Severe Storms

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0452 PM CDT Tue Jul 02 2024 Valid 041200Z - 101200Z An unusually strong ridge of high pressure will dominate the West Coast synoptic pattern through the extended forecast period. 600 DAM 500 mb heights will allow for extreme heat and very dry surface conditions to develop over much of the Southwest and Great Basin. Several weak upper troughs will move along the eastern edge of the ridge supporting occasional stronger surface winds and some fire danger. Otherwise, modest synoptic winds will occur under the ridge over much of the West, with near record temperatures and rapid drying of fuels likely. ...Northwest and Great Basin... As the strong ridge of high pressure intensifies this week, several modest perturbations will move around the top and eastern periphery of the ridge over the Northwest and northern Great Basin late in the week and into the weekend. With several days of hot and very dry conditions expected prior, gusty downslope winds of 15-25 mph could support localized fire-weather concerns across the lee of the Cascades and western Columbia Basin D3/Thursday and D4/Friday. Confidence in the coverage of stronger winds and uncertainties in fuel availability will preclude probabilities for now. More significant fire-weather concerns appear likely this weekend as the upper trough and associated jet streak move south into the Great Basin. A wind shift at the surface will accompany the upper trough as breezy northwest surface winds to 20-25 mph develop behind it across parts of southern ID, northern NV and western UT D5/Saturday. Very warm temperatures and low RH of 10-15% will precede the increase in winds, supporting an increased risk for critical fire-weather conditions. D6/Sunday and beyond, confidence in the evolution of the upper ridge and the associated synoptic pattern decreases substantially. Some risk for dry and breezy conditions may continue with northwesterly flow aloft across parts of the Southwest and Great Basin. However, the spatial coverage and uncertainties in fuels lend low confidence in the potential for critical fire-weather conditions at this time. ...Southern CA... Periodic offshore and terrain-enhanced flow is expected over parts of southern CA late this week. South of the ridge of high pressure, light easterly mid-level winds are expected to overspread the Desert Southwest and southern CA. While weak, somewhat enhanced low-level pressure gradients may support a few hours of breezy downslope winds near 20-25 mph overnight D3/Thursday through D5/Friday. With very hot and dry conditions likely beneath the ridge, localized near-critical fire-weather conditions may occur with these weak Sundowner winds and across parts of the southern CA Valleys. Winds should dissipate this weekend as the upper ridge shifts eastward and the weak upper-level support lessens. ..Lyons/Halbert.. 07/02/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

WW 0498 Status Updates
STATUS FOR WATCH 0498 HAS NOT BEEN ISSUED YET Read more

WW 0498 Status Updates
STATUS FOR WATCH 0498 HAS NOT BEEN ISSUED YET Read more

WW 0497 Status Updates
STATUS REPORT ON WW 497 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 45 NW LWD TO 30 NNE OXV TO 25 SW ALO. ..SQUITIERI..07/02/24 ATTN...WFO...DMX...DVN...EAX... STATUS REPORT FOR WT 497 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC015-071-073-085-131-161-187-195-022240- IL . ILLINOIS COUNTIES INCLUDED ARE CARROLL HENDERSON HENRY JO DAVIESS MERCER ROCK ISLAND WARREN WHITESIDE IAC007-011-031-039-045-051-053-057-087-095-097-099-101-103-105- 107-111-113-115-117-121-123-125-135-139-157-159-163-171-175-177- 179-181-183-185-022240- IA . IOWA COUNTIES INCLUDED ARE APPANOOSE BENTON CEDAR CLARKE CLINTON DAVIS DECATUR DES MOINES HENRY IOWA JACKSON JASPER JEFFERSON JOHNSON JONES KEOKUK LEE LINN LOUISA LUCAS MADISON MAHASKA MARION MONROE Read more

MD 1511 CONCERNING SEVERE POTENTIAL...WATCH LIKELY FOR FAR NORTHEAST KS...SOUTHERN IA...NORTHERN MO
Mesoscale Discussion 1511 NWS Storm Prediction Center Norman OK 0224 PM CDT Tue Jul 02 2024 Areas affected...Far Northeast KS...Southern IA...Northern MO Concerning...Severe potential...Watch likely Valid 021924Z - 022130Z Probability of Watch Issuance...80 percent SUMMARY...Thunderstorms are expected to develop across northern Missouri and southern Iowa this afternoon. Environmental conditions support severe thunderstorms capable of large hail from 1 to 1.75" and gusts to 70 mph. A few tornadoes are possible as well. DISCUSSION...Visible satellite imagery has shown an increasingly agitated cumulus field over far northwest MO and adjacent south-central IA. This cumulus is building within an area of moderate low-level convergence just to the south of a warm front extending eastward from the far southern IA/NE border across southern IA and then southeastward to the IA/MO/IL border intersection vicinity. Temperatures immediately south of this front are in the mid to upper 80s with dewpoints in the low 70s. These warm and moist low-level conditions are supporting strong buoyancy, with recent mesoanalysis estimating MLCAPE from 2000 to 2500 J/kg. Continued heating and low-level moisture advection could help push MLCAPE over 3000 J/kg over the next hour or two. Flat character to much of the cumulus suggest some convective inhibition likely remains across a majority of the region. However, recent mesoanalysis and modified forecast soundings suggest that only minimal convective inhibition remains and some of the more recent cumulus development appears to have a sharper character. All of these factors indicate that convective initiation will likely occur soon. Moderate deep-layer vertical shear is already place, evidenced by the 18Z TOP sounding sampling 40 kt of 0-6 km bulk shear. This matches the recent mesoanalysis, which is estimating 40 to 50 kt. This is sufficient for organized convection, including a few supercells if a discrete mode can be maintained. Low-level flow will likely be veered, but some strengthening in the 850 to 700 mb layer could still help elongate hodographs, supporting some tornado potential. This potential will be augmented by increased vorticity near the warm front. Some large hail from 1 to 1.75" is possible and water-loaded downbursts are possible as well. After an initially cellular mode, upscale growth into an organized convective line appears likely, with damaging gusts as the primary severe risk. Given this severe potential, a watch will likely be needed across portions of the area. ..Mosier/Gleason.. 07/02/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LSX...DVN...DMX...EAX...OAX... LAT...LON 39959207 39589461 40409549 41169494 41849344 42259127 40739119 39959207 Read more

WW 0497 Status Updates
STATUS FOR WATCH 0497 HAS NOT BEEN ISSUED YET Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue Jul 02 2024 Valid 022000Z - 031200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN IOWA...NORTHERN MISSOURI...NORTHEAST KANSAS...AND FAR SOUTHEAST NEBRASKA... ...SUMMARY... Scattered to numerous damaging thunderstorm winds, a few tornadoes, and occasional large hail appear most likely this afternoon and early evening over parts of southern/central Iowa, northern Missouri, and northeastern Kansas. ...20z Update... The Marginal (level 1 of 5) risk has been removed from much of NE/SD/WY in the post-frontal airmass. This area is well behind a moist axis oriented across central KS into IA, and dewpoints have generally fallen into the 40s and 50s F with only weak instability noted. Ongoing convection across western NE earlier produced gusts to around 35 kt. While some gusty wind potential will be possible with any storms across the area, overall cover and severe potential appears low. Some modest trimming of the Marginal (level 1 of 5) risk has also been done from eastern NE into northern IA and southeast MN where ongoing clouds and precipitation has largely modified the airmass such that instability is low and severe potential should remain south of this area. Otherwise, refer to the previous outlook below for more forecast details, and MCD 1511 for short term severe information across IA/MO. ..Leitman.. 