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SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0747 PM CDT Sun Apr 07 2024 Valid 080100Z - 081200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE MID-MISSISSIPPI VALLEY... ...SUMMARY... Widely scattered strong thunderstorms remain possible this evening in the lower/mid Mississippi Valley. Scattered strong to occasionally severe storms remain from western Tennessee into northern Louisiana. Expect these storms to persist for a few more hours given moderate instability and supercell wind profiles. These storms will have a threat for isolated large hail and damaging wind gusts. The threat should mostly wane by late evening as the boundary layer cools and instability decreases. ..Bentley.. 04/08/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0747 PM CDT Sun Apr 07 2024 Valid 080100Z - 081200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE MID-MISSISSIPPI VALLEY... ...SUMMARY... Widely scattered strong thunderstorms remain possible this evening in the lower/mid Mississippi Valley. Scattered strong to occasionally severe storms remain from western Tennessee into northern Louisiana. Expect these storms to persist for a few more hours given moderate instability and supercell wind profiles. These storms will have a threat for isolated large hail and damaging wind gusts. The threat should mostly wane by late evening as the boundary layer cools and instability decreases. ..Bentley.. 04/08/2024 Read more

No watches are valid as of Sun Apr 7 23:46:01 UTC 2024.

No Mesoscale Discussions are in effect as of Sun Apr 7 23:46:01 UTC 2024.

MD 0382 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR SOUTHEAST AR...NORTHEAST LA...SOUTHWEST TN...NORTHWEST MS
Mesoscale Discussion 0382 NWS Storm Prediction Center Norman OK 0520 PM CDT Sun Apr 07 2024 Areas affected...Southeast AR...Northeast LA...Southwest TN...Northwest MS Concerning...Severe potential...Watch possible Valid 072220Z - 072345Z Probability of Watch Issuance...40 percent SUMMARY...A couple of supercells may develop by early evening, with a threat of isolated hail and possibly a tornado or two. DISCUSSION...Cumulus has been gradually increasing late this afternoon from eastern AR into northern LA, in advance of a nearly stationary surface front, with recent attempts at initiation noted. Diurnal heating of a relatively moist airmass has resulted in MLCAPE increasing to 1000-1500 J/kg. With generally neutral large-scale ascent and only weak convergence near the surface boundary, storm coverage may remain rather isolated, but with favorable deep-layer shear in place, a couple of supercells could eventually evolve as storms slowly mature into early evening. With time, storms will tend to move northeastward out of the low-level moist axis, so the longevity of any severe threat is uncertain. However, some threat of isolated hail and locally gusty winds would accompany any supercells. Modestly favorable low-level shear/SRH (as noted from the KNQA VWP) could also support some tornado potential, if robust supercells can be sustained. While the threat may remain somewhat marginal, watch issuance is possible due to supercell potential. ..Dean/Hart.. 04/07/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MEG...JAN...LZK...SHV... LAT...LON 33948963 32669094 32149196 32249227 32369260 32669281 32899283 33249262 34659150 34989115 35188994 35208991 35318947 34918936 34258952 33948963 Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0438 PM CDT Sun Apr 07 2024 Valid 091200Z - 151200Z A closed low will propagate eastward across southern Arizona/southern New Mexico and into the central and southern Plains on D3-Tuesday, bringing an increase in surface winds but also potential for widespread wetting rainfall and cooler temperatures. The expected precipitation will help to moisten fuels and reduce fire weather concerns across portions of the Central/Southern Plains. Little to no rainfall is expected across portions of far western Texas, where fuels in this region will likely remain critically dry with periods of dry and breezy conditions creating Elevated to Critical fire weather. ...(D3 - Tuesday) Western Texas... As the upper-level low moves across western Texas, strong westerly flow aloft will overspread the Sierra Madre bringing further downslope warming and drying to an already very dry air mass across far western Texas into the Big Bend region. Relative humidity will drop as low as the single digits, with sustained winds approaching 20-25 mph (gusting 40-50 mph). A cold front will slide southward through the day bringing in cooler northwesterly flow, which will lead to an increase in relative humidity spreading north to south. This brings uncertainty in the duration of any potential Critical fire weather conditions, particularly on the northern fringe of the 40 percent probabilities where fuels are less sparse. As such, a trend to shift the 40 percent further south continues with this outlook. Across far western Texas into the Big Bend region eastward to the Edwards Plateau, fuels are critically dry with potential for very strong surface winds and single digit humidity. As such, a 70 percent Critical region was added with this outlook where conditions should be met for several hours. Strong post frontal northwesterly flow will overlap dry conditions along the southern Texas/Mexico border on D4 - Wednesday but coverage should remain too limited to warrant probabilities. Dry and breezy conditions will be possible across portions of eastern Colorado into western Kansas, where less rainfall is expected. However, a relatively cool continental air mass should keep relative humidity above critical thresholds. For D5 - D6 Thursday to Friday, high pressure will build across the Great Plains, keeping winds low where fuels remain dry. Late in the period D7 - D8 Saturday to Sunday, another western trough is projected to begin spreading enhanced westerly flow across the southwest into the Rockies, which may bring additional periods of fire weather concerns to the central/southern Plains as well as some drying of fuels across portions of the Desert Southwest. ..Thornton.. 04/07/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0438 PM CDT Sun Apr 07 2024 Valid 091200Z - 151200Z A closed low will propagate eastward across southern Arizona/southern New Mexico and into the central and southern Plains on D3-Tuesday, bringing an increase in surface winds but also potential for widespread wetting rainfall and cooler temperatures. The expected precipitation will help to moisten fuels and reduce fire weather concerns across portions of the Central/Southern Plains. Little to no rainfall is expected across portions of far western Texas, where fuels in this region will likely remain critically dry with periods of dry and breezy conditions creating Elevated to Critical fire weather. ...(D3 - Tuesday) Western Texas... As the upper-level low moves across western Texas, strong westerly flow aloft will overspread the Sierra Madre bringing further downslope warming and drying to an already very dry air mass across far western Texas into the Big Bend region. Relative humidity will drop as low as the single digits, with sustained winds approaching 20-25 mph (gusting 40-50 mph). A cold front will slide southward through the day bringing in cooler northwesterly flow, which will lead to an increase in relative humidity spreading north to south. This brings uncertainty in the duration of any potential Critical fire weather conditions, particularly on the northern fringe of the 40 percent probabilities where fuels are less sparse. As such, a trend to shift the 40 percent further south continues with this outlook. Across far western Texas into the Big Bend region eastward to the Edwards Plateau, fuels are critically dry with potential for very strong surface winds and single digit humidity. As such, a 70 percent Critical region was added with this outlook where conditions should be met for several hours. Strong post frontal northwesterly flow will overlap dry conditions along the southern Texas/Mexico border on D4 - Wednesday but coverage should remain too limited to warrant probabilities. Dry and breezy conditions will be possible across portions of eastern Colorado into western Kansas, where less rainfall is expected. However, a relatively cool continental air mass should keep relative humidity above critical thresholds. For D5 - D6 Thursday to Friday, high pressure will build across the Great Plains, keeping winds low where fuels remain dry. Late in the period D7 - D8 Saturday to Sunday, another western trough is projected to begin spreading enhanced westerly flow across the southwest into the Rockies, which may bring additional periods of fire weather concerns to the central/southern Plains as well as some drying of fuels across portions of the Desert Southwest. ..Thornton.. 04/07/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0438 PM CDT Sun Apr 07 2024 Valid 091200Z - 151200Z A closed low will propagate eastward across southern Arizona/southern New Mexico and into the central and southern Plains on D3-Tuesday, bringing an increase in surface winds but also potential for widespread wetting rainfall and cooler temperatures. The expected precipitation will help to moisten fuels and reduce fire weather concerns across portions of the Central/Southern Plains. Little to no rainfall is expected across portions of far western Texas, where fuels in this region will likely remain critically dry with periods of dry and breezy conditions creating Elevated to Critical fire weather. ...(D3 - Tuesday) Western Texas... As the upper-level low moves across western Texas, strong westerly flow aloft will overspread the Sierra Madre bringing further downslope warming and drying to an already very dry air mass across far western Texas into the Big Bend region. Relative humidity will drop as low as the single digits, with sustained winds approaching 20-25 mph (gusting 40-50 mph). A cold front will slide southward through the day bringing in cooler northwesterly flow, which will lead to an increase in relative humidity spreading north to south. This brings uncertainty in the duration of any potential Critical fire weather conditions, particularly on the northern fringe of the 40 percent probabilities where fuels are less sparse. As such, a trend to shift the 40 percent further south continues with this outlook. Across far western Texas into the Big Bend region eastward to the Edwards Plateau, fuels are critically dry with potential for very strong surface winds and single digit humidity. As such, a 70 percent Critical region was added with this outlook where conditions should be met for several hours. Strong post frontal northwesterly flow will overlap dry conditions along the southern Texas/Mexico border on D4 - Wednesday but coverage should remain too limited to warrant probabilities. Dry and breezy conditions will be possible across portions of eastern Colorado into western Kansas, where less rainfall is expected. However, a relatively cool continental air mass should keep relative humidity above critical thresholds. For D5 - D6 Thursday to Friday, high pressure will build across the Great Plains, keeping winds low where fuels remain dry. Late in the period D7 - D8 Saturday to Sunday, another western trough is projected to begin spreading enhanced westerly flow across the southwest into the Rockies, which may bring additional periods of fire weather concerns to the central/southern Plains as well as some drying of fuels across portions of the Desert Southwest. ..Thornton.. 04/07/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0438 PM CDT Sun Apr 07 2024 Valid 091200Z - 151200Z A closed low will propagate eastward across southern Arizona/southern New Mexico and into the central and southern Plains on D3-Tuesday, bringing an increase in surface winds but also potential for widespread wetting rainfall and cooler temperatures. The expected precipitation will help to moisten fuels and reduce fire weather concerns across portions of the Central/Southern Plains. Little to no rainfall is expected across portions of far western Texas, where fuels in this region will likely remain critically dry with periods of dry and breezy conditions creating Elevated to Critical fire weather. ...(D3 - Tuesday) Western Texas... As the upper-level low moves across western Texas, strong westerly flow aloft will overspread the Sierra Madre bringing further downslope warming and drying to an already very dry air mass across far western Texas into the Big Bend region. Relative humidity will drop as low as the single digits, with sustained winds approaching 20-25 mph (gusting 40-50 mph). A cold front will slide southward through the day bringing in cooler northwesterly flow, which will lead to an increase in relative humidity spreading north to south. This brings uncertainty in the duration of any potential Critical fire weather conditions, particularly on the northern fringe of the 40 percent probabilities where fuels are less sparse. As such, a trend to shift the 40 percent further south continues with this outlook. Across far western Texas into the Big Bend region eastward to the Edwards Plateau, fuels are critically dry with potential for very strong surface winds and single digit humidity. As such, a 70 percent Critical region was added with this outlook where conditions should be met for several hours. Strong post frontal northwesterly flow will overlap dry conditions along the southern Texas/Mexico border on D4 - Wednesday but coverage should remain too limited to warrant probabilities. Dry and breezy conditions will be possible across portions of eastern Colorado into western Kansas, where less rainfall is expected. However, a relatively cool continental air mass should keep relative humidity above critical thresholds. For D5 - D6 Thursday to Friday, high pressure will build across the Great Plains, keeping winds low where fuels remain dry. Late in the period D7 - D8 Saturday to Sunday, another western trough is projected to begin spreading enhanced westerly flow across the southwest into the Rockies, which may bring additional periods of fire weather concerns to the central/southern Plains as well as some drying of fuels across portions of the Desert Southwest. ..Thornton.. 04/07/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0438 PM CDT Sun Apr 07 2024 Valid 091200Z - 151200Z A closed low will propagate eastward across southern Arizona/southern New Mexico and into the central and southern Plains on D3-Tuesday, bringing an increase in surface winds but also potential for widespread wetting rainfall and cooler temperatures. The expected precipitation will help to moisten fuels and reduce fire weather concerns across portions of the Central/Southern Plains. Little to no rainfall is expected across portions of far western Texas, where fuels in this region will likely remain critically dry with periods of dry and breezy conditions creating Elevated to Critical fire weather. ...(D3 - Tuesday) Western Texas... As the upper-level low moves across western Texas, strong westerly flow aloft will overspread the Sierra Madre bringing further downslope warming and drying to an already very dry air mass across far western Texas into the Big Bend region. Relative humidity will drop as low as the single digits, with sustained winds approaching 20-25 mph (gusting 40-50 mph). A cold front will slide southward through the day bringing in cooler northwesterly flow, which will lead to an increase in relative humidity spreading north to south. This brings uncertainty in the duration of any potential Critical fire weather conditions, particularly on the northern fringe of the 40 percent probabilities where fuels are less sparse. As such, a trend to shift the 40 percent further south continues with this outlook. Across far western Texas into the Big Bend region eastward to the Edwards Plateau, fuels are critically dry with potential for very strong surface winds and single digit humidity. As such, a 70 percent Critical region was added with this outlook where conditions should be met for several hours. Strong post frontal northwesterly flow will overlap dry conditions along the southern Texas/Mexico border on D4 - Wednesday but coverage should remain too limited to warrant probabilities. Dry and breezy conditions will be possible across portions of eastern Colorado into western Kansas, where less rainfall is expected. However, a relatively cool continental air mass should keep relative humidity above critical thresholds. For D5 - D6 Thursday to Friday, high pressure will build across the Great Plains, keeping winds low where fuels remain dry. Late in the period D7 - D8 Saturday to Sunday, another western trough is projected to begin spreading enhanced westerly flow across the southwest into the Rockies, which may bring additional periods of fire weather concerns to the central/southern Plains as well as some drying of fuels across portions of the Desert Southwest. ..Thornton.. 04/07/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 0381 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PARTS OF SOUTHEAST MISSOURI...SOUTHERN ILLINOIS...NORTHEAST ARKANSAS AND ADJACENT PORTIONS OF WESTERN KENTUCKY/TENNESSEE
Mesoscale Discussion 0381 NWS Storm Prediction Center Norman OK 0212 PM CDT Sun Apr 07 2024 Areas affected...parts of southeast Missouri...southern Illinois...northeast Arkansas and adjacent portions of western Kentucky/Tennessee Concerning...Severe potential...Watch possible Valid 071912Z - 072145Z Probability of Watch Issuance...40 percent SUMMARY...Scattered strong thunderstorm activity is expected to continue to develop through 4-6 PM CDT. This may include the evolution of a couple widely scattered supercells, posing a risk for severe hail and potential for a tornado or two. DISCUSSION...While a weak cold front advancing eastward toward the mid/lower Mississippi Valley is becoming increasingly diffuse, a rather sharp low-level moisture gradient is being maintained along a lingering wind shift now slowly advancing across portions of east central and southeastern Missouri through central Arkansas. Ahead of the wind shift, surface dew points are increasing through the lower/mid 60s in a narrow plume across eastern Arkansas, and the leading edge of this moisture return may nose across the Missouri Bootheel into southern Illinois through 21-23Z. Although ascent associated with weak low-level warm advection within this regime continues to contribute to considerable cloud cover, breaks in the overcast are allowing for some insolation beneath the southeastern periphery of a broad pocket of cool mid-level air which has overspread much of the northern Great Plains into upper Mississippi Valley. This is contributing to weak destabilization and bands of deepening convective development. With further destabilization through late afternoon (mixed-layer CAPE forecast to exceed 500 J/kg and perhaps locally approach 1000 J/kg), convective development appears likely to continue to gradually intensify. Although wind fields to the southeast of a broad and initially deep, but filling, surface cyclone centered over northeastern Nebraska are forecast to undergo notable weakening through early evening, south-southwesterly to west-southwesterly flow in the 850-500 mb layer appears likely to remain on the order of 30-60+ kt across the destabilizing air mass. With increasing low-level inflow of unstable air, the evolution of widely scattered supercell structures seems possible by late afternoon. These may eventually become capable of producing marginally severe hail, and at least some risk for producing a tornado, before diminishing this evening. ..Kerr/Goss.. 04/07/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PAH...ILX...MEG...LSX...LZK... LAT...LON 35209125 37139059 38638966 38708832 37968820 36068891 35328989 35209125 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Sun Apr 07 2024 Valid 072000Z - 081200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE MID-MISSISSIPPI VALLEY... ...SUMMARY... Widely scattered strong/isolated severe thunderstorms remain possible late this afternoon and evening in the lower/mid Mississippi Valley. ...20Z Update... The only change made in the 20Z Day 1 Outlook update was to expand 2 percent tornado probabilities westward into far southeast SD, where adequate insolation has boosted 0-3 km CAPE to 50-100 J/kg ahead of a vertical-vorticity rich surface boundary (per 19Z mesoanalysis). Otherwise, the previous forecast remains on track, with no major changes or additions made. Please see the previous forecast below for more details. ..Squitieri.. 04/07/2024 .PREV DISCUSSION... /ISSUED 1129 AM CDT Sun Apr 07 2024/ ...Mid/lower Mississippi Valley area... While dewpoints remain in the 30s and 40s across the SLGT risk area late this morning, low-level moisture advection is ongoing ahead of the advancing cold front, with low to mid 60s dewpoints now observed across central and southern portions of Arkansas. As the front advances eastward, and the more favorable low-level theta-e airmass continues advecting northward, filtered heating will support modest destabilization, with afternoon mixed-layer CAPE values rising into the 500 to 1000 J/kg range. Stronger ascent will remain just north of the SLGT risk area, as a lobe of vorticity rotating through cyclonic southwesterly flow aloft on the southeastern side of closed upper low over Nebraska crosses Illinois/Indiana this afternoon. Still, scattered convective development is expected to begin by mid to late afternoon across the Mid Mississippi Valley, and southward into the Delta region, in focused low-level ascent near the cold front. While modest CAPE will likely limit severe potential, the deep-layer wind field (veering and increasing favorably with height across the pre-frontal warm sector) will likely augment a few of the stronger updrafts, suggesting that a few storms will become capable of producing hail and/or damaging winds. A tornado or two will also be possible, with hodographs indicating favorable helicity with any right-moving supercell. Severe potential should peak through late afternoon, and then gradually diminish this evening as the boundary layer cools, and the cold front weakens with time. ...Parts of central/southeastern Iowa and vicinity... As the weakening/vertically stacked low shifts northeastward out of Nebraska and across northwestern Iowa this afternoon, continued daytime heating of a marginally moist (40s dewpoints) boundary layer, residing beneath rather steep mid-level lapse rates will continue to facilitate weak destabilization. Thunderstorms have developed late this morning across portions of northern and central Illinois, and across north-central Iowa and into adjacent southern Minnesota. By mid afternoon, new convective development is expected along the occluded front currently moving northeastward across the Nebraska/Iowa border/Mid-Missouri Valley at this time, as it shifts into central and southeastern Iowa. While the evolving, low-topped storms should remain largely sub-severe, a strong to severe wind gust or two, and even a brief tornado, will be possible, through late afternoon/early evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Sun Apr 07 2024 Valid 072000Z - 081200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE MID-MISSISSIPPI VALLEY... ...SUMMARY... Widely scattered strong/isolated severe thunderstorms remain possible late this afternoon and evening in the lower/mid Mississippi Valley. ...20Z Update... The only change made in the 20Z Day 1 Outlook update was to expand 2 percent tornado probabilities westward into far southeast SD, where adequate insolation has boosted 0-3 km CAPE to 50-100 J/kg ahead of a vertical-vorticity rich surface boundary (per 19Z mesoanalysis). Otherwise, the previous forecast remains on track, with no major changes or additions made. Please see the previous forecast below for more details. ..Squitieri.. 04/07/2024 .PREV DISCUSSION... /ISSUED 1129 AM CDT Sun Apr 07 2024/ ...Mid/lower Mississippi Valley area... While dewpoints remain in the 30s and 40s across the SLGT risk area late this morning, low-level moisture advection is ongoing ahead of the advancing cold front, with low to mid 60s dewpoints now observed across central and southern portions of Arkansas. As the front advances eastward, and the more favorable low-level theta-e airmass continues advecting northward, filtered heating will support modest destabilization, with afternoon mixed-layer CAPE values rising into the 500 to 1000 J/kg range. Stronger ascent will remain just north of the SLGT risk area, as a lobe of vorticity rotating through cyclonic southwesterly flow aloft on the southeastern side of closed upper low over Nebraska crosses Illinois/Indiana this afternoon. Still, scattered convective development is expected to begin by mid to late afternoon across the Mid Mississippi Valley, and southward into the Delta region, in focused low-level ascent near the cold front. While modest CAPE will likely limit severe potential, the deep-layer wind field (veering and increasing favorably with height across the pre-frontal warm sector) will likely augment a few of the stronger updrafts, suggesting that a few storms will become capable of producing hail and/or damaging winds. A tornado or two will also be possible, with hodographs indicating favorable helicity with any right-moving supercell. Severe potential should peak through late afternoon, and then gradually diminish this evening as the boundary layer cools, and the cold front weakens with time. ...Parts of central/southeastern Iowa and vicinity... As the weakening/vertically stacked low shifts northeastward out of Nebraska and across northwestern Iowa this afternoon, continued daytime heating of a marginally moist (40s dewpoints) boundary layer, residing beneath rather steep mid-level lapse rates will continue to facilitate weak destabilization. Thunderstorms have developed late this morning across portions of northern and central Illinois, and across north-central Iowa and into adjacent southern Minnesota. By mid afternoon, new convective development is expected along the occluded front currently moving northeastward across the Nebraska/Iowa border/Mid-Missouri Valley at this time, as it shifts into central and southeastern Iowa. While the evolving, low-topped storms should remain largely sub-severe, a strong to severe wind gust or two, and even a brief tornado, will be possible, through late afternoon/early evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Sun Apr 07 2024 Valid 072000Z - 081200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE MID-MISSISSIPPI VALLEY... ...SUMMARY... Widely scattered strong/isolated severe thunderstorms remain possible late this afternoon and evening in the lower/mid Mississippi Valley. ...20Z Update... The only change made in the 20Z Day 1 Outlook update was to expand 2 percent tornado probabilities westward into far southeast SD, where adequate insolation has boosted 0-3 km CAPE to 50-100 J/kg ahead of a vertical-vorticity rich surface boundary (per 19Z mesoanalysis). Otherwise, the previous forecast remains on track, with no major changes or additions made. Please see the previous forecast below for more details. ..Squitieri.. 04/07/2024 .PREV DISCUSSION... /ISSUED 1129 AM CDT Sun Apr 07 2024/ ...Mid/lower Mississippi Valley area... While dewpoints remain in the 30s and 40s across the SLGT risk area late this morning, low-level moisture advection is ongoing ahead of the advancing cold front, with low to mid 60s dewpoints now observed across central and southern portions of Arkansas. As the front advances eastward, and the more favorable low-level theta-e airmass continues advecting northward, filtered heating will support modest destabilization, with afternoon mixed-layer CAPE values rising into the 500 to 1000 J/kg range. Stronger ascent will remain just north of the SLGT risk area, as a lobe of vorticity rotating through cyclonic southwesterly flow aloft on the southeastern side of closed upper low over Nebraska crosses Illinois/Indiana this afternoon. Still, scattered convective development is expected to begin by mid to late afternoon across the Mid Mississippi Valley, and southward into the Delta region, in focused low-level ascent near the cold front. While modest CAPE will likely limit severe potential, the deep-layer wind field (veering and increasing favorably with height across the pre-frontal warm sector) will likely augment a few of the stronger updrafts, suggesting that a few storms will become capable of producing hail and/or damaging winds. A tornado or two will also be possible, with hodographs indicating favorable helicity with any right-moving supercell. Severe potential should peak through late afternoon, and then gradually diminish this evening as the boundary layer cools, and the cold front weakens with time. ...Parts of central/southeastern Iowa and vicinity... As the weakening/vertically stacked low shifts northeastward out of Nebraska and across northwestern Iowa this afternoon, continued daytime heating of a marginally moist (40s dewpoints) boundary layer, residing beneath rather steep mid-level lapse rates will continue to facilitate weak destabilization. Thunderstorms have developed late this morning across portions of northern and central Illinois, and across north-central Iowa and into adjacent southern Minnesota. By mid afternoon, new convective development is expected along the occluded front currently moving northeastward across the Nebraska/Iowa border/Mid-Missouri Valley at this time, as it shifts into central and southeastern Iowa. While the evolving, low-topped storms should remain largely sub-severe, a strong to severe wind gust or two, and even a brief tornado, will be possible, through late afternoon/early evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Sun Apr 07 2024 Valid 072000Z - 081200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE MID-MISSISSIPPI VALLEY... ...SUMMARY... Widely scattered strong/isolated severe thunderstorms remain possible late this afternoon and evening in the lower/mid Mississippi Valley. ...20Z Update... The only change made in the 20Z Day 1 Outlook update was to expand 2 percent tornado probabilities westward into far southeast SD, where adequate insolation has boosted 0-3 km CAPE to 50-100 J/kg ahead of a vertical-vorticity rich surface boundary (per 19Z mesoanalysis). Otherwise, the previous forecast remains on track, with no major changes or additions made. Please see the previous forecast below for more details. ..Squitieri.. 04/07/2024 .PREV DISCUSSION... /ISSUED 1129 AM CDT Sun Apr 07 2024/ ...Mid/lower Mississippi Valley area... While dewpoints remain in the 30s and 40s across the SLGT risk area late this morning, low-level moisture advection is ongoing ahead of the advancing cold front, with low to mid 60s dewpoints now observed across central and southern portions of Arkansas. As the front advances eastward, and the more favorable low-level theta-e airmass continues advecting northward, filtered heating will support modest destabilization, with afternoon mixed-layer CAPE values rising into the 500 to 1000 J/kg range. Stronger ascent will remain just north of the SLGT risk area, as a lobe of vorticity rotating through cyclonic southwesterly flow aloft on the southeastern side of closed upper low over Nebraska crosses Illinois/Indiana this afternoon. Still, scattered convective development is expected to begin by mid to late afternoon across the Mid Mississippi Valley, and southward into the Delta region, in focused low-level ascent near the cold front. While modest CAPE will likely limit severe potential, the deep-layer wind field (veering and increasing favorably with height across the pre-frontal warm sector) will likely augment a few of the stronger updrafts, suggesting that a few storms will become capable of producing hail and/or damaging winds. A tornado or two will also be possible, with hodographs indicating favorable helicity with any right-moving supercell. Severe potential should peak through late afternoon, and then gradually diminish this evening as the boundary layer cools, and the cold front weakens with time. ...Parts of central/southeastern Iowa and vicinity... As the weakening/vertically stacked low shifts northeastward out of Nebraska and across northwestern Iowa this afternoon, continued daytime heating of a marginally moist (40s dewpoints) boundary layer, residing beneath rather steep mid-level lapse rates will continue to facilitate weak destabilization. Thunderstorms have developed late this morning across portions of northern and central Illinois, and across north-central Iowa and into adjacent southern Minnesota. By mid afternoon, new convective development is expected along the occluded front currently moving northeastward across the Nebraska/Iowa border/Mid-Missouri Valley at this time, as it shifts into central and southeastern Iowa. While the evolving, low-topped storms should remain largely sub-severe, a strong to severe wind gust or two, and even a brief tornado, will be possible, through late afternoon/early evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Sun Apr 07 2024 Valid 072000Z - 081200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE MID-MISSISSIPPI VALLEY... ...SUMMARY... Widely scattered strong/isolated severe thunderstorms remain possible late this afternoon and evening in the lower/mid Mississippi Valley. ...20Z Update... The only change made in the 20Z Day 1 Outlook update was to expand 2 percent tornado probabilities westward into far southeast SD, where adequate insolation has boosted 0-3 km CAPE to 50-100 J/kg ahead of a vertical-vorticity rich surface boundary (per 19Z mesoanalysis). Otherwise, the previous forecast remains on track, with no major changes or additions made. Please see the previous forecast below for more details. ..Squitieri.. 04/07/2024 .PREV DISCUSSION... /ISSUED 1129 AM CDT Sun Apr 07 2024/ ...Mid/lower Mississippi Valley area... While dewpoints remain in the 30s and 40s across the SLGT risk area late this morning, low-level moisture advection is ongoing ahead of the advancing cold front, with low to mid 60s dewpoints now observed across central and southern portions of Arkansas. As the front advances eastward, and the more favorable low-level theta-e airmass continues advecting northward, filtered heating will support modest destabilization, with afternoon mixed-layer CAPE values rising into the 500 to 1000 J/kg range. Stronger ascent will remain just north of the SLGT risk area, as a lobe of vorticity rotating through cyclonic southwesterly flow aloft on the southeastern side of closed upper low over Nebraska crosses Illinois/Indiana this afternoon. Still, scattered convective development is expected to begin by mid to late afternoon across the Mid Mississippi Valley, and southward into the Delta region, in focused low-level ascent near the cold front. While modest CAPE will likely limit severe potential, the deep-layer wind field (veering and increasing favorably with height across the pre-frontal warm sector) will likely augment a few of the stronger updrafts, suggesting that a few storms will become capable of producing hail and/or damaging winds. A tornado or two will also be possible, with hodographs indicating favorable helicity with any right-moving supercell. Severe potential should peak through late afternoon, and then gradually diminish this evening as the boundary layer cools, and the cold front weakens with time. ...Parts of central/southeastern Iowa and vicinity... As the weakening/vertically stacked low shifts northeastward out of Nebraska and across northwestern Iowa this afternoon, continued daytime heating of a marginally moist (40s dewpoints) boundary layer, residing beneath rather steep mid-level lapse rates will continue to facilitate weak destabilization. Thunderstorms have developed late this morning across portions of northern and central Illinois, and across north-central Iowa and into adjacent southern Minnesota. By mid afternoon, new convective development is expected along the occluded front currently moving northeastward across the Nebraska/Iowa border/Mid-Missouri Valley at this time, as it shifts into central and southeastern Iowa. While the evolving, low-topped storms should remain largely sub-severe, a strong to severe wind gust or two, and even a brief tornado, will be possible, through late afternoon/early evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Sun Apr 07 2024 Valid 072000Z - 081200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE MID-MISSISSIPPI VALLEY... ...SUMMARY... Widely scattered strong/isolated severe thunderstorms remain possible late this afternoon and evening in the lower/mid Mississippi Valley. ...20Z Update... The only change made in the 20Z Day 1 Outlook update was to expand 2 percent tornado probabilities westward into far southeast SD, where adequate insolation has boosted 0-3 km CAPE to 50-100 J/kg ahead of a vertical-vorticity rich surface boundary (per 19Z mesoanalysis). Otherwise, the previous forecast remains on track, with no major changes or additions made. Please see the previous forecast below for more details. ..Squitieri.. 04/07/2024 .PREV DISCUSSION... /ISSUED 1129 AM CDT Sun Apr 07 2024/ ...Mid/lower Mississippi Valley area... While dewpoints remain in the 30s and 40s across the SLGT risk area late this morning, low-level moisture advection is ongoing ahead of the advancing cold front, with low to mid 60s dewpoints now observed across central and southern portions of Arkansas. As the front advances eastward, and the more favorable low-level theta-e airmass continues advecting northward, filtered heating will support modest destabilization, with afternoon mixed-layer CAPE values rising into the 500 to 1000 J/kg range. Stronger ascent will remain just north of the SLGT risk area, as a lobe of vorticity rotating through cyclonic southwesterly flow aloft on the southeastern side of closed upper low over Nebraska crosses Illinois/Indiana this afternoon. Still, scattered convective development is expected to begin by mid to late afternoon across the Mid Mississippi Valley, and southward into the Delta region, in focused low-level ascent near the cold front. While modest CAPE will likely limit severe potential, the deep-layer wind field (veering and increasing favorably with height across the pre-frontal warm sector) will likely augment a few of the stronger updrafts, suggesting that a few storms will become capable of producing hail and/or damaging winds. A tornado or two will also be possible, with hodographs indicating favorable helicity with any right-moving supercell. Severe potential should peak through late afternoon, and then gradually diminish this evening as the boundary layer cools, and the cold front weakens with time. ...Parts of central/southeastern Iowa and vicinity... As the weakening/vertically stacked low shifts northeastward out of Nebraska and across northwestern Iowa this afternoon, continued daytime heating of a marginally moist (40s dewpoints) boundary layer, residing beneath rather steep mid-level lapse rates will continue to facilitate weak destabilization. Thunderstorms have developed late this morning across portions of northern and central Illinois, and across north-central Iowa and into adjacent southern Minnesota. By mid afternoon, new convective development is expected along the occluded front currently moving northeastward across the Nebraska/Iowa border/Mid-Missouri Valley at this time, as it shifts into central and southeastern Iowa. While the evolving, low-topped storms should remain largely sub-severe, a strong to severe wind gust or two, and even a brief tornado, will be possible, through late afternoon/early evening. Read more

MD 0380 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF FAR SOUTHEASTERN SD INTO IA...NORTHWESTERN IL...AND EXTREME NORTHEASTERN MO
Mesoscale Discussion 0380 NWS Storm Prediction Center Norman OK 0205 PM CDT Sun Apr 07 2024 Areas affected...Portions of far southeastern SD into IA... northwestern IL...and extreme northeastern MO Concerning...Severe potential...Watch unlikely Valid 071905Z - 072130Z Probability of Watch Issuance...5 percent SUMMARY...An isolated threat for strong/gusty winds and perhaps a brief tornado may exist with any low-topped thunderstorms that can develop. Watch issuance is not expected. DISCUSSION...Recent visible satellite imagery shows a cu field gradually deepening across IA and vicinity along an occluded front extending eastward from a deep surface low in northeastern NE. Low-topped convection has recently developed in far southeastern SD, in close proximity to the surface low. Boundary-layer moisture remains modest across this region, with surface dewpoints generally in the mid 40s to around 50. Still, filtered diurnal heating of this airmass is contributing to around 75-125 J/kg of 0-3 km MLCAPE in a narrow zone focused along the front per latest mesoanalysis estimates. Near-surface vorticity is also likely maximized along this boundary, with modest low-level shear present based on recent VWPs from KDMX/KDVN. Even with the moisture/instability limitations, there should be some chance for ongoing low-topped thunderstorms to gradually increase in coverage and intensity over the next few hours this afternoon into IA and perhaps northwestern IL. Given steepened lapse rates through the cloud-bearing layer, isolated strong/gusty winds appear possible with the more robust cores. A brief tornado/landspout or two may also occur, mainly focused along the occluded front where near-surface vorticity overlaps with maximized 0-3 km CAPE and steep boundary-layer lapse rates. However, the overall severe threat this afternoon is expected to remain too isolated/marginal to justify watch issuance. ..Gleason/Goss.. 04/07/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DVN...DMX...FSD... LAT...LON 41259366 41669477 42599600 43429738 43439631 42619311 42269227 41289055 40359085 40309160 40899231 41259366 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Sun Apr 07 2024 Valid 081200Z - 091200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHEAST NEW MEXICO INTO WEST TEXAS... No changes are needed to the D2 Fire Weather Outlook. See previous discussion below for more information. ..Thornton.. 04/07/2024 .PREV DISCUSSION... /ISSUED 0121 AM CDT Sun Apr 07 2024/ ...Synopsis... On Monday, a mid-level trough will amplify across the Southwest into northern Mexico. Moderate mid-level flow ahead of this trough will overspread the southern High Plains. Given the environment in this region will be deeply mixed, some of this stronger mid-level flow should reach the surface with 20+ mph sustained surface winds expected amid single digit relative humidity. Critically dry fuels in this region will support a large fire threat given the meteorological conditions. ...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 0254 PM CDT Sun Apr 07 2024 Valid 081200Z - 091200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHEAST NEW MEXICO INTO WEST TEXAS... No changes are needed to the D2 Fire Weather Outlook. See previous discussion below for more information. ..Thornton.. 04/07/2024 .PREV DISCUSSION... /ISSUED 0121 AM CDT Sun Apr 07 2024/ ...Synopsis... On Monday, a mid-level trough will amplify across the Southwest into northern Mexico. