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SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Tue Apr 16 2024 Valid 162000Z - 171200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE MIDWEST AND MIDDLE MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are likely today, especially across northern Missouri, Iowa, and northwestern Illinois. Large hail, damaging winds, and tornadoes are expected. More isolated activity could develop as far south as the Ozarks and Mid-South. ...Synopsis... The previous forecast largely remains on track with only minor modifications made to reflect convective trends across portions of NE, KS, and western MO. Recent analyses show that the best kinematic environment resides from central AR into MO and southern/southeast IA. However, thermodynamic limitations (largely due to warm temperatures in the 850-700 mb as sampled by the 18 UTC DVN and 19 UTC ILX soundings and modest mid-level lapse rates) and unfavorable storm interactions have modulated convective intensity/organization thus far. Further intensification remains possible through the afternoon/early evening amid peak diurnal heating (see MCD 460 for additional near-term details). Across far eastern NE into western IA, cold temperatures aloft (supporting surface-based lifted indices between -7 to -9 C) combined with plentiful ambient low-level vorticity along surface boundaries continues to support a tornado threat. See MCD 461 for additional details. ..Moore.. 04/16/2024 .PREV DISCUSSION... /ISSUED 1140 AM CDT Tue Apr 16 2024/ ...Midwest/Middle Mississippi Valley... Regenerative scattered showers and thunderstorms continue to occur across western/northern Missouri into much of Iowa at late morning, originating with a warm sector that narrows with north-northwestward extent into southern Iowa and far east/northeast Nebraska in vicinity of the surface low. Even while warm-sector cloud breaks have been limited, steady early-spring heating and low-level moistening is occurring with surface dewpoints rising through the lower 60s F. This development coincides with an intense/cyclonically curved 90+ kt polar jet and a low-level jet that will remain diurnally strong (40+ kt). Modest cloud breaks aside, destabilization will be further aided by a pocket of steep mid-level lapse rates and cold temperatures aloft on the southeast side of the upper trough/low. Scenario supports a risk for supercells especially across northern Missouri into southern/eastern Iowa and northwest Illinois. Steep mid-level lapse rates will aid in hail production, with a few golf ball or 2+ inch diameter stones possible with the more robust cores. Tornadoes will also be a concern, as the enhanced boundary-layer flow and enlarged/curved hodographs associated with the low-level jet will aid in updraft rotation. The main tornado potential is still expected to be focused along/near the warm front in southern/eastern Iowa where the stronger low-level shear is forecast. A strong (EF2+) tornado is possible. Isolated to scattered damaging winds are otherwise expected regionally. Farther south toward the Ozarks and Mid-South, a potential for at least isolated severe thunderstorms remains apparent into this evening, with a moist/confluent regime near/ahead of the eastward-advancing front. Mid-level lapse rates will remain limited. However, steady low-level moistening will tend to counteract a tendency for nocturnal boundary cooling, netting a scenario with limited warm-sector inhibition tonight, supporting the possibility of supercells capable of all severe hazards including a tornado risk, even if severe storms remain relatively isolated overall. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Tue Apr 16 2024 Valid 162000Z - 171200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE MIDWEST AND MIDDLE MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are likely today, especially across northern Missouri, Iowa, and northwestern Illinois. Large hail, damaging winds, and tornadoes are expected. More isolated activity could develop as far south as the Ozarks and Mid-South. ...Synopsis... The previous forecast largely remains on track with only minor modifications made to reflect convective trends across portions of NE, KS, and western MO. Recent analyses show that the best kinematic environment resides from central AR into MO and southern/southeast IA. However, thermodynamic limitations (largely due to warm temperatures in the 850-700 mb as sampled by the 18 UTC DVN and 19 UTC ILX soundings and modest mid-level lapse rates) and unfavorable storm interactions have modulated convective intensity/organization thus far. Further intensification remains possible through the afternoon/early evening amid peak diurnal heating (see MCD 460 for additional near-term details). Across far eastern NE into western IA, cold temperatures aloft (supporting surface-based lifted indices between -7 to -9 C) combined with plentiful ambient low-level vorticity along surface boundaries continues to support a tornado threat. See MCD 461 for additional details. ..Moore.. 