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SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0752 AM CDT Wed Aug 28 2024 Valid 281300Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE OHIO VALLEY TO THE NORTHERN MID-ATLANTIC COAST...AND ACROSS PARTS OF NORTH AND SOUTH DAKOTA... ...SUMMARY... Severe thunderstorms are expected from the Ohio Valley to the northern Mid-Atlantic Coast, and across parts of North and South Dakota. ...Synopsis... In mid/upper levels, a progressive northern-stream pattern will prevail through the period, with the main feature being a cyclone now apparent in moisture-channel imagery near the southeastern corner of BC. The associated 500-mb low should move eastward roughly along, or just north of, the international border through the period, with the accompanying trough extending south- southwestward. By 00Z, the low should be near the southwestern corner of SK, with trough to northern UT. By 12Z, the low should reach extreme south-central SK, with trough across central MT to southwestern WY. Downstream, a complex but much lower-amplitude shortwave trough was evident over Lake Superior and adjoining portions of ON and western U.P. of MI. One part of this perturbation should break eastward to the St. Lawrence Valley by the end of the period, while the trailing part drifts eastward over Lake Superior and the U.P. Of perhaps greater direct influence on convective potential, an MCV was apparent in composited radar imagery over southeastern IA. The associated perturbation should move across much of central IL today, reaching western OH by 12Z tomorrow. The 11Z surface analysis showed a cold front from northern ME west- southwestward across Lake Ontario and southern Lower MI, becoming quasistationary for the time being across southern parts of Lake Michigan and WI, to northeastern NE, then a warm front over southwestern SD, to a low over southeastern MT. This front is expected to move southeastward by 00Z to coastal NS, Cape Cod, Long Island, northern parts of MD/WV, and southern parts of OH/IN/IL, becoming a diffuse warm front northwestward over central IA, southwestern MN and central ND. There it will be overtaken by another cold front -- initially analyzed through the low over eastern MT and across northwestern WY. By 00Z, this second, stronger cold front should extend from central ND across central/ southwestern SD to east-central WY. By 12Z, the western cold front should extend from a low over southeastern ND or northeastern SD across south-central SD, western NE and northeastern CO. ...Ohio Valley to Mid-Atlantic... Widely scattered to scattered thunderstorms are expected along and south of the front today from IN to the Mid-Atlantic Coast, and perhaps the southern New England Coast/Long Island vicinity. Damaging gusts and isolated large hail will be possible. Coverage of convection is uncertain, but relative concentrations may develop downshear from what is now disorganized/nonsevere convection over OH (in the same UVV field), and ahead of the MCV over parts of IL/IN, becoming organized across parts of IN/OH. Diurnal heating of a favorably moist airmass is expected to weaken already modest ambient MLCINH along the outlook corridor by late morning. With lift along the front and prefrontal outflow/differential-heating boundaries, growth of morning to early afternoon development into one or more complexes appears to be a plausible scenario, rendering a greater wind than hail threat. Surface dewpoints commonly in the mid 60s to low 70s F will offset modest mid/upper-level lapse rates enough to contribute to peak/preconvective MLCAPE in the 800-1500 J/kg range from OH eastward, and 1000-2000 J/kg back into portions of IN. Weak, generally veered low/middle-level flow will limit vertical shear. Still, nearly unidirectional westerly flow through a deep layer will foster movement of convection parallel to the low-level moisture-instability axis. ...Dakotas... A line or arc of scattered thunderstorms should develop along/near the cold front during late afternoon into evening, perhaps initially over ND where deep-layer forcing will be stronger, then southward into greater capping in SD, as the front impinges on greater moisture and lingering boundary-layer instability. Ahead of the cold front, enough easterly component to near-surface flow will develop to support moist advection into the convective genesis zone, with surface dewpoints into the 60s F becoming common. Capping at the base of a modest EML will suppress development for much of the afternoon, especially over SD, but once frontal lift overcomes it, a corridor of 2000-3000 J/kg MLCAPE should be available southwest of (and parallel to) the warm front. Though the strongest flow aloft and large-scale ascent will remain behind the cold front, the eastern rim of stronger height falls will spread over the frontal zone, with enough mass response to both foster favorable vertical shear for supercells and enhanced storm-relative flow in low levels. Effective-shear magnitudes of 30-40 kt (locally higher) and broad low-level hodographs along and south of the warm front should foster supercell development, until mergers and upscale growth occur. Large to very large hail and severe gusts will be the main concerns, though a tornado is possible. However, relatively weak midlevel flow may encourage a transition to messier, quasi- linear mode with embedded LEWP/bow formations for a few hours. Activity should weaken overnight as it moves into stabilizing boundary-layer air, though a 45-55-kt LLJ may encourage persistence of a cluster or two tonight into the eastern Dakotas. ..Edwards/Bentley.. 08/28/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0752 AM CDT Wed Aug 28 2024 Valid 281300Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE OHIO VALLEY TO THE NORTHERN MID-ATLANTIC COAST...AND ACROSS PARTS OF NORTH AND SOUTH DAKOTA... ...SUMMARY... Severe thunderstorms are expected from the Ohio Valley to the northern Mid-Atlantic Coast, and across parts of North and South Dakota. ...Synopsis... In mid/upper levels, a progressive northern-stream pattern will prevail through the period, with the main feature being a cyclone now apparent in moisture-channel imagery near the southeastern corner of BC. The associated 500-mb low should move eastward roughly along, or just north of, the international border through the period, with the accompanying trough extending south- southwestward. By 00Z, the low should be near the southwestern corner of SK, with trough to northern UT. By 12Z, the low should reach extreme south-central SK, with trough across central MT to southwestern WY. Downstream, a complex but much lower-amplitude shortwave trough was evident over Lake Superior and adjoining portions of ON and western U.P. of MI. One part of this perturbation should break eastward to the St. Lawrence Valley by the end of the period, while the trailing part drifts eastward over Lake Superior and the U.P. Of perhaps greater direct influence on convective potential, an MCV was apparent in composited radar imagery over southeastern IA. The associated perturbation should move across much of central IL today, reaching western