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SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1126 AM CDT Wed Aug 14 2024 Valid 141630Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS LATE THIS AFTERNOON INTO TONIGHT FOR THE MIDDLE MO VALLEY... ...SUMMARY... Scattered severe thunderstorms capable of all hazards are possible late this afternoon through the evening across portions of the middle Missouri Valley. ...MO Valley area this afternoon through tonight... An MCV over northwest IA will continue eastward today, while clusters of thunderstorms are ongoing this morning from central MO to northern AR within a low-level warm advection regime. Warm advection will slowly weaken through the day, but convective outflow with the central MO storm cluster may result in those storms persisting well into the afternoon while spreading southward. Otherwise, outflow from the morning convection will slowly modify from eastern KS into southeast NE, in advance of a midlevel shortwave trough over the central High Plains, and an associated surface cold front moving southeastward across northwest KS. The cold front and the front/outflow intersection will focus thunderstorm development late this afternoon/evening from central KS to southeast NE/southwest IA, and storms will subsequently spread eastward tonight as one or more storm clusters/MCSs across northern MO/southern IA. Low-level shear/hodograph curvature will be maintained this afternoon within the modifying outflow across the SLGT risk area, where semi-discrete supercells and a couple of tornadoes will be possible. Isolated very large hail (2-2.5 inches in diameter) will also with any persistent supercells, though the severe threat will transition primarily to damaging winds (60-75 mph) by late evening into tonight as storms grow upscale. Farther northwest, a separate clustering of storms is possible in central SD, south of the ongoing convection across southern ND. Surface heating in cloud breaks and weak ascent downstream from an ejecting midlevel trough will help focus thunderstorm development by 21-00z. Low-midlevel vertical shear will not be particularly strong and flow aloft will be strongly backed, which suggests a fairly quick growth into a line segment. Isolated damaging gusts and large hail will be possible for a few hours late this afternoon/evening. ...WY and vicinity this afternoon... An embedded vorticity maximum over southeast ID will progress eastward over WY this afternoon/evening. There will be sufficient low-midlevel moisture and surface heating for high-based thunderstorm development by early afternoon in advance of the vorticity maximum. Given steep low-level lapse rates and modest enhancement to midlevel flow (near 30 kt), strong outflow winds of 50-60 mph will be possible with this convection through the afternoon. ..Thompson/Weinman.. 08/14/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1126 AM CDT Wed Aug 14 2024 Valid 141630Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS LATE THIS AFTERNOON INTO TONIGHT FOR THE MIDDLE MO VALLEY... ...SUMMARY... Scattered severe thunderstorms capable of all hazards are possible late this afternoon through the evening across portions of the middle Missouri Valley. ...MO Valley area this afternoon through tonight... An MCV over northwest IA will continue eastward today, while clusters of thunderstorms are ongoing this morning from central MO to northern AR within a low-level warm advection regime. Warm advection will slowly weaken through the day, but convective outflow with the central MO storm cluster may result in those storms persisting well into the afternoon while spreading southward. Otherwise, outflow from the morning convection will slowly modify from eastern KS into southeast NE, in advance of a midlevel shortwave trough over the central High Plains, and an associated surface cold front moving southeastward across northwest KS. The cold front and the front/outflow intersection will focus thunderstorm development late this afternoon/evening from central KS to southeast NE/southwest IA, and storms will subsequently spread eastward tonight as one or more storm clusters/MCSs across northern MO/southern IA. Low-level shear/hodograph curvature will be maintained this afternoon within the modifying outflow across the SLGT risk area, where semi-discrete supercells and a couple of tornadoes will be possible. Isolated very large hail (2-2.5 inches in diameter) will also with any persistent supercells, though the severe threat will transition primarily to damaging winds (60-75 mph) by late evening into tonight as storms grow upscale. Farther northwest, a separate clustering of storms is possible in central SD, south of the ongoing convection across southern ND. Surface heating in cloud breaks and weak ascent downstream from an ejecting midlevel trough will help focus thunderstorm development by 21-00z. Low-midlevel vertical shear will not be particularly strong and flow aloft will be strongly backed, which suggests a fairly quick growth into a line segment. Isolated damaging gusts and large hail will be possible for a few hours late this afternoon/evening. ...WY and vicinity this afternoon... An embedded vorticity maximum over southeast ID will progress eastward over WY this afternoon/evening. There will be sufficient low-midlevel moisture and surface heating for high-based thunderstorm development by early afternoon in advance of the vorticity maximum. Given steep low-level lapse rates and modest enhancement to midlevel flow (near 30 kt), strong outflow winds of 50-60 mph will be possible with this convection through the afternoon. ..Thompson/Weinman.. 