04/16/2024 .PREV DISCUSSION... /ISSUED 1140 AM CDT Tue Apr 16 2024/ ...Midwest/Middle Mississippi Valley... Regenerative scattered showers and thunderstorms continue to occur across western/northern Missouri into much of Iowa at late morning, originating with a warm sector that narrows with north-northwestward extent into southern Iowa and far east/northeast Nebraska in vicinity of the surface low. Even while warm-sector cloud breaks have been limited, steady early-spring heating and low-level moistening is occurring with surface dewpoints rising through the lower 60s F. This development coincides with an intense/cyclonically curved 90+ kt polar jet and a low-level jet that will remain diurnally strong (40+ kt). Modest cloud breaks aside, destabilization will be further aided by a pocket of steep mid-level lapse rates and cold temperatures aloft on the southeast side of the upper trough/low. Scenario supports a risk for supercells especially across northern Missouri into southern/eastern Iowa and northwest Illinois. Steep mid-level lapse rates will aid in hail production, with a few golf ball or 2+ inch diameter stones possible with the more robust cores. Tornadoes will also be a concern, as the enhanced boundary-layer flow and enlarged/curved hodographs associated with the low-level jet will aid in updraft rotation. The main tornado potential is still expected to be focused along/near the warm front in southern/eastern Iowa where the stronger low-level shear is forecast. A strong (EF2+) tornado is possible. Isolated to scattered damaging winds are otherwise expected regionally. Farther south toward the Ozarks and Mid-South, a potential for at least isolated severe thunderstorms remains apparent into this evening, with a moist/confluent regime near/ahead of the eastward-advancing front. Mid-level lapse rates will remain limited. However, steady low-level moistening will tend to counteract a tendency for nocturnal boundary cooling, netting a scenario with limited warm-sector inhibition tonight, supporting the possibility of supercells capable of all severe hazards including a tornado risk, even if severe storms remain relatively isolated overall. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Tue Apr 16 2024 Valid 162000Z - 171200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE MIDWEST AND MIDDLE MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are likely today, especially across northern Missouri, Iowa, and northwestern Illinois. Large hail, damaging winds, and tornadoes are expected. More isolated activity could develop as far south as the Ozarks and Mid-South. ...Synopsis... The previous forecast largely remains on track with only minor modifications made to reflect convective trends across portions of NE, KS, and western MO. Recent analyses show that the best kinematic environment resides from central AR into MO and southern/southeast IA. However, thermodynamic limitations (largely due to warm temperatures in the 850-700 mb as sampled by the 18 UTC DVN and 19 UTC ILX soundings and modest mid-level lapse rates) and unfavorable storm interactions have modulated convective intensity/organization thus far. Further intensification remains possible through the afternoon/early evening amid peak diurnal heating (see MCD 460 for additional near-term details). Across far eastern NE into western IA, cold temperatures aloft (supporting surface-based lifted indices between -7 to -9 C) combined with plentiful ambient low-level vorticity along surface boundaries continues to support a tornado threat. See MCD 461 for additional details. ..Moore.. 04/16/2024 .PREV DISCUSSION... /ISSUED 1140 AM CDT Tue Apr 16 2024/ ...Midwest/Middle Mississippi Valley... Regenerative scattered showers and thunderstorms continue to occur across western/northern Missouri into much of Iowa at late morning, originating with a warm sector that narrows with north-northwestward extent into southern Iowa and far east/northeast Nebraska in vicinity of the surface low. Even while warm-sector cloud breaks have been limited, steady early-spring heating and low-level moistening is occurring with surface dewpoints rising through the lower 60s F. This development coincides with an intense/cyclonically curved 90+ kt polar jet and a low-level jet that will remain diurnally strong (40+ kt). Modest cloud breaks aside, destabilization will be further aided by a pocket of steep mid-level lapse rates and cold temperatures aloft on the southeast side of the upper trough/low. Scenario supports a risk for supercells especially across northern Missouri into southern/eastern Iowa and northwest Illinois. Steep mid-level lapse rates will aid in hail production, with a few golf ball or 2+ inch diameter stones possible with the more robust cores. Tornadoes will also be a concern, as the enhanced boundary-layer flow and enlarged/curved hodographs associated with the low-level jet will aid in updraft rotation. The main tornado potential is still expected to be focused along/near the warm front in southern/eastern Iowa where the stronger low-level shear is forecast. A strong (EF2+) tornado is possible. Isolated to scattered damaging winds are otherwise expected regionally. Farther south toward the Ozarks and Mid-South, a potential for at least isolated severe thunderstorms remains apparent into this evening, with a moist/confluent regime near/ahead of the eastward-advancing front. Mid-level lapse rates will remain limited. However, steady low-level moistening will tend to counteract a tendency for nocturnal boundary cooling, netting a scenario with limited warm-sector inhibition tonight, supporting the possibility of supercells capable of all severe hazards including a tornado risk, even if severe storms remain relatively isolated overall. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Tue Apr 16 2024 Valid 162000Z - 171200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE MIDWEST AND MIDDLE MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are likely today, especially across northern Missouri, Iowa, and northwestern Illinois. Large hail, damaging winds, and tornadoes are expected. More isolated activity could develop as far south as the Ozarks and Mid-South. ...Synopsis... The previous forecast largely remains on track with only minor modifications made to reflect convective trends across portions of NE, KS, and western MO. Recent analyses show that the best kinematic environment resides from central AR into MO and southern/southeast IA. However, thermodynamic limitations (largely due to warm temperatures in the 850-700 mb as sampled by the 18 UTC DVN and 19 UTC ILX soundings and modest mid-level lapse rates) and unfavorable storm interactions have modulated convective intensity/organization thus far. Further intensification remains possible through the afternoon/early evening amid peak diurnal heating (see MCD 460 for additional near-term details). Across far eastern NE into western IA, cold temperatures aloft (supporting surface-based lifted indices between -7 to -9 C) combined with plentiful ambient low-level vorticity along surface boundaries continues to support a tornado threat. See MCD 461 for additional details. ..Moore.. 04/16/2024 .PREV DISCUSSION... /ISSUED 1140 AM CDT Tue Apr 16 2024/ ...Midwest/Middle Mississippi Valley... Regenerative scattered showers and thunderstorms continue to occur across western/northern Missouri into much of Iowa at late morning, originating with a warm sector that narrows with north-northwestward extent into southern Iowa and far east/northeast Nebraska in vicinity of the surface low. Even while warm-sector cloud breaks have been limited, steady early-spring heating and low-level moistening is occurring with surface dewpoints rising through the lower 60s F. This development coincides with an intense/cyclonically curved 90+ kt polar jet and a low-level jet that will remain diurnally strong (40+ kt). Modest cloud breaks aside, destabilization will be further aided by a pocket of steep mid-level lapse rates and cold temperatures aloft on the southeast side of the upper trough/low. Scenario supports a risk for supercells especially across northern Missouri into southern/eastern Iowa and northwest Illinois. Steep mid-level lapse rates will aid in hail production, with a few golf ball or 2+ inch diameter stones possible with the more robust cores. Tornadoes will also be a concern, as the enhanced boundary-layer flow and enlarged/curved hodographs associated with the low-level jet will aid in updraft rotation. The main tornado potential is still expected to be focused along/near the warm front in southern/eastern Iowa where the stronger low-level shear is forecast. A strong (EF2+) tornado is possible. Isolated to scattered damaging winds are otherwise expected regionally. Farther south toward the Ozarks and Mid-South, a potential for at least isolated severe thunderstorms remains apparent into this evening, with a moist/confluent regime near/ahead of the eastward-advancing front. Mid-level lapse rates will remain limited. However, steady low-level moistening will tend to counteract a tendency for nocturnal boundary cooling, netting a scenario with limited warm-sector inhibition tonight, supporting the possibility of supercells capable of all severe hazards including a tornado risk, even if severe storms remain relatively isolated overall. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Tue Apr 16 2024 Valid 162000Z - 171200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE MIDWEST AND MIDDLE MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are likely today, especially across northern Missouri, Iowa, and northwestern Illinois. Large hail, damaging winds, and tornadoes are expected. More isolated activity could develop as far south as the Ozarks and Mid-South. ...Synopsis... The previous forecast largely remains on track with only minor modifications made to reflect convective trends across portions of NE, KS, and western MO. Recent analyses show that the best kinematic environment resides from central AR into MO and southern/southeast IA. However, thermodynamic limitations (largely due to warm temperatures in the 850-700 mb as sampled by the 18 UTC DVN and 19 UTC ILX soundings and modest mid-level lapse rates) and unfavorable storm interactions have modulated convective intensity/organization thus far. Further intensification remains possible through the afternoon/early evening amid peak diurnal heating (see MCD 460 for additional near-term details). Across far eastern NE into western IA, cold temperatures aloft (supporting surface-based lifted indices between -7 to -9 C) combined with plentiful ambient low-level vorticity along surface boundaries continues to support a tornado threat. See MCD 461 for additional details. ..Moore.. 