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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

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Fri Aug 09 2024 Valid 111200Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe-thunderstorm potential appears too low and uncertain for an unconditional outlook at this time, though some threat may develop over parts of the south-central Plains region. ...Synopsis... In mid/upper levels, the southeastern Canadian cyclone discussed in the day-2 outlook will move slowly eastward over central/southern QC and the St. Lawrence Valley, perhaps with a southward repositioning of its net center as a strong shortwave trough is absorbed through its southern semicircle. Farther south, a combination of monsoonal- origin and convectively generated vorticity lobes should enter the southern fringes of the associated cyclonic flow aloft, moving from the central Plains around the start of the period (11/12Z) to the Ohio Valley central Appalachians region by 12/12Z. Strong ridging will persist over much of TX, with a synoptic ridge extending northwestward over the Four Corners and northern Rockies. As that occurs, the East Coast cold front should move farther southward, but slowly, extending across parts of SC to a frontal- wave low over central GA around 12/00Z, becoming quasistationary over the AL/MS coastal area to southern LA, then a warm front moving northward over central/western OK to southern KS (with some modification possible on the west end by rounds of antecedent convection and associated outflow over the south-central Plains). Widely scattered to scattered thunderstorms will be possible near and south of this boundary over the Southeast and Gulf Coast States. ...South-central Plains to lower Missouri Valley... A conditional severe threat may develop over portions of the south-central Plains -- OK and southern KS in late afternoon or evening near the front. Uncertain influences from outflow/ differential-heating boundaries left by prior convection, as well as the potential for strong capping to keep diurnal development suppressed, render this regime too conditional and spatially uncertain for an outlook this soon, though strong veering with height and increasing moisture/buoyancy should support a favorable CAPE-shear parameter space given initiation. North of the surface front, and nocturnally, elevated convection with hail potential may develop over parts of the lower Missouri Valley. Progs are inconsistent on this, given differences in frontal strength/ orientation and upstream variability in available moisture. ..Edwards.. 08/09/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Fri Aug 09 2024 Valid 111200Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe-thunderstorm potential appears too low and uncertain for an unconditional outlook at this time, though some threat may develop over parts of the south-central Plains region. ...Synopsis... In mid/upper levels, the southeastern Canadian cyclone discussed in the day-2 outlook will move slowly eastward over central/southern QC and the St. Lawrence Valley, perhaps with a southward repositioning of its net center as a strong shortwave trough is absorbed through its southern semicircle. Farther south, a combination of monsoonal- origin and convectively generated vorticity lobes should enter the southern fringes of the associated cyclonic flow aloft, moving from the central Plains around the start of the period (11/12Z) to the Ohio Valley central Appalachians region by 12/12Z. Strong ridging will persist over much of TX, with a synoptic ridge extending northwestward over the Four Corners and northern Rockies. As that occurs, the East Coast cold front should move farther southward, but slowly, extending across parts of SC to a frontal- wave low over central GA around 12/00Z, becoming quasistationary over the AL/MS coastal area to southern LA, then a warm front moving northward over central/western OK to southern KS (with some modification possible on the west end by rounds of antecedent convection and associated outflow over the south-central Plains). Widely scattered to scattered thunderstorms will be possible near and south of this boundary over the Southeast and Gulf Coast States. ...South-central Plains to lower Missouri Valley... A conditional severe threat may develop over portions of the south-central Plains -- OK and southern KS in late afternoon or evening near the front. Uncertain influences from outflow/ differential-heating boundaries left by prior convection, as well as the potential for strong capping to keep diurnal development suppressed, render this regime too conditional and spatially uncertain for an outlook this soon, though strong veering with height and increasing moisture/buoyancy should support a favorable CAPE-shear parameter space given initiation. North of the surface front, and nocturnally, elevated convection with hail potential may develop over parts of the lower Missouri Valley. Progs are inconsistent on this, given differences in frontal strength/ orientation and upstream variability in available moisture. ..Edwards.. 