclinic zone will exist over the northern Plains as a surface low deepens over the Canadian Prairies and high pressure builds over the upper Great Lakes. South/southeasterly low-level flow will allow for 60s F dewpoints across central/eastern portions of the Dakotas. However, capping within the amplifying upper ridge will likely preclude thunderstorm development. ...Northern OH/PA into NY... Increasing mid/upper-level southwesterly flow will support around 30-35 kt effective shear magnitudes by afternoon. Midlevel lapse rates will remain modest, but heating into the 80s and dewpoints in the mid/upper 60s F will allow for MLCAPE as high as 1500 J/kg. Stronger height falls will likely not occur until around/after 00z, somewhat misaligned with peak heating. Nevertheless, increasing vertical shear and modest large-scale ascent, coupled with the approaching cold front should support at least isolated to scattered thunderstorm development during the afternoon. Elongated hodographs and modest vertically veering wind profiles suggest organized cells, with perhaps transient supercell characteristics, will be possible. Steepening low-level lapse rates will support sporadic strong/locally damaging gusts. A couple of the strongest cells may produce marginal hail. ...Southeast VA into central/eastern NC... Thunderstorms are expected to develop within a very moist and unstable airmass Wednesday afternoon. While midlevel flow will gradually increase, vertical shear will remain marginal for organized convection, especially until after 00z. Given the high PW/moderately unstable airmass, a wet microburst or two will be possible. However, modest vertical shear and poor midlevel lapse rates preclude severe probabilities at this time. ..Leitman.. 07/23/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1224 AM CDT Tue Jul 23 2024 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTHERN OHIO AND PENNSYLVANIA INTO NEW YORK... ...SUMMARY... Isolated strong to severe thunderstorms may produce damaging gusts across parts of northern Ohio and Pennsylvania into New York Wednesday afternoon and evening. ...Synopsis... An upper shortwave trough over the upper Great Lakes will develop eastward toward the upper Ohio Valley/lower Great Lakes vicinity on Wednesday. At the same time, the sub-tropical high over the western Atlantic will scoot westward toward the Mid-Atlantic and Southeast. This will result in an increasing/tightening height gradient across the Northeast as the upper trough develops east, and southwesterly mid/upper flow will increase from the Ohio Valley into the Mid-Atlantic and Northeast. Further west, an upper shortwave trough will develop east/southeast over the Pacific Northwest and northern Rockies, while an upper anticyclone persists over the Southwest. As the Pacific Northwest trough moves east, an upper ridge will overspread the central Rockies to the northern Plains. At the surface, a weak low will track northeast from the Lake Huron vicinity into southern Quebec. A trailing cold front will sag south/southeast across northern IL/IN/OH/PA and western NY during the afternoon and into the overnight hours. Meanwhile, a surface trough will extend southwest across the Chesapeake Bay vicinity into central NC. A moist airmass will be in place ahead of the surface cold front and near the surface trough, aiding in at least weak to moderate destabilization. These boundaries also will focus thunderstorm potential during the afternoon and evening hours. Further west, a baroclinic zone will exist over the northern Plains as a surface low deepens over the Canadian Prairies and high pressure builds over the upper Great Lakes. South/southeasterly low-level flow will allow for 60s F dewpoints across central/eastern portions of the Dakotas. However, capping within the amplifying upper ridge will likely preclude thunderstorm development. ...Northern OH/PA into NY... Increasing mid/upper-level southwesterly flow will support around 30-35 kt effective shear magnitudes by afternoon. Midlevel lapse rates will remain modest, but heating into the 80s and dewpoints in the mid/upper 60s F will allow for MLCAPE as high as 1500 J/kg. Stronger height falls will likely not occur until around/after 00z, somewhat misaligned with peak heating. Nevertheless, increasing vertical shear and modest large-scale ascent, coupled with the approaching cold front should support at least isolated to scattered thunderstorm development during the afternoon. Elongated hodographs and modest vertically veering wind profiles suggest organized cells, with perhaps transient supercell characteristics, will be possible. Steepening low-level lapse rates will support sporadic strong/locally damaging gusts. A couple of the strongest cells may produce marginal hail. ...Southeast VA into central/eastern NC... Thunderstorms are expected to develop within a very moist and unstable airmass Wednesday afternoon. While midlevel flow will gradually increase, vertical shear will remain marginal for organized convection, especially until after 00z. Given the high PW/moderately unstable airmass, a wet microburst or two will be possible. However, modest vertical shear and poor midlevel lapse rates preclude severe probabilities at this time. ..Leitman.. 