Severe Storms

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0741 AM CDT Thu Apr 17 2025 Valid 171300Z - 181200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATE THIS AFTERNOON INTO EARLY TONIGHT FROM EASTERN NEBRASKA INTO WESTERN AND CENTRAL IOWA... ...SUMMARY... Isolated to scattered severe thunderstorms are expected, mainly from late afternoon into early tonight from eastern Nebraska into western and central Iowa. Very large hail to 3 inches in diameter or greater, isolated severe gusts of 60-70 mph, and a couple of tornadoes will all be possible. ...NE/IA/MN/MO through early tonight... Southwest mid-upper flow will persist through the period from the southern High Plains to the central Plains and upper MS Valley, downstream from a large-scale, positive-tilt trough from MB to the Great Basin. A weak surface wave is expected to move along an associated baroclinic from the mid MO Valley to the upper MS Valley, while a lee cyclone develops south-southeastward across the central High Plains. A modifying Gulf air mass (boundary-layer dewpoints in the mid 50s to low 60s) will continue to spread northward in the warm sector from the southern Plains to eastern KS, IA and southern MN, beneath the eastern extent of a relatively warm EML. A cluster of elevated storms, with embedded supercell structures, is ongoing over southwest MO. These storms are expected to weaken this morning as the low-level jet and associated warm advection diminish, coincident with the eastward expansion of the EML. In the interim, isolated large hail (around 1 inch diameter) and strong gusts (50-60 mph) will be possible for a couple of hours this morning across southwest MO. In the wake of the morning convection, surface heating and continued moisture advection will result in steady destabilization from eastern KS to eastern NE/western IA and southern MN. Thunderstorm development is expected near 20z into southern MN where the cap will be a little weaker, and after about 22z in eastern NE (near and just east of the cold front/dryline triple point). The storm environment into southern MN will favor a mix of supercells and storm clusters capable of producing large hail (generally 1-1.75 inch diameter) and isolated strong-severe gusts (50-60 mph). The environment farther south will favor a long-track supercell or two from eastern NE this evening into western/central IA through early tonight, potentially affecting Omaha and Des Moines. Steep midlevel lapse rates, MLCAPE of 2000-2500 J/kg and long hodographs through a deep layer will favor swaths of very large hail (up to 3 inch diameter or greater) and occasional severe gusts of 60-70 mph. There will be a narrow window of opportunity for a couple of tornadoes this evening with sufficient moisture (boundary-layer dewpoints near 60 F) as low-level shear increases. ..Thompson/Grams.. 04/17/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0741 AM CDT Thu Apr 17 2025 Valid 171300Z - 181200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATE THIS AFTERNOON INTO EARLY TONIGHT FROM EASTERN NEBRASKA INTO WESTERN AND CENTRAL IOWA... ...SUMMARY... Isolated to scattered severe thunderstorms are expected, mainly from late afternoon into early tonight from eastern Nebraska into western and central Iowa. Very large hail to 3 inches in diameter or greater, isolated severe gusts of 60-70 mph, and a couple of tornadoes will all be possible. ...NE/IA/MN/MO through early tonight... Southwest mid-upper flow will persist through the period from the southern High Plains to the central Plains and upper MS Valley, downstream from a large-scale, positive-tilt trough from MB to the Great Basin. A weak surface wave is expected to move along an associated baroclinic from the mid MO Valley to the upper MS Valley, while a lee cyclone develops south-southeastward across the central High Plains. A modifying Gulf air mass (boundary-layer dewpoints in the mid 50s to low 60s) will continue to spread northward in the warm sector from the southern Plains to eastern KS, IA and southern MN, beneath the eastern extent of a relatively warm EML. A cluster of elevated storms, with embedded supercell structures, is ongoing over southwest MO. These storms are expected to weaken this morning as the low-level jet and associated warm advection diminish, coincident with the eastward expansion of the EML. In the interim, isolated large hail (around 1 inch diameter) and strong gusts (50-60 mph) will be possible for a couple of hours this morning across southwest MO. In the wake of the morning convection, surface heating and continued moisture advection will result in steady destabilization from eastern KS to eastern NE/western IA and southern MN. Thunderstorm development is expected near 20z into southern MN where the cap will be a little weaker, and after about 22z in eastern NE (near and just east of the cold front/dryline triple point). The storm environment into southern MN will favor a mix of supercells and storm clusters capable of producing large hail (generally 1-1.75 inch diameter) and isolated strong-severe gusts (50-60 mph). The environment farther south will favor a long-track supercell or two from eastern NE this evening into western/central IA through early tonight, potentially affecting Omaha and Des Moines. Steep midlevel lapse rates, MLCAPE of 2000-2500 J/kg and long hodographs through a deep layer will favor swaths of very large hail (up to 3 inch diameter or greater) and occasional severe gusts of 60-70 mph. There will be a narrow window of opportunity for a couple of tornadoes this evening with sufficient moisture (boundary-layer dewpoints near 60 F) as low-level shear increases. ..Thompson/Grams.. 