OH by 12Z tomorrow. The 11Z surface analysis showed a cold front from northern ME west- southwestward across Lake Ontario and southern Lower MI, becoming quasistationary for the time being across southern parts of Lake Michigan and WI, to northeastern NE, then a warm front over southwestern SD, to a low over southeastern MT. This front is expected to move southeastward by 00Z to coastal NS, Cape Cod, Long Island, northern parts of MD/WV, and southern parts of OH/IN/IL, becoming a diffuse warm front northwestward over central IA, southwestern MN and central ND. There it will be overtaken by another cold front -- initially analyzed through the low over eastern MT and across northwestern WY. By 00Z, this second, stronger cold front should extend from central ND across central/ southwestern SD to east-central WY. By 12Z, the western cold front should extend from a low over southeastern ND or northeastern SD across south-central SD, western NE and northeastern CO. ...Ohio Valley to Mid-Atlantic... Widely scattered to scattered thunderstorms are expected along and south of the front today from IN to the Mid-Atlantic Coast, and perhaps the southern New England Coast/Long Island vicinity. Damaging gusts and isolated large hail will be possible. Coverage of convection is uncertain, but relative concentrations may develop downshear from what is now disorganized/nonsevere convection over OH (in the same UVV field), and ahead of the MCV over parts of IL/IN, becoming organized across parts of IN/OH. Diurnal heating of a favorably moist airmass is expected to weaken already modest ambient MLCINH along the outlook corridor by late morning. With lift along the front and prefrontal outflow/differential-heating boundaries, growth of morning to early afternoon development into one or more complexes appears to be a plausible scenario, rendering a greater wind than hail threat. Surface dewpoints commonly in the mid 60s to low 70s F will offset modest mid/upper-level lapse rates enough to contribute to peak/preconvective MLCAPE in the 800-1500 J/kg range from OH eastward, and 1000-2000 J/kg back into portions of IN. Weak, generally veered low/middle-level flow will limit vertical shear. Still, nearly unidirectional westerly flow through a deep layer will foster movement of convection parallel to the low-level moisture-instability axis. ...Dakotas... A line or arc of scattered thunderstorms should develop along/near the cold front during late afternoon into evening, perhaps initially over ND where deep-layer forcing will be stronger, then southward into greater capping in SD, as the front impinges on greater moisture and lingering boundary-layer instability. Ahead of the cold front, enough easterly component to near-surface flow will develop to support moist advection into the convective genesis zone, with surface dewpoints into the 60s F becoming common. Capping at the base of a modest EML will suppress development for much of the afternoon, especially over SD, but once frontal lift overcomes it, a corridor of 2000-3000 J/kg MLCAPE should be available southwest of (and parallel to) the warm front. Though the strongest flow aloft and large-scale ascent will remain behind the cold front, the eastern rim of stronger height falls will spread over the frontal zone, with enough mass response to both foster favorable vertical shear for supercells and enhanced storm-relative flow in low levels. Effective-shear magnitudes of 30-40 kt (locally higher) and broad low-level hodographs along and south of the warm front should foster supercell development, until mergers and upscale growth occur. Large to very large hail and severe gusts will be the main concerns, though a tornado is possible. However, relatively weak midlevel flow may encourage a transition to messier, quasi- linear mode with embedded LEWP/bow formations for a few hours. Activity should weaken overnight as it moves into stabilizing boundary-layer air, though a 45-55-kt LLJ may encourage persistence of a cluster or two tonight into the eastern Dakotas. ..Edwards/Bentley.. 08/28/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0752 AM CDT Wed Aug 28 2024 Valid 281300Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE OHIO VALLEY TO THE NORTHERN MID-ATLANTIC COAST...AND ACROSS PARTS OF NORTH AND SOUTH DAKOTA... ...SUMMARY... Severe thunderstorms are expected from the Ohio Valley to the northern Mid-Atlantic Coast, and across parts of North and South Dakota. ...Synopsis... In mid/upper levels, a progressive northern-stream pattern will prevail through the period, with the main feature being a cyclone now apparent in moisture-channel imagery near the southeastern corner of BC. The associated 500-mb low should move eastward roughly along, or just north of, the international border through the period, with the accompanying trough extending south- southwestward. By 00Z, the low should be near the southwestern corner of SK, with trough to northern UT. By 12Z, the low should reach extreme south-central SK, with trough across central MT to southwestern WY. Downstream, a complex but much lower-amplitude shortwave trough was evident over Lake Superior and adjoining portions of ON and western U.P. of MI. One part of this perturbation should break eastward to the St. Lawrence Valley by the end of the period, while the trailing part drifts eastward over Lake Superior and the U.P. Of perhaps greater direct influence on convective potential, an MCV was apparent in composited radar imagery over southeastern IA. The associated perturbation should move across much of central IL today, reaching western OH by 12Z tomorrow. The 11Z surface analysis showed a cold front from northern ME west- southwestward across Lake Ontario and southern Lower MI, becoming quasistationary for the time being across southern parts of Lake Michigan and WI, to northeastern NE, then a warm front over southwestern SD, to a low over southeastern MT. This front is expected to move southeastward by 00Z to coastal NS, Cape Cod, Long Island, northern parts of MD/WV, and southern parts of OH/IN/IL, becoming a diffuse warm front northwestward over central IA, southwestern MN and central ND. There it will be overtaken by another cold front -- initially analyzed through the low over eastern MT and across northwestern WY. By 00Z, this second, stronger cold front should extend from central ND across central/ southwestern SD to east-central WY. By 12Z, the western cold front should extend from a low over southeastern ND or northeastern SD across south-central SD, western NE and northeastern CO. ...Ohio Valley to Mid-Atlantic... Widely scattered to scattered thunderstorms are expected along and south of the front today from IN to the Mid-Atlantic Coast, and perhaps the southern New England Coast/Long Island vicinity. Damaging gusts and isolated large hail will be possible. Coverage of convection is uncertain, but relative concentrations may develop downshear from what is now disorganized/nonsevere convection over OH (in the same UVV field), and ahead of the MCV over parts of IL/IN, becoming organized across parts of IN/OH. Diurnal heating of a favorably moist airmass is expected to weaken already modest