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SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0430 PM CDT Wed Sep 18 2024 Valid 201200Z - 261200Z An active mid-level flow regime is expected across the CONUS over the next seven days. Troughing over the western US will gradually move eastward as an embedded speed max passes over the Southern Rockies/Plains this weekend with gusty winds and dry conditions. By early next week, troughing will move over the central CONUS favoring cooler and wetter conditions. At the same time, ridging should redevelop to the west. Some potential for easterly offshore winds could develop over parts of CA and OR early next week, but significant forecast uncertainty is present in the medium range. This suggests the threat for fire-weather conditions is relatively low. ...Southern Plains... As troughing gradually moves eastward, stronger southwesterly flow aloft will overspread parts of the Southern Rockies/Plains late this week and into the first half of the weekend. A lee low will quickly deepen over eastern CO supporting periods of gusty downlope winds, with gusts of 25-30 mph. However, moisture return ahead of the low will favor higher RH values. Additionally, recent precipitation has likely tempered fuels somewhat, with more precipitation likely in into this weekend. Thus, while some risk for fire-weather conditions may develop over the Plains, confidence is low. ..Lyons.. 09/18/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0430 PM CDT Wed Sep 18 2024 Valid 201200Z - 261200Z An active mid-level flow regime is expected across the CONUS over the next seven days. Troughing over the western US will gradually move eastward as an embedded speed max passes over the Southern Rockies/Plains this weekend with gusty winds and dry conditions. By early next week, troughing will move over the central CONUS favoring cooler and wetter conditions. At the same time, ridging should redevelop to the west. Some potential for easterly offshore winds could develop over parts of CA and OR early next week, but significant forecast uncertainty is present in the medium range. This suggests the threat for fire-weather conditions is relatively low. ...Southern Plains... As troughing gradually moves eastward, stronger southwesterly flow aloft will overspread parts of the Southern Rockies/Plains late this week and into the first half of the weekend. A lee low will quickly deepen over eastern CO supporting periods of gusty downlope winds, with gusts of 25-30 mph. However, moisture return ahead of the low will favor higher RH values. Additionally, recent precipitation has likely tempered fuels somewhat, with more precipitation likely in into this weekend. Thus, while some risk for fire-weather conditions may develop over the Plains, confidence is low. ..Lyons.. 09/18/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0430 PM CDT Wed Sep 18 2024 Valid 201200Z - 261200Z An active mid-level flow regime is expected across the CONUS over the next seven days. Troughing over the western US will gradually move eastward as an embedded speed max passes over the Southern Rockies/Plains this weekend with gusty winds and dry conditions. By early next week, troughing will move over the central CONUS favoring cooler and wetter conditions. At the same time, ridging should redevelop to the west. Some potential for easterly offshore winds could develop over parts of CA and OR early next week, but significant forecast uncertainty is present in the medium range. This suggests the threat for fire-weather conditions is relatively low. ...Southern Plains... As troughing gradually moves eastward, stronger southwesterly flow aloft will overspread parts of the Southern Rockies/Plains late this week and into the first half of the weekend. A lee low will quickly deepen over eastern CO supporting periods of gusty downlope winds, with gusts of 25-30 mph. However, moisture return ahead of the low will favor higher RH values. Additionally, recent precipitation has likely tempered fuels somewhat, with more precipitation likely in into this weekend. Thus, while some risk for fire-weather conditions may develop over the Plains, confidence is low. ..Lyons.. 09/18/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0430 PM CDT Wed Sep 18 2024 Valid 201200Z - 261200Z An active mid-level flow regime is expected across the CONUS over the next seven days. Troughing over the western US will gradually move eastward as an embedded speed max passes over the Southern Rockies/Plains this weekend with gusty winds and dry conditions. By early next week, troughing will move over the central CONUS favoring cooler and wetter conditions. At the same time, ridging should redevelop to the west. Some potential for easterly offshore winds could develop over parts of CA and OR early next week, but significant forecast uncertainty is present in the medium range. This suggests the threat for fire-weather conditions is relatively low. ...Southern Plains... As troughing gradually moves eastward, stronger southwesterly flow aloft will overspread parts of the Southern Rockies/Plains late this week and into the first half of the weekend. A lee low will quickly deepen over eastern CO supporting periods of gusty downlope winds, with gusts of 25-30 mph. However, moisture return ahead of the low will favor higher RH values. Additionally, recent precipitation has likely tempered fuels somewhat, with more precipitation likely in into this weekend. Thus, while some risk for fire-weather conditions may develop over the Plains, confidence is low. ..Lyons.. 