07/23/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1224 AM CDT Tue Jul 23 2024 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTHERN OHIO AND PENNSYLVANIA INTO NEW YORK... ...SUMMARY... Isolated strong to severe thunderstorms may produce damaging gusts across parts of northern Ohio and Pennsylvania into New York Wednesday afternoon and evening. ...Synopsis... An upper shortwave trough over the upper Great Lakes will develop eastward toward the upper Ohio Valley/lower Great Lakes vicinity on Wednesday. At the same time, the sub-tropical high over the western Atlantic will scoot westward toward the Mid-Atlantic and Southeast. This will result in an increasing/tightening height gradient across the Northeast as the upper trough develops east, and southwesterly mid/upper flow will increase from the Ohio Valley into the Mid-Atlantic and Northeast. Further west, an upper shortwave trough will develop east/southeast over the Pacific Northwest and northern Rockies, while an upper anticyclone persists over the Southwest. As the Pacific Northwest trough moves east, an upper ridge will overspread the central Rockies to the northern Plains. At the surface, a weak low will track northeast from the Lake Huron vicinity into southern Quebec. A trailing cold front will sag south/southeast across northern IL/IN/OH/PA and western NY during the afternoon and into the overnight hours. Meanwhile, a surface trough will extend southwest across the Chesapeake Bay vicinity into central NC. A moist airmass will be in place ahead of the surface cold front and near the surface trough, aiding in at least weak to moderate destabilization. These boundaries also will focus thunderstorm potential during the afternoon and evening hours. Further west, a baroclinic zone will exist over the northern Plains as a surface low deepens over the Canadian Prairies and high pressure builds over the upper Great Lakes. South/southeasterly low-level flow will allow for 60s F dewpoints across central/eastern portions of the Dakotas. However, capping within the amplifying upper ridge will likely preclude thunderstorm development. ...Northern OH/PA into NY... Increasing mid/upper-level southwesterly flow will support around 30-35 kt effective shear magnitudes by afternoon. Midlevel lapse rates will remain modest, but heating into the 80s and dewpoints in the mid/upper 60s F will allow for MLCAPE as high as 1500 J/kg. Stronger height falls will likely not occur until around/after 00z, somewhat misaligned with peak heating. Nevertheless, increasing vertical shear and modest large-scale ascent, coupled with the approaching cold front should support at least isolated to scattered thunderstorm development during the afternoon. Elongated hodographs and modest vertically veering wind profiles suggest organized cells, with perhaps transient supercell characteristics, will be possible. Steepening low-level lapse rates will support sporadic strong/locally damaging gusts. A couple of the strongest cells may produce marginal hail. ...Southeast VA into central/eastern NC... Thunderstorms are expected to develop within a very moist and unstable airmass Wednesday afternoon. While midlevel flow will gradually increase, vertical shear will remain marginal for organized convection, especially until after 00z. Given the high PW/moderately unstable airmass, a wet microburst or two will be possible. However, modest vertical shear and poor midlevel lapse rates preclude severe probabilities at this time. ..Leitman.. 07/23/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Tue Jul 23 2024 Valid 231200Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for organized severe thunderstorms appears low on Tuesday. ...Synopsis... The large-scale upper-level pattern will change little on Tuesday, with a pronounced anticyclone over much of the West, and a trough from the Great Lakes northeast into eastern Canada. A weak surface front will extend from near the Delmarva Peninsula southwest into central TX, and serve as a focus for more concentrated showers and thunderstorms. Farther north, another weak/slow-moving front will extend from the Great Lakes into the Dakotas. Although no severe probabilities are introduced with this outlook, some localized severe potential is possible, and highlighted below. ...Mid-Atlantic/southeast... The air mass over much of the southeast and mid-Atlantic states near and south of the front Tuesday will remain very moist with PW values in excess of 2 inches, contributing to moderate MLCAPE by afternoon. Although a modest increase in mid-level flow is forecast from the southern Appalachians northeast across the mid-Atlantic, low-level flow will remain weak. Additionally, the lack of a well-defined impulse embedded within the mid-level flow suggests that any severe risk, likely in the form of strong/damaging gusts, should remain localized in nature. ...Midwest... Thunderstorms are expected to redevelop