04/17/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0741 AM CDT Thu Apr 17 2025 Valid 171300Z - 181200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATE THIS AFTERNOON INTO EARLY TONIGHT FROM EASTERN NEBRASKA INTO WESTERN AND CENTRAL IOWA... ...SUMMARY... Isolated to scattered severe thunderstorms are expected, mainly from late afternoon into early tonight from eastern Nebraska into western and central Iowa. Very large hail to 3 inches in diameter or greater, isolated severe gusts of 60-70 mph, and a couple of tornadoes will all be possible. ...NE/IA/MN/MO through early tonight... Southwest mid-upper flow will persist through the period from the southern High Plains to the central Plains and upper MS Valley, downstream from a large-scale, positive-tilt trough from MB to the Great Basin. A weak surface wave is expected to move along an associated baroclinic from the mid MO Valley to the upper MS Valley, while a lee cyclone develops south-southeastward across the central High Plains. A modifying Gulf air mass (boundary-layer dewpoints in the mid 50s to low 60s) will continue to spread northward in the warm sector from the southern Plains to eastern KS, IA and southern MN, beneath the eastern extent of a relatively warm EML. A cluster of elevated storms, with embedded supercell structures, is ongoing over southwest MO. These storms are expected to weaken this morning as the low-level jet and associated warm advection diminish, coincident with the eastward expansion of the EML. In the interim, isolated large hail (around 1 inch diameter) and strong gusts (50-60 mph) will be possible for a couple of hours this morning across southwest MO. In the wake of the morning convection, surface heating and continued moisture advection will result in steady destabilization from eastern KS to eastern NE/western IA and southern MN. Thunderstorm development is expected near 20z into southern MN where the cap will be a little weaker, and after about 22z in eastern NE (near and just east of the cold front/dryline triple point). The storm environment into southern MN will favor a mix of supercells and storm clusters capable of producing large hail (generally 1-1.75 inch diameter) and isolated strong-severe gusts (50-60 mph). The environment farther south will favor a long-track supercell or two from eastern NE this evening into western/central IA through early tonight, potentially affecting Omaha and Des Moines. Steep midlevel lapse rates, MLCAPE of 2000-2500 J/kg and long hodographs through a deep layer will favor swaths of very large hail (up to 3 inch diameter or greater) and occasional severe gusts of 60-70 mph. There will be a narrow window of opportunity for a couple of tornadoes this evening with sufficient moisture (boundary-layer dewpoints near 60 F) as low-level shear increases. ..Thompson/Grams.. 04/17/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0741 AM CDT Thu Apr 17 2025 Valid 171300Z - 181200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATE THIS AFTERNOON INTO EARLY TONIGHT FROM EASTERN NEBRASKA INTO WESTERN AND CENTRAL IOWA... ...SUMMARY... Isolated to scattered severe thunderstorms are expected, mainly from late afternoon into early tonight from eastern Nebraska into western and central Iowa. Very large hail to 3 inches in diameter or greater, isolated severe gusts of 60-70 mph, and a couple of tornadoes will all be possible. ...NE/IA/MN/MO through early tonight... Southwest mid-upper flow will persist through the period from the southern High Plains to the central Plains and upper MS Valley, downstream from a large-scale, positive-tilt trough from MB to the Great Basin. A weak surface wave is expected to move along an associated baroclinic from the mid MO Valley to the upper MS Valley, while a lee cyclone develops south-southeastward across the central High Plains. A modifying Gulf air mass (boundary-layer dewpoints in the mid 50s to low 60s) will continue to spread northward in the warm sector from the southern Plains to eastern KS, IA and southern MN, beneath the eastern extent of a relatively warm EML. A cluster of elevated storms, with embedded supercell structures, is ongoing over southwest MO. These storms are expected to weaken this morning as the low-level jet and associated warm advection diminish, coincident with the eastward expansion of the EML. In the interim, isolated large hail (around 1 inch diameter) and strong gusts (50-60 mph) will be possible for a couple of hours this morning across southwest MO. In the wake of the morning convection, surface heating and continued moisture advection will result in steady destabilization from eastern KS to eastern NE/western IA and southern MN. Thunderstorm development is expected near 20z into southern MN where the cap will be a little weaker, and after about 22z in eastern NE (near and just east of the cold front/dryline triple point). The storm environment into southern MN will favor a mix of supercells and storm clusters capable of producing large hail (generally 1-1.75 inch diameter) and isolated strong-severe gusts (50-60 mph). The environment farther south will favor a long-track supercell or two from eastern NE this evening into western/central IA through early tonight, potentially affecting Omaha and Des Moines. Steep midlevel lapse rates, MLCAPE of 2000-2500 J/kg and long hodographs through a deep layer will favor swaths of very large hail (up to 3 inch diameter or greater) and occasional severe gusts of 60-70 mph. There will be a narrow window of opportunity for a couple of tornadoes this evening with sufficient moisture (boundary-layer dewpoints near 60 F) as low-level shear increases. ..Thompson/Grams.. 04/17/2025 Read more

