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SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0736 AM CDT Fri Aug 09 2024 Valid 091300Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE MID-ATLANTIC STATES INTO EASTERN NEW YORK... ...SUMMARY... A tornado threat is expected today from the Mid-Atlantic states northward into eastern New York. A few strong wind gusts will also be possible across parts of the Northeast, and in parts of the southern Plains. ...Mid-Atlantic states into the Northeast... The remnants of Debby will continue to move north-northeast and accelerate reaching the St. Lawrence Valley late this evening as a mid-level speed max over the Midwest quickly moves through the southern and Lower Great Lakes regions. A warm front will advance northward into central NY and New England later today as a southerly 850-mb speed max shifts northward. South of the boundary, a very moisture-rich airmass (mid 70s deg F surface dewpoints) and some modest heating will contribute to weak to moderate destabilization. The 12 UTC IAD raob showed 250 J/kg MLCAPE and 36 kt of 0-0.5 km shear. Enlarged hodographs especially in the vicinity of the surface frontal zone will aid in storm-scale rotation with any robust updraft. The risk for a few tornadoes will likely focus initially over the Mid-Atlantic states and PA this morning before shifting northward towards early afternoon. A wind-damage threat may also develop today with the stronger linear structures and supercells. This activity is expected to eventually affect parts of western New England by mid to late afternoon and into the early evening before diminishing. ...East-central Texas... A moist airmass will be in place today across parts of the Texas Coastal Plains northward into the Texas Hill Country. As surface temperatures warm, moderate instability will develop across parts of central and east Texas. Model forecasts indicate widely scattered to scattered storms will favor this region later this afternoon into the early evening. The expected moderate instability combined with steep low-level lapse rates could be sufficient for a few marginally severe wind gusts. ...Southern High Plains... A large area of mid to upper-level high pressure will remain over the southern Plains today. At the surface, an axis of maximized low-level moisture will be in place across parts of west Texas and eastern New Mexico. As surface temperatures warm, moderate instability will likely develop along this corridor. Convection that initiates in the higher terrain of northern New Mexico is expected to move southeastward along the northern edge of this instability corridor during the afternoon and evening. The stronger cells within this cluster may be associated with marginally severe wind gusts. ..Smith/Jewell.. 08/09/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0736 AM CDT Fri Aug 09 2024 Valid 091300Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE MID-ATLANTIC STATES INTO EASTERN NEW YORK... ...SUMMARY... A tornado threat is expected today from the Mid-Atlantic states northward into eastern New York. A few strong wind gusts will also be possible across parts of the Northeast, and in parts of the southern Plains. ...Mid-Atlantic states into the Northeast... The remnants of Debby will continue to move north-northeast and accelerate reaching the St. Lawrence Valley late this evening as a mid-level speed max over the Midwest quickly moves through the southern and Lower Great Lakes regions. A warm front will advance northward into central NY and New England later today as a southerly 850-mb speed max shifts northward. South of the boundary, a very moisture-rich airmass (mid 70s deg F surface dewpoints) and some modest heating will contribute to weak to moderate destabilization. The 12 UTC IAD raob showed 250 J/kg MLCAPE and 36 kt of 0-0.5 km shear. Enlarged hodographs especially in the vicinity of the surface frontal zone will aid in storm-scale rotation with any robust updraft. The risk for a few tornadoes will likely focus initially over the Mid-Atlantic states and PA this morning before shifting northward towards early afternoon. A wind-damage threat may also develop today with the stronger linear structures and supercells. This activity is expected to eventually affect parts of western New England by mid to late afternoon and into the early evening before diminishing. ...East-central Texas... A moist airmass will be in place today across parts of the Texas Coastal Plains northward into the Texas Hill Country. As surface temperatures