07/02/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Tue Jul 02 2024/ ...Iowa/Missouri into Northeast Kansas and Vicinity... Elevated thunderstorms with a marginal/isolated hail threat are ongoing late this morning across eastern NE and southern IA in a low-level warm advection regime. This activity is also being aided by modest large-scale ascent associated with a subtle mid-level vorticity maximum moving eastward over the central Plains. The primary upper cyclone and related surface low will remain over central Canada today, with a cold front extending southward over the northern Plains/Upper Midwest and continuing southwestward into the central Plains. An effective warm front extends northeastward from a secondary surface low in north-central KS across northern MO into southern IA. This boundary will likely serve as a focus for severe thunderstorms this afternoon and evening as it attempts to lift further northward into IA. The 12Z sounding from TOP showed a very moist boundary layer, with precipitable water values through the column greater than 2 inches and somewhat steepened mid-level lapse rates. Robust daytime heating of this airmass along/south of the front will likely aid the development of moderate to strong instability by mid afternoon, even though mid-level temperature remain somewhat warm. A belt of stronger (40-55 kt) southwesterly mid-level flow associated with the subtle central Plains shortwave trough will likely overspread the frontal zone across IA and northern MO in the same time frame. With sufficient veering/strengthening of the wind field with height through mid-levels, around 35-50 kt of deep-layer shear is expected to promote organized convection, including the potential for both supercells and a bowing cluster. Thunderstorms should intensify by early to mid afternoon near the front across southeast NE/northeast KS into southern/central IA and perhaps northern MO. If this initial development can remain at least semi-discrete for a few hours, then sufficient low-level shear near the warm front would support a threat for a few tornadoes. Isolated severe hail may also occur with any sustained supercell. Otherwise, upscale growth into an MCS by mid to late afternoon appears likely given the mainly linear/frontal forcing and mid-level flow aligned mostly parallel to the surface front. Scattered to numerous damaging winds generally ranging 60-70 mph should become the primary severe hazard by late afternoon and early evening across IA and northern MO, but embedded QLCS circulations will also be possible. Convection should tend to weaken later this evening as it approaches the MS River and encounters a less unstable airmass. ...Southern/Central Plains... Additional convection should develop along the front with southwestward extent into KS and the southern/central High Plains. Given a well-mixed boundary layer and steepened low-level lapse rates with daytime heating, isolated to scattered severe/damaging winds should be the main threat with this activity. Modest low-level upslope flow in the post-frontal regime may encourage the development of isolated supercells across parts of southeast CO and vicinity. Occasional large hail and severe wind gusts may occur with any intense convection that can persist, but confidence in a small bowing cluster developing from this activity this evening remains low. Other occasionally strong to severe convection may develop southeastward from eastern WY into western NE this afternoon and evening. Weaker instability across this region should keep the overall severe threat rather isolated. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue Jul 02 2024 Valid 022000Z - 031200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN IOWA...NORTHERN MISSOURI...NORTHEAST KANSAS...AND FAR SOUTHEAST NEBRASKA... ...SUMMARY... Scattered to numerous damaging thunderstorm winds, a few tornadoes, and occasional large hail appear most likely this afternoon and early evening over parts of southern/central Iowa, northern Missouri, and northeastern Kansas. ...20z Update... The Marginal (level 1 of 5) risk has been removed from much of NE/SD/WY in the post-frontal airmass. This area is well behind a moist axis oriented across central KS into IA, and dewpoints have generally fallen into the 40s and 50s F with only weak instability noted. Ongoing convection across western NE earlier produced gusts to around 35 kt. While some gusty wind potential will be possible with any storms across the area, overall cover and severe potential appears low. Some modest trimming of the Marginal (level 1 of 5) risk has also been done from eastern NE into northern IA and southeast MN where ongoing clouds and precipitation has largely modified the airmass such that instability is low and severe potential should remain south of this area. Otherwise, refer to the previous outlook below for more forecast details, and MCD 1511 for short term severe information across IA/MO. ..Leitman.. 07/02/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Tue Jul 02 2024/ ...Iowa/Missouri into Northeast Kansas and Vicinity... Elevated thunderstorms with a marginal/isolated hail threat are ongoing late this morning across eastern NE and southern IA in a low-level warm advection regime. This activity is also being aided by modest large-scale ascent associated with a subtle mid-level vorticity maximum moving eastward over the central Plains. The primary upper cyclone and related surface low will remain over central Canada today, with a cold front extending southward over the northern Plains/Upper Midwest and continuing southwestward into the central Plains. An effective warm front extends northeastward from a secondary surface low in north-central KS across northern MO into southern IA. This boundary will likely serve as a focus for severe thunderstorms this afternoon and evening as it attempts to lift further northward into IA. The 12Z sounding from TOP showed a very moist boundary layer, with precipitable water values through the column greater than 2 inches and somewhat steepened mid-level lapse rates. Robust daytime heating of this airmass along/south of the front will likely aid the development of moderate to strong instability by mid afternoon, even though mid-level temperature remain somewhat warm. A belt of stronger (40-55 kt) southwesterly mid-level flow associated with the subtle central Plains shortwave trough will likely overspread the frontal zone across IA and northern MO in the same time frame. With sufficient veering/strengthening of the wind field with height through mid-levels, around 35-50 kt of deep-layer shear is expected to promote organized convection, including the potential for both supercells and a bowing cluster. Thunderstorms should intensify by early to mid afternoon near the front across southeast NE/northeast KS into southern/central IA and perhaps northern MO. If this initial development can remain at least semi-discrete for a few hours, then sufficient low-level shear near the warm front would support a threat for a few tornadoes. Isolated severe hail may also occur with any sustained supercell. Otherwise, upscale growth into an MCS by mid to late afternoon appears likely given the mainly linear/frontal forcing and mid-level flow aligned mostly parallel to the surface front. Scattered to numerous damaging winds generally ranging 60-70 mph should become the primary severe hazard by late afternoon and early evening across IA and northern MO, but embedded QLCS circulations will also be possible. Convection should tend to weaken later this evening as it approaches the MS River and encounters a less unstable airmass. ...Southern/Central Plains... Additional convection should develop along the front with southwestward extent into KS and the southern/central High Plains. Given a well-mixed boundary layer and steepened low-level lapse rates with daytime heating, isolated to scattered severe/damaging winds should be the main threat with this activity. Modest low-level upslope flow in the post-frontal regime may encourage the development of isolated supercells across parts of southeast CO and vicinity. Occasional large hail and severe wind gusts may occur with any intense convection that can persist, but confidence in a small bowing cluster developing from this activity this evening remains low. Other occasionally strong to severe convection may develop southeastward from eastern WY into western NE this afternoon and evening. Weaker instability across this region should keep the overall severe threat rather isolated. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue Jul 02 2024 Valid 022000Z - 031200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN IOWA...NORTHERN MISSOURI...NORTHEAST KANSAS...AND FAR SOUTHEAST NEBRASKA... ...SUMMARY... Scattered to numerous damaging thunderstorm winds, a few tornadoes, and occasional large hail appear most likely this afternoon and early evening over parts of southern/central Iowa, northern Missouri, and northeastern Kansas. ...20z Update... The Marginal (level 1 of 5) risk has been removed from much of NE/SD/WY in the post-frontal airmass. This area is well behind a moist axis oriented across central KS into IA, and dewpoints have generally fallen into the 40s and 50s F with only weak instability noted. Ongoing convection across western NE earlier produced gusts to around 35 kt. While some gusty wind potential will be possible with any storms across the area, overall cover and severe potential appears low. Some modest trimming of the Marginal (level 1 of 5) risk has also been done from eastern NE into northern IA and southeast MN where ongoing clouds and precipitation has largely modified the airmass such that instability is low and severe potential should remain south of this area. Otherwise, refer to the previous outlook below for more forecast details, and MCD 1511 for short term severe information across IA/MO. ..Leitman.. 