MD 0457 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTHWEST MO
Mesoscale Discussion 0457 NWS Storm Prediction Center Norman OK 0637 AM CDT Thu Apr 17 2025 Areas affected...southwest MO Concerning...Severe potential...Watch unlikely Valid 171137Z - 171300Z Probability of Watch Issuance...5 percent SUMMARY...An isolated severe wind/hail threat may persist for a couple more hours, but should diminish during the mid-morning. DISCUSSION...Early morning convection has largely consolidated into a cluster along the KS/MO border. This activity will probably continue southeastward into southwest MO over the next couple hours. While the leading cell in the cluster has lost its deep core, it may produce a swath of strong gusts. Upstream embedded cell has yielded marginally severe hail and may undergo a similar evolution to the lead cell. This activity will be moving into a progressively drier air mass in MO. In conjunction with diurnal weakening of the low-level jet, this cluster should weaken by late morning. ..Grams/Thompson.. 04/17/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...SGF...EAX... LAT...LON 38439392 38519358 38259276 37929215 37509210 37169227 36929243 36939362 37069420 37739472 38149467 38439392 MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0330 AM CDT Thu Apr 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Sun - ArkLaTex to the Mid-MS Valley... A compact upper shortwave trough is forecast to move from the southern High Plains to the Midwest on Sunday. While some forecast uncertainty continues with regard to exact position of this feature, the overall pattern suggests isolated to scattered severe thunderstorm potential will exist across portions of east TX into the Mid/Lower MS Valley. Strong southwesterly flow aloft will overspread a moist warm sector as a surface low lifts north/northeast from OK into the Lower MO Valley through early evening. A trailing cold front will spread east as this occurs, while a warm front extends eastward from the Mid-MS Valley into the OH Valley. Evolution of prior days convection is resulting in some uncertainty regarding the western/northern extent of severe potential. Nevertheless, a favorable environment supporting at least isolated severe storms should extend from east TX into parts of southern MO/IL ahead of the cold front. ...Days 5-8/Mon-Thu... Forecast ensemble guidance from both the GEFS and EPS suggest low-amplitude west/southwesterly flow will overspread the southern tier of the U.S. next week. Southerly low-level flow on Day 5/Mon across the western Gulf into the southern Plains in the wake of the cold frontal passage on Day 4/Sun will allow for northward transport of modified moisture. This should continue into Day 6/Tue across the Plains. Some localized severe risk could develop across parts of the southern Plains as an upper shortwave trough moves across the north-central U.S. on Day 6/Tue, but poor juxtaposition between higher quality moisture across OK/TX and stronger forcing across the northern Plains/Upper Midwest may limit overall potential. This low-amplitude pattern will continue through Day 8, resulting in low predictability. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0330 AM CDT Thu Apr 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Sun - ArkLaTex to the Mid-MS Valley... A compact upper shortwave trough is forecast to move from the southern High Plains to the Midwest on Sunday. While some forecast uncertainty continues with regard to exact position of this feature, the overall pattern suggests isolated to scattered severe thunderstorm potential will exist across portions of east TX into the Mid/Lower MS Valley. Strong southwesterly flow aloft will overspread a moist warm sector as a surface low lifts north/northeast from OK into the Lower MO Valley through early evening. A trailing cold front will spread east as this occurs, while a warm front extends eastward from the Mid-MS Valley into the OH Valley. Evolution of prior days convection is resulting in some uncertainty regarding the western/northern extent of severe potential. Nevertheless, a favorable environment supporting at least isolated severe storms should extend from east TX into parts of southern MO/IL ahead of the cold front. ...Days 5-8/Mon-Thu... Forecast ensemble guidance from both the GEFS and EPS suggest low-amplitude west/southwesterly flow will overspread the southern tier of the U.S. next week. Southerly low-level flow on Day 5/Mon across the western Gulf into the southern Plains in the wake of the cold frontal passage on Day 4/Sun will allow for northward transport of modified moisture. This should continue into Day 6/Tue across the Plains. Some localized severe risk could develop across parts of the southern Plains as an upper shortwave trough moves across the north-central U.S. on Day 6/Tue, but poor juxtaposition between higher quality moisture across OK/TX and stronger forcing across the northern Plains/Upper Midwest may limit overall potential. This low-amplitude pattern will continue through Day 8, resulting in low predictability. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0330 AM CDT Thu Apr 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Sun - ArkLaTex to the Mid-MS Valley... A compact upper shortwave trough is forecast to move from the southern High Plains to the Midwest on Sunday. While some forecast uncertainty continues with regard to exact position of this feature, the overall pattern suggests isolated to scattered severe thunderstorm potential will exist across portions of east TX into the Mid/Lower MS Valley. Strong southwesterly flow aloft will overspread a moist warm sector as a surface low lifts north/northeast from OK into the Lower MO Valley through early evening. A trailing cold front will spread east as this occurs, while a warm front extends eastward from the Mid-MS Valley into the OH Valley. Evolution of prior days convection is resulting in some uncertainty regarding the western/northern extent of severe potential. Nevertheless, a favorable environment supporting at least isolated severe storms should extend from east TX into parts of southern MO/IL ahead of the cold front. ...Days 5-8/Mon-Thu... Forecast ensemble guidance from both the GEFS and EPS suggest low-amplitude west/southwesterly flow will overspread the southern tier of the U.S. next week. Southerly low-level flow on Day 5/Mon across the western Gulf into the southern Plains in the wake of the cold frontal passage on Day 4/Sun will allow for northward transport of modified moisture. This should continue into Day 6/Tue across the Plains. Some localized severe risk could develop across parts of the southern Plains as an upper shortwave trough moves across the north-central U.S. on Day 6/Tue, but poor juxtaposition between higher quality moisture across OK/TX and stronger forcing across the northern Plains/Upper Midwest may limit overall potential. This low-amplitude pattern will continue through Day 8, resulting in low predictability. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0330 AM CDT Thu Apr 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Sun - ArkLaTex to the Mid-MS Valley... A compact upper shortwave trough is forecast to move from the southern High Plains to the Midwest on Sunday. While some forecast uncertainty continues with regard to exact position of this feature, the overall pattern suggests isolated to scattered severe thunderstorm potential will exist across portions of east TX into the Mid/Lower MS Valley. Strong southwesterly flow aloft will overspread a moist warm sector as a surface low lifts north/northeast from OK into the Lower MO Valley through early evening. A trailing cold front will spread east as this occurs, while a warm front extends eastward from the Mid-MS Valley into the OH Valley. Evolution of prior days convection is resulting in some uncertainty regarding the western/northern extent of severe potential. Nevertheless, a favorable environment supporting at least isolated severe storms should extend from east TX into parts of southern MO/IL ahead of the cold front. ...Days 5-8/Mon-Thu... Forecast ensemble guidance from both the GEFS and EPS suggest low-amplitude west/southwesterly flow will overspread the southern tier of the U.S. next week. Southerly low-level flow on Day 5/Mon across the western Gulf into the southern Plains in the wake of the cold frontal passage on Day 4/Sun will allow for northward transport of modified moisture. This should continue into Day 6/Tue across the Plains. Some localized severe risk could develop across parts of the southern Plains as an upper shortwave trough moves across the north-central U.S. on Day 6/Tue, but poor juxtaposition between higher quality moisture across OK/TX and stronger forcing across the northern Plains/Upper Midwest may limit overall potential. This low-amplitude pattern will continue through Day 8, resulting in low predictability. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0330 AM CDT Thu Apr 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Sun - ArkLaTex to the Mid-MS Valley... A compact upper shortwave trough is forecast to move from the southern High Plains to the Midwest on Sunday. While some forecast uncertainty continues with regard to exact position of this feature, the overall pattern suggests isolated to scattered severe thunderstorm potential will exist across portions of east TX into the Mid/Lower MS Valley. Strong southwesterly flow aloft will overspread a moist warm sector as a surface low lifts north/northeast from OK into the Lower MO Valley through early evening. A trailing cold front will spread east as this occurs, while a warm front extends eastward from the Mid-MS Valley into the OH Valley. Evolution of prior days convection is resulting in some uncertainty regarding the western/northern extent of severe potential. Nevertheless, a favorable environment supporting at least isolated severe storms should extend from east TX into parts of southern MO/IL ahead of the cold front. ...Days 5-8/Mon-Thu... Forecast ensemble guidance from both the GEFS and EPS suggest low-amplitude west/southwesterly flow will overspread the southern tier of the U.S. next week. Southerly low-level flow on Day 5/Mon across the western Gulf into the southern Plains in the wake of the cold frontal passage on Day 4/Sun will allow for northward transport of modified moisture. This should continue into Day 6/Tue across the Plains. Some localized severe risk could develop across parts of the southern Plains as an upper shortwave trough moves across the north-central U.S. on Day 6/Tue, but poor juxtaposition between higher quality moisture across OK/TX and stronger forcing across the northern Plains/Upper Midwest may limit overall potential. This low-amplitude pattern will continue through Day 8, resulting in low predictability. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0330 AM CDT Thu Apr 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Sun - ArkLaTex to the Mid-MS Valley... A compact upper shortwave trough is forecast to move from the southern High Plains to the Midwest on Sunday. While some forecast uncertainty continues with regard to exact position of this feature, the overall pattern suggests isolated to scattered severe thunderstorm potential will exist across portions of east TX into the Mid/Lower MS Valley. Strong southwesterly flow aloft will overspread a moist warm sector as a surface low lifts north/northeast from OK into the Lower MO Valley through early evening. A trailing cold front will spread east as this occurs, while a warm front extends eastward from the Mid-MS Valley into the OH Valley. Evolution of prior days convection is resulting in some uncertainty regarding the western/northern extent of severe potential. Nevertheless, a favorable environment supporting at least isolated severe storms should extend from east TX into parts of southern MO/IL ahead of the cold front. ...Days 5-8/Mon-Thu... Forecast ensemble guidance from both the GEFS and EPS suggest low-amplitude west/southwesterly flow will overspread the southern tier of the U.S. next week. Southerly low-level flow on Day 5/Mon across the western Gulf into the southern Plains in the wake of the cold frontal passage on Day 4/Sun will allow for northward transport of modified moisture. This should continue into Day 6/Tue across the Plains. Some localized severe risk could develop across parts of the southern Plains as an upper shortwave trough moves across the north-central U.S. on Day 6/Tue, but poor juxtaposition between higher quality moisture across OK/TX and stronger forcing across the northern Plains/Upper Midwest may limit overall potential. This low-amplitude pattern will continue through Day 8, resulting in low predictability. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0330 AM CDT Thu Apr 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Sun - ArkLaTex to the Mid-MS Valley... A compact upper shortwave trough is forecast to move from the southern High Plains to the Midwest on Sunday. While some forecast uncertainty continues with regard to exact position of this feature, the overall pattern suggests isolated to scattered severe thunderstorm potential will exist across portions of east TX into the Mid/Lower MS Valley. Strong southwesterly flow aloft will overspread a moist warm sector as a surface low lifts north/northeast from OK into the Lower MO Valley through early evening. A trailing cold front will spread east as this occurs, while a warm front extends eastward from the Mid-MS Valley into the OH Valley. Evolution of prior days convection is resulting in some uncertainty regarding the western/northern extent of severe potential. Nevertheless, a favorable environment supporting at least isolated severe storms should extend from east TX into parts of southern MO/IL ahead of the cold front. ...Days 5-8/Mon-Thu... Forecast ensemble guidance from both the GEFS and EPS suggest low-amplitude west/southwesterly flow will overspread the southern tier of the U.S. next week. Southerly low-level flow on Day 5/Mon across the western Gulf into the southern Plains in the wake of the cold frontal passage on Day 4/Sun will allow for northward transport of modified moisture. This should continue into Day 6/Tue across the Plains. Some localized severe risk could develop across parts of the southern Plains as an upper shortwave trough moves across the north-central U.S. on Day 6/Tue, but poor juxtaposition between higher quality moisture across OK/TX and stronger forcing across the northern Plains/Upper Midwest may limit overall potential. This low-amplitude pattern will continue through Day 8, resulting in low predictability. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0330 AM CDT Thu Apr 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Sun - ArkLaTex to the Mid-MS Valley... A compact upper shortwave trough is forecast to move from the southern High Plains to the Midwest on Sunday. While some forecast uncertainty continues with regard to exact position of this feature, the overall pattern suggests isolated to scattered severe thunderstorm potential will exist across portions of east TX into the Mid/Lower MS Valley. Strong southwesterly flow aloft will overspread a moist warm sector as a surface low lifts north/northeast from OK into the Lower MO Valley through early evening. A trailing cold front will spread east as this occurs, while a warm front extends eastward from the Mid-MS Valley into the OH Valley. Evolution of prior days convection is resulting in some uncertainty regarding the western/northern extent of severe potential. Nevertheless, a favorable environment supporting at least isolated severe storms should extend from east TX into parts of southern MO/IL ahead of the cold front. ...Days 5-8/Mon-Thu... Forecast ensemble guidance from both the GEFS and EPS suggest low-amplitude west/southwesterly flow will overspread the southern tier of the U.S. next week. Southerly low-level flow on Day 5/Mon across the western Gulf into the southern Plains in the wake of the cold frontal passage on Day 4/Sun will allow for northward transport of modified moisture. This should continue into Day 6/Tue across the Plains. Some localized severe risk could develop across parts of the southern Plains as an upper shortwave trough moves across the north-central U.S. on Day 6/Tue, but poor juxtaposition between higher quality moisture across OK/TX and stronger forcing across the northern Plains/Upper Midwest may limit overall potential. This low-amplitude pattern will continue through Day 8, resulting in low predictability. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0330 AM CDT Thu Apr 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Sun - ArkLaTex to the Mid-MS Valley... A compact upper shortwave trough is forecast to move from the southern High Plains to the Midwest on Sunday. While some forecast uncertainty continues with regard to exact position of this feature, the overall pattern suggests isolated to scattered severe thunderstorm potential will exist across portions of east TX into the Mid/Lower MS Valley. Strong southwesterly flow aloft will overspread a moist warm sector as a surface low lifts north/northeast from OK into the Lower MO Valley through early evening. A trailing cold front will spread east as this occurs, while a warm front extends eastward from the Mid-MS Valley into the OH Valley. Evolution of prior days convection is resulting in some uncertainty regarding the western/northern extent of severe potential. Nevertheless, a favorable environment supporting at least isolated severe storms should extend from east TX into parts of southern MO/IL ahead of the cold front. ...Days 5-8/Mon-Thu... Forecast ensemble guidance from both the GEFS and EPS suggest low-amplitude west/southwesterly flow will overspread the southern tier of the U.S. next week. Southerly low-level flow on Day 5/Mon across the western Gulf into the southern Plains in the wake of the cold frontal passage on Day 4/Sun will allow for northward transport of modified moisture. This should continue into Day 6/Tue across the Plains. Some localized severe risk could develop across parts of the southern Plains as an upper shortwave trough moves across the north-central U.S. on Day 6/Tue, but poor juxtaposition between higher quality moisture across OK/TX and stronger forcing across the northern Plains/Upper Midwest may limit overall potential. This low-amplitude pattern will continue through Day 8, resulting in low predictability. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0330 AM CDT Thu Apr 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Sun - ArkLaTex to the Mid-MS Valley... A compact upper shortwave trough is forecast to move from the southern High Plains to the Midwest on Sunday. While some forecast uncertainty continues with regard to exact position of this feature, the overall pattern suggests isolated to scattered severe thunderstorm potential will exist across portions of east TX into the Mid/Lower MS Valley. Strong southwesterly flow aloft will overspread a moist warm sector as a surface low lifts north/northeast from OK into the Lower MO Valley through early evening. A trailing cold front will spread east as this occurs, while a warm front extends eastward from the Mid-MS Valley into the OH Valley. Evolution of prior days convection is resulting in some uncertainty regarding the western/northern extent of severe potential. Nevertheless, a favorable environment supporting at least isolated severe storms should extend from east TX into parts of southern MO/IL ahead of the cold front. ...Days 5-8/Mon-Thu... Forecast ensemble guidance from both the GEFS and EPS suggest low-amplitude west/southwesterly flow will overspread the southern tier of the U.S. next week. Southerly low-level flow on Day 5/Mon across the western Gulf into the southern Plains in the wake of the cold frontal passage on Day 4/Sun will allow for northward transport of modified moisture. This should continue into Day 6/Tue across the Plains. Some localized severe risk could develop across parts of the southern Plains as an upper shortwave trough moves across the north-central U.S. on Day 6/Tue, but poor juxtaposition between higher quality moisture across OK/TX and stronger forcing across the northern Plains/Upper Midwest may limit overall potential. This low-amplitude pattern will continue through Day 8, resulting in low predictability. Read more

MD 0456 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR NORTH-CENTRAL TO EASTERN KS