warm, moderate instability will develop across parts of central and east Texas. Model forecasts indicate widely scattered to scattered storms will favor this region later this afternoon into the early evening. The expected moderate instability combined with steep low-level lapse rates could be sufficient for a few marginally severe wind gusts. ...Southern High Plains... A large area of mid to upper-level high pressure will remain over the southern Plains today. At the surface, an axis of maximized low-level moisture will be in place across parts of west Texas and eastern New Mexico. As surface temperatures warm, moderate instability will likely develop along this corridor. Convection that initiates in the higher terrain of northern New Mexico is expected to move southeastward along the northern edge of this instability corridor during the afternoon and evening. The stronger cells within this cluster may be associated with marginally severe wind gusts. ..Smith/Jewell.. 08/09/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0736 AM CDT Fri Aug 09 2024 Valid 091300Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE MID-ATLANTIC STATES INTO EASTERN NEW YORK... ...SUMMARY... A tornado threat is expected today from the Mid-Atlantic states northward into eastern New York. A few strong wind gusts will also be possible across parts of the Northeast, and in parts of the southern Plains. ...Mid-Atlantic states into the Northeast... The remnants of Debby will continue to move north-northeast and accelerate reaching the St. Lawrence Valley late this evening as a mid-level speed max over the Midwest quickly moves through the southern and Lower Great Lakes regions. A warm front will advance northward into central NY and New England later today as a southerly 850-mb speed max shifts northward. South of the boundary, a very moisture-rich airmass (mid 70s deg F surface dewpoints) and some modest heating will contribute to weak to moderate destabilization. The 12 UTC IAD raob showed 250 J/kg MLCAPE and 36 kt of 0-0.5 km shear. Enlarged hodographs especially in the vicinity of the surface frontal zone will aid in storm-scale rotation with any robust updraft. The risk for a few tornadoes will likely focus initially over the Mid-Atlantic states and PA this morning before shifting northward towards early afternoon. A wind-damage threat may also develop today with the stronger linear structures and supercells. This activity is expected to eventually affect parts of western New England by mid to late afternoon and into the early evening before diminishing. ...East-central Texas... A moist airmass will be in place today across parts of the Texas Coastal Plains northward into the Texas Hill Country. As surface temperatures warm, moderate instability will develop across parts of central and east Texas. Model forecasts indicate widely scattered to scattered storms will favor this region later this afternoon into the early evening. The expected moderate instability combined with steep low-level lapse rates could be sufficient for a few marginally severe wind gusts. ...Southern High Plains... A large area of mid to upper-level high pressure will remain over the southern Plains today. At the surface, an axis of maximized low-level moisture will be in place across parts of west Texas and eastern New Mexico. As surface temperatures warm, moderate instability will likely develop along this corridor. Convection that initiates in the higher terrain of northern New Mexico is expected to move southeastward along the northern edge of this instability corridor during the afternoon and evening. The stronger cells within this cluster may be associated with marginally severe wind gusts. ..Smith/Jewell.. 08/09/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0736 AM CDT Fri Aug 09 2024 Valid 091300Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE MID-ATLANTIC STATES INTO EASTERN NEW YORK... ...SUMMARY... A tornado threat is expected today from the Mid-Atlantic states northward into eastern New York. A few strong wind gusts will also be possible across parts of the Northeast, and in parts of the southern Plains. ...Mid-Atlantic states into the Northeast... The remnants of Debby will continue to move north-northeast and accelerate reaching the St. Lawrence Valley late this evening as a mid-level speed max over the Midwest quickly moves through the southern and Lower Great Lakes regions. A warm front will advance northward into central NY and New England later today as a southerly 850-mb speed max shifts northward. South of the