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Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0354 AM CDT Tue Jul 30 2024 Valid 021200Z - 071200Z ...DISCUSSION... On Friday and into the weekend, a mid-level trough will slow and eventually stall across the eastern CONUS. Given remnant moisture, expect widespread thunderstorm activity. However, severe weather should be limited by weak shear in the region. A large-amplitude mid-level ridge which is forecast to build across the western CONUS on Thursday and Friday will start to deamplify over the weekend as a series of mid-level shortwave troughs traverse British Columbia and Alberta. The exact evolution of the pattern over the weekend and beyond remains uncertain. There is consensus for multiple mid-level troughs to move through the northern CONUS with at least some lee troughing across the northern Plains. Some severe weather is possible with any of these passing impulses. However, uncertainty remains too high at this time for severe weather probabilities. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0354 AM CDT Tue Jul 30 2024 Valid 021200Z - 071200Z ...DISCUSSION... On Friday and into the weekend, a mid-level trough will slow and eventually stall across the eastern CONUS. Given remnant moisture, expect widespread thunderstorm activity. However, severe weather should be limited by weak shear in the region. A large-amplitude mid-level ridge which is forecast to build across the western CONUS on Thursday and Friday will start to deamplify over the weekend as a series of mid-level shortwave troughs traverse British Columbia and Alberta. The exact evolution of the pattern over the weekend and beyond remains uncertain. There is consensus for multiple mid-level troughs to move through the northern CONUS with at least some lee troughing across the northern Plains. Some severe weather is possible with any of these passing impulses. However, uncertainty remains too high at this time for severe weather probabilities. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0354 AM CDT Tue Jul 30 2024 Valid 021200Z - 071200Z ...DISCUSSION... On Friday and into the weekend, a mid-level trough will slow and eventually stall across the eastern CONUS. Given remnant moisture, expect widespread thunderstorm activity. However, severe weather should be limited by weak shear in the region. A large-amplitude mid-level ridge which is forecast to build across the western CONUS on Thursday and Friday will start to deamplify over the weekend as a series of mid-level shortwave troughs traverse British Columbia and Alberta. The exact evolution of the pattern over the weekend and beyond remains uncertain. There is consensus for multiple mid-level troughs to move through the northern CONUS with at least some lee troughing across the northern Plains. Some severe weather is possible with any of these passing impulses. However, uncertainty remains too high at this time for severe weather probabilities. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0354 AM CDT Tue Jul 30 2024 Valid 021200Z - 071200Z ...DISCUSSION... On Friday and into the weekend, a mid-level trough will slow and eventually stall across the eastern CONUS. Given remnant moisture, expect widespread thunderstorm activity. However, severe weather should be limited by weak shear in the region. A large-amplitude mid-level ridge which is forecast to build across the western CONUS on Thursday and Friday will start to deamplify over the weekend as a series of mid-level shortwave troughs traverse British Columbia and Alberta. The exact evolution of the pattern over the weekend and beyond remains uncertain. There is consensus for multiple mid-level troughs to move through the northern CONUS with at least some lee troughing across the northern Plains. Some severe weather is possible with any of these passing impulses. However, uncertainty remains too high at this time for severe weather probabilities. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0354 AM CDT Tue Jul 30 2024 Valid 021200Z - 071200Z ...DISCUSSION... On Friday and into the weekend, a mid-level trough will slow and eventually stall across the eastern CONUS. Given remnant moisture, expect widespread thunderstorm activity. However, severe weather should be limited by weak shear in the region. A large-amplitude mid-level ridge which is forecast to build across the western CONUS on Thursday and Friday will start to deamplify over the weekend as a series of mid-level shortwave troughs traverse British Columbia and Alberta. The exact evolution of the pattern over the weekend and beyond remains uncertain. There is consensus for multiple mid-level troughs to move through the northern CONUS with at least some lee troughing across the northern Plains. Some severe weather is possible with any of these passing impulses. However, uncertainty remains too high at this time for severe weather probabilities. Read more

MD 1737 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTHERN OH