Mesoscale Discussion 0456 NWS Storm Prediction Center Norman OK 0146 AM CDT Thu Apr 17 2025 Areas affected...north-central to eastern KS Concerning...Severe potential...Watch unlikely Valid 170646Z - 170845Z Probability of Watch Issuance...20 percent SUMMARY...Isolated, marginally severe wind and hail will be possible through dawn as both a cluster of storms in north-central Kansas moves east-southeast and an additional arc of storms develops eastward across eastern Kansas. DISCUSSION...Near-term severe potential is mainly expected across north-central Kansas where a small west/east-oriented cluster recently intensified. With surface temperatures still holding in the upper 60s to lower 70s amid upper 50s surface dew points, the primary threats with this cluster should be strong to localized severe gusts along with marginally severe hail. Even as the associated cold pool might yield a surge to the southeast, the cluster would impinge on warming 700-mb temperatures, which may limit overall intensity. To the southeast of the cluster, along the leading edge of the stout EML, some of these updrafts might deepen as convection spreads east. Small to isolated severe hail should be the primary threat with these semi-discrete cells. ..Grams/Thompson.. 04/17/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...EAX...TOP...ICT...GID... LAT...LON 38569841 38959875 39519880 39739738 39909645 39909580 39829548 39699518 39389492 38809472 38499471 38199498 37859527 37719563 37829653 38409726 38569841 MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 AM CDT Thu Apr 17 2025 Valid 191200Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL TEXAS INTO SOUTHERN MISSOURI... ...SUMMARY... Isolated to scattered severe thunderstorms are possible from central Texas into the Ohio Valley on Saturday. ...Southern Plains to southern MO... An upper shortwave trough over the Southwest will pivot east toward the southern Plains on Saturday/Saturday night. This will maintain strong southwesterly flow aloft from TX into the Midwest. At the surface, a front is expected to be draped from southern IL/MO into northwest TX during the morning, with a dryline extending southward across west-central TX in the vicinity of the Big Bend. Southerly low-level flow will maintain a moist airmass ahead of these surface boundaries, with dewpoints generally in the low/mid 60s F. Some convection could be ongoing during the morning in a warm advection regime prior to the low-level jet weakening modestly during the day. Stronger heating ahead of the surface boundary could allow for weak to moderate destabilization by afternoon, and additional convection is likely along the cold front/dryline as large-scale ascent increases with the approach of the upper shortwave trough. Vertical wind profiles suggest supercell potential, but storm mode may quickly trend toward clusters/linear segments. Some risk for large hail and damaging gusts appears possible with this activity during the late afternoon into the nighttime hours, with initial convection developing over TX/OK and spreading into the Ozarks after 00z. ...Ohio Valley... An upper shortwave trough will migrate east across Ontario/Quebec and the Great Lakes on Saturday. This will bring a belt of strong deep-layer westerly flow across the Ohio Valley/Great Lakes/Northeast vicinity. A cold front and associated baroclinic zone will sag south/southeast across the Ohio Valley vicinity with a narrow corridor of modest boundary layer moisture forecast within this region. Severe potential will largely be modulated by ongoing convection Saturday morning and generally weak instability and lapse rates. Nevertheless, strong flow and sufficient instability may support strong gusts with thunderstorm clusters during the morning and afternoon hours. ..Leitman.. 04/17/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 AM CDT Thu Apr 17 2025 Valid 191200Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL TEXAS INTO SOUTHERN MISSOURI... ...SUMMARY... Isolated to scattered severe thunderstorms are possible from central Texas into the Ohio Valley on Saturday. ...Southern Plains to southern MO... An upper shortwave trough over the Southwest will pivot east toward the southern Plains on Saturday/Saturday night. This will maintain strong southwesterly flow aloft from TX into the Midwest. At the surface, a front is expected to be draped from southern IL/MO into northwest TX during the morning, with a dryline extending southward across west-central TX in the vicinity of the Big Bend. Southerly low-level flow will maintain a moist airmass ahead of these surface boundaries, with dewpoints generally in the low/mid 60s F. Some convection could be ongoing during the morning in a warm advection regime prior to the low-level jet weakening modestly during the day. Stronger heating ahead of the surface boundary could allow for weak to moderate destabilization by afternoon, and additional convection is likely along the cold front/dryline as large-scale ascent increases with the approach of the upper shortwave trough. Vertical wind profiles suggest supercell potential, but storm mode may quickly trend toward clusters/linear segments. Some risk for large hail and damaging gusts appears possible with this activity during the late afternoon into the nighttime hours, with initial convection developing over TX/OK and spreading into the Ozarks after 00z. ...Ohio Valley... An upper shortwave trough will migrate east across Ontario/Quebec and the Great Lakes on Saturday. This will bring a belt of strong deep-layer westerly flow across the Ohio Valley/Great Lakes/Northeast vicinity. A cold front and associated baroclinic zone will sag south/southeast across the Ohio Valley vicinity with a narrow corridor of modest boundary layer moisture forecast within this region. Severe potential will largely be modulated by ongoing convection Saturday morning and generally weak instability and lapse rates. Nevertheless, strong flow and sufficient instability may support strong gusts with thunderstorm clusters during the morning and afternoon hours. ..Leitman.. 