along the northern front from southern WI across IA and southern MN Tuesday afternoon, with the potential for multiple rounds of storms in some locations. Moderate buoyancy should be in place near the front, however deep-layer shear should generally remain at or below 25 kts for much of the day. Some risk for hail and gusty winds will exist with any stronger storm, but overall confidence in introducing a severe risk area remains low. ...Arizona/Lower Colorado River Valley... Thunderstorms are expected to develop over the Mogollon Rim of Arizona again Tuesday, with relatively weak northeast mid-level flow steering storms southwest into the lower elevations. Despite very hot temperatures and a deep/well-mixed boundary layer, overall confidence that storms will cluster and produce more than localized strong/damaging gusts is too low to introduce a severe risk area. ..Bunting/Lyons.. 07/23/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Tue Jul 23 2024 Valid 231200Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for organized severe thunderstorms appears low on Tuesday. ...Synopsis... The large-scale upper-level pattern will change little on Tuesday, with a pronounced anticyclone over much of the West, and a trough from the Great Lakes northeast into eastern Canada. A weak surface front will extend from near the Delmarva Peninsula southwest into central TX, and serve as a focus for more concentrated showers and thunderstorms. Farther north, another weak/slow-moving front will extend from the Great Lakes into the Dakotas. Although no severe probabilities are introduced with this outlook, some localized severe potential is possible, and highlighted below. ...Mid-Atlantic/southeast... The air mass over much of the southeast and mid-Atlantic states near and south of the front Tuesday will remain very moist with PW values in excess of 2 inches, contributing to moderate MLCAPE by afternoon. Although a modest increase in mid-level flow is forecast from the southern Appalachians northeast across the mid-Atlantic, low-level flow will remain weak. Additionally, the lack of a well-defined impulse embedded within the mid-level flow suggests that any severe risk, likely in the form of strong/damaging gusts, should remain localized in nature. ...Midwest... Thunderstorms are expected to redevelop along the northern front from southern WI across IA and southern MN Tuesday afternoon, with the potential for multiple rounds of storms in some locations. Moderate buoyancy should be in place near the front, however deep-layer shear should generally remain at or below 25 kts for much of the day. Some risk for hail and gusty winds will exist with any stronger storm, but overall confidence in introducing a severe risk area remains low. ...Arizona/Lower Colorado River Valley... Thunderstorms are expected to develop over the Mogollon Rim of Arizona again Tuesday, with relatively weak northeast mid-level flow steering storms southwest into the lower elevations. Despite very hot temperatures and a deep/well-mixed boundary layer, overall confidence that storms will cluster and produce more than localized strong/damaging gusts is too low to introduce a severe risk area. ..Bunting/Lyons.. 07/23/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Tue Jul 23 2024 Valid 231200Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for organized severe thunderstorms appears low on Tuesday. ...Synopsis... The large-scale upper-level pattern will change little on Tuesday, with a pronounced anticyclone over much of the West, and a trough from the Great Lakes northeast into eastern Canada. A weak surface front will extend from near the Delmarva Peninsula southwest into central TX, and serve as a focus for more concentrated showers and thunderstorms. Farther north, another weak/slow-moving front will extend from the Great Lakes into the Dakotas. Although no severe probabilities are introduced with this outlook, some localized severe potential is possible, and highlighted below. ...Mid-Atlantic/southeast... The air mass over much of the southeast and mid-Atlantic states near and south of the front Tuesday will remain very moist with PW values in excess of 2 inches, contributing to moderate MLCAPE by afternoon. Although a modest increase in mid-level flow is forecast from the southern Appalachians northeast across the mid-Atlantic, low-level flow will remain weak. Additionally, the lack of a well-defined impulse embedded within the mid-level flow suggests that any severe risk, likely in the form of strong/damaging gusts, should remain localized in nature. ...Midwest... Thunderstorms are expected to redevelop along the northern front from southern WI across IA and southern MN Tuesday afternoon, with the potential for multiple rounds of storms in some locations. Moderate buoyancy should be in place near the front, however deep-layer shear should generally remain at or below 25 kts for much of the day. Some risk for hail and gusty winds will exist with any stronger storm, but overall confidence in introducing a severe risk area remains low. ...Arizona/Lower Colorado River Valley... Thunderstorms are expected to develop over the Mogollon Rim of Arizona again Tuesday, with relatively weak northeast mid-level flow steering storms southwest into the lower elevations. Despite very hot temperatures and a deep/well-mixed boundary layer, overall confidence that storms will cluster and produce more than localized strong/damaging gusts is too low to introduce a severe risk area. ..Bunting/Lyons.. 