04/16/2024 .PREV DISCUSSION... /ISSUED 1140 AM CDT Tue Apr 16 2024/ ...Midwest/Middle Mississippi Valley... Regenerative scattered showers and thunderstorms continue to occur across western/northern Missouri into much of Iowa at late morning, originating with a warm sector that narrows with north-northwestward extent into southern Iowa and far east/northeast Nebraska in vicinity of the surface low. Even while warm-sector cloud breaks have been limited, steady early-spring heating and low-level moistening is occurring with surface dewpoints rising through the lower 60s F. This development coincides with an intense/cyclonically curved 90+ kt polar jet and a low-level jet that will remain diurnally strong (40+ kt). Modest cloud breaks aside, destabilization will be further aided by a pocket of steep mid-level lapse rates and cold temperatures aloft on the southeast side of the upper trough/low. Scenario supports a risk for supercells especially across northern Missouri into southern/eastern Iowa and northwest Illinois. Steep mid-level lapse rates will aid in hail production, with a few golf ball or 2+ inch diameter stones possible with the more robust cores. Tornadoes will also be a concern, as the enhanced boundary-layer flow and enlarged/curved hodographs associated with the low-level jet will aid in updraft rotation. The main tornado potential is still expected to be focused along/near the warm front in southern/eastern Iowa where the stronger low-level shear is forecast. A strong (EF2+) tornado is possible. Isolated to scattered damaging winds are otherwise expected regionally. Farther south toward the Ozarks and Mid-South, a potential for at least isolated severe thunderstorms remains apparent into this evening, with a moist/confluent regime near/ahead of the eastward-advancing front. Mid-level lapse rates will remain limited. However, steady low-level moistening will tend to counteract a tendency for nocturnal boundary cooling, netting a scenario with limited warm-sector inhibition tonight, supporting the possibility of supercells capable of all severe hazards including a tornado risk, even if severe storms remain relatively isolated overall. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Tue Apr 16 2024 Valid 162000Z - 171200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE MIDWEST AND MIDDLE MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are likely today, especially across northern Missouri, Iowa, and northwestern Illinois. Large hail, damaging winds, and tornadoes are expected. More isolated activity could develop as far south as the Ozarks and Mid-South. ...Synopsis... The previous forecast largely remains on track with only minor modifications made to reflect convective trends across portions of NE, KS, and western MO. Recent analyses show that the best kinematic environment resides from central AR into MO and southern/southeast IA. However, thermodynamic limitations (largely due to warm temperatures in the 850-700 mb as sampled by the 18 UTC DVN and 19 UTC ILX soundings and modest mid-level lapse rates) and unfavorable storm interactions have modulated convective intensity/organization thus far. Further intensification remains possible through the afternoon/early evening amid peak diurnal heating (see MCD 460 for additional near-term details). Across far eastern NE into western IA, cold temperatures aloft (supporting surface-based lifted indices between -7 to -9 C) combined with plentiful ambient low-level vorticity along surface boundaries continues to support a tornado threat. See MCD 461 for additional details. ..Moore.. 04/16/2024 .PREV DISCUSSION... /ISSUED 1140 AM CDT Tue Apr 16 2024/ ...Midwest/Middle Mississippi Valley... Regenerative scattered showers and thunderstorms continue to occur across western/northern Missouri into much of Iowa at late morning, originating with a warm sector that narrows with north-northwestward extent into southern Iowa and far east/northeast Nebraska in vicinity of the surface low. Even while warm-sector cloud breaks have been limited, steady early-spring heating and low-level moistening is occurring with surface dewpoints rising through the lower 60s F. This development coincides with an intense/cyclonically curved 90+ kt polar jet and a low-level jet that will remain diurnally strong (40+ kt). Modest cloud breaks aside, destabilization will be further aided by a pocket of steep mid-level lapse rates and cold temperatures aloft on the southeast side of the upper trough/low. Scenario supports a risk for supercells especially across northern Missouri into southern/eastern Iowa and northwest Illinois. Steep mid-level lapse rates will aid in hail production, with a few golf ball or 2+ inch diameter stones possible with the more robust cores. Tornadoes will also be a concern, as the enhanced boundary-layer flow and enlarged/curved hodographs associated with the low-level jet will aid in updraft rotation. The main tornado potential is still expected to be focused along/near the warm front in southern/eastern Iowa where the stronger low-level shear is forecast. A strong (EF2+) tornado is possible. Isolated to scattered damaging winds are otherwise expected regionally. Farther south toward the Ozarks and Mid-South, a potential for at least isolated severe thunderstorms remains apparent into this evening, with a moist/confluent regime near/ahead of the eastward-advancing front. Mid-level lapse rates will remain limited. However, steady low-level moistening will tend to counteract a tendency for nocturnal boundary cooling, netting a scenario with limited warm-sector inhibition tonight, supporting the possibility of supercells capable of all severe hazards including a tornado risk, even if severe storms remain relatively isolated overall. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Tue Apr 16 2024 Valid 162000Z - 171200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE MIDWEST AND MIDDLE MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are likely today, especially across northern Missouri, Iowa, and northwestern Illinois. Large hail, damaging winds, and tornadoes are expected. More isolated activity could develop as far south as the Ozarks and Mid-South. ...Synopsis... The previous forecast largely remains on track with only minor modifications made to reflect convective trends across portions of NE, KS, and western MO. Recent analyses show that the best kinematic environment resides from central AR into MO and southern/southeast IA. However, thermodynamic limitations (largely due to warm temperatures in the 850-700 mb as sampled by the 18 UTC DVN and 19 UTC ILX soundings and modest mid-level lapse rates) and unfavorable storm interactions have modulated convective intensity/organization thus far. Further intensification remains possible through the afternoon/early evening amid peak diurnal heating (see MCD 460 for additional near-term details). Across far eastern NE into western IA, cold temperatures aloft (supporting surface-based lifted indices between -7 to -9 C) combined with plentiful ambient low-level vorticity along surface boundaries continues to support a tornado threat. See MCD 461 for additional details. ..Moore.. 04/16/2024 .PREV DISCUSSION... /ISSUED 1140 AM CDT Tue Apr 16 2024/ ...Midwest/Middle Mississippi Valley... Regenerative scattered showers and thunderstorms continue to occur across western/northern Missouri into much of Iowa at late morning, originating with a warm sector that narrows with north-northwestward extent into southern Iowa and far east/northeast Nebraska in vicinity of the surface low. Even while warm-sector cloud breaks have been limited, steady early-spring heating and low-level moistening is occurring with surface dewpoints rising through the lower 60s F. This development coincides with an intense/cyclonically curved 90+ kt polar jet and a low-level jet that will remain diurnally strong (40+ kt). Modest cloud breaks aside, destabilization will be further aided by a pocket of steep mid-level lapse rates and cold temperatures aloft on the southeast side of the upper trough/low. Scenario supports a risk for supercells especially across northern Missouri into southern/eastern Iowa and northwest Illinois. Steep mid-level lapse rates will aid in hail production, with a few golf ball or 2+ inch diameter stones possible with the more robust cores. Tornadoes will also be a concern, as the enhanced boundary-layer flow and enlarged/curved hodographs associated with the low-level jet will aid in updraft rotation. The main tornado potential is still expected to be focused along/near the warm front in southern/eastern Iowa where the stronger low-level shear is forecast. A strong (EF2+) tornado is possible. Isolated to scattered damaging winds are otherwise expected regionally. Farther south toward the Ozarks and Mid-South, a potential for at least isolated severe thunderstorms remains apparent into this evening, with a moist/confluent regime near/ahead of the eastward-advancing front. Mid-level lapse rates will remain limited. However, steady low-level moistening will tend to counteract a tendency for nocturnal boundary cooling, netting a scenario with limited warm-sector inhibition tonight, supporting the possibility of supercells capable of all severe hazards including a tornado risk, even if severe storms remain relatively isolated overall. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Tue Apr 16 2024 Valid 162000Z - 171200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE MIDWEST AND MIDDLE MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are likely today, especially across northern Missouri, Iowa, and northwestern Illinois. Large hail, damaging winds, and tornadoes are expected. More isolated activity could develop as far south as the Ozarks and Mid-South. ...Synopsis... The previous forecast largely remains on track with only minor modifications made to reflect convective trends across portions of NE, KS, and western MO. Recent analyses show that the best kinematic environment resides from central AR into MO and southern/southeast IA. However, thermodynamic limitations (largely due to warm temperatures in the 850-700 mb as sampled by the 18 UTC DVN and 19 UTC ILX soundings and modest mid-level lapse rates) and unfavorable storm interactions have modulated convective intensity/organization thus far. Further intensification remains possible through the afternoon/early evening amid peak diurnal heating (see MCD 460 for additional near-term details). Across far eastern NE into western IA, cold temperatures aloft (supporting surface-based lifted indices between -7 to -9 C) combined with plentiful ambient low-level vorticity along surface boundaries continues to support a tornado threat. See MCD 461 for additional details. ..Moore.. 