08/14/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1126 AM CDT Wed Aug 14 2024 Valid 141630Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS LATE THIS AFTERNOON INTO TONIGHT FOR THE MIDDLE MO VALLEY... ...SUMMARY... Scattered severe thunderstorms capable of all hazards are possible late this afternoon through the evening across portions of the middle Missouri Valley. ...MO Valley area this afternoon through tonight... An MCV over northwest IA will continue eastward today, while clusters of thunderstorms are ongoing this morning from central MO to northern AR within a low-level warm advection regime. Warm advection will slowly weaken through the day, but convective outflow with the central MO storm cluster may result in those storms persisting well into the afternoon while spreading southward. Otherwise, outflow from the morning convection will slowly modify from eastern KS into southeast NE, in advance of a midlevel shortwave trough over the central High Plains, and an associated surface cold front moving southeastward across northwest KS. The cold front and the front/outflow intersection will focus thunderstorm development late this afternoon/evening from central KS to southeast NE/southwest IA, and storms will subsequently spread eastward tonight as one or more storm clusters/MCSs across northern MO/southern IA. Low-level shear/hodograph curvature will be maintained this afternoon within the modifying outflow across the SLGT risk area, where semi-discrete supercells and a couple of tornadoes will be possible. Isolated very large hail (2-2.5 inches in diameter) will also with any persistent supercells, though the severe threat will transition primarily to damaging winds (60-75 mph) by late evening into tonight as storms grow upscale. Farther northwest, a separate clustering of storms is possible in central SD, south of the ongoing convection across southern ND. Surface heating in cloud breaks and weak ascent downstream from an ejecting midlevel trough will help focus thunderstorm development by 21-00z. Low-midlevel vertical shear will not be particularly strong and flow aloft will be strongly backed, which suggests a fairly quick growth into a line segment. Isolated damaging gusts and large hail will be possible for a few hours late this afternoon/evening. ...WY and vicinity this afternoon... An embedded vorticity maximum over southeast ID will progress eastward over WY this afternoon/evening. There will be sufficient low-midlevel moisture and surface heating for high-based thunderstorm development by early afternoon in advance of the vorticity maximum. Given steep low-level lapse rates and modest enhancement to midlevel flow (near 30 kt), strong outflow winds of 50-60 mph will be possible with this convection through the afternoon. ..Thompson/Weinman.. 08/14/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1126 AM CDT Wed Aug 14 2024 Valid 141630Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS LATE THIS AFTERNOON INTO TONIGHT FOR THE MIDDLE MO VALLEY... ...SUMMARY... Scattered severe thunderstorms capable of all hazards are possible late this afternoon through the evening across portions of the middle Missouri Valley. ...MO Valley area this afternoon through tonight... An MCV over northwest IA will continue eastward today, while clusters of thunderstorms are ongoing this morning from central MO to northern AR within a low-level warm advection regime. Warm advection will slowly weaken through the day, but convective outflow with the central MO storm cluster may result in those storms persisting well into the afternoon while spreading southward. Otherwise, outflow from the morning convection will slowly modify from eastern KS into southeast NE, in advance of a midlevel shortwave trough over the central High Plains, and an associated surface cold front moving southeastward across northwest KS. The cold front and the front/outflow intersection will focus thunderstorm development late this afternoon/evening from central KS to southeast NE/southwest IA, and storms will subsequently spread eastward tonight as one or more storm clusters/MCSs across northern MO/southern IA. Low-level shear/hodograph curvature will be maintained this afternoon within the modifying outflow across the SLGT risk area, where semi-discrete supercells and a couple of tornadoes will be possible. Isolated very large hail (2-2.5 inches in diameter) will also with any persistent supercells, though the severe threat will transition primarily to damaging winds (60-75 mph) by late evening into tonight as storms grow upscale. Farther northwest, a separate clustering of storms is possible in central SD, south of the ongoing convection across southern ND. Surface heating in cloud breaks and weak ascent downstream from an ejecting midlevel trough will help focus thunderstorm development by 21-00z. Low-midlevel vertical shear will not be particularly strong and flow aloft will be strongly backed, which suggests a fairly quick growth into a line segment. Isolated damaging gusts and large hail will be possible for a few hours late this afternoon/evening. ...WY and vicinity this afternoon... An embedded vorticity maximum over southeast ID will progress eastward over WY this afternoon/evening. There will be sufficient low-midlevel moisture and surface heating for high-based thunderstorm development by early afternoon in advance of the vorticity maximum. Given steep low-level lapse rates and modest enhancement to midlevel flow (near 30 kt), strong outflow winds of 50-60 mph will be possible with this convection through the afternoon. ..Thompson/Weinman.. 08/14/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1044 AM CDT Wed Aug 14 2024 Valid 141700Z - 151200Z The previous forecast remains on track based on morning observations and latest guidance. Isolated thunderstorms remain likely after 00 UTC across far northern CA, spreading into central and eastern OR through 12 UTC Thursday. Pockets of wetting rainfall are possible, but PWAT values around 0.75 inches and storm motions between 20-25 knots should support the potential for sporadic dry lightning strikes over a region with dry fuels. Other forecast concerns outlined in the previous discussion below remain valid. ..Moore.. 08/14/2024 .PREV DISCUSSION... /ISSUED 0126 AM CDT Wed Aug 14 2024/ ...Synopsis... A mid-level shortwave trough is forecast to cross the northern California coast Wednesday evening into Thursday morning, bringing with it forcing for ascent supportive of isolated dry thunderstorms. The greatest chances for dry thunderstorms will be across portions of northern California and southern Oregon. ...Dry Thunderstorms... Forecast sounding profiles still suggest the most unstable/buoyant parcels will originate at temperatures near or colder than 0 C, leaving some uncertainty in charge separation/lightning potential across the Northwest. However, forcing from the shortwave trough should be sufficient enough for at least some thunderstorm development overnight Wednesday into Thursday morning over receptive fuels. ...Dry/Windy... The strongest surface winds supportive of Elevated fire-weather conditions across the Western U.S. will be confined to diurnally/terrain-driven corridors that are too localized for highlights at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1044 AM CDT Wed Aug 14 2024 Valid 141700Z - 151200Z The previous forecast remains on track based on morning observations and latest guidance. Isolated thunderstorms remain likely after 00 UTC across far northern CA, spreading into central and eastern OR through 12 UTC Thursday. Pockets of wetting rainfall are possible, but PWAT values around 0.75 inches and storm motions between 20-25 knots should support the potential for sporadic dry lightning strikes over a region with dry fuels. Other forecast concerns outlined in the previous discussion below remain valid. ..Moore.. 08/14/2024 .PREV DISCUSSION... /ISSUED 0126 AM CDT Wed Aug 14 2024/ ...Synopsis... A mid-level shortwave trough is forecast to cross the northern California coast Wednesday evening into Thursday morning, bringing with it forcing for ascent supportive of isolated dry thunderstorms. The greatest chances for dry thunderstorms will be across portions of northern California and southern Oregon. ...Dry Thunderstorms... Forecast sounding profiles still suggest the most unstable/buoyant parcels will originate at temperatures near or colder than 0 C, leaving some uncertainty in charge separation/lightning potential across the Northwest. However, forcing from the shortwave trough should be sufficient enough for at least some thunderstorm development overnight Wednesday into Thursday morning over receptive fuels. ...Dry/Windy... The strongest surface winds supportive of Elevated fire-weather conditions across the Western U.S. will be confined to diurnally/terrain-driven corridors that are too localized for highlights at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1044 AM CDT Wed Aug 14 2024 Valid 141700Z - 151200Z The previous forecast remains on track based on morning observations and latest guidance. Isolated thunderstorms remain likely after 00 UTC across far northern CA, spreading into central and eastern OR through 12 UTC Thursday. Pockets of wetting rainfall are possible, but PWAT values around 0.75 inches and storm motions between 20-25 knots should support the potential for sporadic dry lightning strikes over a region with dry fuels. Other forecast concerns outlined in the previous discussion below remain valid. ..Moore.. 08/14/2024 .PREV DISCUSSION... /ISSUED 0126 AM CDT Wed Aug 14 2024/ ...Synopsis... A mid-level shortwave trough is forecast to cross the northern California coast Wednesday evening into Thursday morning, bringing with it forcing for ascent supportive of isolated dry thunderstorms. The greatest chances for dry thunderstorms will be across portions of northern California and southern Oregon. ...Dry Thunderstorms... Forecast sounding profiles still suggest the most unstable/buoyant parcels will originate at temperatures near or colder than 0 C, leaving some uncertainty in charge separation/lightning potential across the Northwest. However, forcing from the shortwave trough should be sufficient enough for at least some thunderstorm development overnight Wednesday into Thursday morning over receptive fuels. ...Dry/Windy... The strongest surface winds supportive of Elevated fire-weather conditions across the Western U.S. will be confined to diurnally/terrain-driven corridors that are too localized for highlights at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1044 AM CDT Wed Aug 14 2024 Valid 141700Z - 151200Z The previous forecast remains on track based on morning observations and latest guidance. Isolated thunderstorms remain likely after 00 UTC across far northern CA, spreading into central and eastern OR through 12 UTC Thursday. Pockets of wetting rainfall are possible, but PWAT values around 0.75 inches and storm motions between 20-25 knots should support the potential for sporadic dry lightning strikes over a region with dry fuels. Other forecast concerns outlined in the previous discussion below remain valid. ..Moore.. 