07/23/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Tue Jul 23 2024 Valid 231200Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for organized severe thunderstorms appears low on Tuesday. ...Synopsis... The large-scale upper-level pattern will change little on Tuesday, with a pronounced anticyclone over much of the West, and a trough from the Great Lakes northeast into eastern Canada. A weak surface front will extend from near the Delmarva Peninsula southwest into central TX, and serve as a focus for more concentrated showers and thunderstorms. Farther north, another weak/slow-moving front will extend from the Great Lakes into the Dakotas. Although no severe probabilities are introduced with this outlook, some localized severe potential is possible, and highlighted below. ...Mid-Atlantic/southeast... The air mass over much of the southeast and mid-Atlantic states near and south of the front Tuesday will remain very moist with PW values in excess of 2 inches, contributing to moderate MLCAPE by afternoon. Although a modest increase in mid-level flow is forecast from the southern Appalachians northeast across the mid-Atlantic, low-level flow will remain weak. Additionally, the lack of a well-defined impulse embedded within the mid-level flow suggests that any severe risk, likely in the form of strong/damaging gusts, should remain localized in nature. ...Midwest... Thunderstorms are expected to redevelop along the northern front from southern WI across IA and southern MN Tuesday afternoon, with the potential for multiple rounds of storms in some locations. Moderate buoyancy should be in place near the front, however deep-layer shear should generally remain at or below 25 kts for much of the day. Some risk for hail and gusty winds will exist with any stronger storm, but overall confidence in introducing a severe risk area remains low. ...Arizona/Lower Colorado River Valley... Thunderstorms are expected to develop over the Mogollon Rim of Arizona again Tuesday, with relatively weak northeast mid-level flow steering storms southwest into the lower elevations. Despite very hot temperatures and a deep/well-mixed boundary layer, overall confidence that storms will cluster and produce more than localized strong/damaging gusts is too low to introduce a severe risk area. ..Bunting/Lyons.. 07/23/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Tue Jul 23 2024 Valid 231200Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for organized severe thunderstorms appears low on Tuesday. ...Synopsis... The large-scale upper-level pattern will change little on Tuesday, with a pronounced anticyclone over much of the West, and a trough from the Great Lakes northeast into eastern Canada. A weak surface front will extend from near the Delmarva Peninsula southwest into central TX, and serve as a focus for more concentrated showers and thunderstorms. Farther north, another weak/slow-moving front will extend from the Great Lakes into the Dakotas. Although no severe probabilities are introduced with this outlook, some localized severe potential is possible, and highlighted below. ...Mid-Atlantic/southeast... The air mass over much of the southeast and mid-Atlantic states near and south of the front Tuesday will remain very moist with PW values in excess of 2 inches, contributing to moderate MLCAPE by afternoon. Although a modest increase in mid-level flow is forecast from the southern Appalachians northeast across the mid-Atlantic, low-level flow will remain weak. Additionally, the lack of a well-defined impulse embedded within the mid-level flow suggests that any severe risk, likely in the form of strong/damaging gusts, should remain localized in nature. ...Midwest... Thunderstorms are expected to redevelop along the northern front from southern WI across IA and southern MN Tuesday afternoon, with the potential for multiple rounds of storms in some locations. Moderate buoyancy should be in place near the front, however deep-layer shear should generally remain at or below 25 kts for much of the day. Some risk for hail and gusty winds will exist with any stronger storm, but overall confidence in introducing a severe risk area remains low. ...Arizona/Lower Colorado River Valley... Thunderstorms are expected to develop over the Mogollon Rim of Arizona again Tuesday, with relatively weak northeast mid-level flow steering storms southwest into the lower elevations. Despite very hot temperatures and a deep/well-mixed boundary layer, overall confidence that storms will cluster and produce more than localized strong/damaging gusts is too low to introduce a severe risk area. ..Bunting/Lyons.. 07/23/2024 Read more