04/17/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 AM CDT Thu Apr 17 2025 Valid 191200Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL TEXAS INTO SOUTHERN MISSOURI... ...SUMMARY... Isolated to scattered severe thunderstorms are possible from central Texas into the Ohio Valley on Saturday. ...Southern Plains to southern MO... An upper shortwave trough over the Southwest will pivot east toward the southern Plains on Saturday/Saturday night. This will maintain strong southwesterly flow aloft from TX into the Midwest. At the surface, a front is expected to be draped from southern IL/MO into northwest TX during the morning, with a dryline extending southward across west-central TX in the vicinity of the Big Bend. Southerly low-level flow will maintain a moist airmass ahead of these surface boundaries, with dewpoints generally in the low/mid 60s F. Some convection could be ongoing during the morning in a warm advection regime prior to the low-level jet weakening modestly during the day. Stronger heating ahead of the surface boundary could allow for weak to moderate destabilization by afternoon, and additional convection is likely along the cold front/dryline as large-scale ascent increases with the approach of the upper shortwave trough. Vertical wind profiles suggest supercell potential, but storm mode may quickly trend toward clusters/linear segments. Some risk for large hail and damaging gusts appears possible with this activity during the late afternoon into the nighttime hours, with initial convection developing over TX/OK and spreading into the Ozarks after 00z. ...Ohio Valley... An upper shortwave trough will migrate east across Ontario/Quebec and the Great Lakes on Saturday. This will bring a belt of strong deep-layer westerly flow across the Ohio Valley/Great Lakes/Northeast vicinity. A cold front and associated baroclinic zone will sag south/southeast across the Ohio Valley vicinity with a narrow corridor of modest boundary layer moisture forecast within this region. Severe potential will largely be modulated by ongoing convection Saturday morning and generally weak instability and lapse rates. Nevertheless, strong flow and sufficient instability may support strong gusts with thunderstorm clusters during the morning and afternoon hours. ..Leitman.. 04/17/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 AM CDT Thu Apr 17 2025 Valid 191200Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL TEXAS INTO SOUTHERN MISSOURI... ...SUMMARY... Isolated to scattered severe thunderstorms are possible from central Texas into the Ohio Valley on Saturday. ...Southern Plains to southern MO... An upper shortwave trough over the Southwest will pivot east toward the southern Plains on Saturday/Saturday night. This will maintain strong southwesterly flow aloft from TX into the Midwest. At the surface, a front is expected to be draped from southern IL/MO into northwest TX during the morning, with a dryline extending southward across west-central TX in the vicinity of the Big Bend. Southerly low-level flow will maintain a moist airmass ahead of these surface boundaries, with dewpoints generally in the low/mid 60s F. Some convection could be ongoing during the morning in a warm advection regime prior to the low-level jet weakening modestly during the day. Stronger heating ahead of the surface boundary could allow for weak to moderate destabilization by afternoon, and additional convection is likely along the cold front/dryline as large-scale ascent increases with the approach of the upper shortwave trough. Vertical wind profiles suggest supercell potential, but storm mode may quickly trend toward clusters/linear segments. Some risk for large hail and damaging gusts appears possible with this activity during the late afternoon into the nighttime hours, with initial convection developing over TX/OK and spreading into the Ozarks after 00z. ...Ohio Valley... An upper shortwave trough will migrate east across Ontario/Quebec and the Great Lakes on Saturday. This will bring a belt of strong deep-layer westerly flow across the Ohio Valley/Great Lakes/Northeast vicinity. A cold front and associated baroclinic zone will sag south/southeast across the Ohio Valley vicinity with a narrow corridor of modest boundary layer moisture forecast within this region. Severe potential will largely be modulated by ongoing convection Saturday morning and generally weak instability and lapse rates. Nevertheless, strong flow and sufficient instability may support strong gusts with thunderstorm clusters during the morning and afternoon hours. ..Leitman.. 04/17/2025 Read more