07/02/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Tue Jul 02 2024/ ...Iowa/Missouri into Northeast Kansas and Vicinity... Elevated thunderstorms with a marginal/isolated hail threat are ongoing late this morning across eastern NE and southern IA in a low-level warm advection regime. This activity is also being aided by modest large-scale ascent associated with a subtle mid-level vorticity maximum moving eastward over the central Plains. The primary upper cyclone and related surface low will remain over central Canada today, with a cold front extending southward over the northern Plains/Upper Midwest and continuing southwestward into the central Plains. An effective warm front extends northeastward from a secondary surface low in north-central KS across northern MO into southern IA. This boundary will likely serve as a focus for severe thunderstorms this afternoon and evening as it attempts to lift further northward into IA. The 12Z sounding from TOP showed a very moist boundary layer, with precipitable water values through the column greater than 2 inches and somewhat steepened mid-level lapse rates. Robust daytime heating of this airmass along/south of the front will likely aid the development of moderate to strong instability by mid afternoon, even though mid-level temperature remain somewhat warm. A belt of stronger (40-55 kt) southwesterly mid-level flow associated with the subtle central Plains shortwave trough will likely overspread the frontal zone across IA and northern MO in the same time frame. With sufficient veering/strengthening of the wind field with height through mid-levels, around 35-50 kt of deep-layer shear is expected to promote organized convection, including the potential for both supercells and a bowing cluster. Thunderstorms should intensify by early to mid afternoon near the front across southeast NE/northeast KS into southern/central IA and perhaps northern MO. If this initial development can remain at least semi-discrete for a few hours, then sufficient low-level shear near the warm front would support a threat for a few tornadoes. Isolated severe hail may also occur with any sustained supercell. Otherwise, upscale growth into an MCS by mid to late afternoon appears likely given the mainly linear/frontal forcing and mid-level flow aligned mostly parallel to the surface front. Scattered to numerous damaging winds generally ranging 60-70 mph should become the primary severe hazard by late afternoon and early evening across IA and northern MO, but embedded QLCS circulations will also be possible. Convection should tend to weaken later this evening as it approaches the MS River and encounters a less unstable airmass. ...Southern/Central Plains... Additional convection should develop along the front with southwestward extent into KS and the southern/central High Plains. Given a well-mixed boundary layer and steepened low-level lapse rates with daytime heating, isolated to scattered severe/damaging winds should be the main threat with this activity. Modest low-level upslope flow in the post-frontal regime may encourage the development of isolated supercells across parts of southeast CO and vicinity. Occasional large hail and severe wind gusts may occur with any intense convection that can persist, but confidence in a small bowing cluster developing from this activity this evening remains low. Other occasionally strong to severe convection may develop southeastward from eastern WY into western NE this afternoon and evening. Weaker instability across this region should keep the overall severe threat rather isolated. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue Jul 02 2024 Valid 022000Z - 031200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN IOWA...NORTHERN MISSOURI...NORTHEAST KANSAS...AND FAR SOUTHEAST NEBRASKA... ...SUMMARY... Scattered to numerous damaging thunderstorm winds, a few tornadoes, and occasional large hail appear most likely this afternoon and early evening over parts of southern/central Iowa, northern Missouri, and northeastern Kansas. ...20z Update... The Marginal (level 1 of 5) risk has been removed from much of NE/SD/WY in the post-frontal airmass. This area is well behind a moist axis oriented across central KS into IA, and dewpoints have generally fallen into the 40s and 50s F with only weak instability noted. Ongoing convection across western NE earlier produced gusts to around 35 kt. While some gusty wind potential will be possible with any storms across the area, overall cover and severe potential appears low. Some modest trimming of the Marginal (level 1 of 5) risk has also been done from eastern NE into northern IA and southeast MN where ongoing clouds and precipitation has largely modified the airmass such that instability is low and severe potential should remain south of this area. Otherwise, refer to the previous outlook below for more forecast details, and MCD 1511 for short term severe information across IA/MO. ..Leitman.. 07/02/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Tue Jul 02 2024/ ...Iowa/Missouri into Northeast Kansas and Vicinity... Elevated thunderstorms with a marginal/isolated hail threat are ongoing late this morning across eastern NE and southern IA in a low-level warm advection regime. This activity is also being aided by modest large-scale ascent associated with a subtle mid-level vorticity maximum moving eastward over the central Plains. The primary upper cyclone and related surface low will remain over central Canada today, with a cold front extending southward over the northern Plains/Upper Midwest and continuing southwestward into the central Plains. An effective warm front extends northeastward from a secondary surface low in north-central KS across northern MO into southern IA. This boundary will likely serve as a focus for severe thunderstorms this afternoon and evening as it attempts to lift further northward into IA. The 12Z sounding from TOP showed a very moist boundary layer, with precipitable water values through the column greater than 2 inches and somewhat steepened mid-level lapse rates. Robust daytime heating of this airmass along/south of the front will likely aid the development of moderate to strong instability by mid afternoon, even though mid-level temperature remain somewhat warm. A belt of stronger (40-55 kt) southwesterly mid-level flow associated with the subtle central Plains shortwave trough will likely overspread the frontal zone across IA and northern MO in the same time frame. With sufficient veering/strengthening of the wind field with height through mid-levels, around 35-50 kt of deep-layer shear is expected to promote organized convection, including the potential for both supercells and a bowing cluster. Thunderstorms should intensify by early to mid afternoon near the front across southeast NE/northeast KS into southern/central IA and perhaps northern MO. If this initial development can remain at least semi-discrete for a few hours, then sufficient low-level shear near the warm front would support a threat for a few tornadoes. Isolated severe hail may also occur with any sustained supercell. Otherwise, upscale growth into an MCS by mid to late afternoon appears likely given the mainly linear/frontal forcing and mid-level flow aligned mostly parallel to the surface front. Scattered to numerous damaging winds generally ranging 60-70 mph should become the primary severe hazard by late afternoon and early evening across IA and northern MO, but embedded QLCS circulations will also be possible. Convection should tend to weaken later this evening as it approaches the MS River and encounters a less unstable airmass. ...Southern/Central Plains... Additional convection should develop along the front with southwestward extent into KS and the southern/central High Plains. Given a well-mixed boundary layer and steepened low-level lapse rates with daytime heating, isolated to scattered severe/damaging winds should be the main threat with this activity. Modest low-level upslope flow in the post-frontal regime may encourage the development of isolated supercells across parts of southeast CO and vicinity. Occasional large hail and severe wind gusts may occur with any intense convection that can persist, but confidence in a small bowing cluster developing from this activity this evening remains low. Other occasionally strong to severe convection may develop southeastward from eastern WY into western NE this afternoon and evening. Weaker instability across this region should keep the overall severe threat rather isolated. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue Jul 02 2024 Valid 022000Z - 031200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN IOWA...NORTHERN MISSOURI...NORTHEAST KANSAS...AND FAR SOUTHEAST NEBRASKA... ...SUMMARY... Scattered to numerous damaging thunderstorm winds, a few tornadoes, and occasional large hail appear most likely this afternoon and early evening over parts of southern/central Iowa, northern Missouri, and northeastern Kansas. ...20z Update... The Marginal (level 1 of 5) risk has been removed from much of NE/SD/WY in the post-frontal airmass. This area is well behind a moist axis oriented across central KS into IA, and dewpoints have generally fallen into the 40s and 50s F with only weak instability noted. Ongoing convection across western NE earlier produced gusts to around 35 kt. While some gusty wind potential will be possible with any storms across the area, overall cover and severe potential appears low. Some modest trimming of the Marginal (level 1 of 5) risk has also been done from eastern NE into northern IA and southeast MN where ongoing clouds and precipitation has largely modified the airmass such that instability is low and severe potential should remain south of this area. Otherwise, refer to the previous outlook below for more forecast details, and MCD 1511 for short term severe information across IA/MO. ..Leitman.. 