09/18/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0430 PM CDT Wed Sep 18 2024 Valid 201200Z - 261200Z An active mid-level flow regime is expected across the CONUS over the next seven days. Troughing over the western US will gradually move eastward as an embedded speed max passes over the Southern Rockies/Plains this weekend with gusty winds and dry conditions. By early next week, troughing will move over the central CONUS favoring cooler and wetter conditions. At the same time, ridging should redevelop to the west. Some potential for easterly offshore winds could develop over parts of CA and OR early next week, but significant forecast uncertainty is present in the medium range. This suggests the threat for fire-weather conditions is relatively low. ...Southern Plains... As troughing gradually moves eastward, stronger southwesterly flow aloft will overspread parts of the Southern Rockies/Plains late this week and into the first half of the weekend. A lee low will quickly deepen over eastern CO supporting periods of gusty downlope winds, with gusts of 25-30 mph. However, moisture return ahead of the low will favor higher RH values. Additionally, recent precipitation has likely tempered fuels somewhat, with more precipitation likely in into this weekend. Thus, while some risk for fire-weather conditions may develop over the Plains, confidence is low. ..Lyons.. 09/18/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0430 PM CDT Wed Sep 18 2024 Valid 201200Z - 261200Z An active mid-level flow regime is expected across the CONUS over the next seven days. Troughing over the western US will gradually move eastward as an embedded speed max passes over the Southern Rockies/Plains this weekend with gusty winds and dry conditions. By early next week, troughing will move over the central CONUS favoring cooler and wetter conditions. At the same time, ridging should redevelop to the west. Some potential for easterly offshore winds could develop over parts of CA and OR early next week, but significant forecast uncertainty is present in the medium range. This suggests the threat for fire-weather conditions is relatively low. ...Southern Plains... As troughing gradually moves eastward, stronger southwesterly flow aloft will overspread parts of the Southern Rockies/Plains late this week and into the first half of the weekend. A lee low will quickly deepen over eastern CO supporting periods of gusty downlope winds, with gusts of 25-30 mph. However, moisture return ahead of the low will favor higher RH values. Additionally, recent precipitation has likely tempered fuels somewhat, with more precipitation likely in into this weekend. Thus, while some risk for fire-weather conditions may develop over the Plains, confidence is low. ..Lyons.. 09/18/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0430 PM CDT Wed Sep 18 2024 Valid 201200Z - 261200Z An active mid-level flow regime is expected across the CONUS over the next seven days. Troughing over the western US will gradually move eastward as an embedded speed max passes over the Southern Rockies/Plains this weekend with gusty winds and dry conditions. By early next week, troughing will move over the central CONUS favoring cooler and wetter conditions. At the same time, ridging should redevelop to the west. Some potential for easterly offshore winds could develop over parts of CA and OR early next week, but significant forecast uncertainty is present in the medium range. This suggests the threat for fire-weather conditions is relatively low. ...Southern Plains... As troughing gradually moves eastward, stronger southwesterly flow aloft will overspread parts of the Southern Rockies/Plains late this week and into the first half of the weekend. A lee low will quickly deepen over eastern CO supporting periods of gusty downlope winds, with gusts of 25-30 mph. However, moisture return ahead of the low will favor higher RH values. Additionally, recent precipitation has likely tempered fuels somewhat, with more precipitation likely in into this weekend. Thus, while some risk for fire-weather conditions may develop over the Plains, confidence is low. ..Lyons.. 09/18/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 2083 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PARTS OF EASTERN SOUTH DAKOTA...ADJACENT NORTHEASTERN NEBRASKA AND SOUTHWESTERN MINNESOTA
Mesoscale Discussion 2083 NWS Storm Prediction Center Norman OK 0253 PM CDT Wed Sep 18 2024 Areas affected...parts of eastern South Dakota...adjacent northeastern Nebraska and southwestern Minnesota Concerning...Severe potential...Watch possible Valid 181953Z - 182230Z Probability of Watch Issuance...40 percent SUMMARY...The initiation of one or two strong storms appears possible late this afternoon. Sustained storm development may include the evolution of supercell structures posing a risk for severe hail, and perhaps some potential for a tornado by early evening. Due to the isolated nature, it is not certain that a severe weather watch is needed, but trends are being monitored. DISCUSSION...Although stronger mid-level height falls appear to be shifting to the north, a destabilizing warm sector boundary layer across the eastern South Dakota vicinity will remain beneath weakly difluent cyclonic mid-level flow into early evening. With mixed-layer CAPE now on the order of 1500 J/kg, beneath 30-50 kt southwesterly mid/upper flow, the environment appears at least conditionally supportive of supercells, and low-level hodographs may enlarge with clockwise curvature as southerly flow around 850 mb is forecast to strengthen some (to around 30+ kt) through 22-00Z. Although low-level forcing for sustained convective development remains unclear, weak warm advection to the east of the dryline may be supporting ongoing attempts at deepening convection east of Huron into the Watertown vicinity. And objective analysis has indicated a persistent localized area of enhanced convergence along a confluence zone near/west of Yankton. Model output, including the convection allowing guidance, suggest that probabilities for thunderstorm development are generally low into early evening. However, the initiation of one or two storms appears possible. If this is sustained, this may include the evolution of supercell structures posing a risk for severe hail, and perhaps some potential for a tornado. ..Kerr/Gleason.. 09/18/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MPX...FSD...OAX...ABR...LBF... LAT...LON 45389647 44609622 42819716 42949859 44379830 45219788 45549726 45389647 Read more