04/16/2024 .PREV DISCUSSION... /ISSUED 1140 AM CDT Tue Apr 16 2024/ ...Midwest/Middle Mississippi Valley... Regenerative scattered showers and thunderstorms continue to occur across western/northern Missouri into much of Iowa at late morning, originating with a warm sector that narrows with north-northwestward extent into southern Iowa and far east/northeast Nebraska in vicinity of the surface low. Even while warm-sector cloud breaks have been limited, steady early-spring heating and low-level moistening is occurring with surface dewpoints rising through the lower 60s F. This development coincides with an intense/cyclonically curved 90+ kt polar jet and a low-level jet that will remain diurnally strong (40+ kt). Modest cloud breaks aside, destabilization will be further aided by a pocket of steep mid-level lapse rates and cold temperatures aloft on the southeast side of the upper trough/low. Scenario supports a risk for supercells especially across northern Missouri into southern/eastern Iowa and northwest Illinois. Steep mid-level lapse rates will aid in hail production, with a few golf ball or 2+ inch diameter stones possible with the more robust cores. Tornadoes will also be a concern, as the enhanced boundary-layer flow and enlarged/curved hodographs associated with the low-level jet will aid in updraft rotation. The main tornado potential is still expected to be focused along/near the warm front in southern/eastern Iowa where the stronger low-level shear is forecast. A strong (EF2+) tornado is possible. Isolated to scattered damaging winds are otherwise expected regionally. Farther south toward the Ozarks and Mid-South, a potential for at least isolated severe thunderstorms remains apparent into this evening, with a moist/confluent regime near/ahead of the eastward-advancing front. Mid-level lapse rates will remain limited. However, steady low-level moistening will tend to counteract a tendency for nocturnal boundary cooling, netting a scenario with limited warm-sector inhibition tonight, supporting the possibility of supercells capable of all severe hazards including a tornado risk, even if severe storms remain relatively isolated overall. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Tue Apr 16 2024 Valid 162000Z - 171200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE MIDWEST AND MIDDLE MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe thunderstorms are likely today, especially across northern Missouri, Iowa, and northwestern Illinois. Large hail, damaging winds, and tornadoes are expected. More isolated activity could develop as far south as the Ozarks and Mid-South. ...Synopsis... The previous forecast largely remains on track with only minor modifications made to reflect convective trends across portions of NE, KS, and western MO. Recent analyses show that the best kinematic environment resides from central AR into MO and southern/southeast IA. However, thermodynamic limitations (largely due to warm temperatures in the 850-700 mb as sampled by the 18 UTC DVN and 19 UTC ILX soundings and modest mid-level lapse rates) and unfavorable storm interactions have modulated convective intensity/organization thus far. Further intensification remains possible through the afternoon/early evening amid peak diurnal heating (see MCD 460 for additional near-term details). Across far eastern NE into western IA, cold temperatures aloft (supporting surface-based lifted indices between -7 to -9 C) combined with plentiful ambient low-level vorticity along surface boundaries continues to support a tornado threat. See MCD 461 for additional details. ..Moore.. 04/16/2024 .PREV DISCUSSION... /ISSUED 1140 AM CDT Tue Apr 16 2024/ ...Midwest/Middle Mississippi Valley... Regenerative scattered showers and thunderstorms continue to occur across western/northern Missouri into much of Iowa at late morning, originating with a warm sector that narrows with north-northwestward extent into southern Iowa and far east/northeast Nebraska in vicinity of the surface low. Even while warm-sector cloud breaks have been limited, steady early-spring heating and low-level moistening is occurring with surface dewpoints rising through the lower 60s F. This development coincides with an intense/cyclonically curved 90+ kt polar jet and a low-level jet that will remain diurnally strong (40+ kt). Modest cloud breaks aside, destabilization will be further aided by a pocket of steep mid-level lapse rates and cold temperatures aloft on the southeast side of the upper trough/low. Scenario supports a risk for supercells especially across northern Missouri into southern/eastern Iowa and northwest Illinois. Steep mid-level lapse rates will aid in hail production, with a few golf ball or 2+ inch diameter stones possible with the more robust cores. Tornadoes will also be a concern, as the enhanced boundary-layer flow and enlarged/curved hodographs associated with the low-level jet will aid in updraft rotation. The main tornado potential is still expected to be focused along/near the warm front in southern/eastern Iowa where the stronger low-level shear is forecast. A strong (EF2+) tornado is possible. Isolated to scattered damaging winds are otherwise expected regionally. Farther south toward the Ozarks and Mid-South, a potential for at least isolated severe thunderstorms remains apparent into this evening, with a moist/confluent regime near/ahead of the eastward-advancing front. Mid-level lapse rates will remain limited. However, steady low-level moistening will tend to counteract a tendency for nocturnal boundary cooling, netting a scenario with limited warm-sector inhibition tonight, supporting the possibility of supercells capable of all severe hazards including a tornado risk, even if severe storms remain relatively isolated overall. Read more

MD 0460 CONCERNING TORNADO WATCH 116...117... FOR NORTHERN MISSOURI INTO CENTRAL/EASTERN IOWA...NORTHWEST ILLINOIS AND EXTREME SOUTHWEST WISCONSIN