ambient MLCINH along the outlook corridor by late morning. With lift along the front and prefrontal outflow/differential-heating boundaries, growth of morning to early afternoon development into one or more complexes appears to be a plausible scenario, rendering a greater wind than hail threat. Surface dewpoints commonly in the mid 60s to low 70s F will offset modest mid/upper-level lapse rates enough to contribute to peak/preconvective MLCAPE in the 800-1500 J/kg range from OH eastward, and 1000-2000 J/kg back into portions of IN. Weak, generally veered low/middle-level flow will limit vertical shear. Still, nearly unidirectional westerly flow through a deep layer will foster movement of convection parallel to the low-level moisture-instability axis. ...Dakotas... A line or arc of scattered thunderstorms should develop along/near the cold front during late afternoon into evening, perhaps initially over ND where deep-layer forcing will be stronger, then southward into greater capping in SD, as the front impinges on greater moisture and lingering boundary-layer instability. Ahead of the cold front, enough easterly component to near-surface flow will develop to support moist advection into the convective genesis zone, with surface dewpoints into the 60s F becoming common. Capping at the base of a modest EML will suppress development for much of the afternoon, especially over SD, but once frontal lift overcomes it, a corridor of 2000-3000 J/kg MLCAPE should be available southwest of (and parallel to) the warm front. Though the strongest flow aloft and large-scale ascent will remain behind the cold front, the eastern rim of stronger height falls will spread over the frontal zone, with enough mass response to both foster favorable vertical shear for supercells and enhanced storm-relative flow in low levels. Effective-shear magnitudes of 30-40 kt (locally higher) and broad low-level hodographs along and south of the warm front should foster supercell development, until mergers and upscale growth occur. Large to very large hail and severe gusts will be the main concerns, though a tornado is possible. However, relatively weak midlevel flow may encourage a transition to messier, quasi- linear mode with embedded LEWP/bow formations for a few hours. Activity should weaken overnight as it moves into stabilizing boundary-layer air, though a 45-55-kt LLJ may encourage persistence of a cluster or two tonight into the eastern Dakotas. ..Edwards/Bentley.. 08/28/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0752 AM CDT Wed Aug 28 2024 Valid 281300Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE OHIO VALLEY TO THE NORTHERN MID-ATLANTIC COAST...AND ACROSS PARTS OF NORTH AND SOUTH DAKOTA... ...SUMMARY... Severe thunderstorms are expected from the Ohio Valley to the northern Mid-Atlantic Coast, and across parts of North and South Dakota. ...Synopsis... In mid/upper levels, a progressive northern-stream pattern will prevail through the period, with the main feature being a cyclone now apparent in moisture-channel imagery near the southeastern corner of BC. The associated 500-mb low should move eastward roughly along, or just north of, the international border through the period, with the accompanying trough extending south- southwestward. By 00Z, the low should be near the southwestern corner of SK, with trough to northern UT. By 12Z, the low should reach extreme south-central SK, with trough across central MT to southwestern WY. Downstream, a complex but much lower-amplitude shortwave trough was evident over Lake Superior and adjoining portions of ON and western U.P. of MI. One part of this perturbation should break eastward to the St. Lawrence Valley by the end of the period, while the trailing part drifts eastward over Lake Superior and the U.P. Of perhaps greater direct influence on convective potential, an MCV was apparent in composited radar imagery over southeastern IA. The associated perturbation should move across much of central IL today, reaching western OH by 12Z tomorrow. The 11Z surface analysis showed a cold front from northern ME west- southwestward across Lake Ontario and southern Lower MI, becoming quasistationary for the time being across southern parts of Lake Michigan and WI, to northeastern NE, then a warm front over southwestern SD, to a low over southeastern MT. This front is expected to move southeastward by 00Z to coastal NS, Cape Cod, Long Island, northern parts of MD/WV, and southern parts of OH/IN/IL, becoming a diffuse warm front northwestward over central IA, southwestern MN and central ND. There it will be overtaken by another cold front -- initially analyzed through the low over eastern MT and across northwestern WY. By 00Z, this second, stronger cold front should extend from central ND across central/ southwestern SD to east-central WY. By 12Z, the western cold front should extend from a low over southeastern ND or northeastern SD across south-central SD, western NE and northeastern CO. ...Ohio Valley to Mid-Atlantic... Widely scattered to scattered thunderstorms are expected along and south of the front today from IN to the Mid-Atlantic Coast, and perhaps the southern New England Coast/Long Island vicinity. Damaging gusts and isolated large hail will be possible. Coverage of convection is uncertain, but relative concentrations may develop downshear from what is now disorganized/nonsevere convection over OH (in the same UVV field), and ahead of the MCV over parts of IL/IN, becoming organized across parts of IN/OH. Diurnal heating of a favorably moist airmass is expected to weaken already modest ambient MLCINH along the outlook corridor by late morning. With lift along the front and prefrontal outflow/differential-heating boundaries, growth of morning to early afternoon development into one or more complexes appears to be a plausible scenario, rendering a greater wind than hail threat. Surface dewpoints commonly in the mid 60s to low 70s F will offset modest mid/upper-level lapse rates enough to contribute to peak/preconvective MLCAPE in the 800-1500 J/kg range from OH eastward, and 1000-2000 J/kg back into portions of IN. Weak, generally veered low/middle-level flow will limit vertical shear. Still, nearly unidirectional westerly flow through a deep layer will foster movement of convection parallel to the low-level moisture-instability axis. ...Dakotas... A line or arc of scattered thunderstorms should develop along/near the cold front during late afternoon into evening, perhaps initially over ND where deep-layer forcing will be stronger, then southward into greater capping in SD, as the front impinges on greater moisture and lingering boundary-layer instability. Ahead of the cold front, enough easterly component to near-surface flow will develop to support moist advection into the convective genesis zone, with surface dewpoints into the 60s F becoming common. Capping at the base of a modest EML will suppress development for much of the afternoon, especially over SD, but once frontal lift overcomes it, a corridor of 2000-3000 J/kg MLCAPE should be available southwest of (and parallel to) the warm front. Though the strongest flow aloft and large-scale ascent will remain behind the cold front, the eastern rim of stronger height falls will spread over the frontal zone, with enough mass response to both foster favorable vertical shear for supercells and enhanced storm-relative flow in low levels. Effective-shear magnitudes of 30-40 kt (locally higher) and broad low-level hodographs along and south of the warm front should foster supercell development, until mergers and upscale growth occur. Large to very large hail and severe gusts will be the main concerns, though a tornado is possible. However, relatively weak midlevel flow may encourage a transition to messier, quasi- linear mode with embedded LEWP/bow formations for a few hours. Activity should weaken overnight as it moves into stabilizing boundary-layer air, though a 45-55-kt LLJ may encourage persistence of a cluster or two tonight into the eastern Dakotas. ..Edwards/Bentley.. 