The Delaware County Fair Advisory Board canceled fireworks at the 2024 fair as the state continues to face worsening drought. the unanimous decision to forego the fireworks was made after checking with the state fire marshal. The Columbus Dispatch (Ohio), Sept 18, 2024

The mayor of Greenville urged the public to begin conserving water as the water table was exceptionally low. The wells at Mud Creek were at the low end of the range and were not even in use. Greenville Daily Advocate (Ohio), Sept 18, 2024

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Wed Sep 18 2024 Valid 182000Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTHEAST NEBRASKA INTO FAR NORTHWEST IOWA...EASTERN SOUTH DAKOTA...AND WESTERN MINNESOTA... ...SUMMARY... Thunderstorms capable of producing severe wind gusts and large hail are possible today across parts of the eastern Dakotas and Minnesota into the mid Missouri Valley. A marginal severe threat will also extend southward into parts of the central and southern Plains. ...20Z Update... No changes were made to the ongoing forecast. For mesoscale details concerning eastern South Dakota and vicinity, see MCD 2083. Additional details can be found in the previous discussion below. ..Wendt.. 09/18/2024 .PREV DISCUSSION... /ISSUED 1118 AM CDT Wed Sep 18 2024/ ...Northern Plains/Upper Midwest to the Southern High Plains... A closed upper low centered over eastern MT will continue northeastward during the period, reaching southeast SK by early Thursday morning. Upper-level ridging extending northward from the northwest Gulf Coast into the upper MS Valley will slowly shift eastward to the Upper Great Lakes. A belt of enhanced southwesterly mid-level flow will extend from southern CA through the central High Plains, while also wrapping cyclonically through the eastern Dakotas and into southern Canada. At the surface, a trough/front extends southward from central ND into SD and western NE, before continuing southwestward over the central/southern High Plains. This boundary may serve as a focus for renewed thunderstorm development later today. A band of elevated convection has generally moved northward from northeast ND and northwest MN into southern MB. In the wake of this activity, cloud cover remains prevalent across much of the warm sector across the northern Plains/Upper Midwest. Still, filtered daytime heating of an adequately moist boundary layer should aid in the development of around 1500-2000 J/kg of MLCAPE by late afternoon. Isolated to scattered thunderstorms may form along/east of the surface trough/front within a favorable zone of 30-40 kt of effective bulk shear. But, better large-scale forcing associated with the upper low over the northern High Plains will tend to remain displaced north and west (in southern Canada). Accordingly, 12Z high-resolution guidance continues to vary regarding storm coverage across the Slight Risk (isolated versus scattered) given the weaker forcing aloft. Even with this continued uncertainty, various NAM/RAP forecast soundings still suggest a somewhat conditional risk for organized storms (mix of multicells and supercells). Severe hail/wind may accompany the stronger storms from late afternoon through early evening, before this activity eventually weakens. Further south into the central/southern Plains, low-levels are forecast to be somewhat drier near the surface trough, with surface dewpoints expected to mostly range in the upper 50s to low 60s by late afternoon with pronounced boundary-layer mixing. Warmer mid-level temperatures and limited large-scale ascent across these regions should temper the overall intensity of any updrafts that can form and be sustained, and resultant intensity/coverage of this convection. Still, some guidance shows locally greater thunderstorm coverage and resulting isolated severe wind threat from the eastern TX Panhandle into far northwest OK and southern KS during the late afternoon/early evening, where low-level lapse rates should be maximized with robust daytime heating. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Wed Sep 18 2024 Valid 182000Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTHEAST NEBRASKA INTO FAR NORTHWEST IOWA...EASTERN SOUTH DAKOTA...AND WESTERN MINNESOTA... ...SUMMARY... Thunderstorms capable of producing severe wind gusts and large hail are possible today across parts of the eastern Dakotas and Minnesota into the mid Missouri Valley. A marginal severe threat will also extend southward into parts of the central and southern Plains. ...20Z Update... No changes were made to the ongoing forecast. For mesoscale details concerning eastern South Dakota and vicinity, see MCD 2083. Additional details can be found in the previous discussion below. ..Wendt.. 