Mesoscale Discussion 0460 NWS Storm Prediction Center Norman OK 0156 PM CDT Tue Apr 16 2024 Areas affected...northern Missouri into central/eastern Iowa...northwest Illinois and extreme southwest Wisconsin Concerning...Tornado Watch 116...117... Valid 161856Z - 162000Z The severe weather threat for Tornado Watch 116, 117 continues. SUMMARY...All severe hazards remain possible across parts of northern Missouri, central/eastern Iowa, northwest Illinois and extreme southwest Wisconsin the next several hours. DISCUSSION...A couple of bands of severe thunderstorms will continue to generally shift east/northeast the next few hours over the MCD area. The leading band of convection will continue to exhibit a mix of storm modes (cells and cluster/line segments) as weak inhibition remains downstream. Nevertheless, low 60s F dewpoints and favorable low-level shear will support rotating storms and a couple of tornadoes remain possible. Behind the leading band of convection, across north-central MO, low to mid 60s F dewpoints are still in place amid an uncapped environment. As large scale ascent continues to overspread the area, and on the edges of the midlevel dryslot, these storms may experience some intensification in the next couple of hours. However, contamination of the airmass by the leading band of storms may also be a limiting factor, and there is quite a bit of uncertainty regarding the evolution of the second band of storms. Furthermore, midlevel lapse rates and instability across the area remain somewhat modest, which is likely resulting in some stunting of updrafts intensity despite strong vertical shear profiles. Overall, all severe hazards remain possible, though uncertainty remains higher than usual. ..Leitman.. 04/16/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ILX...LSX...DVN...ARX...DMX...EAX... LAT...LON 42979180 41918967 40058975 39059053 38939167 38719332 38769421 40009395 41799337 42759332 43019265 42979180 Read more

WW 0118 Status Updates
STATUS REPORT ON WW 118 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..BENTLEY..04/16/24 ATTN...WFO...DMX...FSD...OAX... STATUS REPORT FOR WT 118 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS IAC009-021-025-027-035-041-047-059-063-073-077-081-085-091-093- 109-119-133-141-143-147-149-151-161-165-167-187-189-193-195- 162040- IA . IOWA COUNTIES INCLUDED ARE AUDUBON BUENA VISTA CALHOUN CARROLL CHEROKEE CLAY CRAWFORD DICKINSON EMMET GREENE GUTHRIE HANCOCK HARRISON HUMBOLDT IDA KOSSUTH LYON MONONA O'BRIEN OSCEOLA PALO ALTO PLYMOUTH POCAHONTAS SAC SHELBY SIOUX WEBSTER WINNEBAGO WOODBURY WORTH NEC021-027-039-043-051-119-167-173-179-162040- NE . NEBRASKA COUNTIES INCLUDED ARE BURT CEDAR CUMING DAKOTA DIXON MADISON Read more

WW 0117 Status Updates
STATUS REPORT ON WW 117 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0460. ..LEITMAN..04/16/24 ATTN...WFO...DVN...ARX...LSX...ILX... STATUS REPORT FOR WT 117 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC001-009-011-015-017-057-067-071-073-085-095-109-123-125-131- 137-143-149-155-161-169-171-175-187-195-162040- IL . ILLINOIS COUNTIES INCLUDED ARE ADAMS BROWN BUREAU CARROLL CASS FULTON HANCOCK HENDERSON HENRY JO DAVIESS KNOX MCDONOUGH MARSHALL MASON MERCER MORGAN PEORIA PIKE PUTNAM ROCK ISLAND SCHUYLER SCOTT STARK WARREN WHITESIDE IAC011-019-031-037-043-045-055-057-061-065-067-087-095-097-101- 103-105-107-111-113-115-139-163-177-183-162040- IA . IOWA COUNTIES INCLUDED ARE BENTON BUCHANAN CEDAR Read more

WW 0116 Status Updates
STATUS REPORT ON WW 116 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 S SZL TO 25 E LWD TO 50 W DSM. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0460. ..LEITMAN..04/16/24 ATTN...WFO...DMX...EAX... STATUS REPORT FOR WT 116 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS IAC007-013-015-017-023-033-039-049-051-069-075-079-083-099-117- 121-123-125-127-135-153-157-169-171-179-181-185-197-162040- IA . IOWA COUNTIES INCLUDED ARE APPANOOSE BLACK HAWK BOONE BREMER BUTLER CERRO GORDO CLARKE DALLAS DAVIS FRANKLIN GRUNDY HAMILTON HARDIN JASPER LUCAS MADISON MAHASKA MARION MARSHALL MONROE POLK POWESHIEK STORY TAMA WAPELLO WARREN WAYNE WRIGHT MOC001-041-053-089-115-121-159-171-175-195-197-211-162040- MO . MISSOURI COUNTIES INCLUDED ARE Read more

No Mesoscale Discussions are in effect as of Tue Apr 16 18:35:03 UTC 2024.

WW 0118 Status Updates
STATUS REPORT ON WW 118 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..LEITMAN..04/16/24 ATTN...WFO...DMX...FSD...OAX... STATUS REPORT FOR WT 118 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS IAC009-021-025-027-029-035-041-047-059-063-073-077-081-085-091- 093-109-119-133-141-143-147-149-151-161-165-167-187-189-193-195- 161940- IA . IOWA COUNTIES INCLUDED ARE AUDUBON BUENA VISTA CALHOUN CARROLL CASS CHEROKEE CLAY CRAWFORD DICKINSON EMMET GREENE GUTHRIE HANCOCK HARRISON HUMBOLDT IDA KOSSUTH LYON MONONA O'BRIEN OSCEOLA PALO ALTO PLYMOUTH POCAHONTAS SAC SHELBY SIOUX WEBSTER WINNEBAGO WOODBURY WORTH NEC021-027-039-043-051-119-167-173-179-161940- NE . NEBRASKA COUNTIES INCLUDED ARE BURT CEDAR CUMING Read more

WW 0117 Status Updates