07/02/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Tue Jul 02 2024/ ...Iowa/Missouri into Northeast Kansas and Vicinity... Elevated thunderstorms with a marginal/isolated hail threat are ongoing late this morning across eastern NE and southern IA in a low-level warm advection regime. This activity is also being aided by modest large-scale ascent associated with a subtle mid-level vorticity maximum moving eastward over the central Plains. The primary upper cyclone and related surface low will remain over central Canada today, with a cold front extending southward over the northern Plains/Upper Midwest and continuing southwestward into the central Plains. An effective warm front extends northeastward from a secondary surface low in north-central KS across northern MO into southern IA. This boundary will likely serve as a focus for severe thunderstorms this afternoon and evening as it attempts to lift further northward into IA. The 12Z sounding from TOP showed a very moist boundary layer, with precipitable water values through the column greater than 2 inches and somewhat steepened mid-level lapse rates. Robust daytime heating of this airmass along/south of the front will likely aid the development of moderate to strong instability by mid afternoon, even though mid-level temperature remain somewhat warm. A belt of stronger (40-55 kt) southwesterly mid-level flow associated with the subtle central Plains shortwave trough will likely overspread the frontal zone across IA and northern MO in the same time frame. With sufficient veering/strengthening of the wind field with height through mid-levels, around 35-50 kt of deep-layer shear is expected to promote organized convection, including the potential for both supercells and a bowing cluster. Thunderstorms should intensify by early to mid afternoon near the front across southeast NE/northeast KS into southern/central IA and perhaps northern MO. If this initial development can remain at least semi-discrete for a few hours, then sufficient low-level shear near the warm front would support a threat for a few tornadoes. Isolated severe hail may also occur with any sustained supercell. Otherwise, upscale growth into an MCS by mid to late afternoon appears likely given the mainly linear/frontal forcing and mid-level flow aligned mostly parallel to the surface front. Scattered to numerous damaging winds generally ranging 60-70 mph should become the primary severe hazard by late afternoon and early evening across IA and northern MO, but embedded QLCS circulations will also be possible. Convection should tend to weaken later this evening as it approaches the MS River and encounters a less unstable airmass. ...Southern/Central Plains... Additional convection should develop along the front with southwestward extent into KS and the southern/central High Plains. Given a well-mixed boundary layer and steepened low-level lapse rates with daytime heating, isolated to scattered severe/damaging winds should be the main threat with this activity. Modest low-level upslope flow in the post-frontal regime may encourage the development of isolated supercells across parts of southeast CO and vicinity. Occasional large hail and severe wind gusts may occur with any intense convection that can persist, but confidence in a small bowing cluster developing from this activity this evening remains low. Other occasionally strong to severe convection may develop southeastward from eastern WY into western NE this afternoon and evening. Weaker instability across this region should keep the overall severe threat rather isolated. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue Jul 02 2024 Valid 022000Z - 031200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN IOWA...NORTHERN MISSOURI...NORTHEAST KANSAS...AND FAR SOUTHEAST NEBRASKA... ...SUMMARY... Scattered to numerous damaging thunderstorm winds, a few tornadoes, and occasional large hail appear most likely this afternoon and early evening over parts of southern/central Iowa, northern Missouri, and northeastern Kansas. ...20z Update... The Marginal (level 1 of 5) risk has been removed from much of NE/SD/WY in the post-frontal airmass. This area is well behind a moist axis oriented across central KS into IA, and dewpoints have generally fallen into the 40s and 50s F with only weak instability noted. Ongoing convection across western NE earlier produced gusts to around 35 kt. While some gusty wind potential will be possible with any storms across the area, overall cover and severe potential appears low. Some modest trimming of the Marginal (level 1 of 5) risk has also been done from eastern NE into northern IA and southeast MN where ongoing clouds and precipitation has largely modified the airmass such that instability is low and severe potential should remain south of this area. Otherwise, refer to the previous outlook below for more forecast details, and MCD 1511 for short term severe information across IA/MO. ..Leitman.. 07/02/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Tue Jul 02 2024/ ...Iowa/Missouri into Northeast Kansas and Vicinity... Elevated thunderstorms with a marginal/isolated hail threat are ongoing late this morning across eastern NE and southern IA in a low-level warm advection regime. This activity is also being aided by modest large-scale ascent associated with a subtle mid-level vorticity maximum moving eastward over the central Plains. The primary upper cyclone and related surface low will remain over central Canada today, with a cold front extending southward over the northern Plains/Upper Midwest and continuing southwestward into the central Plains. An effective warm front extends northeastward from a secondary surface low in north-central KS across northern MO into southern IA. This boundary will likely serve as a focus for severe thunderstorms this afternoon and evening as it attempts to lift further northward into IA. The 12Z sounding from TOP showed a very moist boundary layer, with precipitable water values through the column greater than 2 inches and somewhat steepened mid-level lapse rates. Robust daytime heating of this airmass along/south of the front will likely aid the development of moderate to strong instability by mid afternoon, even though mid-level temperature remain somewhat warm. A belt of stronger (40-55 kt) southwesterly mid-level flow associated with the subtle central Plains shortwave trough will likely overspread the frontal zone across IA and northern MO in the same time frame. With sufficient veering/strengthening of the wind field with height through mid-levels, around 35-50 kt of deep-layer shear is expected to promote organized convection, including the potential for both supercells and a bowing cluster. Thunderstorms should intensify by early to mid afternoon near the front across southeast NE/northeast KS into southern/central IA and perhaps northern MO. If this initial development can remain at least semi-discrete for a few hours, then sufficient low-level shear near the warm front would support a threat for a few tornadoes. Isolated severe hail may also occur with any sustained supercell. Otherwise, upscale growth into an MCS by mid to late afternoon appears likely given the mainly linear/frontal forcing and mid-level flow aligned mostly parallel to the surface front. Scattered to numerous damaging winds generally ranging 60-70 mph should become the primary severe hazard by late afternoon and early evening across IA and northern MO, but embedded QLCS circulations will also be possible. Convection should tend to weaken later this evening as it approaches the MS River and encounters a less unstable airmass. ...Southern/Central Plains... Additional convection should develop along the front with southwestward extent into KS and the southern/central High Plains. Given a well-mixed boundary layer and steepened low-level lapse rates with daytime heating, isolated to scattered severe/damaging winds should be the main threat with this activity. Modest low-level upslope flow in the post-frontal regime may encourage the development of isolated supercells across parts of southeast CO and vicinity. Occasional large hail and severe wind gusts may occur with any intense convection that can persist, but confidence in a small bowing cluster developing from this activity this evening remains low. Other occasionally strong to severe convection may develop southeastward from eastern WY into western NE this afternoon and evening. Weaker instability across this region should keep the overall severe threat rather isolated. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue Jul 02 2024 Valid 022000Z - 031200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN IOWA...NORTHERN MISSOURI...NORTHEAST KANSAS...AND FAR SOUTHEAST NEBRASKA... ...SUMMARY... Scattered to numerous damaging thunderstorm winds, a few tornadoes, and occasional large hail appear most likely this afternoon and early evening over parts of southern/central Iowa, northern Missouri, and northeastern Kansas. ...20z Update... The Marginal (level 1 of 5) risk has been removed from much of NE/SD/WY in the post-frontal airmass. This area is well behind a moist axis oriented across central KS into IA, and dewpoints have generally fallen into the 40s and 50s F with only weak instability noted. Ongoing convection across western NE earlier produced gusts to around 35 kt. While some gusty wind potential will be possible with any storms across the area, overall cover and severe potential appears low. Some modest trimming of the Marginal (level 1 of 5) risk has also been done from eastern NE into northern IA and southeast MN where ongoing clouds and precipitation has largely modified the airmass such that instability is low and severe potential should remain south of this area. Otherwise, refer to the previous outlook below for more forecast details, and MCD 1511 for short term severe information across IA/MO. ..Leitman.. 07/02/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Tue Jul 02 2024/ ...Iowa/Missouri into Northeast Kansas and Vicinity... Elevated thunderstorms with a marginal/isolated hail threat are ongoing late this morning across eastern NE and southern IA in a low-level warm advection regime. This activity is also being aided by modest large-scale ascent associated with a subtle mid-level vorticity maximum moving eastward over the central Plains. The primary upper cyclone and related surface low will remain over central Canada today, with a cold front extending southward over the northern Plains/Upper Midwest and continuing southwestward into the central Plains. An effective warm front extends northeastward from a secondary surface low in north-central KS across northern MO into southern IA. This boundary will likely serve as a focus for severe thunderstorms this afternoon and evening as it attempts to lift further northward into IA. The 12Z sounding from TOP showed a very moist boundary layer, with precipitable water values through the column greater than 2 inches and somewhat steepened mid-level lapse rates. Robust daytime heating of this airmass along/south of the front will likely aid the development of moderate to strong instability by mid afternoon, even though mid-level temperature remain somewhat warm. A belt of stronger (40-55 kt) southwesterly mid-level flow associated with the subtle central Plains shortwave trough will likely overspread the frontal zone across IA and northern MO in the same time frame. With sufficient veering/strengthening of the wind field with height through mid-levels, around 35-50 kt of deep-layer shear is expected to promote organized convection, including the potential for both supercells and a bowing cluster. Thunderstorms should intensify by early to mid afternoon near the front across southeast NE/northeast KS into southern/central IA and perhaps northern MO. If this initial development can remain at least semi-discrete for a few hours, then sufficient low-level shear near the warm front would support a threat for a few tornadoes. Isolated severe hail may also occur with any sustained supercell. Otherwise, upscale growth into an MCS by mid to late afternoon appears likely given the mainly linear/frontal forcing and mid-level flow aligned mostly parallel to the surface front. Scattered to numerous damaging winds generally ranging 60-70 mph should become the primary severe hazard by late afternoon and early evening across IA and northern MO, but embedded QLCS circulations will also be possible. Convection should tend to weaken later this evening as it approaches the MS River and encounters a less unstable airmass. ...Southern/Central Plains... Additional convection should develop along the front with southwestward extent into KS and the southern/central High Plains. Given a well-mixed boundary layer and steepened low-level lapse rates with daytime heating, isolated to scattered severe/damaging winds should be the main threat with this activity. Modest low-level upslope flow in the post-frontal regime may encourage the development of isolated supercells across parts of southeast CO and vicinity. Occasional large hail and severe wind gusts may occur with any intense convection that can persist, but confidence in a small bowing cluster developing from this activity this evening remains low. Other occasionally strong to severe convection may develop southeastward from eastern WY into western NE this afternoon and evening. Weaker instability across this region should keep the overall severe threat rather isolated. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue Jul 02 2024 Valid 022000Z - 031200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN IOWA...NORTHERN MISSOURI...NORTHEAST KANSAS...AND FAR SOUTHEAST NEBRASKA... ...SUMMARY... Scattered to numerous damaging thunderstorm winds, a few tornadoes, and occasional large hail appear most likely this afternoon and early evening over parts of southern/central Iowa, northern Missouri, and northeastern Kansas. ...20z Update... The Marginal (level 1 of 5) risk has been removed from much of NE/SD/WY in the post-frontal airmass. This area is well behind a moist axis oriented across central KS into IA, and dewpoints have generally fallen into the 40s and 50s F with only weak instability noted. Ongoing convection across western NE earlier produced gusts to around 35 kt. While some gusty wind potential will be possible with any storms across the area, overall cover and severe potential appears low. Some modest trimming of the Marginal (level 1 of 5) risk has also been done from eastern NE into northern IA and southeast MN where ongoing clouds and precipitation has largely modified the airmass such that instability is low and severe potential should remain south of this area. Otherwise, refer to the previous outlook below for more forecast details, and MCD 1511 for short term severe information across IA/MO. ..Leitman.. 07/02/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Tue Jul 02 2024/ ...Iowa/Missouri into Northeast Kansas and Vicinity... Elevated thunderstorms with a marginal/isolated hail threat are ongoing late this morning across eastern NE and southern IA in a low-level warm advection regime. This activity is also being aided by modest large-scale ascent associated with a subtle mid-level vorticity maximum moving eastward over the central Plains. The primary upper cyclone and related surface low will remain over central Canada today, with a cold front extending southward over the northern Plains/Upper Midwest and continuing southwestward into the central Plains. An effective warm front extends northeastward from a secondary surface low in north-central KS across northern MO into southern IA. This boundary will likely serve as a focus for severe thunderstorms this afternoon and evening as it attempts to lift further northward into IA. The 12Z sounding from TOP showed a very moist boundary layer, with precipitable water values through the column greater than 2 inches and somewhat steepened mid-level lapse rates. Robust daytime heating of this airmass along/south of the front will likely aid the development of moderate to strong instability by mid afternoon, even though mid-level temperature remain somewhat warm. A belt of stronger (40-55 kt) southwesterly mid-level flow associated with the subtle central Plains shortwave trough will likely overspread the frontal zone across IA and northern MO in the same time frame. With sufficient veering/strengthening of the wind field with height through mid-levels, around 35-50 kt of deep-layer shear is expected to promote organized convection, including the potential for both supercells and a bowing cluster. Thunderstorms should intensify by early to mid afternoon near the front across southeast NE/northeast KS into southern/central IA and perhaps northern MO. If this initial development can remain at least semi-discrete for a few hours, then sufficient low-level shear near the warm front would support a threat for a few tornadoes. Isolated severe hail may also occur with any sustained supercell. Otherwise, upscale growth into an MCS by mid to late afternoon appears likely given the mainly linear/frontal forcing and mid-level flow aligned mostly parallel to the surface front. Scattered to numerous damaging winds generally ranging 60-70 mph should become the primary severe hazard by late afternoon and early evening across IA and northern MO, but embedded QLCS circulations will also be possible. Convection should tend to weaken later this evening as it approaches the MS River and encounters a less unstable airmass. ...Southern/Central Plains... Additional convection should develop along the front with southwestward extent into KS and the southern/central High Plains. Given a well-mixed boundary layer and steepened low-level lapse rates with daytime heating, isolated to scattered severe/damaging winds should be the main threat with this activity. Modest low-level upslope flow in the post-frontal regime may encourage the development of isolated supercells across parts of southeast CO and vicinity. Occasional large hail and severe wind gusts may occur with any intense convection that can persist, but confidence in a small bowing cluster developing from this activity this evening remains low. Other occasionally strong to severe convection may develop southeastward from eastern WY into western NE this afternoon and evening. Weaker instability across this region should keep the overall severe threat rather isolated. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue Jul 02 2024 Valid 022000Z - 031200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN IOWA...NORTHERN MISSOURI...NORTHEAST KANSAS...AND FAR SOUTHEAST NEBRASKA... ...SUMMARY... Scattered to numerous damaging thunderstorm winds, a few tornadoes, and occasional large hail appear most likely this afternoon and early evening over parts of southern/central Iowa, northern Missouri, and northeastern Kansas. ...20z Update... The Marginal (level 1 of 5) risk has been removed from much of NE/SD/WY in the post-frontal airmass. This area is well behind a moist axis oriented across central KS into IA, and dewpoints have generally fallen into the 40s and 50s F with only weak instability noted. Ongoing convection across western NE earlier produced gusts to around 35 kt. While some gusty wind potential will be possible with any storms across the area, overall cover and severe potential appears low. Some modest trimming of the Marginal (level 1 of 5) risk has also been done from eastern NE into northern IA and southeast MN where ongoing clouds and precipitation has largely modified the airmass such that instability is low and severe potential should remain south of this area. Otherwise, refer to the previous outlook below for more forecast details, and MCD 1511 for short term severe information across IA/MO. ..Leitman.. 07/02/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Tue Jul 02 2024/ ...Iowa/Missouri into Northeast Kansas and Vicinity... Elevated thunderstorms with a marginal/isolated hail threat are ongoing late this morning across eastern NE and southern IA in a low-level warm advection regime. This activity is also being aided by modest large-scale ascent associated with a subtle mid-level vorticity maximum moving eastward over the central Plains. The primary upper cyclone and related surface low will remain over central Canada today, with a cold front extending southward over the northern Plains/Upper Midwest and continuing southwestward into the central Plains. An effective warm front extends northeastward from a secondary surface low in north-central KS across northern MO into southern IA. This boundary will likely serve as a focus for severe thunderstorms this afternoon and evening as it attempts to lift further northward into IA. The 12Z sounding from TOP showed a very moist boundary layer, with precipitable water values through the column greater than 2 inches and somewhat steepened mid-level lapse rates. Robust daytime heating of this airmass along/south of the front will likely aid the development of moderate to strong instability by mid afternoon, even though mid-level temperature remain somewhat warm. A belt of stronger (40-55 kt) southwesterly mid-level flow associated with the subtle central Plains shortwave trough will likely overspread the frontal zone across IA and northern MO in the same time frame. With sufficient veering/strengthening of the wind field with height through mid-levels, around 35-50 kt of deep-layer shear is expected to promote organized convection, including the potential for both supercells and a bowing cluster. Thunderstorms should intensify by early to mid afternoon near the front across southeast NE/northeast KS into southern/central IA and perhaps northern MO. If this initial development can remain at least semi-discrete for a few hours, then sufficient low-level shear near the warm front would support a threat for a few tornadoes. Isolated severe hail may also occur with any sustained supercell. Otherwise, upscale growth into an MCS by mid to late afternoon appears likely given the mainly linear/frontal forcing and mid-level flow aligned mostly parallel to the surface front. Scattered to numerous damaging winds generally ranging 60-70 mph should become the primary severe hazard by late afternoon and early evening across IA and northern MO, but embedded QLCS circulations will also be possible. Convection should tend to weaken later this evening as it approaches the MS River and encounters a less unstable airmass. ...Southern/Central Plains... Additional convection should develop along the front with southwestward extent into KS and the southern/central High Plains. Given a well-mixed boundary layer and steepened low-level lapse rates with daytime heating, isolated to scattered severe/damaging winds should be the main threat with this activity. Modest low-level upslope flow in the post-frontal regime may encourage the development of isolated supercells across parts of southeast CO and vicinity. Occasional large hail and severe wind gusts may occur with any intense convection that can persist, but confidence in a small bowing cluster developing from this activity this evening remains low. Other occasionally strong to severe convection may develop southeastward from eastern WY into western NE this afternoon and evening. Weaker instability across this region should keep the overall severe threat rather isolated. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue Jul 02 2024 Valid 022000Z - 031200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN IOWA...NORTHERN MISSOURI...NORTHEAST KANSAS...AND FAR SOUTHEAST NEBRASKA... ...SUMMARY... Scattered to numerous damaging thunderstorm winds, a few tornadoes, and occasional large hail appear most likely this afternoon and early evening over parts of southern/central Iowa, northern Missouri, and northeastern Kansas. ...20z Update... The Marginal (level 1 of 5) risk has been removed from much of NE/SD/WY in the post-frontal airmass. This area is well behind a moist axis oriented across central KS into IA, and dewpoints have generally fallen into the 40s and 50s F with only weak instability noted. Ongoing convection across western NE earlier produced gusts to around 35 kt. While some gusty wind potential will be possible with any storms across the area, overall cover and severe potential appears low. Some modest trimming of the Marginal (level 1 of 5) risk has also been done from eastern NE into northern IA and southeast MN where ongoing clouds and precipitation has largely modified the airmass such that instability is low and severe potential should remain south of this area. Otherwise, refer to the previous outlook below for more forecast details, and MCD 1511 for short term severe information across IA/MO. ..Leitman.. 07/02/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Tue Jul 02 2024/ ...Iowa/Missouri into Northeast Kansas and Vicinity... Elevated thunderstorms with a marginal/isolated hail threat are ongoing late this morning across eastern NE and southern IA in a low-level warm advection regime. This activity is also being aided by modest large-scale ascent associated with a subtle mid-level vorticity maximum moving eastward over the central Plains. The primary upper cyclone and related surface low will remain over central Canada today, with a cold front extending southward over the northern Plains/Upper Midwest and continuing southwestward into the central Plains. An effective warm front extends northeastward from a secondary surface low in north-central KS across northern MO into southern IA. This boundary will likely serve as a focus for severe thunderstorms this afternoon and evening as it attempts to lift further northward into IA. The 12Z sounding from TOP showed a very moist boundary layer, with precipitable water values through the column greater than 2 inches and somewhat steepened mid-level lapse rates. Robust daytime heating of this airmass along/south of the front will likely aid the development of moderate to strong instability by mid afternoon, even though mid-level temperature remain somewhat warm. A belt of stronger (40-55 kt) southwesterly mid-level flow associated with the subtle central Plains shortwave trough will likely overspread the frontal zone across IA and northern MO in the same time frame. With sufficient veering/strengthening of the wind field with height through mid-levels, around 35-50 kt of deep-layer shear is expected to promote organized convection, including the potential for both supercells and a bowing cluster. Thunderstorms should intensify by early to mid afternoon near the front across southeast NE/northeast KS into southern/central IA and perhaps northern MO. If this initial development can remain at least semi-discrete for a few hours, then sufficient low-level shear near the warm front would support a threat for a few tornadoes. Isolated severe hail may also occur with any sustained supercell. Otherwise, upscale growth into an MCS by mid to late afternoon appears likely given the mainly linear/frontal forcing and mid-level flow aligned mostly parallel to the surface front. Scattered to numerous damaging winds generally ranging 60-70 mph should become the primary severe hazard by late afternoon and early evening across IA and northern MO, but embedded QLCS circulations will also be possible. Convection should tend to weaken later this evening as it approaches the MS River and encounters a less unstable airmass. ...Southern/Central Plains... Additional convection should develop along the front with southwestward extent into KS and the southern/central High Plains. Given a well-mixed boundary layer and steepened low-level lapse rates with daytime heating, isolated to scattered severe/damaging winds should be the main threat with this activity. Modest low-level upslope flow in the post-frontal regime may encourage the development of isolated supercells across parts of southeast CO and vicinity. Occasional large hail and severe wind gusts may occur with any intense convection that can persist, but confidence in a small bowing cluster developing from this activity this evening remains low. Other occasionally strong to severe convection may develop southeastward from eastern WY into western NE this afternoon and evening. Weaker instability across this region should keep the overall severe threat rather isolated. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue Jul 02 2024 Valid 022000Z - 031200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN IOWA...NORTHERN MISSOURI...NORTHEAST KANSAS...AND FAR SOUTHEAST NEBRASKA... ...SUMMARY... Scattered to numerous damaging thunderstorm winds, a few tornadoes, and occasional large hail appear most likely this afternoon and early evening over parts of southern/central Iowa, northern Missouri, and northeastern Kansas. ...20z Update... The Marginal (level 1 of 5) risk has been removed from much of NE/SD/WY in the post-frontal airmass. This area is well behind a moist axis oriented across central KS into IA, and dewpoints have generally fallen into the 40s and 50s F with only weak instability noted. Ongoing convection across western NE earlier produced gusts to around 35 kt. While some gusty wind potential will be possible with any storms across the area, overall cover and severe potential appears low. Some modest trimming of the Marginal (level 1 of 5) risk has also been done from eastern NE into northern IA and southeast MN where ongoing clouds and precipitation has largely modified the airmass such that instability is low and severe potential should remain south of this area. Otherwise, refer to the previous outlook below for more forecast details, and MCD 1511 for short term severe information across IA/MO. ..Leitman.. 07/02/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Tue Jul 02 2024/ ...Iowa/Missouri into Northeast Kansas and Vicinity... Elevated thunderstorms with a marginal/isolated hail threat are ongoing late this morning across eastern NE and southern IA in a low-level warm advection regime. This activity is also being aided by modest large-scale ascent associated with a subtle mid-level vorticity maximum moving eastward over the central Plains. The primary upper cyclone and related surface low will remain over central Canada today, with a cold front extending southward over the northern Plains/Upper Midwest and continuing southwestward into the central Plains. An effective warm front extends northeastward from a secondary surface low in north-central KS across northern MO into southern IA. This boundary will likely serve as a focus for severe thunderstorms this afternoon and evening as it attempts to lift further northward into IA. The 12Z sounding from TOP showed a very moist boundary layer, with precipitable water values through the column greater than 2 inches and somewhat steepened mid-level lapse rates. Robust daytime heating of this airmass along/south of the front will likely aid the development of moderate to strong instability by mid afternoon, even though mid-level temperature remain somewhat warm. A belt of stronger (40-55 kt) southwesterly mid-level flow associated with the subtle central Plains shortwave trough will likely overspread the frontal zone across IA and northern MO in the same time frame. With sufficient veering/strengthening of the wind field with height through mid-levels, around 35-50 kt of deep-layer shear is expected to promote organized convection, including the potential for both supercells and a bowing cluster. Thunderstorms should intensify by early to mid afternoon near the front across southeast NE/northeast KS into southern/central IA and perhaps northern MO. If this initial development can remain at least semi-discrete for a few hours, then sufficient low-level shear near the warm front would support a threat for a few tornadoes. Isolated severe hail may also occur with any sustained supercell. Otherwise, upscale growth into an MCS by mid to late afternoon appears likely given the mainly linear/frontal forcing and mid-level flow aligned mostly parallel to the surface front. Scattered to numerous damaging winds generally ranging 60-70 mph should become the primary severe hazard by late afternoon and early evening across IA and northern MO, but embedded QLCS circulations will also be possible. Convection should tend to weaken later this evening as it approaches the MS River and encounters a less unstable airmass. ...Southern/Central Plains... Additional convection should develop along the front with southwestward extent into KS and the southern/central High Plains. Given a well-mixed boundary layer and steepened low-level lapse rates with daytime heating, isolated to scattered severe/damaging winds should be the main threat with this activity. Modest low-level upslope flow in the post-frontal regime may encourage the development of isolated supercells across parts of southeast CO and vicinity. Occasional large hail and severe wind gusts may occur with any intense convection that can persist, but confidence in a small bowing cluster developing from this activity this evening remains low. Other occasionally strong to severe convection may develop southeastward from eastern WY into western NE this afternoon and evening. Weaker instability across this region should keep the overall severe threat rather isolated. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue Jul 02 2024 Valid 022000Z - 031200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN IOWA...NORTHERN MISSOURI...NORTHEAST KANSAS...AND FAR SOUTHEAST NEBRASKA... ...SUMMARY... Scattered to numerous damaging thunderstorm winds, a few tornadoes, and occasional large hail appear most likely this afternoon and early evening over parts of southern/central Iowa, northern Missouri, and northeastern Kansas. ...20z Update... The Marginal (level 1 of 5) risk has been removed from much of NE/SD/WY in the post-frontal airmass. This area is well behind a moist axis oriented across central KS into IA, and dewpoints have generally fallen into the 40s and 50s F with only weak instability noted. Ongoing convection across western NE earlier produced gusts to around 35 kt. While some gusty wind potential will be possible with any storms across the area, overall cover and severe potential appears low. Some modest trimming of the Marginal (level 1 of 5) risk has also been done from eastern NE into northern IA and southeast MN where ongoing clouds and precipitation has largely modified the airmass such that instability is low and severe potential should remain south of this area. Otherwise, refer to the previous outlook below for more forecast details, and MCD 1511 for short term severe information across IA/MO. ..Leitman.. 07/02/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Tue Jul 02 2024/ ...Iowa/Missouri into Northeast Kansas and Vicinity... Elevated thunderstorms with a marginal/isolated hail threat are ongoing late this morning across eastern NE and southern IA in a low-level warm advection regime. This activity is also being aided by modest large-scale ascent associated with a subtle mid-level vorticity maximum moving eastward over the central Plains. The primary upper cyclone and related surface low will remain over central Canada today, with a cold front extending southward over the northern Plains/Upper Midwest and continuing southwestward into the central Plains. An effective warm front extends northeastward from a secondary surface low in north-central KS across northern MO into southern IA. This boundary will likely serve as a focus for severe thunderstorms this afternoon and evening as it attempts to lift further northward into IA. The 12Z sounding from TOP showed a very moist boundary layer, with precipitable water values through the column greater than 2 inches and somewhat steepened mid-level lapse rates. Robust daytime heating of this airmass along/south of the front will likely aid the development of moderate to strong instability by mid afternoon, even though mid-level temperature remain somewhat warm. A belt of stronger (40-55 kt) southwesterly mid-level flow associated with the subtle central Plains shortwave trough will likely overspread the frontal zone across IA and northern MO in the same time frame. With sufficient veering/strengthening of the wind field with height through mid-levels, around 35-50 kt of deep-layer shear is expected to promote organized convection, including the potential for both supercells and a bowing cluster. Thunderstorms should intensify by early to mid afternoon near the front across southeast NE/northeast KS into southern/central IA and perhaps northern MO. If this initial development can remain at least semi-discrete for a few hours, then sufficient low-level shear near the warm front would support a threat for a few tornadoes. Isolated severe hail may also occur with any sustained supercell. Otherwise, upscale growth into an MCS by mid to late afternoon appears likely given the mainly linear/frontal forcing and mid-level flow aligned mostly parallel to the surface front. Scattered to numerous damaging winds generally ranging 60-70 mph should become the primary severe hazard by late afternoon and early evening across IA and northern MO, but embedded QLCS circulations will also be possible. Convection should tend to weaken later this evening as it approaches the MS River and encounters a less unstable airmass. ...Southern/Central Plains... Additional convection should develop along the front with southwestward extent into KS and the southern/central High Plains. Given a well-mixed boundary layer and steepened low-level lapse rates with daytime heating, isolated to scattered severe/damaging winds should be the main threat with this activity. Modest low-level upslope flow in the post-frontal regime may encourage the development of isolated supercells across parts of southeast CO and vicinity. Occasional large hail and severe wind gusts may occur with any intense convection that can persist, but confidence in a small bowing cluster developing from this activity this evening remains low. Other occasionally strong to severe convection may develop southeastward from eastern WY into western NE this afternoon and evening. Weaker instability across this region should keep the overall severe threat rather isolated. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue Jul 02 2024 Valid 022000Z - 031200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN IOWA...NORTHERN MISSOURI...NORTHEAST KANSAS...AND FAR SOUTHEAST NEBRASKA... ...SUMMARY... Scattered to numerous damaging thunderstorm winds, a few tornadoes, and occasional large hail appear most likely this afternoon and early evening over parts of southern/central Iowa, northern Missouri, and northeastern Kansas. ...20z Update... The Marginal (level 1 of 5) risk has been removed from much of NE/SD/WY in the post-frontal airmass. This area is well behind a moist axis oriented across central KS into IA, and dewpoints have generally fallen into the 40s and 50s F with only weak instability noted. Ongoing convection across western NE earlier produced gusts to around 35 kt. While some gusty wind potential will be possible with any storms across the area, overall cover and severe potential appears low. Some modest trimming of the Marginal (level 1 of 5) risk has also been done from eastern NE into northern IA and southeast MN where ongoing clouds and precipitation has largely modified the airmass such that instability is low and severe potential should remain south of this area. Otherwise, refer to the previous outlook below for more forecast details, and MCD 1511 for short term severe information across IA/MO. ..Leitman.. 07/02/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Tue Jul 02 2024/ ...Iowa/Missouri into Northeast Kansas and Vicinity... Elevated thunderstorms with a marginal/isolated hail threat are ongoing late this morning across eastern NE and southern IA in a low-level warm advection regime. This activity is also being aided by modest large-scale ascent associated with a subtle mid-level vorticity maximum moving eastward over the central Plains. The primary upper cyclone and related surface low will remain over central Canada today, with a cold front extending southward over the northern Plains/Upper Midwest and continuing southwestward into the central Plains. An effective warm front extends northeastward from a secondary surface low in north-central KS across northern MO into southern IA. This boundary will likely serve as a focus for severe thunderstorms this afternoon and evening as it attempts to lift further northward into IA. The 12Z sounding from TOP showed a very moist boundary layer, with precipitable water values through the column greater than 2 inches and somewhat steepened mid-level lapse rates. Robust daytime heating of this airmass along/south of the front will likely aid the development of moderate to strong instability by mid afternoon, even though mid-level temperature remain somewhat warm. A belt of stronger (40-55 kt) southwesterly mid-level flow associated with the subtle central Plains shortwave trough will likely overspread the frontal zone across IA and northern MO in the same time frame. With sufficient veering/strengthening of the wind field with height through mid-levels, around 35-50 kt of deep-layer shear is expected to promote organized convection, including the potential for both supercells and a bowing cluster. Thunderstorms should intensify by early to mid afternoon near the front across southeast NE/northeast KS into southern/central IA and perhaps northern MO. If this initial development can remain at least semi-discrete for a few hours, then sufficient low-level shear near the warm front would support a threat for a few tornadoes. Isolated severe hail may also occur with any sustained supercell. Otherwise, upscale growth into an MCS by mid to late afternoon appears likely given the mainly linear/frontal forcing and mid-level flow aligned mostly parallel to the surface front. Scattered to numerous damaging winds generally ranging 60-70 mph should become the primary severe hazard by late afternoon and early evening across IA and northern MO, but embedded QLCS circulations will also be possible. Convection should tend to weaken later this evening as it approaches the MS River and encounters a less unstable airmass. ...Southern/Central Plains... Additional convection should develop along the front with southwestward extent into KS and the southern/central High Plains. Given a well-mixed boundary layer and steepened low-level lapse rates with daytime heating, isolated to scattered severe/damaging winds should be the main threat with this activity. Modest low-level upslope flow in the post-frontal regime may encourage the development of isolated supercells across parts of southeast CO and vicinity. Occasional large hail and severe wind gusts may occur with any intense convection that can persist, but confidence in a small bowing cluster developing from this activity this evening remains low. Other occasionally strong to severe convection may develop southeastward from eastern WY into western NE this afternoon and evening. Weaker instability across this region should keep the overall severe threat rather isolated. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue Jul 02 2024 Valid 022000Z - 031200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN IOWA...NORTHERN MISSOURI...NORTHEAST KANSAS...AND FAR SOUTHEAST NEBRASKA... ...SUMMARY... Scattered to numerous damaging thunderstorm winds, a few tornadoes, and occasional large hail appear most likely this afternoon and early evening over parts of southern/central Iowa, northern Missouri, and northeastern Kansas. ...20z Update... The Marginal (level 1 of 5) risk has been removed from much of NE/SD/WY in the post-frontal airmass. This area is well behind a moist axis oriented across central KS into IA, and dewpoints have generally fallen into the 40s and 50s F with only weak instability noted. Ongoing convection across western NE earlier produced gusts to around 35 kt. While some gusty wind potential will be possible with any storms across the area, overall cover and severe potential appears low. Some modest trimming of the Marginal (level 1 of 5) risk has also been done from eastern NE into northern IA and southeast MN where ongoing clouds and precipitation has largely modified the airmass such that instability is low and severe potential should remain south of this area. Otherwise, refer to the previous outlook below for more forecast details, and MCD 1511 for short term severe information across IA/MO. ..Leitman.. 07/02/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Tue Jul 02 2024/ ...Iowa/Missouri into Northeast Kansas and Vicinity... Elevated thunderstorms with a marginal/isolated hail threat are ongoing late this morning across eastern NE and southern IA in a low-level warm advection regime. This activity is also being aided by modest large-scale ascent associated with a subtle mid-level vorticity maximum moving eastward over the central Plains. The primary upper cyclone and related surface low will remain over central Canada today, with a cold front extending southward over the northern Plains/Upper Midwest and continuing southwestward into the central Plains. An effective warm front extends northeastward from a secondary surface low in north-central KS across northern MO into southern IA. This boundary will likely serve as a focus for severe thunderstorms this afternoon and evening as it attempts to lift further northward into IA. The 12Z sounding from TOP showed a very moist boundary layer, with precipitable water values through the column greater than 2 inches and somewhat steepened mid-level lapse rates. Robust daytime heating of this airmass along/south of the front will likely aid the development of moderate to strong instability by mid afternoon, even though mid-level temperature remain somewhat warm. A belt of stronger (40-55 kt) southwesterly mid-level flow associated with the subtle central Plains shortwave trough will likely overspread the frontal zone across IA and northern MO in the same time frame. With sufficient veering/strengthening of the wind field with height through mid-levels, around 35-50 kt of deep-layer shear is expected to promote organized convection, including the potential for both supercells and a bowing cluster. Thunderstorms should intensify by early to mid afternoon near the front across southeast NE/northeast KS into southern/central IA and perhaps northern MO. If this initial development can remain at least semi-discrete for a few hours, then sufficient low-level shear near the warm front would support a threat for a few tornadoes. Isolated severe hail may also occur with any sustained supercell. Otherwise, upscale growth into an MCS by mid to late afternoon appears likely given the mainly linear/frontal forcing and mid-level flow aligned mostly parallel to the surface front. Scattered to numerous damaging winds generally ranging 60-70 mph should become the primary severe hazard by late afternoon and early evening across IA and northern MO, but embedded QLCS circulations will also be possible. Convection should tend to weaken later this evening as it approaches the MS River and encounters a less unstable airmass. ...Southern/Central Plains... Additional convection should develop along the front with southwestward extent into KS and the southern/central High Plains. Given a well-mixed boundary layer and steepened low-level lapse rates with daytime heating, isolated to scattered severe/damaging winds should be the main threat with this activity. Modest low-level upslope flow in the post-frontal regime may encourage the development of isolated supercells across parts of southeast CO and vicinity. Occasional large hail and severe wind gusts may occur with any intense convection that can persist, but confidence in a small bowing cluster developing from this activity this evening remains low. Other occasionally strong to severe convection may develop southeastward from eastern WY into western NE this afternoon and evening. Weaker instability across this region should keep the overall severe threat rather isolated. Read more