Mesoscale Discussion 1737 NWS Storm Prediction Center Norman OK 0123 AM CDT Tue Jul 30 2024 Areas affected...southern OH Concerning...Severe potential...Watch unlikely Valid 300623Z - 300800Z Probability of Watch Issuance...5 percent SUMMARY...A brief tornado and localized damaging wind threat may persist for a another hour or two with a cluster moving east-southeast across a portion of southern Ohio. Overall threat is expected to subside before dawn. DISCUSSION...A cluster intensified last hour over southwest OH with at least one TDS noted just southwest of the ILN radar into Clinton County. A surge in IR cloud top cooling occurred just before this TDS and has since warmed, but transient mesovortices remain possible along the leading edge of the gust front. While there is adequate low-level shear in the ILN VWP data, weaker flow with minimal change in direction has persisted above 1 km AGL, suggesting long-term organizational potential will be limited. Downstream buoyancy is increasingly meager with eastern extent (below 500 J/kg) as this cluster progresses east-southeast at around 35 kts. As such, the brief tornado/localized damaging wind threat will probably diminish after about 08Z. ..Grams/Guyer.. 07/30/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...RLX...ILN... LAT...LON 39588368 39718305 39628232 39168206 38818223 38648254 38728303 38848370 39238385 39588368 Read more

MD 1738 CONCERNING SEVERE THUNDERSTORM WATCH 565... FOR WESTERN TO SOUTH-CENTRAL IA
Mesoscale Discussion 1738 NWS Storm Prediction Center Norman OK 0145 AM CDT Tue Jul 30 2024 Areas affected...Western to south-central IA Concerning...Severe Thunderstorm Watch 565... Valid 300645Z - 300745Z The severe weather threat for Severe Thunderstorm Watch 565 continues. SUMMARY...Strong to localized severe gusts may spread east-southeast of WW 565 with approach of a short-line segment over west-central/southwest Iowa. An extension of the watch in area has been coordinated. DISCUSSION...A short-line segment which produced several measured severe wind gusts of 60-70 mph closer to the MO Valley, has appeared to weaken slightly over the past hour. Still, it has produced a few measured wind gusts of 50-60 mph, and similar intensity may persist east-southeastward as the segment approaches the I-35 corridor in central/south-central IA. Longevity of the strong to severe wind threat is uncertain as the line segment and associated MCV progress towards eastern IA. The presence of the MLCAPE gradient should maintain stronger gust potential in the near-term, but relatively weak low-level flow (with the low-level jet well to the southwest in KS) may yield a gradual diminishing trend towards dawn. ..Grams.. 07/30/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DVN...DMX...OAX... LAT...LON 42469476 42309381 42199347 42029274 41739223 41369225 41209229 40999285 40959398 40979490 41279545 41609531 42219481 42469476 Read more

WW 0564 Status Updates
STATUS REPORT ON WW 564 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 ESE VVV TO 25 NNW AXN TO 30 NNE DTL. WW 564 WILL BE ALLOWED TO EXPIRE AT 300800Z. ..GRAMS..07/30/24 ATTN...WFO...FGF...ABR...MPX... STATUS REPORT FOR WS 564 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MNC005-041-111-121-151-300800- MN . MINNESOTA COUNTIES INCLUDED ARE BECKER DOUGLAS OTTER TAIL POPE SWIFT THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 0564 Status Updates
STATUS REPORT ON WW 564 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 ESE VVV TO 25 NNW AXN TO 30 NNE DTL. WW 564 WILL BE ALLOWED TO EXPIRE AT 300800Z. ..GRAMS..07/30/24 ATTN...WFO...FGF...ABR...MPX... STATUS REPORT FOR WS 564 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MNC005-041-111-121-151-300800- MN . MINNESOTA COUNTIES INCLUDED ARE BECKER DOUGLAS OTTER TAIL POPE SWIFT THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 0564 Status Updates
STATUS REPORT ON WW 564 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 ESE VVV TO 25 NNW AXN TO 30 NNE DTL. WW 564 WILL BE ALLOWED TO EXPIRE AT 300800Z. ..GRAMS..07/30/24 ATTN...WFO...FGF...ABR...MPX... STATUS REPORT FOR WS 564 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MNC005-041-111-121-151-300800- MN . MINNESOTA COUNTIES INCLUDED ARE BECKER DOUGLAS OTTER TAIL POPE SWIFT THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 0564 Status Updates
STATUS REPORT ON WW 564 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 ESE VVV TO 25 NNW AXN TO 30 NNE DTL. WW 564 WILL BE ALLOWED TO EXPIRE AT 300800Z. ..GRAMS..07/30/24 ATTN...WFO...FGF...ABR...MPX... STATUS REPORT FOR WS 564 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MNC005-041-111-121-151-300800- MN . MINNESOTA COUNTIES INCLUDED ARE BECKER DOUGLAS OTTER TAIL POPE SWIFT THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 0564 Status Updates
STATUS REPORT ON WW 564 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 ESE VVV TO 25 NNW AXN TO 30 NNE DTL. WW 564 WILL BE ALLOWED TO EXPIRE AT 300800Z. ..GRAMS..07/30/24 ATTN...WFO...FGF...ABR...MPX... STATUS REPORT FOR WS 564 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MNC005-041-111-121-151-300800- MN . MINNESOTA COUNTIES INCLUDED ARE BECKER DOUGLAS OTTER TAIL POPE SWIFT THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 0564 Status Updates