08/14/2024 .PREV DISCUSSION... /ISSUED 0126 AM CDT Wed Aug 14 2024/ ...Synopsis... A mid-level shortwave trough is forecast to cross the northern California coast Wednesday evening into Thursday morning, bringing with it forcing for ascent supportive of isolated dry thunderstorms. The greatest chances for dry thunderstorms will be across portions of northern California and southern Oregon. ...Dry Thunderstorms... Forecast sounding profiles still suggest the most unstable/buoyant parcels will originate at temperatures near or colder than 0 C, leaving some uncertainty in charge separation/lightning potential across the Northwest. However, forcing from the shortwave trough should be sufficient enough for at least some thunderstorm development overnight Wednesday into Thursday morning over receptive fuels. ...Dry/Windy... The strongest surface winds supportive of Elevated fire-weather conditions across the Western U.S. will be confined to diurnally/terrain-driven corridors that are too localized for highlights at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1044 AM CDT Wed Aug 14 2024 Valid 141700Z - 151200Z The previous forecast remains on track based on morning observations and latest guidance. Isolated thunderstorms remain likely after 00 UTC across far northern CA, spreading into central and eastern OR through 12 UTC Thursday. Pockets of wetting rainfall are possible, but PWAT values around 0.75 inches and storm motions between 20-25 knots should support the potential for sporadic dry lightning strikes over a region with dry fuels. Other forecast concerns outlined in the previous discussion below remain valid. ..Moore.. 08/14/2024 .PREV DISCUSSION... /ISSUED 0126 AM CDT Wed Aug 14 2024/ ...Synopsis... A mid-level shortwave trough is forecast to cross the northern California coast Wednesday evening into Thursday morning, bringing with it forcing for ascent supportive of isolated dry thunderstorms. The greatest chances for dry thunderstorms will be across portions of northern California and southern Oregon. ...Dry Thunderstorms... Forecast sounding profiles still suggest the most unstable/buoyant parcels will originate at temperatures near or colder than 0 C, leaving some uncertainty in charge separation/lightning potential across the Northwest. However, forcing from the shortwave trough should be sufficient enough for at least some thunderstorm development overnight Wednesday into Thursday morning over receptive fuels. ...Dry/Windy... The strongest surface winds supportive of Elevated fire-weather conditions across the Western U.S. will be confined to diurnally/terrain-driven corridors that are too localized for highlights at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1044 AM CDT Wed Aug 14 2024 Valid 141700Z - 151200Z The previous forecast remains on track based on morning observations and latest guidance. Isolated thunderstorms remain likely after 00 UTC across far northern CA, spreading into central and eastern OR through 12 UTC Thursday. Pockets of wetting rainfall are possible, but PWAT values around 0.75 inches and storm motions between 20-25 knots should support the potential for sporadic dry lightning strikes over a region with dry fuels. Other forecast concerns outlined in the previous discussion below remain valid. ..Moore.. 08/14/2024 .PREV DISCUSSION... /ISSUED 0126 AM CDT Wed Aug 14 2024/ ...Synopsis... A mid-level shortwave trough is forecast to cross the northern California coast Wednesday evening into Thursday morning, bringing with it forcing for ascent supportive of isolated dry thunderstorms. The greatest chances for dry thunderstorms will be across portions of northern California and southern Oregon. ...Dry Thunderstorms... Forecast sounding profiles still suggest the most unstable/buoyant parcels will originate at temperatures near or colder than 0 C, leaving some uncertainty in charge separation/lightning potential across the Northwest. However, forcing from the shortwave trough should be sufficient enough for at least some thunderstorm development overnight Wednesday into Thursday morning over receptive fuels. ...Dry/Windy... The strongest surface winds supportive of Elevated fire-weather conditions across the Western U.S. will be confined to diurnally/terrain-driven corridors that are too localized for highlights at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1044 AM CDT Wed Aug 14 2024 Valid 141700Z - 151200Z The previous forecast remains on track based on morning observations and latest guidance. Isolated thunderstorms remain likely after 00 UTC across far northern CA, spreading into central and eastern OR through 12 UTC Thursday. Pockets of wetting rainfall are possible, but PWAT values around 0.75 inches and storm motions between 20-25 knots should support the potential for sporadic dry lightning strikes over a region with dry fuels. Other forecast concerns outlined in the previous discussion below remain valid. ..Moore.. 08/14/2024 .PREV DISCUSSION... /ISSUED 0126 AM CDT Wed Aug 14 2024/ ...Synopsis... A mid-level shortwave trough is forecast to cross the northern California coast Wednesday evening into Thursday morning, bringing with it forcing for ascent supportive of isolated dry thunderstorms. The greatest chances for dry thunderstorms will be across portions of northern California and southern Oregon. ...Dry Thunderstorms... Forecast sounding profiles still suggest the most unstable/buoyant parcels will originate at temperatures near or colder than 0 C, leaving some uncertainty in charge separation/lightning potential across the Northwest. However, forcing from the shortwave trough should be sufficient enough for at least some thunderstorm development overnight Wednesday into Thursday morning over receptive fuels. ...Dry/Windy... The strongest surface winds supportive of Elevated fire-weather conditions across the Western U.S. will be confined to diurnally/terrain-driven corridors that are too localized for highlights at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1044 AM CDT Wed Aug 14 2024 Valid 141700Z - 151200Z The previous forecast remains on track based on morning observations and latest guidance. Isolated thunderstorms remain likely after 00 UTC across far northern CA, spreading into central and eastern OR through 12 UTC Thursday. Pockets of wetting rainfall are possible, but PWAT values around 0.75 inches and storm motions between 20-25 knots should support the potential for sporadic dry lightning strikes over a region with dry fuels. Other forecast concerns outlined in the previous discussion below remain valid. ..Moore.. 08/14/2024 .PREV DISCUSSION... /ISSUED 0126 AM CDT Wed Aug 14 2024/ ...Synopsis... A mid-level shortwave trough is forecast to cross the northern California coast Wednesday evening into Thursday morning, bringing with it forcing for ascent supportive of isolated dry thunderstorms. The greatest chances for dry thunderstorms will be across portions of northern California and southern Oregon. ...Dry Thunderstorms... Forecast sounding profiles still suggest the most unstable/buoyant parcels will originate at temperatures near or colder than 0 C, leaving some uncertainty in charge separation/lightning potential across the Northwest. However, forcing from the shortwave trough should be sufficient enough for at least some thunderstorm development overnight Wednesday into Thursday morning over receptive fuels. ...Dry/Windy... The strongest surface winds supportive of Elevated fire-weather conditions across the Western U.S. will be confined to diurnally/terrain-driven corridors that are too localized for highlights at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

Harrisonburg City Council unanimously adopted a resolution declaring a drought warning for the city on Aug. 13. The return of college students to the community, in combination with already high water demand in recent weeks, may increase water demand beyond the city’s water supply capacity. Harrisonburg’s department of public utilities was considering restricting water use for lawn watering to reduce water use. Harrisonburg Daily News-Record (Va.), Aug 13, 2024

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0729 AM CDT Wed Aug 14 2024 Valid 141300Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR EASTERN NEBRASKA...SOUTHWEST IOWA...NORTHEAST KANSAS...AND NORTHWEST MISSOURI... ...SUMMARY... Scattered severe thunderstorms capable of all hazards are possible late this afternoon through the evening across adjacent portions of the mid and lower Missouri Valley. ...Synopsis... Water-vapor imagery this morning shows a mid- to upper-level shortwave trough over WY/CO moving east-northeast. This upper feature is forecast to rotate through the base of a larger-scale trough and move into the eastern ND/northern MN vicinity by daybreak Thursday. In its wake, an upstream perturbation will move from southeast OR/southern ID into NE by late tonight. Consequently, an upper ridge will shift eastward from the lower-mid MO Valley through the mid MS Valley during the period. At the surface, weak/broad low pressure initially over the High Plains is forecast to gradually consolidate as it shifts eastward across the central Plains, in tandem with the advance of the upper trough. As this occurs, a cool front will shift southeastward across the central Plains through the afternoon and evening. Overnight, further consolidation of the surface low is expected as it moves slowly northeastward into southern Minnesota, while the trailing front sharpens, extending from the low southwestward across Kansas and into New Mexico by the end of the period. ...Mid to lower Missouri Valley... Mid morning radar/IR satellite mosaic shows an MCS over northern MO/IA with a well-developed MCV moving east-northeast over northeast NE. This activity will continue to weaken this morning and become increasingly displaced from KS/NE where a renewed focus for thunderstorm development will occur later today. The remnant outflow boundary will likely persist into the afternoon across the southeastern Nebraska/northwestern Missouri/southwestern Iowa area and modify as heating occurs to the west edge of the MCS cirrus canopy. Rich low-level moisture was sampled this morning on the Topeka, KS 12 UTC raob (16.7 g/kg lowest 100-mb mean mixing ratio). Southerly low-level flow will aid in moistening the airmass as insolation contributes to moderate to strong buoyancy (2000-4000 J/kg MLCAPE) by peak heating. By late afternoon as low pressure and the cold front shifts eastward into this area, the low/front and remnant outflow should all provide low-level foci for storm initiation. With enhanced southerly low-level flow ahead of the advancing mid-level trough beneath moderate (30 to 40 kt) mid-level westerlies, resulting shear suggests that initial storms will likely be supercells capable of producing large hail (1 to 2.5 inches in diameter). Enlarged hodographs along and north of the modified outflow boundary suggest a tornado risk will probably accompany a couple of the more intense supercells, where surface to 0.5 km flow remains relatively backed beneath a belt of 30-40 700-mb flow. Given modest flow above 300 mb, upscale growth into a cluster is forecast to occur relatively quickly during the early evening with a band further consolidating into a eastward-moving line by mid to late evening. Coincident with the transition to upscale growth, the tornado risk will gradually wane and severe gusts capable of wind damage will become the primary concern. This activity will likely persist as a linear MCS but the severe threat should lessen with east extent towards the MS River late. ...Wyoming and vicinity eastward across the northern and central Plains... As the upper trough -- comprised of several vorticity maxima embedded in the broader cyclonic flow field -- shifts across the Rockies toward/into the Plains, daytime heating beneath cooler air at mid levels will support modest destabilization across a broad area. Ascent -- focused near favored higher terrain areas and near various weak surface boundaries -- will contribute to widely scattered thunderstorm development during the afternoon. Moderate mid-level westerlies will contribute to shear sufficient for a few stronger storms -- and attendant risks for hail and locally strong/severe wind gusts into the evening hours. ..Smith.. 08/14/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0729 AM CDT Wed Aug 14 2024 Valid 141300Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR EASTERN NEBRASKA...SOUTHWEST IOWA...NORTHEAST KANSAS...AND NORTHWEST MISSOURI... ...SUMMARY... Scattered severe thunderstorms capable of all hazards are possible late this afternoon through the evening across adjacent portions of the mid and lower Missouri Valley. ...Synopsis... Water-vapor imagery this morning shows a mid- to upper-level shortwave trough over WY/CO moving east-northeast. This upper feature is forecast to rotate through the base of a larger-scale trough and move into the eastern ND/northern MN vicinity by daybreak Thursday. In its wake, an upstream perturbation will move from southeast OR/southern ID into NE by late tonight. Consequently, an upper ridge will shift eastward from the lower-mid MO Valley through the mid MS Valley during the period. At the surface, weak/broad low pressure initially over the High Plains is forecast to gradually consolidate as it shifts eastward across the central Plains, in tandem with the advance of the upper trough. As this occurs, a cool front will shift southeastward across the central Plains through the afternoon and evening. Overnight, further consolidation of the surface low is expected as it moves slowly northeastward into southern Minnesota, while the trailing front sharpens, extending from the low southwestward across Kansas and into New Mexico by the end of the period. ...Mid to lower Missouri Valley... Mid morning radar/IR satellite mosaic shows an MCS over northern MO/IA with a well-developed MCV moving east-northeast over northeast NE. This activity will continue to weaken this morning and become increasingly displaced from KS/NE where a renewed focus for thunderstorm development will occur later today. The remnant outflow boundary will likely persist into the afternoon across the southeastern Nebraska/northwestern Missouri/southwestern Iowa area and modify as heating occurs to the west edge of the MCS cirrus canopy. Rich low-level moisture was sampled this morning on the Topeka, KS 12 UTC raob (16.7 g/kg lowest 100-mb mean mixing ratio). Southerly low-level flow will aid in moistening the airmass as insolation contributes to moderate to strong buoyancy (2000-4000 J/kg MLCAPE) by peak heating. By late afternoon as low pressure and the cold front shifts eastward into this area, the low/front and remnant outflow should all provide low-level foci for storm initiation. With enhanced southerly low-level flow ahead of the advancing mid-level trough beneath moderate (30 to 40 kt) mid-level westerlies, resulting shear suggests that initial storms will likely be supercells capable of producing large hail (1 to 2.5 inches in diameter). Enlarged hodographs along and north of the modified outflow boundary suggest a tornado risk will probably accompany a couple of the more intense supercells, where surface to 0.5 km flow remains relatively backed beneath a belt of 30-40 700-mb flow. Given modest flow above 300 mb, upscale growth into a cluster is forecast to occur relatively quickly during the early evening with a band further consolidating into a eastward-moving line by mid to late evening. Coincident with the transition to upscale growth, the tornado risk will gradually wane and severe gusts capable of wind damage will become the primary concern. This activity will likely persist as a linear MCS but the severe threat should lessen with east extent towards the MS River late. ...Wyoming and vicinity eastward across the northern and central Plains... As the upper trough -- comprised of several vorticity maxima embedded in the broader cyclonic flow field -- shifts across the Rockies toward/into the Plains, daytime heating beneath cooler air at mid levels will support modest destabilization across a broad area. Ascent -- focused near favored higher terrain areas and near various weak surface boundaries -- will contribute to widely scattered thunderstorm development during the afternoon. Moderate mid-level westerlies will contribute to shear sufficient for a few stronger storms -- and attendant risks for hail and locally strong/severe wind gusts into the evening hours. ..Smith.. 