000
ABPZ20 KNHC 230502
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM PDT Mon Jul 22 2024

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

Central and Western East Pacific:
A tropical wave located several hundred miles south-southwest of the
southern tip of the Baja California Peninsula is producing
disorganized shower and thunderstorm activity. Environmental
conditions could become a little more conducive for some gradual
development of this system over the next several days while it moves
westward to west-northwestward at 10 to 15 mph across the central
and western portions of the basin.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 7 days...low...30 percent.

Offshore Southwestern Mexico:
An area of showers and thunderstorms located a few hundred miles
south of Manzanillo, Mexico is associated with a tropical wave.
Some development of this system is possible while it moves
generally west-northwestward over the next couple of days, remaining
offshore of southwestern Mexico.
* Formation chance through 48 hours...low...30 percent.
* Formation chance through 7 days...low...30 percent.

$$
Forecaster Pasch

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0801 PM CDT Mon Jul 22 2024 Valid 230100Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER SOUTHERN AND EASTERN NORTH CAROLINA...CENTRAL AND EASTERN NORTH DAKOTA...AND WESTERN ARIZONA... ...SUMMARY... Isolated severe thunderstorms remain possible early this evening over portions of North Dakota, southern and eastern North Carolina, as well as western Arizona to the lower Colorado River Valley. ...North Dakota... A small cluster of strong/severe thunderstorms continued moving south across eastern ND at 01z, with a history of severe hail and wind gusts. A weak mid-level impulse continues to provide subtle large-scale ascent as it moves southeast near the international border, and the downstream environment will remain strongly unstable for the next few hours. With around 30 kts of deep-layer shear, sufficient storm organization is expected to persist for a continued severe threat through the remainder of this evening. ...Western Arizona and Vicinity... Scattered thunderstorms continue moving generally south within a weakly buoyant environment with a well-mixed boundary layer (LCL heights over 3500 meters). Storms have not shown a tendency to cluster thus far, however any merging outflows that can develop will have severe wind potential through this evening. ...Mid-Atlantic... Have trimmed the Marginal Risk and associated wind/tornado probabilities to in the immediate vicinity of the storms extending from near Elizabeth City (KECG) to Clinton NC (KCTZ). Latest mesoanalysis shows moderate bouyancy and 30-40 kts of shear in the near-storm environment. Occasional weak/transient cyclonic shear has been noted in a couple of these storms, and effective SRH of 100 m2/s2 would support some continued (though low probability) risk for a brief tornado or gusty winds this evening. ..Bunting.. 07/23/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0801 PM CDT Mon Jul 22 2024 Valid 230100Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER SOUTHERN AND EASTERN NORTH CAROLINA...CENTRAL AND EASTERN NORTH DAKOTA...AND WESTERN ARIZONA... ...SUMMARY... Isolated severe thunderstorms remain possible early this evening over portions of North Dakota, southern and eastern North Carolina, as well as western Arizona to the lower Colorado River Valley. ...North Dakota... A small cluster of strong/severe thunderstorms continued moving south across eastern ND at 01z, with a history of severe hail and wind gusts. A weak mid-level impulse continues to provide subtle large-scale ascent as it moves southeast near the international border, and the downstream environment will remain strongly unstable for the next few hours. With around 30 kts of deep-layer shear, sufficient storm organization is expected to persist for a continued severe threat through the remainder of this evening. ...Western Arizona and Vicinity... Scattered thunderstorms continue moving generally south within a weakly buoyant environment with a well-mixed boundary layer (LCL heights over 3500 meters). Storms have not shown a tendency to cluster thus far, however any merging outflows that can develop will have severe wind potential through this evening. ...Mid-Atlantic... Have trimmed the Marginal Risk and associated wind/tornado probabilities to in the immediate vicinity of the storms extending from near Elizabeth City (KECG) to Clinton NC (KCTZ). Latest mesoanalysis shows moderate bouyancy and 30-40 kts of shear in the near-storm environment. Occasional weak/transient cyclonic shear has been noted in a couple of these storms, and effective SRH of 100 m2/s2 would support some continued (though low probability) risk for a brief tornado or gusty winds this evening. ..Bunting.. 07/23/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0801 PM CDT Mon Jul 22 2024 Valid 230100Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER SOUTHERN AND EASTERN NORTH CAROLINA...CENTRAL AND EASTERN NORTH DAKOTA...AND WESTERN ARIZONA... ...SUMMARY... Isolated severe thunderstorms remain possible early this evening over portions of North Dakota, southern and eastern North Carolina, as well as western Arizona to the lower Colorado River Valley. ...North Dakota... A small cluster of strong/severe thunderstorms continued moving south across eastern ND at 01z, with a history of severe hail and wind gusts. A weak mid-level impulse continues to provide subtle large-scale ascent as it moves southeast near the international border, and the downstream environment will remain strongly unstable for the next few hours. With around 30 kts of deep-layer shear, sufficient storm organization is expected to persist for a continued severe threat through the remainder of this evening. ...Western Arizona and Vicinity... Scattered thunderstorms continue moving generally south within a weakly buoyant environment with a well-mixed boundary layer (LCL heights over 3500 meters). Storms have not shown a tendency to cluster thus far, however any merging outflows that can develop will have severe wind potential through this evening. ...Mid-Atlantic... Have trimmed the Marginal Risk and associated wind/tornado probabilities to in the immediate vicinity of the storms extending from near Elizabeth City (KECG) to Clinton NC (KCTZ). Latest mesoanalysis shows moderate bouyancy and 30-40 kts of shear in the near-storm environment. Occasional weak/transient cyclonic shear has been noted in a couple of these storms, and effective SRH of 100 m2/s2 would support some continued (though low probability) risk for a brief tornado or gusty winds this evening. ..Bunting.. 07/23/2024 Read more

000
ABPZ20 KNHC 222324
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 PM PDT Mon Jul 22 2024

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

Central and Western East Pacific:
A tropical wave located several hundred miles south-southwest of the
southern tip of the Baja California Peninsula is producing
disorganized shower and thunderstorm activity. Environmental
conditions could become a little more conducive for some gradual
development of this system over the next several days while it moves
westward to west-northwestward at 10 to 15 mph across the central
and western portions of the basin.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 7 days...low...30 percent.