08/28/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0752 AM CDT Wed Aug 28 2024 Valid 281300Z - 291200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE OHIO VALLEY TO THE NORTHERN MID-ATLANTIC COAST...AND ACROSS PARTS OF NORTH AND SOUTH DAKOTA... ...SUMMARY... Severe thunderstorms are expected from the Ohio Valley to the northern Mid-Atlantic Coast, and across parts of North and South Dakota. ...Synopsis... In mid/upper levels, a progressive northern-stream pattern will prevail through the period, with the main feature being a cyclone now apparent in moisture-channel imagery near the southeastern corner of BC. The associated 500-mb low should move eastward roughly along, or just north of, the international border through the period, with the accompanying trough extending south- southwestward. By 00Z, the low should be near the southwestern corner of SK, with trough to northern UT. By 12Z, the low should reach extreme south-central SK, with trough across central MT to southwestern WY. Downstream, a complex but much lower-amplitude shortwave trough was evident over Lake Superior and adjoining portions of ON and western U.P. of MI. One part of this perturbation should break eastward to the St. Lawrence Valley by the end of the period, while the trailing part drifts eastward over Lake Superior and the U.P. Of perhaps greater direct influence on convective potential, an MCV was apparent in composited radar imagery over southeastern IA. The associated perturbation should move across much of central IL today, reaching western OH by 12Z tomorrow. The 11Z surface analysis showed a cold front from northern ME west- southwestward across Lake Ontario and southern Lower MI, becoming quasistationary for the time being across southern parts of Lake Michigan and WI, to northeastern NE, then a warm front over southwestern SD, to a low over southeastern MT. This front is expected to move southeastward by 00Z to coastal NS, Cape Cod, Long Island, northern parts of MD/WV, and southern parts of OH/IN/IL, becoming a diffuse warm front northwestward over central IA, southwestern MN and central ND. There it will be overtaken by another cold front -- initially analyzed through the low over eastern MT and across northwestern WY. By 00Z, this second, stronger cold front should extend from central ND across central/ southwestern SD to east-central WY. By 12Z, the western cold front should extend from a low over southeastern ND or northeastern SD across south-central SD, western NE and northeastern CO. ...Ohio Valley to Mid-Atlantic... Widely scattered to scattered thunderstorms are expected along and south of the front today from IN to the Mid-Atlantic Coast, and perhaps the southern New England Coast/Long Island vicinity. Damaging gusts and isolated large hail will be possible. Coverage of convection is uncertain, but relative concentrations may develop downshear from what is now disorganized/nonsevere convection over OH (in the same UVV field), and ahead of the MCV over parts of IL/IN, becoming organized across parts of IN/OH. Diurnal heating of a favorably moist airmass is expected to weaken already modest ambient MLCINH along the outlook corridor by late morning. With lift along the front and prefrontal outflow/differential-heating boundaries, growth of morning to early afternoon development into one or more complexes appears to be a plausible scenario, rendering a greater wind than hail threat. Surface dewpoints commonly in the mid 60s to low 70s F will offset modest mid/upper-level lapse rates enough to contribute to peak/preconvective MLCAPE in the 800-1500 J/kg range from OH eastward, and 1000-2000 J/kg back into portions of IN. Weak, generally veered low/middle-level flow will limit vertical shear. Still, nearly unidirectional westerly flow through a deep layer will foster movement of convection parallel to the low-level moisture-instability axis. ...Dakotas... A line or arc of scattered thunderstorms should develop along/near the cold front during late afternoon into evening, perhaps initially over ND where deep-layer forcing will be stronger, then southward into greater capping in SD, as the front impinges on greater moisture and lingering boundary-layer instability. Ahead of the cold front, enough easterly component to near-surface flow will develop to support moist advection into the convective genesis zone, with surface dewpoints into the 60s F becoming common. Capping at the base of a modest EML will suppress development for much of the afternoon, especially over SD, but once frontal lift overcomes it, a corridor of 2000-3000 J/kg MLCAPE should be available southwest of (and parallel to) the warm front. Though the strongest flow aloft and large-scale ascent will remain behind the cold front, the eastern rim of stronger height falls will spread over the frontal zone, with enough mass response to both foster favorable vertical shear for supercells and enhanced storm-relative flow in low levels. Effective-shear magnitudes of 30-40 kt (locally higher) and broad low-level hodographs along and south of the warm front should foster supercell development, until mergers and upscale growth occur. Large to very large hail and severe gusts will be the main concerns, though a tornado is possible. However, relatively weak midlevel flow may encourage a transition to messier, quasi- linear mode with embedded LEWP/bow formations for a few hours. Activity should weaken overnight as it moves into stabilizing boundary-layer air, though a 45-55-kt LLJ may encourage persistence of a cluster or two tonight into the eastern Dakotas. ..Edwards/Bentley.. 08/28/2024 Read more

Fields of corn and soybeans in the Williamsport area were yellow and dry. The farmer thinks that he will be lucky if he gets half a crop. WKRN.com (Nashville, Tenn.), Aug 28, 2024

Union Parish enacted a burn ban until further notice as moderate drought took hold in the area. NOLA.com (New Orleans, La.), Aug 28, 2024

000
ABPZ20 KNHC 281114
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 AM PDT Wed Aug 28 2024

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

Active Systems:
The National Hurricane Center is issuing advisories on Tropical
Storm Hector, located about midway between the southern tip of the
Baja California peninsula and the Hawaiian Islands.