08/14/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0729 AM CDT Wed Aug 14 2024 Valid 141300Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR EASTERN NEBRASKA...SOUTHWEST IOWA...NORTHEAST KANSAS...AND NORTHWEST MISSOURI... ...SUMMARY... Scattered severe thunderstorms capable of all hazards are possible late this afternoon through the evening across adjacent portions of the mid and lower Missouri Valley. ...Synopsis... Water-vapor imagery this morning shows a mid- to upper-level shortwave trough over WY/CO moving east-northeast. This upper feature is forecast to rotate through the base of a larger-scale trough and move into the eastern ND/northern MN vicinity by daybreak Thursday. In its wake, an upstream perturbation will move from southeast OR/southern ID into NE by late tonight. Consequently, an upper ridge will shift eastward from the lower-mid MO Valley through the mid MS Valley during the period. At the surface, weak/broad low pressure initially over the High Plains is forecast to gradually consolidate as it shifts eastward across the central Plains, in tandem with the advance of the upper trough. As this occurs, a cool front will shift southeastward across the central Plains through the afternoon and evening. Overnight, further consolidation of the surface low is expected as it moves slowly northeastward into southern Minnesota, while the trailing front sharpens, extending from the low southwestward across Kansas and into New Mexico by the end of the period. ...Mid to lower Missouri Valley... Mid morning radar/IR satellite mosaic shows an MCS over northern MO/IA with a well-developed MCV moving east-northeast over northeast NE. This activity will continue to weaken this morning and become increasingly displaced from KS/NE where a renewed focus for thunderstorm development will occur later today. The remnant outflow boundary will likely persist into the afternoon across the southeastern Nebraska/northwestern Missouri/southwestern Iowa area and modify as heating occurs to the west edge of the MCS cirrus canopy. Rich low-level moisture was sampled this morning on the Topeka, KS 12 UTC raob (16.7 g/kg lowest 100-mb mean mixing ratio). Southerly low-level flow will aid in moistening the airmass as insolation contributes to moderate to strong buoyancy (2000-4000 J/kg MLCAPE) by peak heating. By late afternoon as low pressure and the cold front shifts eastward into this area, the low/front and remnant outflow should all provide low-level foci for storm initiation. With enhanced southerly low-level flow ahead of the advancing mid-level trough beneath moderate (30 to 40 kt) mid-level westerlies, resulting shear suggests that initial storms will likely be supercells capable of producing large hail (1 to 2.5 inches in diameter). Enlarged hodographs along and north of the modified outflow boundary suggest a tornado risk will probably accompany a couple of the more intense supercells, where surface to 0.5 km flow remains relatively backed beneath a belt of 30-40 700-mb flow. Given modest flow above 300 mb, upscale growth into a cluster is forecast to occur relatively quickly during the early evening with a band further consolidating into a eastward-moving line by mid to late evening. Coincident with the transition to upscale growth, the tornado risk will gradually wane and severe gusts capable of wind damage will become the primary concern. This activity will likely persist as a linear MCS but the severe threat should lessen with east extent towards the MS River late. ...Wyoming and vicinity eastward across the northern and central Plains... As the upper trough -- comprised of several vorticity maxima embedded in the broader cyclonic flow field -- shifts across the Rockies toward/into the Plains, daytime heating beneath cooler air at mid levels will support modest destabilization across a broad area. Ascent -- focused near favored higher terrain areas and near various weak surface boundaries -- will contribute to widely scattered thunderstorm development during the afternoon. Moderate mid-level westerlies will contribute to shear sufficient for a few stronger storms -- and attendant risks for hail and locally strong/severe wind gusts into the evening hours. ..Smith.. 08/14/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0729 AM CDT Wed Aug 14 2024 Valid 141300Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR EASTERN NEBRASKA...SOUTHWEST IOWA...NORTHEAST KANSAS...AND NORTHWEST MISSOURI... ...SUMMARY... Scattered severe thunderstorms capable of all hazards are possible late this afternoon through the evening across adjacent portions of the mid and lower Missouri Valley. ...Synopsis... Water-vapor imagery this morning shows a mid- to upper-level shortwave trough over WY/CO moving east-northeast. This upper feature is forecast to rotate through the base of a larger-scale trough and move into the eastern ND/northern MN vicinity by daybreak Thursday. In its wake, an upstream perturbation will move from southeast OR/southern ID into NE by late tonight. Consequently, an upper ridge will shift eastward from the lower-mid MO Valley through the mid MS Valley during the period. At the surface, weak/broad low pressure initially over the High Plains is forecast to gradually consolidate as it shifts eastward across the central Plains, in tandem with the advance of the upper trough. As this occurs, a cool front will shift southeastward across the central Plains through the afternoon and evening. Overnight, further consolidation of the surface low is expected as it moves slowly northeastward into southern Minnesota, while the trailing front sharpens, extending from the low southwestward across Kansas and into New Mexico by the end of the period. ...Mid to lower Missouri Valley... Mid morning radar/IR satellite mosaic shows an MCS over northern MO/IA with a well-developed MCV moving east-northeast over northeast NE. This activity will continue to weaken this morning and become increasingly displaced from KS/NE where a renewed focus for thunderstorm development will occur later today. The remnant outflow boundary will likely persist into the afternoon across the southeastern Nebraska/northwestern Missouri/southwestern Iowa area and modify as heating occurs to the west edge of the MCS cirrus canopy. Rich low-level moisture was sampled this morning on the Topeka, KS 12 UTC raob (16.7 g/kg lowest 100-mb mean mixing ratio). Southerly low-level flow will aid in moistening the airmass as insolation contributes to moderate to strong buoyancy (2000-4000 J/kg MLCAPE) by peak heating. By late afternoon as low pressure and the cold front shifts eastward into this area, the low/front and remnant outflow should all provide low-level foci for storm initiation. With enhanced southerly low-level flow ahead of the advancing mid-level trough beneath moderate (30 to 40 kt) mid-level westerlies, resulting shear suggests that initial storms will likely be supercells capable of producing large hail (1 to 2.5 inches in diameter). Enlarged hodographs along and north of the modified outflow boundary suggest a tornado risk will probably accompany a couple of the more intense supercells, where surface to 0.5 km flow remains relatively backed beneath a belt of 30-40 700-mb flow. Given modest flow above 300 mb, upscale growth into a cluster is forecast to occur relatively quickly during the early evening with a band further consolidating into a eastward-moving line by mid to late evening. Coincident with the transition to upscale growth, the tornado risk will gradually wane and severe gusts capable of wind damage will become the primary concern. This activity will likely persist as a linear MCS but the severe threat should lessen with east extent towards the MS River late. ...Wyoming and vicinity eastward across the northern and central Plains... As the upper trough -- comprised of several vorticity maxima embedded in the broader cyclonic flow field -- shifts across the Rockies toward/into the Plains, daytime heating beneath cooler air at mid levels will support modest destabilization across a broad area. Ascent -- focused near favored higher terrain areas and near various weak surface boundaries -- will contribute to widely scattered thunderstorm development during the afternoon. Moderate mid-level westerlies will contribute to shear sufficient for a few stronger storms -- and attendant risks for hail and locally strong/severe wind gusts into the evening hours. ..Smith.. 08/14/2024 Read more

000
ABPZ20 KNHC 141153
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 AM PDT Wed Aug 14 2024

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

Offshore of Southwestern Mexico:
An area of low pressure could form this weekend well offshore of
southern Mexico. Some slow development is possible by early next
week as the low moves west-northwestward, remaining offshore of
southwestern Mexico.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...30 percent.

Well Southeast of the Hawaiian Islands:
An area of low pressure could form this weekend or early next week
far southeast of the Hawaiian Islands. Some slow development is then
possible as the low moves westward. Information on this system's
development can also be found in the Tropical Weather Outlook for
the Central Pacific basin.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...30 percent.

&&
The Tropical Weather Outlook for the Central Pacific basin can be
found under AWIPS header HFOTWOCP and WMO header ACPN50 PHFO and on
the web at hurricanes.gov

$$
Forecaster Bucci

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0356 AM CDT Wed Aug 14 2024 Valid 171200Z - 221200Z ...DISCUSSION... Medium-range guidance remains in good agreement that upper ridging will remain prominent, and probably further amplify, over much of the Rockies/Plains this weekend into early next week. An upper trough should progress slowly eastward from the Midwest/OH Valley to the eastern states on Day 4/Saturday. While an isolated severe risk may exist across parts of the Mid-Atlantic into the Southeast ahead of a weak front, the overall environment currently appears too marginal given modest deep-layer shear to warrant inclusion of a 15% severe area for Saturday. Otherwise, an upper trough/low should mostly remain off the coast of the Pacific Northwest through at least early next week, before possibly advancing inland towards the end of the forecast period (around Day 8/Wednesday). There is a fair amount of uncertainty regarding potential suppression of the upper ridge early next week. Regardless, the severe threat across the CONUS may tend to remain fairly isolated in this time frame, with the exception of potential MCS development from parts of the Plains into the Midwest/OH Valley in a northwesterly mid-level flow regime. But, predictability remains far too low to include any areas early next week. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0356 AM CDT Wed Aug 14 2024 Valid 171200Z - 221200Z ...DISCUSSION... Medium-range guidance remains in good agreement that upper ridging will remain prominent, and probably further amplify, over much of the Rockies/Plains this weekend into early next week. An upper trough should progress slowly eastward from the Midwest/OH Valley to the eastern states on Day 4/Saturday. While an isolated severe risk may exist across parts of the Mid-Atlantic into the Southeast ahead of a weak front, the overall environment currently appears too marginal given modest deep-layer shear to warrant inclusion of a 15% severe area for Saturday. Otherwise, an upper trough/low should mostly remain off the coast of the Pacific Northwest through at least early next week, before possibly advancing inland towards the end of the forecast period (around Day 8/Wednesday). There is a fair amount of uncertainty regarding potential suppression of the upper ridge early next week. Regardless, the severe threat across the CONUS may tend to remain fairly isolated in this time frame, with the exception of potential MCS development from parts of the Plains into the Midwest/OH Valley in a northwesterly mid-level flow regime. But, predictability remains far too low to include any areas early next week. Read more