Offshore Southwestern Mexico:
An area of showers and thunderstorms located a few hundred miles
south-southeast of Manzanillo, Mexico is associated with a tropical
wave. This system has become a little better organized today, and
some further development is possible while it moves generally
west-northwestward over the next couple of days, remaining offshore
of southwestern Mexico.
*Formation chance through 48 hours...low...20 percent.
*Formation chance through 7 days...low...20 percent.

$$
Forecaster Pasch

No watches are valid as of Mon Jul 22 23:01:02 UTC 2024.

No Mesoscale Discussions are in effect as of Mon Jul 22 23:01:02 UTC 2024.

MD 1695 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR NORTHEASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA.
Mesoscale Discussion 1695 NWS Storm Prediction Center Norman OK 0433 PM CDT Mon Jul 22 2024 Areas affected...northeastern North Dakota and northwest Minnesota. Concerning...Severe potential...Watch unlikely Valid 222133Z - 222300Z Probability of Watch Issuance...20 percent SUMMARY...Developing thunderstorm may remain capable of severe hail for a few hours this afternoon into the early evening. Confidence in storm evolution is low but a WW is not currently anticipated. DISCUSSION...As of 2120 UTC, regional radar imagery showed scattered thunderstorms have developed along a subtle confluence boundary stretching from near Minot ND to International Falls MN. Aided by weak forcing for ascent from a subtle passing shortwave trough, these storms have recently intensified with reports of measured severe hail. Warm surface temperatures and upper 60s to low 70s F dewpoints are supporting strong destabilization (3000+ J/kg of MLCAPE) despite only modest mid-level lapse rates. Vertical shear, as sampled by area VADs, is modestly favorable for a sustained severe risk around 25-30 kt. However, some mid and upper-level enhancement form the passing shortwave may allow for brief organization and transient supercell structures with the strongly buoyant updrafts. Given the degree of buoyancy and the potential for at least short-lived storm organization, the risk for severe hail (1-2 in) and an isolated damaging gust may persist for a couple hours late this afternoon into the early evening. Confidence in organized convective evolution is low as the background forcing away from the boundary remains limited. This suggests a WW is unlikely, but convective trends will continue to be monitored should a locally greater severe risk evolve. ..Lyons/Gleason.. 07/22/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FGF...BIS... LAT...LON 48229618 47789664 47609744 47599779 47609811 47659868 47809914 48079950 48439955 48809910 48969815 48939737 48839664 48829653 48499613 48229618 Read more