STATUS REPORT ON WW 117 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..LEITMAN..04/16/24 ATTN...WFO...DVN...ARX...LSX...ILX... STATUS REPORT FOR WT 117 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC001-009-011-015-017-057-067-071-073-085-095-109-123-125-131- 137-143-149-155-161-169-171-175-187-195-161940- IL . ILLINOIS COUNTIES INCLUDED ARE ADAMS BROWN BUREAU CARROLL CASS FULTON HANCOCK HENDERSON HENRY JO DAVIESS KNOX MCDONOUGH MARSHALL MASON MERCER MORGAN PEORIA PIKE PUTNAM ROCK ISLAND SCHUYLER SCOTT STARK WARREN WHITESIDE IAC011-019-031-037-043-045-055-057-061-065-067-087-095-097-101- 103-105-107-111-113-115-139-163-177-183-161940- IA . IOWA COUNTIES INCLUDED ARE BENTON BUCHANAN CEDAR CHICKASAW CLAYTON CLINTON DELAWARE DES MOINES DUBUQUE Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0129 PM CDT Tue Apr 16 2024 Valid 171200Z - 181200Z No changes to the ongoing forecast. ..Wendt.. 04/16/2024 .PREV DISCUSSION... /ISSUED 0200 AM CDT Tue Apr 16 2024/ ...Synopsis... In the mid levels, the flow pattern aloft is forecast to quickly de-amplify and trend more zonal as the Midwest upper low rapidly fills. Lingering strong westerly flow is likely over the southern Rockies and High Plains through Wednesday. A weak lee cyclone is expected to form over parts of eastern CO, supporting gusty surface winds to the west across parts of eastern NM. Elevated fire-weather conditions will be possible across parts of the southern High Plains. ...Southern High Plains... Elevated to brief locally critical fire-weather conditions appear possible over parts of the southern High plains/Rockies as the southeastern CO low develops on Wednesday afternoon. Winds of 15-20 mph will overlap low RH of around 10-15% atop dry fuels. Fire weather concerns are most likely near the terrain to the southwest of the surface low over eastern NM and far southern CO. Here winds and downslope drying are expected to be the strongest with the longest duration for a few hours during the afternoon. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0129 PM CDT Tue Apr 16 2024 Valid 171200Z - 181200Z No changes to the ongoing forecast. ..Wendt.. 04/16/2024 .PREV DISCUSSION... /ISSUED 0200 AM CDT Tue Apr 16 2024/ ...Synopsis... In the mid levels, the flow pattern aloft is forecast to quickly de-amplify and trend more zonal as the Midwest upper low rapidly fills. Lingering strong westerly flow is likely over the southern Rockies and High Plains through Wednesday. A weak lee cyclone is expected to form over parts of eastern CO, supporting gusty surface winds to the west across parts of eastern NM. Elevated fire-weather conditions will be possible across parts of the southern High Plains. ...Southern High Plains... Elevated to brief locally critical fire-weather conditions appear possible over parts of the southern High plains/Rockies as the southeastern CO low develops on Wednesday afternoon. Winds of 15-20 mph will overlap low RH of around 10-15% atop dry fuels. Fire weather concerns are most likely near the terrain to the southwest of the surface low over eastern NM and far southern CO. Here winds and downslope drying are expected to be the strongest with the longest duration for a few hours during the afternoon. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0129 PM CDT Tue Apr 16 2024 Valid 171200Z - 181200Z No changes to the ongoing forecast. ..Wendt.. 04/16/2024 .PREV DISCUSSION... /ISSUED 0200 AM CDT Tue Apr 16 2024/ ...Synopsis... In the mid levels, the flow pattern aloft is forecast to quickly de-amplify and trend more zonal as the Midwest upper low rapidly fills. Lingering strong westerly flow is likely over the southern Rockies and High Plains through Wednesday. A weak lee cyclone is expected to form over parts of eastern CO, supporting gusty surface winds to the west across parts of eastern NM. Elevated fire-weather conditions will be possible across parts of the southern High Plains. ...Southern High Plains... Elevated to brief locally critical fire-weather conditions appear possible over parts of the southern High plains/Rockies as the southeastern CO low develops on Wednesday afternoon. Winds of 15-20 mph will overlap low RH of around 10-15% atop dry fuels. Fire weather concerns are most likely near the terrain to the southwest of the surface low over eastern NM and far southern CO. Here winds and downslope drying are expected to be the strongest with the longest duration for a few hours during the afternoon. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0129 PM CDT Tue Apr 16 2024 Valid 171200Z - 181200Z No changes to the ongoing forecast. ..Wendt.. 04/16/2024 .PREV DISCUSSION... /ISSUED 0200 AM CDT Tue Apr 16 2024/ ...Synopsis... In the mid levels, the flow pattern aloft is forecast to quickly de-amplify and trend more zonal as the Midwest upper low rapidly fills. Lingering strong westerly flow is likely over the southern Rockies and High Plains through Wednesday. A weak lee cyclone is expected to form over parts of eastern CO, supporting gusty surface winds to the west across parts of eastern NM. Elevated fire-weather conditions will be possible across parts of the southern High Plains. ...Southern High Plains... Elevated to brief locally critical fire-weather conditions appear possible over parts of the southern High plains/Rockies as the southeastern CO low develops on Wednesday afternoon. Winds of 15-20 mph will overlap low RH of around 10-15% atop dry fuels. Fire weather concerns are most likely near the terrain to the southwest of the surface low over eastern NM and far southern CO. Here winds and downslope drying are expected to be the strongest with the longest duration for a few hours during the afternoon. ...Please see www.spc.noaa.gov/fire for graphic product... Read more