boundary, a very moisture-rich airmass (mid 70s deg F surface dewpoints) and some modest heating will contribute to weak to moderate destabilization. The 12 UTC IAD raob showed 250 J/kg MLCAPE and 36 kt of 0-0.5 km shear. Enlarged hodographs especially in the vicinity of the surface frontal zone will aid in storm-scale rotation with any robust updraft. The risk for a few tornadoes will likely focus initially over the Mid-Atlantic states and PA this morning before shifting northward towards early afternoon. A wind-damage threat may also develop today with the stronger linear structures and supercells. This activity is expected to eventually affect parts of western New England by mid to late afternoon and into the early evening before diminishing. ...East-central Texas... A moist airmass will be in place today across parts of the Texas Coastal Plains northward into the Texas Hill Country. As surface temperatures warm, moderate instability will develop across parts of central and east Texas. Model forecasts indicate widely scattered to scattered storms will favor this region later this afternoon into the early evening. The expected moderate instability combined with steep low-level lapse rates could be sufficient for a few marginally severe wind gusts. ...Southern High Plains... A large area of mid to upper-level high pressure will remain over the southern Plains today. At the surface, an axis of maximized low-level moisture will be in place across parts of west Texas and eastern New Mexico. As surface temperatures warm, moderate instability will likely develop along this corridor. Convection that initiates in the higher terrain of northern New Mexico is expected to move southeastward along the northern edge of this instability corridor during the afternoon and evening. The stronger cells within this cluster may be associated with marginally severe wind gusts. ..Smith/Jewell.. 08/09/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0736 AM CDT Fri Aug 09 2024 Valid 091300Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE MID-ATLANTIC STATES INTO EASTERN NEW YORK... ...SUMMARY... A tornado threat is expected today from the Mid-Atlantic states northward into eastern New York. A few strong wind gusts will also be possible across parts of the Northeast, and in parts of the southern Plains. ...Mid-Atlantic states into the Northeast... The remnants of Debby will continue to move north-northeast and accelerate reaching the St. Lawrence Valley late this evening as a mid-level speed max over the Midwest quickly moves through the southern and Lower Great Lakes regions. A warm front will advance northward into central NY and New England later today as a southerly 850-mb speed max shifts northward. South of the boundary, a very moisture-rich airmass (mid 70s deg F surface dewpoints) and some modest heating will contribute to weak to moderate destabilization. The 12 UTC IAD raob showed 250 J/kg MLCAPE and 36 kt of 0-0.5 km shear. Enlarged hodographs especially in the vicinity of the surface frontal zone will aid in storm-scale rotation with any robust updraft. The risk for a few tornadoes will likely focus initially over the Mid-Atlantic states and PA this morning before shifting northward towards early afternoon. A wind-damage threat may also develop today with the stronger linear structures and supercells. This activity is expected to eventually affect parts of western New England by mid to late afternoon and into the early evening before diminishing. ...East-central Texas... A moist airmass will be in place today across parts of the Texas Coastal Plains northward into the Texas Hill Country. As surface temperatures warm, moderate instability will develop across parts of central and east Texas. Model forecasts indicate widely scattered to scattered storms will favor this region later this afternoon into the early evening. The expected moderate instability combined with steep low-level lapse rates could be sufficient for a few marginally severe wind gusts. ...Southern High Plains... A large area of mid to upper-level high pressure will remain over the southern Plains today. At the surface, an axis of maximized low-level moisture will be in place across parts of west Texas and eastern New Mexico. As surface temperatures warm, moderate instability will likely develop along this corridor. Convection that initiates in the higher terrain of northern New Mexico is expected to move southeastward along the northern edge of this instability corridor during the afternoon and evening. The stronger cells within this cluster may be associated with marginally severe wind gusts. ..Smith/Jewell.. 