MD 1694 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF NORTHEASTERN NORTH CAROLINA AND FAR SOUTHEASTERN VIRGINIA
Mesoscale Discussion 1694 NWS Storm Prediction Center Norman OK 0349 PM CDT Mon Jul 22 2024 Areas affected...Portions of northeastern North Carolina and far southeastern Virginia Concerning...Severe potential...Watch unlikely Valid 222049Z - 222245Z Probability of Watch Issuance...20 percent SUMMARY...A localized damaging wind threat is increasing across portions of northeastern NC and far southeastern VA. A brief tornado also cannot be ruled out. DISCUSSION...Regional radar imagery shows a cluster of thunderstorms beginning to merge across northeastern NC. Additional thunderstorms were also developing along a differential heating boundary near the far eastern NC/VA border. These storms are an environment characterized by a moderately buoyant airmass and modest deep layer effective shear, under a belt of relatively stronger mid to upper level southwesterly flow. Continued cell mergers over the next 1-2 hours will have the opportunity to produce damaging wind gusts. In addition, slowly increasing low-level flow may result in a localized increase of helicity near the aforementioned boundary through early this evening, and thunderstorms exhibiting more supercell like structures may have the opportunity to produce a brief tornado before the onset of nocturnal stabilization. Given the very localized nature of the severe threat, however, a WW is not anticipated at this time. ..Barnes/Smith.. 07/22/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...AKQ...MHX...RAH... LAT...LON 37247578 37057582 36667583 36217580 35957610 35757710 35757774 35767836 35817868 36537821 36967772 37297746 37357674 37317619 37247578 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook AMEND 1 NWS Storm Prediction Center Norman OK 0502 PM CDT Mon Jul 22 2024 Valid 222155Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTH DAKOTA AND NORTHWEST MINNESOTA...THE DESERT SOUTHWEST...AND THE MID-ATLANTIC/EASTERN NORTH CAROLINA... AMENDED FOR ADDITION OF HAIL/WIND PROBABILITIES IN NORTH DAKOTA AND NORTHWEST MINNESOTA ...SUMMARY... Isolated severe thunderstorms remain possible this afternoon and early evening over portions of North Dakota and northwest Minnesota, the mid-Atlantic region, as well as western Arizona to the lower Colorado River Valley. ...North Dakota/Northwest Minnesota... Isolated strong to severe thunderstorms are ongoing along a weak boundary/low-level confluence axis across parts of northeast ND and northwest MN. A few instances of large hail have already occurred. The presence of moderate to locally strong instability, along with marginally favorable deep-layer shear with modestly strengthening northwesterly winds at mid/upper levels, should support a continued threat for isolated severe hail and strong to damaging winds as this activity spreads slowly southward across ND and northwest MN late this afternoon and early evening. 5% severe hail/wind probabilities have been included with this amendment to account for this potential. See Mesoscale Discussion 1695 for additional details on the short-term severe threat across this region. ...Previous Discussions... ...20Z Discussion... Aside from minor line adjustments to affect recent/local trends, no appreciable changes appear to be needed, with respect to the ongoing forecast. Prior reasoning continues to reflect expectations regarding convective/severe risk through the end of the period. ...1630Z Discussion... ...Mid-Atlantic states... A narrow ribbon of slightly enhanced southwesterly 500-mb flow will remain across NC/Delmarva to the southeast of a broad/weak mid-level trough centered over the Great Lakes southwestward through the Ozarks. Although large-scale forcing will be modest, a seasonably moist airmass (14-16 g/kg lowest 100-mb mean mixing ratios per 12 UTC area raobs) will gradually destabilize through the mid afternoon. Midday visible satellite imagery shows the initial stages of a building cumulus field across the Carolinas northward into eastern VA. Widely scattered to scattered thunderstorms are forecast to develop this afternoon within the moderately unstable airmass. Some strengthening in south-southwesterly 850-mb flow is progged by models later this afternoon into the early evening. A few of the stronger storms may pose a localized risk for damaging gusts (45-60 mph). If a transient supercell can develop (primarily 21-01z), a brief tornado is possible. This activity will likely diminish by mid-late evening owing to nocturnal stabilization. ...Western AZ/lower CO River Valley... Widely scattered thunderstorms are forecast to develop later this afternoon/evening as surface temperatures soar into the 100s. Although flow will be weak due to proximity to the mid- to upper-level ridge, large surface temperature-dewpoint depressions (around 50 deg F) will favor evaporative cooled downdrafts with the more robust thunderstorm cores. A few severe gusts (60-70 mph) are possible before this activity wanes by mid evening. ...Southeast New England... Model guidance indicates increased shower/thunderstorm potential late tonight (08-12 UTC) as a strengthening LLJ shifts northeastward from the Mid-Atlantic coast to near the continental shelf/deep Atlantic waters off the southeast New England coast. The latest models generally indicate meager to no surface-based buoyancy penetrating the coast, thus precluding low-severe probabilities this outlook update. ..Gleason.. 07/22/2024 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook AMEND 1 NWS Storm Prediction Center Norman OK 0502 PM CDT Mon Jul 22 2024 Valid 222155Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTH DAKOTA AND NORTHWEST MINNESOTA...THE DESERT SOUTHWEST...AND THE MID-ATLANTIC/EASTERN NORTH CAROLINA... AMENDED FOR ADDITION OF HAIL/WIND PROBABILITIES IN NORTH DAKOTA AND NORTHWEST MINNESOTA ...SUMMARY... Isolated severe thunderstorms remain possible this afternoon and early evening over portions of North Dakota and northwest Minnesota, the mid-Atlantic region, as well as western Arizona to the lower Colorado River Valley. ...North Dakota/Northwest Minnesota... Isolated strong to severe thunderstorms are ongoing along a weak boundary/low-level confluence axis across parts of northeast ND and northwest MN. A few instances of large hail have already occurred. The presence of moderate to locally strong instability, along with marginally favorable deep-layer shear with modestly strengthening northwesterly winds at mid/upper levels, should support a continued threat for isolated severe hail and strong to damaging winds as this activity spreads slowly southward across ND and northwest MN late this afternoon and early evening. 