09/18/2024 .PREV DISCUSSION... /ISSUED 1118 AM CDT Wed Sep 18 2024/ ...Northern Plains/Upper Midwest to the Southern High Plains... A closed upper low centered over eastern MT will continue northeastward during the period, reaching southeast SK by early Thursday morning. Upper-level ridging extending northward from the northwest Gulf Coast into the upper MS Valley will slowly shift eastward to the Upper Great Lakes. A belt of enhanced southwesterly mid-level flow will extend from southern CA through the central High Plains, while also wrapping cyclonically through the eastern Dakotas and into southern Canada. At the surface, a trough/front extends southward from central ND into SD and western NE, before continuing southwestward over the central/southern High Plains. This boundary may serve as a focus for renewed thunderstorm development later today. A band of elevated convection has generally moved northward from northeast ND and northwest MN into southern MB. In the wake of this activity, cloud cover remains prevalent across much of the warm sector across the northern Plains/Upper Midwest. Still, filtered daytime heating of an adequately moist boundary layer should aid in the development of around 1500-2000 J/kg of MLCAPE by late afternoon. Isolated to scattered thunderstorms may form along/east of the surface trough/front within a favorable zone of 30-40 kt of effective bulk shear. But, better large-scale forcing associated with the upper low over the northern High Plains will tend to remain displaced north and west (in southern Canada). Accordingly, 12Z high-resolution guidance continues to vary regarding storm coverage across the Slight Risk (isolated versus scattered) given the weaker forcing aloft. Even with this continued uncertainty, various NAM/RAP forecast soundings still suggest a somewhat conditional risk for organized storms (mix of multicells and supercells). Severe hail/wind may accompany the stronger storms from late afternoon through early evening, before this activity eventually weakens. Further south into the central/southern Plains, low-levels are forecast to be somewhat drier near the surface trough, with surface dewpoints expected to mostly range in the upper 50s to low 60s by late afternoon with pronounced boundary-layer mixing. Warmer mid-level temperatures and limited large-scale ascent across these regions should temper the overall intensity of any updrafts that can form and be sustained, and resultant intensity/coverage of this convection. Still, some guidance shows locally greater thunderstorm coverage and resulting isolated severe wind threat from the eastern TX Panhandle into far northwest OK and southern KS during the late afternoon/early evening, where low-level lapse rates should be maximized with robust daytime heating. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Wed Sep 18 2024 Valid 182000Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTHEAST NEBRASKA INTO FAR NORTHWEST IOWA...EASTERN SOUTH DAKOTA...AND WESTERN MINNESOTA... ...SUMMARY... Thunderstorms capable of producing severe wind gusts and large hail are possible today across parts of the eastern Dakotas and Minnesota into the mid Missouri Valley. A marginal severe threat will also extend southward into parts of the central and southern Plains. ...20Z Update... No changes were made to the ongoing forecast. For mesoscale details concerning eastern South Dakota and vicinity, see MCD 2083. Additional details can be found in the previous discussion below. ..Wendt.. 09/18/2024 .PREV DISCUSSION... /ISSUED 1118 AM CDT Wed Sep 18 2024/ ...Northern Plains/Upper Midwest to the Southern High Plains... A closed upper low centered over eastern MT will continue northeastward during the period, reaching southeast SK by early Thursday morning. Upper-level ridging extending northward from the northwest Gulf Coast into the upper MS Valley will slowly shift eastward to the Upper Great Lakes. A belt of enhanced southwesterly mid-level flow will extend from southern CA through the central High Plains, while also wrapping cyclonically through the eastern Dakotas and into southern Canada. At the surface, a trough/front extends southward from central ND into SD and western NE, before continuing southwestward over the central/southern High Plains. This boundary may serve as a focus for renewed thunderstorm development later today. A band of elevated convection has generally moved northward from northeast ND and northwest MN into southern MB. In the wake of this activity, cloud cover remains prevalent across much of the warm sector across the northern Plains/Upper Midwest. Still, filtered daytime heating of an adequately moist boundary layer should aid in the development of around 1500-2000 J/kg of MLCAPE by late afternoon. Isolated to scattered thunderstorms may form along/east of the surface trough/front within a favorable zone of 30-40 kt of effective bulk shear. But, better large-scale forcing associated with the upper low over the northern High Plains will tend to remain displaced north and west (in southern Canada). Accordingly, 12Z high-resolution guidance continues to vary regarding storm coverage across the Slight Risk (isolated versus scattered) given the weaker forcing aloft. Even with this continued uncertainty, various NAM/RAP forecast soundings still suggest a somewhat conditional risk for organized storms (mix of multicells and supercells). Severe hail/wind may accompany the stronger storms from late afternoon through early evening, before this activity eventually weakens. Further south into the central/southern Plains, low-levels are forecast to be somewhat drier near the surface trough, with surface dewpoints expected to mostly range in the upper 50s to low 60s by late afternoon with pronounced boundary-layer mixing. Warmer mid-level temperatures and limited large-scale ascent across these regions should temper the overall intensity of any updrafts that can form and be sustained, and resultant intensity/coverage of this convection. Still, some guidance shows locally greater thunderstorm coverage and resulting isolated severe wind threat from the eastern TX Panhandle into far northwest OK and southern KS during the late afternoon/early evening, where low-level lapse rates should be maximized with robust daytime heating. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Wed Sep 18 2024 Valid 182000Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTHEAST NEBRASKA INTO FAR NORTHWEST IOWA...EASTERN SOUTH DAKOTA...AND WESTERN MINNESOTA... ...SUMMARY... Thunderstorms capable of producing severe wind gusts and large hail are possible today across parts of the eastern Dakotas and Minnesota into the mid Missouri Valley. A marginal severe threat will also extend southward into parts of the central and southern Plains. ...20Z Update... No changes were made to the ongoing forecast. For mesoscale details concerning eastern South Dakota and vicinity, see MCD 2083. Additional details can be found in the previous discussion below. ..Wendt.. 09/18/2024 .PREV DISCUSSION... /ISSUED 1118 AM CDT Wed Sep 18 2024/ ...Northern Plains/Upper Midwest to the Southern High Plains... A closed upper low centered over eastern MT will continue northeastward during the period, reaching southeast SK by early Thursday morning. Upper-level ridging extending northward from the northwest Gulf Coast into the upper MS Valley will slowly shift eastward to the Upper Great Lakes. A belt of enhanced southwesterly mid-level flow will extend from southern CA through the central High Plains, while also wrapping cyclonically through the eastern Dakotas and into southern Canada. At the surface, a trough/front extends southward from central ND into SD and western NE, before continuing southwestward over the central/southern High Plains. This boundary may serve as a focus for renewed thunderstorm development later today. A band of elevated convection has generally moved northward from northeast ND and northwest MN into southern MB. In the wake of this activity, cloud cover remains prevalent across much of the warm sector across the northern Plains/Upper Midwest. Still, filtered daytime heating of an adequately moist boundary layer should aid in the development of around 1500-2000 J/kg of MLCAPE by late afternoon. Isolated to scattered thunderstorms may form along/east of the surface trough/front within a favorable zone of 30-40 kt of effective bulk shear. But, better large-scale forcing associated with the upper low over the northern High Plains will tend to remain displaced north and west (in southern Canada). Accordingly, 12Z high-resolution guidance continues to vary regarding storm coverage across the Slight Risk (isolated versus scattered) given the weaker forcing aloft. Even with this continued uncertainty, various NAM/RAP forecast soundings still suggest a somewhat conditional risk for organized storms (mix of multicells and supercells). Severe hail/wind may accompany the stronger storms from late afternoon through early evening, before this activity eventually weakens. Further south into the central/southern Plains, low-levels are forecast to be somewhat drier near the surface trough, with surface dewpoints expected to mostly range in the upper 50s to low 60s by late afternoon with pronounced boundary-layer mixing. Warmer mid-level temperatures and limited large-scale ascent across these regions should temper the overall intensity of any updrafts that can form and be sustained, and resultant intensity/coverage of this convection. Still, some guidance shows locally greater thunderstorm coverage and resulting isolated severe wind threat from the eastern TX Panhandle into far northwest OK and southern KS during the late afternoon/early evening, where low-level lapse rates should be maximized with robust daytime heating. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Wed Sep 18 2024 Valid 182000Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTHEAST NEBRASKA INTO FAR NORTHWEST IOWA...EASTERN SOUTH DAKOTA...AND WESTERN MINNESOTA... ...SUMMARY... Thunderstorms capable of producing severe wind gusts and large hail are possible today across parts of the eastern Dakotas and Minnesota into the mid Missouri Valley. A marginal severe threat will also extend southward into parts of the central and southern Plains. ...20Z Update... No changes were made to the ongoing forecast. For mesoscale details concerning eastern South Dakota and vicinity, see MCD 2083. Additional details can be found in the previous discussion below. ..Wendt.. 09/18/2024 .PREV DISCUSSION... /ISSUED 1118 AM CDT Wed Sep 18 2024/ ...Northern Plains/Upper Midwest to the Southern High Plains... A closed upper low centered over eastern MT will continue northeastward during the period, reaching southeast SK by early Thursday morning. Upper-level ridging extending northward from the northwest Gulf Coast into the upper MS Valley will slowly shift eastward to the Upper Great Lakes. A belt of enhanced southwesterly mid-level flow will extend from southern CA through the central High Plains, while also wrapping cyclonically through the eastern Dakotas and into southern Canada. At the surface, a trough/front extends southward from central ND into SD and western NE, before continuing southwestward over the central/southern High Plains. This boundary may serve as a focus for renewed thunderstorm development later today. A band of elevated convection has generally moved northward from northeast ND and northwest MN into southern MB. In the wake of this activity, cloud cover remains prevalent across much of the warm sector across the northern Plains/Upper Midwest. Still, filtered daytime heating of an adequately moist boundary layer should aid in the development of around 1500-2000 J/kg of MLCAPE by late afternoon. Isolated to scattered thunderstorms may form along/east of the surface trough/front within a favorable zone of 30-40 kt of effective bulk shear. But, better large-scale forcing associated with the upper low over the northern High Plains will tend to remain displaced north and west (in southern Canada). Accordingly, 12Z high-resolution guidance continues to vary regarding storm coverage across the Slight Risk (isolated versus scattered) given the weaker forcing aloft. Even with this continued uncertainty, various NAM/RAP forecast soundings still suggest a somewhat conditional risk for organized storms (mix of multicells and supercells). Severe hail/wind may accompany the stronger storms from late afternoon through early evening, before this activity eventually weakens. Further south into the central/southern Plains, low-levels are forecast to be somewhat drier near the surface trough, with surface dewpoints expected to mostly range in the upper 50s to low 60s by late afternoon with pronounced boundary-layer mixing. Warmer mid-level temperatures and limited large-scale ascent across these regions should temper the overall intensity of any updrafts that can form and be sustained, and resultant intensity/coverage of this convection. Still, some guidance shows locally greater thunderstorm coverage and resulting isolated severe wind threat from the eastern TX Panhandle into far northwest OK and southern KS during the late afternoon/early evening, where low-level lapse rates should be maximized with robust daytime heating. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Wed Sep 18 2024 Valid 182000Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTHEAST NEBRASKA INTO FAR NORTHWEST IOWA...EASTERN SOUTH DAKOTA...AND WESTERN MINNESOTA... ...SUMMARY... Thunderstorms capable of producing severe wind gusts and large hail are possible today across parts of the eastern Dakotas and Minnesota into the mid Missouri Valley. A marginal severe threat will also extend southward into parts of the central and southern Plains. ...20Z Update... No changes were made to the ongoing forecast. For mesoscale details concerning eastern South Dakota and vicinity, see MCD 2083. Additional details can be found in the previous discussion below. ..Wendt.. 09/18/2024 .PREV DISCUSSION... /ISSUED 1118 AM CDT Wed Sep 18 2024/ ...Northern Plains/Upper Midwest to the Southern High Plains... A closed upper low centered over eastern MT will continue northeastward during the period, reaching southeast SK by early Thursday morning. Upper-level ridging extending northward from the northwest Gulf Coast into the upper MS Valley will slowly shift eastward to the Upper Great Lakes. A belt of enhanced southwesterly mid-level flow will extend from southern CA through the central High Plains, while also wrapping cyclonically through the eastern Dakotas and into southern Canada. At the surface, a trough/front extends southward from central ND into SD and western NE, before continuing southwestward over the central/southern High Plains. This boundary may serve as a focus for renewed thunderstorm development later today. A band of elevated convection has generally moved northward from northeast ND and northwest MN into southern MB. In the wake of this activity, cloud cover remains prevalent across much of the warm sector across the northern Plains/Upper Midwest. Still, filtered daytime heating of an adequately moist boundary layer should aid in the development of around 1500-2000 J/kg of MLCAPE by late afternoon. Isolated to scattered thunderstorms may form along/east of the surface trough/front within a favorable zone of 30-40 kt of effective bulk shear. But, better large-scale forcing associated with the upper low over the northern High Plains will tend to remain displaced north and west (in southern Canada). Accordingly, 12Z high-resolution guidance continues to vary regarding storm coverage across the Slight Risk (isolated versus scattered) given the weaker forcing aloft. Even with this continued uncertainty, various NAM/RAP forecast soundings still suggest a somewhat conditional risk for organized storms (mix of multicells and supercells). Severe hail/wind may accompany the stronger storms from late afternoon through early evening, before this activity eventually weakens. Further south into the central/southern Plains, low-levels are forecast to be somewhat drier near the surface trough, with surface dewpoints expected to mostly range in the upper 50s to low 60s by late afternoon with pronounced boundary-layer mixing. Warmer mid-level temperatures and limited large-scale ascent across these regions should temper the overall intensity of any updrafts that can form and be sustained, and resultant intensity/coverage of this convection. Still, some guidance shows locally greater thunderstorm coverage and resulting isolated severe wind threat from the eastern TX Panhandle into far northwest OK and southern KS during the late afternoon/early evening, where low-level lapse rates should be maximized with robust daytime heating. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Wed Sep 18 2024 Valid 182000Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTHEAST NEBRASKA INTO FAR NORTHWEST IOWA...EASTERN SOUTH DAKOTA...AND WESTERN MINNESOTA... ...SUMMARY... Thunderstorms capable of producing severe wind gusts and large hail are possible today across parts of the eastern Dakotas and Minnesota into the mid Missouri Valley. A marginal severe threat will also extend southward into parts of the central and southern Plains. ...20Z Update... No changes were made to the ongoing forecast. For mesoscale details concerning eastern South Dakota and vicinity, see MCD 2083. Additional details can be found in the previous discussion below. ..Wendt.. 09/18/2024 .PREV DISCUSSION... /ISSUED 1118 AM CDT Wed Sep 18 2024/ ...Northern Plains/Upper Midwest to the Southern High Plains... A closed upper low centered over eastern MT will continue northeastward during the period, reaching southeast SK by early Thursday morning. Upper-level ridging extending northward from the northwest Gulf Coast into the upper MS Valley will slowly shift eastward to the Upper Great Lakes. A belt of enhanced southwesterly mid-level flow will extend from southern CA through the central High Plains, while also wrapping cyclonically through the eastern Dakotas and into southern Canada. At the surface, a trough/front extends southward from central ND into SD and western NE, before continuing southwestward over the central/southern High Plains. This boundary may serve as a focus for renewed thunderstorm development later today. A band of elevated convection has generally moved northward from northeast ND and northwest MN into southern MB. In the wake of this activity, cloud cover remains prevalent across much of the warm sector across the northern Plains/Upper Midwest. Still, filtered daytime heating of an adequately moist boundary layer should aid in the development of around 1500-2000 J/kg of MLCAPE by late afternoon. Isolated to scattered thunderstorms may form along/east of the surface trough/front within a favorable zone of 30-40 kt of effective bulk shear. But, better large-scale forcing associated with the upper low over the northern High Plains will tend to remain displaced north and west (in southern Canada). Accordingly, 12Z high-resolution guidance continues to vary regarding storm coverage across the Slight Risk (isolated versus scattered) given the weaker forcing aloft. Even with this continued uncertainty, various NAM/RAP forecast soundings still suggest a somewhat conditional risk for organized storms (mix of multicells and supercells). Severe hail/wind may accompany the stronger storms from late afternoon through early evening, before this activity eventually weakens. Further south into the central/southern Plains, low-levels are forecast to be somewhat drier near the surface trough, with surface dewpoints expected to mostly range in the upper 50s to low 60s by late afternoon with pronounced boundary-layer mixing. Warmer mid-level temperatures and limited large-scale ascent across these regions should temper the overall intensity of any updrafts that can form and be sustained, and resultant intensity/coverage of this convection. Still, some guidance shows locally greater thunderstorm coverage and resulting isolated severe wind threat from the eastern TX Panhandle into far northwest OK and southern KS during the late afternoon/early evening, where low-level lapse rates should be maximized with robust daytime heating. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Wed Sep 18 2024 Valid 182000Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTHEAST NEBRASKA INTO FAR NORTHWEST IOWA...EASTERN SOUTH DAKOTA...AND WESTERN MINNESOTA... ...SUMMARY... Thunderstorms capable of producing severe wind gusts and large hail are possible today across parts of the eastern Dakotas and Minnesota into the mid Missouri Valley. A marginal severe threat will also extend southward into parts of the central and southern Plains. ...20Z Update... No changes were made to the ongoing forecast. For mesoscale details concerning eastern South Dakota and vicinity, see MCD 2083. Additional details can be found in the previous discussion below. ..Wendt.. 09/18/2024 .PREV DISCUSSION... /ISSUED 1118 AM CDT Wed Sep 18 2024/ ...Northern Plains/Upper Midwest to the Southern High Plains... A closed upper low centered over eastern MT will continue northeastward during the period, reaching southeast SK by early Thursday morning. Upper-level ridging extending northward from the northwest Gulf Coast into the upper MS Valley will slowly shift eastward to the Upper Great Lakes. A belt of enhanced southwesterly mid-level flow will extend from southern CA through the central High Plains, while also wrapping cyclonically through the eastern Dakotas and into southern Canada. At the surface, a trough/front extends southward from central ND into SD and western NE, before continuing southwestward over the central/southern High Plains. This boundary may serve as a focus for renewed thunderstorm development later today. A band of elevated convection has generally moved northward from northeast ND and northwest MN into southern MB. In the wake of this activity, cloud cover remains prevalent across much of the warm sector across the northern Plains/Upper Midwest. Still, filtered daytime heating of an adequately moist boundary layer should aid in the development of around 1500-2000 J/kg of MLCAPE by late afternoon. Isolated to scattered thunderstorms may form along/east of the surface trough/front within a favorable zone of 30-40 kt of effective bulk shear. But, better large-scale forcing associated with the upper low over the northern High Plains will tend to remain displaced north and west (in southern Canada). Accordingly, 12Z high-resolution guidance continues to vary regarding storm coverage across the Slight Risk (isolated