08/09/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0736 AM CDT Fri Aug 09 2024 Valid 091300Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE MID-ATLANTIC STATES INTO EASTERN NEW YORK... ...SUMMARY... A tornado threat is expected today from the Mid-Atlantic states northward into eastern New York. A few strong wind gusts will also be possible across parts of the Northeast, and in parts of the southern Plains. ...Mid-Atlantic states into the Northeast... The remnants of Debby will continue to move north-northeast and accelerate reaching the St. Lawrence Valley late this evening as a mid-level speed max over the Midwest quickly moves through the southern and Lower Great Lakes regions. A warm front will advance northward into central NY and New England later today as a southerly 850-mb speed max shifts northward. South of the boundary, a very moisture-rich airmass (mid 70s deg F surface dewpoints) and some modest heating will contribute to weak to moderate destabilization. The 12 UTC IAD raob showed 250 J/kg MLCAPE and 36 kt of 0-0.5 km shear. Enlarged hodographs especially in the vicinity of the surface frontal zone will aid in storm-scale rotation with any robust updraft. The risk for a few tornadoes will likely focus initially over the Mid-Atlantic states and PA this morning before shifting northward towards early afternoon. A wind-damage threat may also develop today with the stronger linear structures and supercells. This activity is expected to eventually affect parts of western New England by mid to late afternoon and into the early evening before diminishing. ...East-central Texas... A moist airmass will be in place today across parts of the Texas Coastal Plains northward into the Texas Hill Country. As surface temperatures warm, moderate instability will develop across parts of central and east Texas. Model forecasts indicate widely scattered to scattered storms will favor this region later this afternoon into the early evening. The expected moderate instability combined with steep low-level lapse rates could be sufficient for a few marginally severe wind gusts. ...Southern High Plains... A large area of mid to upper-level high pressure will remain over the southern Plains today. At the surface, an axis of maximized low-level moisture will be in place across parts of west Texas and eastern New Mexico. As surface temperatures warm, moderate instability will likely develop along this corridor. Convection that initiates in the higher terrain of northern New Mexico is expected to move southeastward along the northern edge of this instability corridor during the afternoon and evening. The stronger cells within this cluster may be associated with marginally severe wind gusts. ..Smith/Jewell.. 08/09/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0736 AM CDT Fri Aug 09 2024 Valid 091300Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE MID-ATLANTIC STATES INTO EASTERN NEW YORK... ...SUMMARY... A tornado threat is expected today from the Mid-Atlantic states northward into eastern New York. A few strong wind gusts will also be possible across parts of the Northeast, and in parts of the southern Plains. ...Mid-Atlantic states into the Northeast... The remnants of Debby will continue to move north-northeast and accelerate reaching the St. Lawrence Valley late this evening as a mid-level speed max over the Midwest quickly moves through the southern and Lower Great Lakes regions. A warm front will advance northward into central NY and New England later today as a southerly 850-mb speed max shifts northward. South of the boundary, a very moisture-rich airmass (mid 70s deg F surface dewpoints) and some modest heating will contribute to weak to moderate destabilization. The 12 UTC IAD raob showed 250 J/kg MLCAPE and 36 kt of 0-0.5 km shear. Enlarged hodographs especially in the vicinity of the surface frontal zone will aid in storm-scale rotation with any robust updraft. The risk for a few tornadoes will likely focus initially over the Mid-Atlantic states and PA this morning before shifting northward towards early afternoon. A wind-damage threat may also develop today with the stronger linear structures and supercells. This activity is expected to eventually affect parts of western New England by mid to late afternoon and into the early evening before diminishing. ...East-central Texas... A moist airmass will be in place today across parts of the Texas Coastal Plains northward into the Texas Hill