08/09/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Fri Aug 09 2024 Valid 111200Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe-thunderstorm potential appears too low and uncertain for an unconditional outlook at this time, though some threat may develop over parts of the south-central Plains region. ...Synopsis... In mid/upper levels, the southeastern Canadian cyclone discussed in the day-2 outlook will move slowly eastward over central/southern QC and the St. Lawrence Valley, perhaps with a southward repositioning of its net center as a strong shortwave trough is absorbed through its southern semicircle. Farther south, a combination of monsoonal- origin and convectively generated vorticity lobes should enter the southern fringes of the associated cyclonic flow aloft, moving from the central Plains around the start of the period (11/12Z) to the Ohio Valley central Appalachians region by 12/12Z. Strong ridging will persist over much of TX, with a synoptic ridge extending northwestward over the Four Corners and northern Rockies. As that occurs, the East Coast cold front should move farther southward, but slowly, extending across parts of SC to a frontal- wave low over central GA around 12/00Z, becoming quasistationary over the AL/MS coastal area to southern LA, then a warm front moving northward over central/western OK to southern KS (with some modification possible on the west end by rounds of antecedent convection and associated outflow over the south-central Plains). Widely scattered to scattered thunderstorms will be possible near and south of this boundary over the Southeast and Gulf Coast States. ...South-central Plains to lower Missouri Valley... A conditional severe threat may develop over portions of the south-central Plains -- OK and southern KS in late afternoon or evening near the front. Uncertain influences from outflow/ differential-heating boundaries left by prior convection, as well as the potential for strong capping to keep diurnal development suppressed, render this regime too conditional and spatially uncertain for an outlook this soon, though strong veering with height and increasing moisture/buoyancy should support a favorable CAPE-shear parameter space given initiation. North of the surface front, and nocturnally, elevated convection with hail potential may develop over parts of the lower Missouri Valley. Progs are inconsistent on this, given differences in frontal strength/ orientation and upstream variability in available moisture. ..Edwards.. 08/09/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Fri Aug 09 2024 Valid 111200Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe-thunderstorm potential appears too low and uncertain for an unconditional outlook at this time, though some threat may develop over parts of the south-central Plains region. ...Synopsis... In mid/upper levels, the southeastern Canadian cyclone discussed in the day-2 outlook will move slowly eastward over central/southern QC and the St. Lawrence Valley, perhaps with a southward repositioning of its net center as a strong shortwave trough is absorbed through its southern semicircle. Farther south, a combination of monsoonal- origin and convectively generated vorticity lobes should enter the southern fringes of the associated cyclonic flow aloft, moving from the central Plains around the start of the period (11/12Z) to the Ohio Valley central Appalachians region by 12/12Z. Strong ridging will persist over much of TX, with a synoptic ridge extending northwestward over the Four Corners and northern Rockies. As that occurs, the East Coast cold front should move farther southward, but slowly, extending across parts of SC to a frontal- wave low over central GA around 12/00Z, becoming quasistationary over the AL/MS coastal area to southern LA, then a warm front moving northward over central/western OK to southern KS (with some modification possible on the west end by rounds of antecedent convection and associated outflow over the south-central Plains). Widely scattered to scattered thunderstorms will be possible near and south of this boundary over the Southeast and Gulf Coast States. ...South-central Plains to lower Missouri Valley... A conditional severe threat may develop over portions of the south-central Plains -- OK and southern KS in late afternoon or evening near the front. Uncertain influences from outflow/ differential-heating boundaries left by prior convection, as well as the potential for strong capping to keep diurnal development suppressed, render this regime too conditional and spatially uncertain for an outlook this soon, though strong veering with height and increasing moisture/buoyancy should support a favorable CAPE-shear parameter space given initiation. North of the surface front, and nocturnally, elevated convection with hail potential may develop over parts of the lower Missouri Valley. Progs are inconsistent on this, given differences in frontal strength/ orientation and upstream variability in available moisture. ..Edwards.. 