STATUS REPORT ON WW 564 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 ESE VVV TO 25 NNW AXN TO 30 NNE DTL. WW 564 WILL BE ALLOWED TO EXPIRE AT 300800Z. ..GRAMS..07/30/24 ATTN...WFO...FGF...ABR...MPX... STATUS REPORT FOR WS 564 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MNC005-041-111-121-151-300800- MN . MINNESOTA COUNTIES INCLUDED ARE BECKER DOUGLAS OTTER TAIL POPE SWIFT THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 564 SEVERE TSTM MN ND SD 300320Z - 300800Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 564 NWS Storm Prediction Center Norman OK 1020 PM CDT Mon Jul 29 2024 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of West Central Minnesota Southeast North Dakota Northeast South Dakota * Effective this Monday night and Tuesday morning from 1020 PM until 300 AM CDT. * Primary threats include... Scattered damaging wind gusts to 70 mph likely Scattered large hail events to 1.5 inches in diameter possible SUMMARY...A cluster of intense thunderstorms will persist for a few more hours, tracking eastward into west central Minnesota. Damaging wind gusts are the main concern with these storms. The severe thunderstorm watch area is approximately along and 55 statute miles east and west of a line from 20 miles north northeast of Fargo ND to 20 miles west southwest of Ortonville MN. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU4). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 561...WW 562...WW 563... AVIATION...A few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 27030. ...Hart Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0219 AM CDT Tue Jul 30 2024 Valid 011200Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN ILLINOIS...MUCH OF INDIANA...SOUTHWEST OHIO...AND FAR NORTHERN KENTUCKY... ...SUMMARY... Severe thunderstorms are possible in portions of the Great Lakes/Ohio Valley on Thursday. ...Synopsis... A positively-tilted, mid-level shortwave trough will be located near the Upper Midwest Thursday morning and traverse to the southern Great Lakes by early Friday morning. This trough will sharpen/amplify somewhat as it advances southeast. A weak surface low will likely accompany this trough, but the exact location of this surface feature remains unclear due to subtle differences in the forecast 500mb pattern. ...Midwest into the Ohio Valley... A MCS will likely be ongoing in the Midwest/Upper Midwest vicinity on Thursday morning. The evolution/maintenance of this MCS remains unclear and will depend on the exact location of surface features/moisture and the evolution of the mid-level trough. Nonetheless, confidence is high that a very moist low-level airmass (mid 70s dewpoints) will be present across the Midwest/southern Great Lakes on Thursday. This will result in a reservoir of strong instability. In addition, while the exact evolution of the upper pattern remains unclear, the more broad scenario suggests a somewhat sharp/amplifying mid-level trough approaching this unstable airmass. As this occurs, a substantial overlap in moderate/strong instability, moderate shear, and ample forcing is anticipated from central Illinois to southern Ohio and northern Kentucky. Therefore, while details still remain uncertain, evidence in some severe weather threat during the convective period is high enough to support a Slight Risk. ...Carolinas to the Mid-Atlantic... Scattered thunderstorms are possible within weak lee troughing east of the Appalachians. Mid-level lapse rates will only be around 6 C/km which is the primary limiting factor to a greater severe weather threat. However, the moist airmass will result in moderate instability amid effective shear around 25 to 30 knots. This may be sufficient for scattered strong to occasionally severe thunderstorms from the Carolinas to the Delmarva. ..Bentley.. 07/30/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0219 AM CDT Tue Jul 30 2024 Valid 011200Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN ILLINOIS...MUCH OF INDIANA...SOUTHWEST OHIO...AND FAR NORTHERN KENTUCKY... ...SUMMARY... Severe thunderstorms are possible in portions of the Great Lakes/Ohio Valley on Thursday. ...Synopsis... A positively-tilted, mid-level shortwave trough will be located near the Upper Midwest Thursday morning and traverse to the southern Great Lakes by early Friday morning. This trough will sharpen/amplify somewhat as it advances southeast. A weak surface low will likely accompany this trough, but the exact location of this surface feature remains unclear due to subtle differences in the forecast 500mb pattern. ...Midwest into the Ohio Valley... A MCS will likely be ongoing in the Midwest/Upper Midwest vicinity on Thursday morning. The evolution/maintenance of this MCS remains unclear and will depend on the exact location of surface features/moisture and the evolution of the mid-level trough. Nonetheless, confidence is high that a very moist low-level airmass (mid 70s dewpoints) will be present across the