Country. As surface temperatures warm, moderate instability will develop across parts of central and east Texas. Model forecasts indicate widely scattered to scattered storms will favor this region later this afternoon into the early evening. The expected moderate instability combined with steep low-level lapse rates could be sufficient for a few marginally severe wind gusts. ...Southern High Plains... A large area of mid to upper-level high pressure will remain over the southern Plains today. At the surface, an axis of maximized low-level moisture will be in place across parts of west Texas and eastern New Mexico. As surface temperatures warm, moderate instability will likely develop along this corridor. Convection that initiates in the higher terrain of northern New Mexico is expected to move southeastward along the northern edge of this instability corridor during the afternoon and evening. The stronger cells within this cluster may be associated with marginally severe wind gusts. ..Smith/Jewell.. 08/09/2024 Read more

WW 0616 Status Updates
STATUS REPORT ON WW 616 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..JEWELL..08/09/24 ATTN...WFO...LWX...PHI...AKQ...OKX...BGM...CTP... STATUS REPORT FOR WT 616 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS DEC001-003-005-091340- DE . DELAWARE COUNTIES INCLUDED ARE KENT NEW CASTLE SUSSEX DCC001-091340- DC . DISTRICT OF COLUMBIA COUNTIES INCLUDED ARE DISTRICT OF COLUMBIA MDC003-005-009-011-013-015-017-019-021-025-027-029-031-033-035- 037-039-041-045-047-510-091340- MD . MARYLAND COUNTIES INCLUDED ARE ANNE ARUNDEL BALTIMORE CALVERT CAROLINE CARROLL CECIL CHARLES DORCHESTER FREDERICK HARFORD HOWARD KENT Read more

WW 0616 Status Updates
STATUS REPORT ON WW 616 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..JEWELL..08/09/24 ATTN...WFO...LWX...PHI...AKQ...OKX...BGM...CTP... STATUS REPORT FOR WT 616 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS DEC001-003-005-091340- DE . DELAWARE COUNTIES INCLUDED ARE KENT NEW CASTLE SUSSEX DCC001-091340- DC . DISTRICT OF COLUMBIA COUNTIES INCLUDED ARE DISTRICT OF COLUMBIA MDC003-005-009-011-013-015-017-019-021-025-027-029-031-033-035- 037-039-041-045-047-510-091340- MD . MARYLAND COUNTIES INCLUDED ARE ANNE ARUNDEL BALTIMORE CALVERT CAROLINE CARROLL CECIL CHARLES DORCHESTER FREDERICK HARFORD HOWARD KENT Read more

000
ABPZ20 KNHC 091144
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 AM PDT Fri Aug 9 2024

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

South of Southern Mexico:
Disorganized showers and thunderstorms located a couple of hundred
miles south of the coast of southern Mexico are associated with a
tropical wave. Gradual development of this system is possible
during the next several days while it moves west-northwestward at
around 15 mph, parallel to the coast of southern and southwestern
Mexico.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 7 days...low...30 percent.

$$
Forecaster Cangialosi

MD 1872 CONCERNING TORNADO WATCH 615... FOR SOUTHERN PENNSYLVANIA...NORTHERN VIRGINIA...MARYLAND
Mesoscale Discussion 1872 NWS Storm Prediction Center Norman OK 0338 AM CDT Fri Aug 09 2024 Areas affected...southern Pennsylvania...northern Virginia...Maryland Concerning...Tornado Watch 615... Valid 090838Z - 091145Z The severe weather threat for Tornado Watch 615 continues. SUMMARY...The potential remains for brief tornadoes tonight, mainly from northern Virginia into southeast Pennsylvania. DISCUSSION...Surface analysis shows a warm front well into PA, where low-level winds remain backed and are now gusting to 25-30 kt out of the southeast. Theta-e has increased with the passage of the warm front, with mid 70s F dewpoints and temperatures of 77-80 F. Meanwhile, area VWPS indicate that low-level shear remains quite favorable for brief tornadoes, with 0-1 km SRH values over 200 m2/s2. Recent radar trends indicate increasing storms just east of the low, where enhanced lift is interacting with the still warm and unstable air mass. Given current trends, growing showers could become supercells over the next several hours, with a tornado risk. In addition, other convection interacting with the warm front farther north may also attain rotation. As such, the tornado watch continues, and areas just north of the ongoing watch may need to be addressed later this morning as the air mass, and lift, remain favorable. ..Jewell.. 08/09/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PHI...AKQ...CTP...LWX... LAT...LON 38397820 38567829 39137844 39757818 40327756 40887605 40807558 40537528 40177534 39427574 38677609 38307619 37967685 37967722 38287796 38397820 Read more