Tropical cyclone formation is not expected during the next 7 days.

$$
Forecaster Hagen/Reinhart

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0356 AM CDT Wed Aug 28 2024 Valid 311200Z - 051200Z ...DISCUSSION... Medium-range global models continue to suggest limited severe potential Days 4-5 (Saturday and Sunday) largely within the northeastern quarter of the country, followed by several days of what appears likely to be minimal severe risk through the remainder of the period. Day 4/Saturday, upper-level height falls are progged to shift across the Great Lakes/Midwest/Northeast, as a strengthening upper trough advances east-southeastward across Ontario and the Upper Great Lakes region. A weak cold front will cross the Lower Great Lakes/Appalachians, with likelihood for showers and thunderstorms accompanying this front. However, with stronger flow aloft limited to areas from Pennsylvania northward, where instability should remain limited, overall severe risk appears at this time to remain too low to warrant inclusion of a risk area associated with this frontal passage. Limited severe potential may also exist for a few hours in the afternoon and early evening over the Upper Mississippi Valley area, as a stronger/reinforcing cold front surges southeastward out of Canada across the Upper Mississippi Valley and Great Lakes region and into central Plains and Upper Midwest overnight. Though only modest moisture -- and thus weak afternoon pre-frontal destabilization -- is expected, low-topped convection is expected during the afternoon across parts of Upper Michigan/Wisconsin and perhaps Minnesota. Strong northwesterly flow aloft would support fast-moving storms, and possibly a risk for damaging winds locally. Again though, this potential appears too limited/uncertain to include a risk area at this time. Day 5, the surging cold front is forecast to shift southeastward into the Northeast/New England, and southward across the Ohio Valley area. Similar to Day 4 potential for low-topped storms farther northwest, convection will likely develop along the front through the afternoon -- particularly across the New England vicinity. However, given the frontal passage the prior day, questions with respect to available moisture -- and thus destabilization potential -- exist at this time. As such, despite the strong front and strong flow aloft, severe risk again appears limited and uncertain, precluding introduction of a risk area for now. The cold front is expected to have moved offshore of New England and the Mid-Atlantic region by the start of Day 6, becoming quasistationary in a west-to-east manner across the Southeast and Mid South, on the southern fringe of a Canadian High settling into the northeastern quarter of the country. While convection will likely occur near and south of this front where moist Gulf air will remain in place, this region will remain well south of the enhanced flow aloft. Therefore, severe risk appears minimal -- and should remain so through the end of the period. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0356 AM CDT Wed Aug 28 2024 Valid 311200Z - 051200Z ...DISCUSSION... Medium-range global models continue to suggest limited severe potential Days 4-5 (Saturday and Sunday) largely within the northeastern quarter of the country, followed by several days of what appears likely to be minimal severe risk through the remainder of the period. Day 4/Saturday, upper-level height falls are progged to shift across the Great Lakes/Midwest/Northeast, as a strengthening upper trough advances east-southeastward across Ontario and the Upper Great Lakes region. A weak cold front will cross the Lower Great Lakes/Appalachians, with likelihood for showers and thunderstorms accompanying this front. However, with stronger flow aloft limited to areas from Pennsylvania northward, where instability should remain limited, overall severe risk appears at this time to remain too low to warrant inclusion of a risk area associated with this frontal passage. Limited severe potential may also exist for a few hours in the afternoon and early evening over the Upper Mississippi Valley area, as a stronger/reinforcing cold front surges southeastward out of Canada across the Upper Mississippi Valley and Great Lakes region and into central Plains and Upper Midwest overnight. Though only modest moisture -- and thus weak afternoon pre-frontal destabilization -- is expected, low-topped convection is expected during the afternoon across parts of Upper Michigan/Wisconsin and perhaps Minnesota. Strong northwesterly flow aloft would support fast-moving storms, and possibly a risk for damaging winds locally. Again though, this potential appears too limited/uncertain to include a risk area at this time. Day 5, the surging cold front is forecast to shift southeastward into the Northeast/New England, and southward across the Ohio Valley area. Similar to Day 4 potential for low-topped storms farther northwest, convection will likely develop along the front through the afternoon -- particularly across the New England vicinity. However, given the frontal passage the prior day, questions with respect to available moisture -- and thus destabilization potential -- exist at this time. As such, despite the strong front and strong flow aloft, severe risk again appears limited and uncertain, precluding introduction of a risk area for now. The cold front is expected to have moved offshore of New England and the Mid-Atlantic region by the start of Day 6, becoming quasistationary in a west-to-east manner across the Southeast and Mid South, on the southern fringe of a Canadian High settling into the northeastern quarter of the country. While convection will likely occur near and south of this front where moist Gulf air will remain in place, this region will remain well south of the enhanced flow aloft. Therefore, severe risk appears minimal -- and should remain so through the end of the period. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0356 AM CDT Wed Aug 28 2024 Valid 311200Z - 051200Z ...DISCUSSION... Medium-range global models continue to suggest limited severe potential Days 4-5 (Saturday and Sunday) largely within the northeastern quarter of the country, followed by several days of what appears likely to be minimal severe risk through the remainder of the period. Day 4/Saturday, upper-level height falls are progged to shift across the Great Lakes/Midwest/Northeast, as a strengthening upper trough advances east-southeastward across Ontario and the Upper Great Lakes region. A weak cold front will cross the Lower Great Lakes/Appalachians, with likelihood for showers and thunderstorms accompanying this front. However, with stronger flow aloft limited to areas from Pennsylvania northward, where instability should remain limited, overall severe risk appears at this time to remain too low to warrant inclusion of a risk area associated with this frontal passage. Limited severe potential may also exist for a few hours in the afternoon and early evening over the Upper Mississippi Valley area, as a stronger/reinforcing cold front surges southeastward out of Canada across the Upper Mississippi Valley and Great Lakes region and into central Plains and Upper Midwest overnight. Though only modest moisture -- and thus weak afternoon pre-frontal destabilization -- is expected, low-topped convection is expected during the afternoon across parts of Upper Michigan/Wisconsin and perhaps Minnesota. Strong northwesterly flow aloft would support fast-moving storms, and possibly a risk for damaging winds locally. Again though, this potential appears too limited/uncertain to include a risk area at this time. Day 5, the surging cold front is forecast to shift southeastward into the Northeast/New England, and southward across the Ohio Valley area. Similar to Day 4 potential for low-topped storms farther northwest, convection will likely develop along the front through the afternoon -- particularly across the New England vicinity. However, given the frontal passage the prior day, questions with respect to available moisture -- and thus destabilization potential -- exist at this time. As such, despite the strong front and strong flow aloft, severe risk again appears limited and uncertain, precluding introduction of a risk area for now. The cold front is expected to have moved offshore of New England and the Mid-Atlantic region by the start of Day 6, becoming quasistationary in a west-to-east manner across the Southeast and Mid South, on the southern fringe of a Canadian High settling into the northeastern quarter of the country. While convection will likely occur near and south of this front where moist Gulf air will remain in place, this region will remain well south of the enhanced flow aloft. Therefore, severe risk appears minimal -- and should remain so through the end of the period. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0356 AM CDT Wed Aug 28 2024 Valid 311200Z - 051200Z ...DISCUSSION... Medium-range global models continue to suggest limited severe potential Days 4-5 (Saturday and Sunday) largely within the northeastern quarter of the country, followed by several days of what appears likely to be minimal severe risk through the remainder of the period. Day 4/Saturday, upper-level height falls are progged to shift across the Great Lakes/Midwest/Northeast, as a strengthening upper trough advances east-southeastward across Ontario and the Upper Great Lakes region. A weak cold front will cross the Lower Great Lakes/Appalachians, with likelihood for showers and thunderstorms accompanying this front. However, with stronger flow aloft limited to areas from Pennsylvania northward, where instability should remain limited, overall severe risk appears at this time to remain too low to warrant inclusion of a risk area associated with this frontal passage. Limited severe potential may also exist for a few hours in the afternoon and early evening over the Upper Mississippi Valley area, as a stronger/reinforcing cold front surges southeastward out of Canada across the Upper Mississippi Valley and Great Lakes region and into central Plains and Upper Midwest overnight. Though only modest moisture -- and thus weak afternoon pre-frontal destabilization -- is expected, low-topped convection is expected during the afternoon across parts of Upper Michigan/Wisconsin and perhaps Minnesota. Strong northwesterly flow aloft would support fast-moving storms, and possibly a risk for damaging winds locally. Again though, this potential appears too limited/uncertain to include a risk area at this time. Day 5, the surging cold front is forecast to shift southeastward into the Northeast/New England, and southward across the Ohio Valley area. Similar to Day 4 potential for low-topped storms farther northwest, convection will likely develop along the front through the afternoon -- particularly across the New England vicinity. However, given the frontal passage the prior day, questions with respect to available moisture -- and thus destabilization potential -- exist at this time. As such, despite the strong front and strong flow aloft, severe risk again appears limited and uncertain, precluding introduction of a risk area for now. The cold front is expected to have moved offshore of New England and the Mid-Atlantic region by the start of Day 6, becoming quasistationary in a west-to-east manner across the Southeast and Mid South, on the southern fringe of a Canadian High settling into the northeastern quarter of the country. While convection will likely occur near and south of this front where moist Gulf air will remain in place, this region will remain well south of the enhanced flow aloft. Therefore, severe risk appears minimal -- and should remain so through the end of the period. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0356 AM CDT Wed Aug 28 2024 Valid 311200Z - 051200Z ...DISCUSSION... Medium-range global models continue to suggest limited severe potential Days 4-5 (Saturday and Sunday) largely within the northeastern quarter of the country, followed by several days of what appears likely to be minimal severe risk through the remainder of the period. Day 4/Saturday, upper-level height falls are progged to shift across the Great Lakes/Midwest/Northeast, as a strengthening upper trough advances east-southeastward across Ontario and the Upper Great Lakes region. A weak cold front will cross the Lower Great Lakes/Appalachians, with likelihood for showers and thunderstorms accompanying this front. However, with stronger flow aloft limited to areas from Pennsylvania northward, where instability should remain limited, overall severe risk appears at this time to remain too low to warrant inclusion of a risk area associated with this frontal passage. Limited severe potential may also exist for a few hours in the afternoon and early evening over the Upper Mississippi Valley area, as a stronger/reinforcing cold front surges southeastward out of Canada across the Upper Mississippi Valley and Great Lakes region and into central Plains and Upper Midwest overnight. Though only modest moisture -- and thus weak afternoon pre-frontal destabilization -- is expected, low-topped convection is expected during the afternoon across parts of Upper Michigan/Wisconsin and perhaps Minnesota. Strong northwesterly flow aloft would support fast-moving storms, and possibly a risk for damaging winds locally. Again though, this potential appears too limited/uncertain to include a risk area at this time. Day 5, the surging cold front is forecast to shift southeastward into the Northeast/New England, and southward across the Ohio Valley area. Similar to Day 4 potential for low-topped storms farther northwest, convection will likely develop along the front through the afternoon -- particularly across the New England vicinity. However, given the frontal passage the prior day, questions with respect to available moisture -- and thus destabilization potential -- exist at this time. As such, despite the strong front and strong flow aloft, severe risk again appears limited and uncertain, precluding introduction of a risk area for now. The cold front is expected to have moved offshore of New England and the Mid-Atlantic region by the start of Day 6, becoming quasistationary in a west-to-east manner across the Southeast and Mid South, on the southern fringe of a Canadian High settling into the northeastern quarter of the country. While convection will likely occur near and south of this front where moist Gulf air will remain in place, this region will remain well south of the enhanced flow aloft. Therefore, severe risk appears minimal -- and should remain so through the end of the period. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0356 AM CDT Wed Aug 28 2024 Valid 311200Z - 051200Z ...DISCUSSION... Medium-range global models continue to suggest limited severe potential Days 4-5 (Saturday and Sunday) largely within the northeastern quarter of the country, followed by several days of what appears likely to be minimal severe risk through the remainder of the period. Day 4/Saturday, upper-level height falls are progged to shift across the Great Lakes/Midwest/Northeast, as a strengthening upper trough advances east-southeastward across Ontario and the Upper Great Lakes region. A weak cold front will cross the Lower Great Lakes/Appalachians, with likelihood for showers and thunderstorms accompanying this front. However, with stronger flow aloft limited to areas from Pennsylvania northward, where instability should remain limited, overall severe risk appears at this time to remain too low to warrant inclusion of a risk area associated with this frontal passage. Limited severe potential may also exist for a few hours in the afternoon and early evening over the Upper Mississippi Valley area, as a stronger/reinforcing cold front surges southeastward out of Canada across the Upper Mississippi Valley and Great Lakes region and into central Plains and Upper Midwest overnight. Though only modest moisture -- and thus weak afternoon pre-frontal destabilization -- is expected, low-topped convection is expected during the afternoon across parts of Upper Michigan/Wisconsin and perhaps Minnesota. Strong northwesterly flow aloft would support fast-moving storms, and possibly a risk for damaging winds locally. Again though, this potential appears too limited/uncertain to include a risk area at this time. Day 5, the surging cold front is forecast to shift southeastward into the Northeast/New England, and southward across the Ohio Valley area. Similar to Day 4 potential for low-topped storms farther northwest, convection will likely develop along the front through the afternoon -- particularly across the New England vicinity. However, given the frontal passage the prior day, questions with respect to available moisture -- and thus destabilization potential -- exist at this time. As such, despite the strong front and strong flow aloft, severe risk again appears limited and uncertain, precluding introduction of a risk area for now. The cold front is expected to have moved offshore of New England and the Mid-Atlantic region by the start of Day 6, becoming quasistationary in a west-to-east manner across the Southeast and Mid South, on the southern fringe of a Canadian High settling into the northeastern quarter of the country. While convection will likely occur near and south of this front where moist Gulf air will remain in place, this region will remain well south of the enhanced flow aloft. Therefore, severe risk appears minimal -- and should remain so through the end of the period. Read more