08/09/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Fri Aug 09 2024 Valid 111200Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe-thunderstorm potential appears too low and uncertain for an unconditional outlook at this time, though some threat may develop over parts of the south-central Plains region. ...Synopsis... In mid/upper levels, the southeastern Canadian cyclone discussed in the day-2 outlook will move slowly eastward over central/southern QC and the St. Lawrence Valley, perhaps with a southward repositioning of its net center as a strong shortwave trough is absorbed through its southern semicircle. Farther south, a combination of monsoonal- origin and convectively generated vorticity lobes should enter the southern fringes of the associated cyclonic flow aloft, moving from the central Plains around the start of the period (11/12Z) to the Ohio Valley central Appalachians region by 12/12Z. Strong ridging will persist over much of TX, with a synoptic ridge extending northwestward over the Four Corners and northern Rockies. As that occurs, the East Coast cold front should move farther southward, but slowly, extending across parts of SC to a frontal- wave low over central GA around 12/00Z, becoming quasistationary over the AL/MS coastal area to southern LA, then a warm front moving northward over central/western OK to southern KS (with some modification possible on the west end by rounds of antecedent convection and associated outflow over the south-central Plains). Widely scattered to scattered thunderstorms will be possible near and south of this boundary over the Southeast and Gulf Coast States. ...South-central Plains to lower Missouri Valley... A conditional severe threat may develop over portions of the south-central Plains -- OK and southern KS in late afternoon or evening near the front. Uncertain influences from outflow/ differential-heating boundaries left by prior convection, as well as the potential for strong capping to keep diurnal development suppressed, render this regime too conditional and spatially uncertain for an outlook this soon, though strong veering with height and increasing moisture/buoyancy should support a favorable CAPE-shear parameter space given initiation. North of the surface front, and nocturnally, elevated convection with hail potential may develop over parts of the lower Missouri Valley. Progs are inconsistent on this, given differences in frontal strength/ orientation and upstream variability in available moisture. ..Edwards.. 08/09/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Fri Aug 09 2024 Valid 111200Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe-thunderstorm potential appears too low and uncertain for an unconditional outlook at this time, though some threat may develop over parts of the south-central Plains region. ...Synopsis... In mid/upper levels, the southeastern Canadian cyclone discussed in the day-2 outlook will move slowly eastward over central/southern QC and the St. Lawrence Valley, perhaps with a southward repositioning of its net center as a strong shortwave trough is absorbed through its southern semicircle. Farther south, a combination of monsoonal- origin and convectively generated vorticity lobes should enter the southern fringes of the associated cyclonic flow aloft, moving from the central Plains around the start of the period (11/12Z) to the Ohio Valley central Appalachians region by 12/12Z. Strong ridging will persist over much of TX, with a synoptic ridge extending northwestward over the Four Corners and northern Rockies. As that occurs, the East Coast cold front should move farther southward, but slowly, extending across parts of SC to a frontal- wave low over central GA around 12/00Z, becoming quasistationary over the AL/MS coastal area to southern LA, then a warm front moving northward over central/western OK to southern KS (with some modification possible on the west end by rounds of antecedent convection and associated outflow over the south-central Plains). Widely scattered to scattered thunderstorms will be possible near and south of this boundary over the Southeast and Gulf Coast States. ...South-central Plains to lower Missouri Valley... A conditional severe threat may develop over portions of the south-central Plains -- OK and southern KS in late afternoon or evening near the front. Uncertain influences from outflow/ differential-heating boundaries left by prior convection, as well as the potential for strong capping to keep diurnal development suppressed, render this regime too conditional and spatially uncertain for an outlook this soon, though strong veering with height and increasing moisture/buoyancy should support a favorable CAPE-shear parameter space given initiation. North of the surface front, and nocturnally, elevated convection with hail potential may develop over parts of the lower Missouri Valley. Progs are inconsistent on this, given differences in frontal strength/ orientation and upstream variability in available moisture. ..Edwards.. 