WW 0616 Status Updates
STATUS FOR WATCH 0616 HAS NOT BEEN ISSUED YET Read more

WW 0616 Status Updates
STATUS FOR WATCH 0616 HAS NOT BEEN ISSUED YET Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0319 AM CDT Fri Aug 09 2024 Valid 121200Z - 171200Z ...DISCUSSION... In mid/upper levels, a zonally elongated anticyclone will build laterally from the southern Plains into the Southwest and Gulf Coast region through much of the day-4-8 period. A general weakness in heights should persist over parts of CA and the lower Colorado River Valley region -- intermittently connected to northern-stream troughing over the Pacific Northwest and western Canada, and to the subtropical easterlies over MX. Low-amplitude mean ridging should build northward across the Rockies to the northern Rockies/northern High Plains region, but based on deterministic GFS/ECMWF and their ensembles, not intense enough to preclude penetration by a series of mostly low-amplitude/low-predictability shortwaves emanating from the Northwest troughing. Downstream, zonal to northwesterly and largely difluent flow will prevail over much of the northern Plains, Midwest, Great Lakes, and Ohio Valley. Even after the southeastern Canada/northeastern CONUS synoptic trough departs the region day-4, the preceding frontal zone will remain well-removed to the south, across the southeastern CONUS to Missouri Valley, as a series of trailing shortwaves reinforce somewhat lower-amplitude troughing in the Great Lakes and Northeast. Especially from about day 5 onward, gradual return of favorable moisture is likely beneath the southwestern rim of the stronger associated flow -- from the north-central High Plains to the lower Missouri and Tennessee Valley regions. This general pattern conditionally supports some MCS potential, evolving from activity forming over the Plains and heading southeastward along or just to the cool side of the sensible baroclinic zone. However, day-to-day shortwave, low-level boundary and MCV predictability is too low to assign unconditional probabilities to any given day. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0319 AM CDT Fri Aug 09 2024 Valid 121200Z - 171200Z ...DISCUSSION... In mid/upper levels, a zonally elongated anticyclone will build laterally from the southern Plains into the Southwest and Gulf Coast region through much of the day-4-8 period. A general weakness in heights should persist over parts of CA and the lower Colorado River Valley region -- intermittently connected to northern-stream troughing over the Pacific Northwest and western Canada, and to the subtropical easterlies over MX. Low-amplitude mean ridging should build northward across the Rockies to the northern Rockies/northern High Plains region, but based on deterministic GFS/ECMWF and their ensembles, not intense enough to preclude penetration by a series of mostly low-amplitude/low-predictability shortwaves emanating from the Northwest troughing. Downstream, zonal to northwesterly and largely difluent flow will prevail over much of the northern Plains, Midwest, Great Lakes, and Ohio Valley. Even after the southeastern Canada/northeastern CONUS synoptic trough departs the region day-4, the preceding frontal zone will remain well-removed to the south, across the southeastern CONUS to Missouri Valley, as a series of trailing shortwaves reinforce somewhat lower-amplitude troughing in the Great Lakes and Northeast. Especially from about day 5 onward, gradual return of favorable moisture is likely beneath the southwestern rim of the stronger associated flow -- from the north-central High Plains to the lower Missouri and Tennessee Valley regions. This general pattern conditionally supports some MCS potential, evolving from activity forming over the Plains and heading southeastward along or just to the cool side of the sensible baroclinic zone. However, day-to-day shortwave, low-level boundary and MCV predictability is too low to assign unconditional probabilities to any given day. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0319 AM CDT Fri Aug 09 2024 Valid 121200Z - 171200Z ...DISCUSSION... In mid/upper levels, a zonally elongated anticyclone will build laterally from the southern Plains into the Southwest and Gulf Coast region through much of the day-4-8 period. A general weakness in heights should persist over parts of CA and the lower Colorado River Valley region -- intermittently connected to northern-stream troughing over the Pacific Northwest and western Canada, and to the subtropical easterlies over MX. Low-amplitude mean ridging should build northward across the Rockies to the northern Rockies/northern High Plains region, but based on deterministic GFS/ECMWF and their ensembles, not intense enough to preclude penetration by a series of mostly low-amplitude/low-predictability shortwaves emanating from the Northwest troughing. Downstream, zonal to northwesterly and largely difluent flow will prevail over much of the northern Plains, Midwest, Great Lakes, and Ohio Valley. Even after the southeastern Canada/northeastern CONUS synoptic trough departs the region day-4, the preceding frontal zone will remain well-removed to the south, across the southeastern CONUS to Missouri Valley, as a series of trailing shortwaves reinforce somewhat lower-amplitude troughing in the Great Lakes and Northeast. Especially from about day 5 onward, gradual return of favorable moisture is likely beneath the southwestern rim of the stronger associated flow -- from the north-central High Plains to the lower Missouri and Tennessee Valley regions. This general pattern conditionally supports some MCS potential, evolving from activity forming over the Plains and heading southeastward along or just to the cool side of the sensible baroclinic zone. However, day-to-day shortwave, low-level boundary and MCV predictability is too low to assign unconditional probabilities to any given day. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0319 AM CDT Fri Aug 09 2024 Valid 121200Z - 171200Z ...DISCUSSION... In mid/upper levels, a zonally elongated anticyclone will build laterally from the southern Plains into the Southwest and Gulf Coast region through much of the day-4-8 period. A general weakness in heights should persist over parts of CA and the lower Colorado River Valley region -- intermittently connected to northern-stream troughing over the Pacific Northwest and western Canada, and to the subtropical easterlies over MX. Low-amplitude mean ridging should build northward across the Rockies to the northern Rockies/northern High Plains region, but based on deterministic GFS/ECMWF and their ensembles, not intense enough to preclude penetration by a series of mostly low-amplitude/low-predictability shortwaves emanating from the Northwest troughing. Downstream, zonal to northwesterly and largely difluent flow will prevail over much of the northern Plains, Midwest, Great Lakes, and Ohio Valley. Even after the southeastern Canada/northeastern CONUS synoptic trough departs the region day-4, the preceding frontal zone will remain well-removed to the south, across the southeastern CONUS to Missouri Valley, as a series of trailing shortwaves reinforce somewhat lower-amplitude troughing in the Great Lakes and Northeast. Especially from about day 5 onward, gradual return of favorable moisture is likely beneath the southwestern rim of the stronger associated flow -- from the north-central High Plains to the lower Missouri and Tennessee Valley regions. This general pattern conditionally supports some MCS potential, evolving from activity forming over the Plains and heading southeastward along or just to the cool side of the sensible baroclinic zone. However, day-to-day shortwave, low-level boundary and MCV predictability is too low to assign unconditional probabilities to any given day. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0319 AM CDT Fri Aug 09 2024 Valid 121200Z - 171200Z ...DISCUSSION... In mid/upper levels, a zonally elongated anticyclone will build laterally from the southern Plains into the Southwest and Gulf Coast region through much of the day-4-8 period. A general weakness in heights should persist over parts of CA and the lower Colorado River Valley region -- intermittently connected to northern-stream troughing over the Pacific Northwest and western Canada, and to the subtropical easterlies over MX. Low-amplitude mean ridging should build northward across the Rockies to the northern Rockies/northern High Plains region, but based on deterministic GFS/ECMWF and their ensembles, not intense enough to preclude penetration by a series of mostly low-amplitude/low-predictability shortwaves emanating from the Northwest troughing. Downstream, zonal to northwesterly and largely difluent flow will prevail over much of the northern Plains, Midwest, Great Lakes, and Ohio Valley. Even after the southeastern Canada/northeastern CONUS synoptic trough departs the region day-4, the preceding frontal zone will remain well-removed to the south, across the southeastern CONUS to Missouri Valley, as a series of trailing shortwaves reinforce somewhat lower-amplitude troughing in the Great Lakes and Northeast. Especially from about day 5 onward, gradual return of favorable moisture is likely beneath the southwestern rim of the stronger associated flow -- from the north-central High Plains to the lower Missouri and Tennessee Valley regions. This general pattern conditionally supports some MCS potential, evolving from activity forming over the Plains and heading southeastward along or just to the cool side of the sensible baroclinic zone. However, day-to-day shortwave, low-level boundary and MCV predictability is too low to assign unconditional probabilities to any given day. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0319 AM CDT Fri Aug 09 2024 Valid 121200Z - 171200Z ...DISCUSSION... In mid/upper levels, a zonally elongated anticyclone will build laterally from the southern Plains into the Southwest and Gulf Coast region through much of the day-4-8 period. A general weakness in heights should persist over parts of CA and the lower Colorado River Valley region -- intermittently connected to northern-stream troughing over the Pacific Northwest and western Canada, and to the subtropical easterlies over MX. Low-amplitude mean ridging should build northward across the Rockies to the northern Rockies/northern High Plains region, but based on deterministic GFS/ECMWF and their ensembles, not intense enough to preclude penetration by a series of mostly low-amplitude/low-predictability shortwaves emanating from the Northwest troughing. Downstream, zonal to northwesterly and largely difluent flow will prevail over much of the northern Plains, Midwest, Great Lakes, and Ohio Valley. Even after the southeastern Canada/northeastern CONUS synoptic trough departs the region day-4, the preceding frontal zone will remain well-removed to the south, across the southeastern CONUS to Missouri Valley, as a series of trailing shortwaves reinforce somewhat lower-amplitude troughing in the Great Lakes and Northeast. Especially from about day 5 onward, gradual return of favorable moisture is likely beneath the southwestern rim of the stronger associated flow -- from the north-central High Plains to the lower Missouri and Tennessee Valley regions. This general pattern conditionally supports some MCS potential, evolving from activity forming over the Plains and heading southeastward along or just to the cool side of the sensible baroclinic zone. However, day-to-day shortwave, low-level boundary and MCV predictability is too low to assign unconditional probabilities to any given day. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0319 AM CDT Fri Aug 09 2024 Valid 121200Z - 171200Z ...DISCUSSION... In mid/upper levels, a zonally elongated anticyclone will build laterally from the southern Plains into the Southwest and Gulf Coast region through much of the day-4-8 period. A general weakness in heights should persist over parts of CA and the lower Colorado River Valley region -- intermittently connected to northern-stream troughing over the Pacific Northwest and western Canada, and to the subtropical easterlies over MX. Low-amplitude mean ridging should build northward across the Rockies to the northern Rockies/northern High Plains region, but based on deterministic GFS/ECMWF and their ensembles, not intense enough to preclude penetration by a series of mostly low-amplitude/low-predictability shortwaves emanating from the Northwest troughing. Downstream, zonal to northwesterly and largely difluent flow will prevail over much of the northern Plains, Midwest, Great Lakes, and Ohio Valley. Even after the southeastern Canada/northeastern CONUS synoptic trough departs the region day-4, the preceding frontal zone will remain well-removed to the south, across the southeastern CONUS to Missouri Valley, as a series of trailing shortwaves reinforce somewhat lower-amplitude troughing in the Great Lakes and Northeast. Especially from about day 5 onward, gradual return of favorable moisture is likely beneath the southwestern rim of the stronger associated flow -- from the north-central High Plains to the lower Missouri and Tennessee Valley regions. This general pattern conditionally supports some MCS potential, evolving from activity forming over the Plains and heading southeastward along or just to the cool side of the sensible baroclinic zone. However, day-to-day shortwave, low-level boundary and MCV predictability is too low to assign unconditional probabilities to any given day. Read more