Midwest/southern Great Lakes on Thursday. This will result in a reservoir of strong instability. In addition, while the exact evolution of the upper pattern remains unclear, the more broad scenario suggests a somewhat sharp/amplifying mid-level trough approaching this unstable airmass. As this occurs, a substantial overlap in moderate/strong instability, moderate shear, and ample forcing is anticipated from central Illinois to southern Ohio and northern Kentucky. Therefore, while details still remain uncertain, evidence in some severe weather threat during the convective period is high enough to support a Slight Risk. ...Carolinas to the Mid-Atlantic... Scattered thunderstorms are possible within weak lee troughing east of the Appalachians. Mid-level lapse rates will only be around 6 C/km which is the primary limiting factor to a greater severe weather threat. However, the moist airmass will result in moderate instability amid effective shear around 25 to 30 knots. This may be sufficient for scattered strong to occasionally severe thunderstorms from the Carolinas to the Delmarva. ..Bentley.. 07/30/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0219 AM CDT Tue Jul 30 2024 Valid 011200Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN ILLINOIS...MUCH OF INDIANA...SOUTHWEST OHIO...AND FAR NORTHERN KENTUCKY... ...SUMMARY... Severe thunderstorms are possible in portions of the Great Lakes/Ohio Valley on Thursday. ...Synopsis... A positively-tilted, mid-level shortwave trough will be located near the Upper Midwest Thursday morning and traverse to the southern Great Lakes by early Friday morning. This trough will sharpen/amplify somewhat as it advances southeast. A weak surface low will likely accompany this trough, but the exact location of this surface feature remains unclear due to subtle differences in the forecast 500mb pattern. ...Midwest into the Ohio Valley... A MCS will likely be ongoing in the Midwest/Upper Midwest vicinity on Thursday morning. The evolution/maintenance of this MCS remains unclear and will depend on the exact location of surface features/moisture and the evolution of the mid-level trough. Nonetheless, confidence is high that a very moist low-level airmass (mid 70s dewpoints) will be present across the Midwest/southern Great Lakes on Thursday. This will result in a reservoir of strong instability. In addition, while the exact evolution of the upper pattern remains unclear, the more broad scenario suggests a somewhat sharp/amplifying mid-level trough approaching this unstable airmass. As this occurs, a substantial overlap in moderate/strong instability, moderate shear, and ample forcing is anticipated from central Illinois to southern Ohio and northern Kentucky. Therefore, while details still remain uncertain, evidence in some severe weather threat during the convective period is high enough to support a Slight Risk. ...Carolinas to the Mid-Atlantic... Scattered thunderstorms are possible within weak lee troughing east of the Appalachians. Mid-level lapse rates will only be around 6 C/km which is the primary limiting factor to a greater severe weather threat. However, the moist airmass will result in moderate instability amid effective shear around 25 to 30 knots. This may be sufficient for scattered strong to occasionally severe thunderstorms from the Carolinas to the Delmarva. ..Bentley.. 07/30/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0219 AM CDT Tue Jul 30 2024 Valid 011200Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN ILLINOIS...MUCH OF INDIANA...SOUTHWEST OHIO...AND FAR NORTHERN KENTUCKY... ...SUMMARY... Severe thunderstorms are possible in portions of the Great Lakes/Ohio Valley on Thursday. ...Synopsis... A positively-tilted, mid-level shortwave trough will be located near the Upper Midwest Thursday morning and traverse to the southern Great Lakes by early Friday morning. This trough will sharpen/amplify somewhat as it advances southeast. A weak surface low will likely accompany this trough, but the exact location of this surface feature remains unclear due to subtle differences in the forecast 500mb pattern. ...Midwest into the Ohio Valley... A MCS will likely be ongoing in the Midwest/Upper Midwest vicinity on Thursday morning. The evolution/maintenance of this MCS remains unclear and will depend on the exact location of surface features/moisture and the evolution of the mid-level trough. Nonetheless, confidence is high that a very moist low-level airmass (mid 70s dewpoints) will be present across the Midwest/southern Great Lakes on Thursday. This will result in a reservoir of strong instability. In addition, while the exact evolution of the upper pattern remains unclear, the more broad scenario suggests a somewhat sharp/amplifying mid-level trough approaching this unstable airmass. As this occurs, a substantial overlap in moderate/strong instability, moderate shear, and ample forcing is anticipated from central Illinois to southern Ohio and northern Kentucky. Therefore, while details still remain uncertain, evidence in some severe weather threat during the convective period is high enough to support a Slight Risk. ...Carolinas to the Mid-Atlantic... Scattered thunderstorms are possible within weak lee troughing east of the Appalachians. Mid-level lapse rates will only be around 6 C/km which is the primary limiting factor to a greater severe weather threat. However, the moist airmass will result in moderate instability amid effective shear around 25 to 30 knots. This may be sufficient for scattered strong to occasionally severe thunderstorms from the Carolinas to the Delmarva. ..Bentley.. 