5% severe hail/wind probabilities have been included with this amendment to account for this potential. See Mesoscale Discussion 1695 for additional details on the short-term severe threat across this region. ...Previous Discussions... ...20Z Discussion... Aside from minor line adjustments to affect recent/local trends, no appreciable changes appear to be needed, with respect to the ongoing forecast. Prior reasoning continues to reflect expectations regarding convective/severe risk through the end of the period. ...1630Z Discussion... ...Mid-Atlantic states... A narrow ribbon of slightly enhanced southwesterly 500-mb flow will remain across NC/Delmarva to the southeast of a broad/weak mid-level trough centered over the Great Lakes southwestward through the Ozarks. Although large-scale forcing will be modest, a seasonably moist airmass (14-16 g/kg lowest 100-mb mean mixing ratios per 12 UTC area raobs) will gradually destabilize through the mid afternoon. Midday visible satellite imagery shows the initial stages of a building cumulus field across the Carolinas northward into eastern VA. Widely scattered to scattered thunderstorms are forecast to develop this afternoon within the moderately unstable airmass. Some strengthening in south-southwesterly 850-mb flow is progged by models later this afternoon into the early evening. A few of the stronger storms may pose a localized risk for damaging gusts (45-60 mph). If a transient supercell can develop (primarily 21-01z), a brief tornado is possible. This activity will likely diminish by mid-late evening owing to nocturnal stabilization. ...Western AZ/lower CO River Valley... Widely scattered thunderstorms are forecast to develop later this afternoon/evening as surface temperatures soar into the 100s. Although flow will be weak due to proximity to the mid- to upper-level ridge, large surface temperature-dewpoint depressions (around 50 deg F) will favor evaporative cooled downdrafts with the more robust thunderstorm cores. A few severe gusts (60-70 mph) are possible before this activity wanes by mid evening. ...Southeast New England... Model guidance indicates increased shower/thunderstorm potential late tonight (08-12 UTC) as a strengthening LLJ shifts northeastward from the Mid-Atlantic coast to near the continental shelf/deep Atlantic waters off the southeast New England coast. The latest models generally indicate meager to no surface-based buoyancy penetrating the coast, thus precluding low-severe probabilities this outlook update. ..Gleason.. 07/22/2024 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook AMEND 1 NWS Storm Prediction Center Norman OK 0502 PM CDT Mon Jul 22 2024 Valid 222155Z - 231200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTH DAKOTA AND NORTHWEST MINNESOTA...THE DESERT SOUTHWEST...AND THE MID-ATLANTIC/EASTERN NORTH CAROLINA... AMENDED FOR ADDITION OF HAIL/WIND PROBABILITIES IN NORTH DAKOTA AND NORTHWEST MINNESOTA ...SUMMARY... Isolated severe thunderstorms remain possible this afternoon and early evening over portions of North Dakota and northwest Minnesota, the mid-Atlantic region, as well as western Arizona to the lower Colorado River Valley. ...North Dakota/Northwest Minnesota... Isolated strong to severe thunderstorms are ongoing along a weak boundary/low-level confluence axis across parts of northeast ND and northwest MN. A few instances of large hail have already occurred. The presence of moderate to locally strong instability, along with marginally favorable deep-layer shear with modestly strengthening northwesterly winds at mid/upper levels, should support a continued threat for isolated severe hail and strong to damaging winds as this activity spreads slowly southward across ND and northwest MN late this afternoon and early evening. 5% severe hail/wind probabilities have been included with this amendment to account for this potential. See Mesoscale Discussion 1695 for additional details on the short-term severe threat across this region. ...Previous Discussions... ...20Z Discussion... Aside from minor line adjustments to affect recent/local trends, no appreciable changes appear to be needed, with respect to the ongoing forecast. Prior reasoning continues to reflect expectations regarding convective/severe risk through the end of the period. ...1630Z Discussion... ...Mid-Atlantic states... A narrow ribbon of slightly enhanced southwesterly 500-mb flow will remain across NC/Delmarva to the southeast of a broad/weak mid-level trough centered over the Great Lakes southwestward through the Ozarks. Although large-scale forcing will be modest, a seasonably moist airmass (14-16 g/kg lowest 100-mb mean mixing ratios per 12 UTC area raobs) will gradually destabilize through the mid afternoon. Midday visible satellite imagery shows the initial stages of a building cumulus field across the Carolinas northward into eastern VA. Widely scattered to scattered thunderstorms are forecast to develop this afternoon within the moderately unstable airmass. Some strengthening in south-southwesterly 850-mb flow is progged by models later this afternoon into the early evening. A few of the stronger storms may pose a localized risk for damaging gusts (45-60 mph). If a transient supercell can develop (primarily 21-01z), a brief tornado is possible. This activity will likely diminish by mid-late evening owing to nocturnal stabilization. ...Western AZ/lower CO River Valley... Widely scattered thunderstorms are forecast to develop later this afternoon/evening as surface temperatures soar into the 100s. Although flow will be weak due to proximity to the mid- to upper-level ridge, large surface temperature-dewpoint depressions (around 50 deg F) will favor evaporative cooled downdrafts with the more robust thunderstorm cores. A few severe gusts (60-70 mph) are possible before this activity wanes by mid evening. ...Southeast New England... Model guidance indicates increased shower/thunderstorm potential late tonight (08-12 UTC) as a strengthening LLJ shifts northeastward from the Mid-Atlantic coast to near the continental shelf/deep Atlantic waters off the southeast New England coast. The latest models generally indicate meager to no surface-based buoyancy penetrating the coast, thus precluding low-severe probabilities this outlook update. ..Gleason.. 07/22/2024 Read more