08/09/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Fri Aug 09 2024 Valid 111200Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe-thunderstorm potential appears too low and uncertain for an unconditional outlook at this time, though some threat may develop over parts of the south-central Plains region. ...Synopsis... In mid/upper levels, the southeastern Canadian cyclone discussed in the day-2 outlook will move slowly eastward over central/southern QC and the St. Lawrence Valley, perhaps with a southward repositioning of its net center as a strong shortwave trough is absorbed through its southern semicircle. Farther south, a combination of monsoonal- origin and convectively generated vorticity lobes should enter the southern fringes of the associated cyclonic flow aloft, moving from the central Plains around the start of the period (11/12Z) to the Ohio Valley central Appalachians region by 12/12Z. Strong ridging will persist over much of TX, with a synoptic ridge extending northwestward over the Four Corners and northern Rockies. As that occurs, the East Coast cold front should move farther southward, but slowly, extending across parts of SC to a frontal- wave low over central GA around 12/00Z, becoming quasistationary over the AL/MS coastal area to southern LA, then a warm front moving northward over central/western OK to southern KS (with some modification possible on the west end by rounds of antecedent convection and associated outflow over the south-central Plains). Widely scattered to scattered thunderstorms will be possible near and south of this boundary over the Southeast and Gulf Coast States. ...South-central Plains to lower Missouri Valley... A conditional severe threat may develop over portions of the south-central Plains -- OK and southern KS in late afternoon or evening near the front. Uncertain influences from outflow/ differential-heating boundaries left by prior convection, as well as the potential for strong capping to keep diurnal development suppressed, render this regime too conditional and spatially uncertain for an outlook this soon, though strong veering with height and increasing moisture/buoyancy should support a favorable CAPE-shear parameter space given initiation. North of the surface front, and nocturnally, elevated convection with hail potential may develop over parts of the lower Missouri Valley. Progs are inconsistent on this, given differences in frontal strength/ orientation and upstream variability in available moisture. ..Edwards.. 08/09/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Fri Aug 09 2024 Valid 111200Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe-thunderstorm potential appears too low and uncertain for an unconditional outlook at this time, though some threat may develop over parts of the south-central Plains region. ...Synopsis... In mid/upper levels, the southeastern Canadian cyclone discussed in the day-2 outlook will move slowly eastward over central/southern QC and the St. Lawrence Valley, perhaps with a southward repositioning of its net center as a strong shortwave trough is absorbed through its southern semicircle. Farther south, a combination of monsoonal- origin and convectively generated vorticity lobes should enter the southern fringes of the associated cyclonic flow aloft, moving from the central Plains around the start of the period (11/12Z) to the Ohio Valley central Appalachians region by 12/12Z. Strong ridging will persist over much of TX, with a synoptic ridge extending northwestward over the Four Corners and northern Rockies. As that occurs, the East Coast cold front should move farther southward, but slowly, extending across parts of SC to a frontal- wave low over central GA around 12/00Z, becoming quasistationary over the AL/MS coastal area to southern LA, then a warm front moving northward over central/western OK to southern KS (with some modification possible on the west end by rounds of antecedent convection and associated outflow over the south-central Plains). Widely scattered to scattered thunderstorms will be possible near and south of this boundary over the Southeast and Gulf Coast States. ...South-central Plains to lower Missouri Valley... A conditional severe threat may develop over portions of the south-central Plains -- OK and southern KS in late afternoon or evening near the front. Uncertain influences from outflow/ differential-heating boundaries left by prior convection, as well as the potential for strong capping to keep diurnal development suppressed, render this regime too conditional and spatially uncertain for an outlook this soon, though strong veering with height and increasing moisture/buoyancy should support a favorable CAPE-shear parameter space given initiation. North of the surface front, and nocturnally, elevated convection with hail potential may develop over parts of the lower Missouri Valley. Progs are inconsistent on this, given differences in frontal strength/ orientation and upstream variability in available moisture. ..Edwards.. 08/09/2024 Read more