5-Day Uncertainty Track last updated Wed, 28 Aug 2024 08:35:32 GMT


Wind Speed Probabilities last updated Wed, 28 Aug 2024 09:36:49 GMT

Issued at 1100 PM HST Tue Aug 27 2024 000 WTPZ43 KNHC 280834 TCDEP3 Tropical Storm Hector Discussion Number 11 NWS National Hurricane Center Miami FL EP082024 1100 PM HST Tue Aug 27 2024 Hector continues to produce a large area of deep convection, although it has become a little less organized this evening. Recent microwave imagery depicts that the system is starting to tilt due to 15-20 kt of westerly wind shear. A recent scatterometer pass of ASCAT-B depicted satellite derived winds around 38-40 kt. Subjective and objective intensity estimates have held steady for this advisory and range from 40-45 kt. Using a blend of ASCAT data and the intensity estimates, the intensity is held at 45 kt for this advisory. The tropical storm continues to move west-northwestward at 285/10 kt. The mid-level ridge ridge to the north will keep Hector on a west-northwestward to westward motion the next day or so. As the system weakens and becomes vertically shallow a more westward motion will occur as the system is steered in the low-level flow. The model guidance is in fairly good agreement and the latest NHC track forecast is very close to the previous advisory. Atmospheric and oceanic conditions near the system are not very favorable as Hector will continue to deal with westerly wind shear, drier air, and moves over sub 26C sea surface temperatures. This should cause Hector to gradually weaken over the next few days. Global models are in fairly good agreement that the system will struggle to produce organized deep convection in about 36 h, and open into a trough and dissipate in 60 h. This is reflected in the latest NHC intensity forecast, which lies near the consensus aids. FORECAST POSITIONS AND MAX WINDS INIT 28/0900Z 18.4N 132.0W 45 KT 50 MPH 12H 28/1800Z 18.5N 133.7W 40 KT 45 MPH 24H 29/0600Z 18.6N 135.8W 35 KT 40 MPH 36H 29/1800Z 18.6N 138.4W 30 KT 35 MPH...POST-TROP/REMNT LOW 48H 30/0600Z 18.5N 141.1W 30 KT 35 MPH...POST-TROP/REMNT LOW 60H 30/1800Z...DISSIPATED $$ Forecaster Kelly

Issued at 0900 UTC WED AUG 28 2024 000 FOPZ13 KNHC 280834 PWSEP3 TROPICAL STORM HECTOR WIND SPEED PROBABILITIES NUMBER 11 NWS NATIONAL HURRICANE CENTER MIAMI FL EP082024 0900 UTC WED AUG 28 2024 AT 0900Z THE CENTER OF TROPICAL STORM HECTOR WAS LOCATED NEAR LATITUDE 18.4 NORTH...LONGITUDE 132.0 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 45 KTS...50 MPH...85 KM/H. Z INDICATES COORDINATED UNIVERSAL TIME (GREENWICH) PACIFIC DAYLIGHT TIME (PDT)...SUBTRACT 7 HOURS FROM Z TIME HAWAIIAN STANDARD TIME (HST)...SUBTRACT 10 HOURS FROM Z TIME WIND SPEED PROBABILITY TABLE FOR SPECIFIC LOCATIONS CHANCES OF SUSTAINED (1-MINUTE AVERAGE) WIND SPEEDS OF AT LEAST ...34 KT (39 MPH... 63 KM/H)... ...50 KT (58 MPH... 93 KM/H)... ...64 KT (74 MPH...119 KM/H)... FOR LOCATIONS AND TIME PERIODS DURING THE NEXT 5 DAYS PROBABILITIES FOR LOCATIONS ARE GIVEN AS OP(CP) WHERE OP IS THE PROBABILITY OF THE EVENT BEGINNING DURING AN INDIVIDUAL TIME PERIOD (ONSET PROBABILITY) (CP) IS THE PROBABILITY OF THE EVENT OCCURRING BETWEEN 06Z WED AND THE FORECAST HOUR (CUMULATIVE PROBABILITY) PROBABILITIES ARE GIVEN IN PERCENT X INDICATES PROBABILITIES LESS THAN 1 PERCENT PROBABILITIES FOR 34 KT AND 50 KT ARE SHOWN AT A GIVEN LOCATION WHEN THE 5-DAY CUMULATIVE PROBABILITY IS AT LEAST 3 PERCENT. PROBABILITIES FOR 34...50...64 KT SHOWN WHEN THE 5-DAY 64-KT CUMULATIVE PROBABILITY IS AT LEAST 1 PERCENT. - - - - WIND SPEED PROBABILITIES FOR SELECTED LOCATIONS - - - - FROM FROM FROM FROM FROM FROM FROM TIME 06Z WED 18Z WED 06Z THU 18Z THU 06Z FRI 06Z SAT 06Z SUN PERIODS TO TO TO TO TO TO TO 18Z WED 06Z THU 18Z THU 06Z FRI 06Z SAT 06Z SUN 06Z MON FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT 20N 135W 34 1 6( 7) X( 7) X( 7) X( 7) X( 7) X( 7) 20N 140W 34 X X( X) 2( 2) 6( 8) X( 8) X( 8) X( 8) $$ FORECASTER KELLY

Issued at 1100 PM HST Tue Aug 27 2024 000 WTPZ33 KNHC 280833 TCPEP3 BULLETIN Tropical Storm Hector Advisory Number 11 NWS National Hurricane Center Miami FL EP082024 1100 PM HST Tue Aug 27 2024 ...HECTOR FORECAST TO WEAKEN AS IT MOVES WEST-NORTHWESTWARD... SUMMARY OF 1100 PM HST...0900 UTC...INFORMATION ----------------------------------------------- LOCATION...18.4N 132.0W ABOUT 1460 MI...2350 KM W OF THE SOUTHERN TIP OF BAJA CALIFORNIA MAXIMUM SUSTAINED WINDS...50 MPH...85 KM/H PRESENT MOVEMENT...WNW OR 285 DEGREES AT 12 MPH...19 KM/H MINIMUM CENTRAL PRESSURE...1002 MB...29.59 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 1100 PM HST (0900 UTC), the center of Tropical Storm Hector was located near latitude 18.4 North, longitude 132.0 West. Hector is moving toward the west-northwest near 12 mph (19 km/h) and this motion with a turn more westward is anticipated over the next few days. Maximum sustained winds are near 50 mph (85 km/h) with higher gusts. Gradual weakening is anticipated during the next few days and Hector is forecast to become a remnant low on Thursday. Tropical-storm-force winds extend outward up to 70 miles (110 km) from the center. The estimated minimum central pressure is 1002 mb (29.59 inches). HAZARDS AFFECTING LAND ---------------------- None NEXT ADVISORY ------------- Next complete advisory at 500 AM HST. $$ Forecaster Kelly

...HECTOR FORECAST TO WEAKEN AS IT MOVES WEST-NORTHWESTWARD... As of 11:00 PM HST Tue Aug 27 the center of Hector was located near 18.4, -132.0 with movement WNW at 12 mph. The minimum central pressure was 1002 mb with maximum sustained winds of about 50 mph.