versus scattered) given the weaker forcing aloft. Even with this continued uncertainty, various NAM/RAP forecast soundings still suggest a somewhat conditional risk for organized storms (mix of multicells and supercells). Severe hail/wind may accompany the stronger storms from late afternoon through early evening, before this activity eventually weakens. Further south into the central/southern Plains, low-levels are forecast to be somewhat drier near the surface trough, with surface dewpoints expected to mostly range in the upper 50s to low 60s by late afternoon with pronounced boundary-layer mixing. Warmer mid-level temperatures and limited large-scale ascent across these regions should temper the overall intensity of any updrafts that can form and be sustained, and resultant intensity/coverage of this convection. Still, some guidance shows locally greater thunderstorm coverage and resulting isolated severe wind threat from the eastern TX Panhandle into far northwest OK and southern KS during the late afternoon/early evening, where low-level lapse rates should be maximized with robust daytime heating. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Wed Sep 18 2024 Valid 182000Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF NORTHEAST NEBRASKA INTO FAR NORTHWEST IOWA...EASTERN SOUTH DAKOTA...AND WESTERN MINNESOTA... ...SUMMARY... Thunderstorms capable of producing severe wind gusts and large hail are possible today across parts of the eastern Dakotas and Minnesota into the mid Missouri Valley. A marginal severe threat will also extend southward into parts of the central and southern Plains. ...20Z Update... No changes were made to the ongoing forecast. For mesoscale details concerning eastern South Dakota and vicinity, see MCD 2083. Additional details can be found in the previous discussion below. ..Wendt.. 09/18/2024 .PREV DISCUSSION... /ISSUED 1118 AM CDT Wed Sep 18 2024/ ...Northern Plains/Upper Midwest to the Southern High Plains... A closed upper low centered over eastern MT will continue northeastward during the period, reaching southeast SK by early Thursday morning. Upper-level ridging extending northward from the northwest Gulf Coast into the upper MS Valley will slowly shift eastward to the Upper Great Lakes. A belt of enhanced southwesterly mid-level flow will extend from southern CA through the central High Plains, while also wrapping cyclonically through the eastern Dakotas and into southern Canada. At the surface, a trough/front extends southward from central ND into SD and western NE, before continuing southwestward over the central/southern High Plains. This boundary may serve as a focus for renewed thunderstorm development later today. A band of elevated convection has generally moved northward from northeast ND and northwest MN into southern MB. In the wake of this activity, cloud cover remains prevalent across much of the warm sector across the northern Plains/Upper Midwest. Still, filtered daytime heating of an adequately moist boundary layer should aid in the development of around 1500-2000 J/kg of MLCAPE by late afternoon. Isolated to scattered thunderstorms may form along/east of the surface trough/front within a favorable zone of 30-40 kt of effective bulk shear. But, better large-scale forcing associated with the upper low over the northern High Plains will tend to remain displaced north and west (in southern Canada). Accordingly, 12Z high-resolution guidance continues to vary regarding storm coverage across the Slight Risk (isolated versus scattered) given the weaker forcing aloft. Even with this continued uncertainty, various NAM/RAP forecast soundings still suggest a somewhat conditional risk for organized storms (mix of multicells and supercells). Severe hail/wind may accompany the stronger storms from late afternoon through early evening, before this activity eventually weakens. Further south into the central/southern Plains, low-levels are forecast to be somewhat drier near the surface trough, with surface dewpoints expected to mostly range in the upper 50s to low 60s by late afternoon with pronounced boundary-layer mixing. Warmer mid-level temperatures and limited large-scale ascent across these regions should temper the overall intensity of any updrafts that can form and be sustained, and resultant intensity/coverage of this convection. Still, some guidance shows locally greater thunderstorm coverage and resulting isolated severe wind threat from the eastern TX Panhandle into far northwest OK and southern KS during the late afternoon/early evening, where low-level lapse rates should be maximized with robust daytime heating. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0229 PM CDT Wed Sep 18 2024 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... ...20z Update... No changes were made to the prior outlook. Gusty post-frontal winds are possible across parts of the Dakotas, through the Cascade Gaps and parts of northern CA. However, much of the fuels over these areas should remain poorly receptive to fire spread following recent precipitation. See the prior discussion for more info. ..Lyons.. 09/18/2024 .PREV DISCUSSION... /ISSUED 0154 AM CDT Wed Sep 18 2024/ ...Synopsis... In the wake of a midlevel low moving northeastward from the northern Plains into Canada, an expansive surface high will develop across much of the West. At the same time, a deep midlevel low and strong deep-layer southwesterly flow will overspread southern CA and the Lower CO River Valley. Overall, this pattern will limit the overlap of strong surface winds and warm/dry boundary-layer conditions atop dry fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more