WW 0615 Status Updates
STATUS REPORT ON WW 615 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 10 SSW OAJ TO 30 E GSB TO 35 ENE RWI TO 30 ESE RZZ TO 40 S RIC TO 10 NE RIC TO 25 N RIC TO 35 NNW RIC TO 20 SSE SHD. ..JEWELL..08/09/24 ATTN...WFO...LWX...MHX...AKQ...RNK...RAH... STATUS REPORT FOR WT 615 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS DCC001-090840- DC . DISTRICT OF COLUMBIA COUNTIES INCLUDED ARE DISTRICT OF COLUMBIA MDC003-005-009-013-015-017-021-025-027-031-033-037-043-510- 090840- MD . MARYLAND COUNTIES INCLUDED ARE ANNE ARUNDEL BALTIMORE CALVERT CARROLL CECIL CHARLES FREDERICK HARFORD HOWARD MONTGOMERY PRINCE GEORGES ST. MARYS WASHINGTON MARYLAND INDEPENDENT CITIES INCLUDED ARE BALTIMORE CITY Read more

WW 0615 Status Updates
STATUS REPORT ON WW 615 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 10 SSW OAJ TO 30 E GSB TO 35 ENE RWI TO 30 ESE RZZ TO 40 S RIC TO 10 NE RIC TO 25 N RIC TO 35 NNW RIC TO 20 SSE SHD. ..JEWELL..08/09/24 ATTN...WFO...LWX...MHX...AKQ...RNK...RAH... STATUS REPORT FOR WT 615 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS DCC001-090840- DC . DISTRICT OF COLUMBIA COUNTIES INCLUDED ARE DISTRICT OF COLUMBIA MDC003-005-009-013-015-017-021-025-027-031-033-037-043-510- 090840- MD . MARYLAND COUNTIES INCLUDED ARE ANNE ARUNDEL BALTIMORE CALVERT CARROLL CECIL CHARLES FREDERICK HARFORD HOWARD MONTGOMERY PRINCE GEORGES ST. MARYS WASHINGTON MARYLAND INDEPENDENT CITIES INCLUDED ARE BALTIMORE CITY Read more

WW 0615 Status Updates
STATUS REPORT ON WW 615 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 10 SSW OAJ TO 30 E GSB TO 35 ENE RWI TO 30 ESE RZZ TO 40 S RIC TO 10 NE RIC TO 25 N RIC TO 35 NNW RIC TO 20 SSE SHD. ..JEWELL..08/09/24 ATTN...WFO...LWX...MHX...AKQ...RNK...RAH... STATUS REPORT FOR WT 615 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS DCC001-090840- DC . DISTRICT OF COLUMBIA COUNTIES INCLUDED ARE DISTRICT OF COLUMBIA MDC003-005-009-013-015-017-021-025-027-031-033-037-043-510- 090840- MD . MARYLAND COUNTIES INCLUDED ARE ANNE ARUNDEL BALTIMORE CALVERT CARROLL CECIL CHARLES FREDERICK HARFORD HOWARD MONTGOMERY PRINCE GEORGES ST. MARYS WASHINGTON MARYLAND INDEPENDENT CITIES INCLUDED ARE BALTIMORE CITY Read more

WW 0615 Status Updates
STATUS REPORT ON WW 615 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 10 SSW OAJ TO 30 E GSB TO 35 ENE RWI TO 30 ESE RZZ TO 40 S RIC TO 10 NE RIC TO 25 N RIC TO 35 NNW RIC TO 20 SSE SHD. ..JEWELL..08/09/24 ATTN...WFO...LWX...MHX...AKQ...RNK...RAH... STATUS REPORT FOR WT 615 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS DCC001-090840- DC . DISTRICT OF COLUMBIA COUNTIES INCLUDED ARE DISTRICT OF COLUMBIA MDC003-005-009-013-015-017-021-025-027-031-033-037-043-510- 090840- MD . MARYLAND COUNTIES INCLUDED ARE ANNE ARUNDEL BALTIMORE CALVERT CARROLL CECIL CHARLES FREDERICK HARFORD HOWARD MONTGOMERY PRINCE GEORGES ST. MARYS WASHINGTON MARYLAND INDEPENDENT CITIES INCLUDED ARE BALTIMORE CITY Read more

WW 615 TORNADO DC MD NC VA WV CW 082235Z - 091100Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 615 NWS Storm Prediction Center Norman OK 635 PM EDT Thu Aug 8 2024 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of District Of Columbia Maryland Eastern North Carolina Central and eastern Virginia The eastern West Virginia Panhandle Coastal Waters * Effective this Thursday night and Friday morning from 635 PM until 700 AM EDT. * Primary threats include... A few tornadoes possible SUMMARY...Convective bands with embedded supercells and the potential for a few tornadoes will persist overnight and spread northward from North Carolina into Virginia/Maryland with the remnants of tropical cyclone Debby. The tornado watch area is approximately along and 70 statute miles east and west of a line from 30 miles east northeast of Martinsburg WV to 35 miles east of Goldsboro NC. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU5). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Tornado Watch means conditions are favorable for tornadoes and severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. && OTHER WATCH INFORMATION...This tornado watch replaces tornado watch number 614. Watch number 614 will not be in effect after 635 PM EDT. AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 0.5 inches. Extreme turbulence and surface wind gusts to 50 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 17035. ...Thompson Read more

WW 0615 Status Updates
STATUS REPORT ON WW 615 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 10 SW OAJ TO 30 ESE RWI TO 20 SE RZZ TO 5 N RZZ TO 20 NW AVC TO 35 NW AVC TO 10 S SHD. ..JEWELL..08/09/24 ATTN...WFO...LWX...MHX...AKQ...RNK...RAH... STATUS REPORT FOR WT 615 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS DCC001-090740- DC . DISTRICT OF COLUMBIA COUNTIES INCLUDED ARE DISTRICT OF COLUMBIA MDC003-005-009-013-015-017-021-025-027-031-033-037-043-510- 090740- MD . MARYLAND COUNTIES INCLUDED ARE ANNE ARUNDEL BALTIMORE CALVERT CARROLL CECIL CHARLES FREDERICK HARFORD HOWARD MONTGOMERY PRINCE GEORGES ST. MARYS WASHINGTON MARYLAND INDEPENDENT CITIES INCLUDED ARE BALTIMORE CITY Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1256 AM CDT Fri Aug 09 2024 Valid 101200Z - 111200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE SOUTH-CENTRAL HIGH PLAINS... ...SUMMARY... Isolated severe thunderstorms (gusts, perhaps hail) are possible during the afternoon into early evening over parts of the south- central High Plains. ...Synopsis... In mid/upper levels, the persistent Southwestern ridging that is being weakened by a monsoonal trough will redevelop a closed high over central/west TX through day 2. A height weakness will remain from parts of AZ across the Four Corners to southern CO, through which small, collectively generated/enhanced vorticity lobes should move slowly. Farther north, a somewhat blocky, slow-moving pattern will be characterized by gradual breakdown of a Rex configuration now over western Canada, with an undercutting stream of nearly zonal flow across the Northwest and north-central Plains. This will converge into a belt of cyclonic flow around a substantial mid/upper cyclone -- now centered over the northern Lake Superior/Lakehead region of northern ON. Through the day-2 period, the low should pivot across northeastern ON to western QC south and southeast of James Bay, as a series of small shortwaves rotate through the cyclone's western/southern sectors. In response to these developments, the rapidly decaying, open-wave remnants of Debby should be absorbed into a baroclinic zone and ejecting away from the Northeast by the start of this period, leaving behind a cold front from central New England southwestward down the Piedmont in NC/SC to central GA and coastal LA. This boundary should become a diffuse warm front from LA northwestward across southeast/west-central TX to east-central NM. By 00Z, the front should extend from the near the Hampton Roads area southwestward over southern GA and the western FL Panhandle, arching northwestward from southern LA across the TX Panhandle and into a low over southeastern CO/western OK Panhandle region. ...Central to south-central High Plains... Widely scattered to scattered thunderstorms are possible in a corridor extending southeastward from near the low, along the front, and off the nearby Raton Mesa and Palmer Divide. Mid/upper support may be present in the form of a small perturbation or two migrating from the Four Corners region. Activity should develop during mid/late afternoon as boundary-layer convergence near the low and heating of elevated terrain combine to remove MLCINH, along the northwestern fringe of a plume of returning low-level moisture along and south of the warm front. Forecast soundings indicate surface dewpoints in the mid 50s to low 60s and a deep troposphere will support MLCAPE in the 1500-2500 J/kg range, atop a well-mixed subcloud layer. This area will have generally weak low-level speeds, but strong veering of winds with height under the southern fringe of favorable mid/upper winds, with 25-40-kt effective-shear magnitudes. As such, organized multicells and perhaps brief supercells are possible, with isolated severe gusts and hail. Farther north/northwest across northeastern CO and central/eastern WY, an isolated, high-based, strong-severe thunderstorm cannot be ruled out -- moving out of higher terrain of the Bighorns, Laramie Range or northern Front Range/Cheyenne Ridge region -- beneath stronger mid/upper flow and greater deep shear. However, lack of more-robust moisture, and convective-coverage uncertainty, preclude an unconditional outlook at this time. ..Edwards.. 08/09/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1256 AM CDT Fri Aug 09 2024 Valid 101200Z - 111200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE SOUTH-CENTRAL HIGH PLAINS... ...SUMMARY... Isolated severe thunderstorms (gusts, perhaps hail) are possible during the afternoon into early evening over parts of the south- central High Plains. ...Synopsis... In mid/upper levels, the persistent Southwestern ridging that is being weakened by a monsoonal trough will redevelop a closed high over central/west TX through day 2. A height weakness will remain from parts of AZ across the Four Corners to southern CO, through which small, collectively generated/enhanced vorticity lobes should move slowly. Farther north, a somewhat blocky, slow-moving pattern will be characterized by gradual breakdown of a Rex configuration now over western Canada, with an undercutting stream of nearly zonal flow across the Northwest and north-central Plains. This will converge into a belt of cyclonic flow around a substantial mid/upper cyclone -- now centered over the northern Lake Superior/Lakehead region of northern ON. Through the day-2 period, the low should pivot across northeastern ON to western QC south and southeast of James Bay, as a series of small shortwaves rotate through the cyclone's western/southern sectors. In response to these developments, the rapidly decaying, open-wave remnants of Debby should be absorbed into a baroclinic zone and ejecting away from the Northeast by the start of this period, leaving behind a cold front from central New England southwestward down the Piedmont in NC/SC to central GA and coastal LA. This boundary should become a diffuse warm front from LA northwestward across southeast/west-central TX to east-central NM. By 00Z, the front should extend from the near the Hampton Roads area southwestward over southern GA and the western FL Panhandle, arching northwestward from southern LA across the TX Panhandle and into a low over southeastern CO/western OK Panhandle region. ...Central to south-central High Plains... Widely scattered to scattered thunderstorms are possible in a corridor extending southeastward from near the low, along the front, and off the nearby Raton Mesa and Palmer Divide. Mid/upper support may be present in the form of a small perturbation or two migrating from the Four Corners region. Activity should develop during mid/late afternoon as boundary-layer convergence near the low and heating of elevated terrain combine to remove MLCINH, along the northwestern fringe of a plume of returning low-level moisture along and south of the warm front. Forecast soundings indicate surface dewpoints in the mid 50s to low 60s and a deep troposphere will support MLCAPE in the 1500-2500 J/kg range, atop a well-mixed subcloud layer. This area will have generally weak low-level speeds, but strong veering of winds with height under the southern fringe of favorable mid/upper winds, with 25-40-kt effective-shear magnitudes. As such, organized multicells and perhaps brief supercells are possible, with isolated severe gusts and hail. Farther north/northwest across northeastern CO and central/eastern WY, an isolated, high-based, strong-severe thunderstorm cannot be ruled out -- moving out of higher terrain of the Bighorns, Laramie Range or northern Front Range/Cheyenne Ridge region -- beneath stronger mid/upper flow and greater deep shear. However, lack of more-robust moisture, and convective-coverage uncertainty, preclude an unconditional outlook at this time. ..Edwards.. 08/09/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1256 AM CDT Fri Aug 09 2024 Valid 101200Z - 111200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE SOUTH-CENTRAL HIGH PLAINS... ...SUMMARY... Isolated severe thunderstorms (gusts, perhaps hail) are possible during the afternoon into early evening over parts of the south- central High Plains. ...Synopsis... In mid/upper levels, the persistent Southwestern ridging that is being weakened by a monsoonal trough will redevelop a closed high over central/west TX through day 2. A height weakness will remain from parts of AZ across the Four Corners to southern CO, through which small, collectively generated/enhanced vorticity lobes should move slowly. Farther north, a somewhat blocky, slow-moving pattern will be characterized by gradual breakdown of a Rex configuration now over western Canada, with an undercutting stream of nearly zonal flow across the Northwest and north-central Plains. This will converge into a belt of cyclonic flow around a substantial mid/upper cyclone -- now centered over the northern Lake Superior/Lakehead region of northern ON. Through the day-2 period, the low should pivot across northeastern ON to western QC south and southeast of James Bay, as a series of small shortwaves rotate through the cyclone's western/southern sectors. In response to these developments, the rapidly decaying, open-wave remnants of Debby should be absorbed into a baroclinic zone and ejecting away from the Northeast by the start of this period, leaving behind a cold front from central New England southwestward down the Piedmont in NC/SC to central GA and coastal LA. This boundary should become a diffuse warm front from LA northwestward across southeast/west-central TX to east-central NM. By 00Z, the front should extend from the near the Hampton Roads area southwestward over southern GA and the western FL Panhandle, arching northwestward from southern LA across the TX Panhandle and into a low over southeastern CO/western OK Panhandle region. ...Central to south-central High Plains... Widely scattered to scattered thunderstorms are possible in a corridor extending southeastward from near the low, along the front, and off the nearby Raton Mesa and Palmer Divide. Mid/upper support may be present in the form of a small perturbation or two migrating from the Four Corners region. Activity should develop during mid/late afternoon as boundary-layer convergence near the low and heating of elevated terrain combine to remove MLCINH, along the northwestern fringe of a plume of returning low-level moisture along and south of the warm front. Forecast soundings indicate surface dewpoints in the mid 50s to low 60s and a deep troposphere will support MLCAPE in the 1500-2500 J/kg range, atop a well-mixed subcloud layer. This area will have generally weak low-level speeds, but strong veering of winds with height under the southern fringe of favorable mid/upper winds, with 25-40-kt effective-shear magnitudes. As such, organized multicells and perhaps brief supercells are possible, with isolated severe gusts and hail. Farther north/northwest across northeastern CO and central/eastern WY, an isolated, high-based, strong-severe thunderstorm cannot be ruled out -- moving out of higher terrain of the Bighorns, Laramie Range or northern Front Range/Cheyenne Ridge region -- beneath stronger mid/upper flow and greater deep shear. However, lack of more-robust moisture, and convective-coverage uncertainty, preclude an unconditional outlook at this time. ..Edwards.. 08/09/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1256 AM CDT Fri Aug 09 2024 Valid 101200Z - 111200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE SOUTH-CENTRAL HIGH PLAINS... ...SUMMARY... Isolated severe thunderstorms (gusts, perhaps hail) are possible during the afternoon into early evening over parts of the south- central High Plains. ...Synopsis... In mid/upper levels, the persistent Southwestern ridging that is being weakened by a monsoonal trough will redevelop a closed high over central/west TX through day 2. A height weakness will remain from parts of AZ across the Four Corners to southern CO, through which small, collectively generated/enhanced vorticity lobes should move slowly. Farther north, a somewhat blocky, slow-moving pattern will be characterized by gradual breakdown of a Rex configuration now over western Canada, with an undercutting stream of nearly zonal flow across the Northwest and north-central Plains. This will converge into a belt of cyclonic flow around a substantial mid/upper cyclone -- now centered over the northern Lake Superior/Lakehead region of northern ON. Through the day-2 period, the low should pivot across northeastern ON to western QC south and southeast of James Bay, as a series of small shortwaves rotate through the cyclone's western/southern sectors. In response to these developments, the rapidly decaying, open-wave remnants of Debby should be absorbed into a baroclinic zone and ejecting away from the Northeast by the start of this period, leaving behind a cold front from central New England southwestward down the Piedmont in NC/SC to central GA and coastal LA. This boundary should become a diffuse warm front from LA northwestward across southeast/west-central TX to east-central NM. By 00Z, the front should extend from the near the Hampton Roads area southwestward over southern GA and the western FL Panhandle, arching northwestward from southern LA across the TX Panhandle and into a low over southeastern CO/western OK Panhandle region. ...Central to south-central High Plains... Widely scattered to scattered thunderstorms are possible in a corridor extending southeastward from near the low, along the front, and off the nearby Raton Mesa and Palmer Divide. Mid/upper support may be present in the form of a small perturbation or two migrating from the Four Corners region. Activity should develop during mid/late afternoon as boundary-layer convergence near the low and heating of elevated terrain combine to remove MLCINH, along the northwestern fringe of a plume of returning low-level moisture along and south of the warm front. Forecast soundings indicate surface dewpoints in the mid 50s to low 60s and a deep troposphere will support MLCAPE in the 1500-2500 J/kg range, atop a well-mixed subcloud layer. This area will have generally weak low-level speeds, but strong veering of winds with height under the southern fringe of favorable mid/upper winds, with 25-40-kt effective-shear magnitudes. As such, organized multicells and perhaps brief supercells are possible, with isolated severe gusts and hail. Farther north/northwest across northeastern CO and central/eastern WY, an isolated, high-based, strong-severe thunderstorm cannot be ruled out -- moving out of higher terrain of the Bighorns, Laramie Range or northern Front Range/Cheyenne Ridge region -- beneath stronger mid/upper flow and greater deep shear. However, lack of more-robust moisture, and convective-coverage uncertainty, preclude an unconditional outlook at this time. ..Edwards.. 08/09/2024 Read more