07/30/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0219 AM CDT Tue Jul 30 2024 Valid 011200Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN ILLINOIS...MUCH OF INDIANA...SOUTHWEST OHIO...AND FAR NORTHERN KENTUCKY... ...SUMMARY... Severe thunderstorms are possible in portions of the Great Lakes/Ohio Valley on Thursday. ...Synopsis... A positively-tilted, mid-level shortwave trough will be located near the Upper Midwest Thursday morning and traverse to the southern Great Lakes by early Friday morning. This trough will sharpen/amplify somewhat as it advances southeast. A weak surface low will likely accompany this trough, but the exact location of this surface feature remains unclear due to subtle differences in the forecast 500mb pattern. ...Midwest into the Ohio Valley... A MCS will likely be ongoing in the Midwest/Upper Midwest vicinity on Thursday morning. The evolution/maintenance of this MCS remains unclear and will depend on the exact location of surface features/moisture and the evolution of the mid-level trough. Nonetheless, confidence is high that a very moist low-level airmass (mid 70s dewpoints) will be present across the Midwest/southern Great Lakes on Thursday. This will result in a reservoir of strong instability. In addition, while the exact evolution of the upper pattern remains unclear, the more broad scenario suggests a somewhat sharp/amplifying mid-level trough approaching this unstable airmass. As this occurs, a substantial overlap in moderate/strong instability, moderate shear, and ample forcing is anticipated from central Illinois to southern Ohio and northern Kentucky. Therefore, while details still remain uncertain, evidence in some severe weather threat during the convective period is high enough to support a Slight Risk. ...Carolinas to the Mid-Atlantic... Scattered thunderstorms are possible within weak lee troughing east of the Appalachians. Mid-level lapse rates will only be around 6 C/km which is the primary limiting factor to a greater severe weather threat. However, the moist airmass will result in moderate instability amid effective shear around 25 to 30 knots. This may be sufficient for scattered strong to occasionally severe thunderstorms from the Carolinas to the Delmarva. ..Bentley.. 07/30/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0219 AM CDT Tue Jul 30 2024 Valid 011200Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN ILLINOIS...MUCH OF INDIANA...SOUTHWEST OHIO...AND FAR NORTHERN KENTUCKY... ...SUMMARY... Severe thunderstorms are possible in portions of the Great Lakes/Ohio Valley on Thursday. ...Synopsis... A positively-tilted, mid-level shortwave trough will be located near the Upper Midwest Thursday morning and traverse to the southern Great Lakes by early Friday morning. This trough will sharpen/amplify somewhat as it advances southeast. A weak surface low will likely accompany this trough, but the exact location of this surface feature remains unclear due to subtle differences in the forecast 500mb pattern. ...Midwest into the Ohio Valley... A MCS will likely be ongoing in the Midwest/Upper Midwest vicinity on Thursday morning. The evolution/maintenance of this MCS remains unclear and will depend on the exact location of surface features/moisture and the evolution of the mid-level trough. Nonetheless, confidence is high that a very moist low-level airmass (mid 70s dewpoints) will be present across the Midwest/southern Great Lakes on Thursday. This will result in a reservoir of strong instability. In addition, while the exact evolution of the upper pattern remains unclear, the more broad scenario suggests a somewhat sharp/amplifying mid-level trough approaching this unstable airmass. As this occurs, a substantial overlap in moderate/strong instability, moderate shear, and ample forcing is anticipated from central Illinois to southern Ohio and northern Kentucky. Therefore, while details still remain uncertain, evidence in some severe weather threat during the convective period is high enough to support a Slight Risk. ...Carolinas to the Mid-Atlantic... Scattered thunderstorms are possible within weak lee troughing east of the Appalachians. Mid-level lapse rates will only be around 6 C/km which is the primary limiting factor to a greater severe weather threat. However, the moist airmass will result in moderate instability amid effective shear around 25 to 30 knots. This may be sufficient for scattered strong to occasionally severe thunderstorms from the Carolinas to the Delmarva. ..Bentley.. 07/30/2024 Read more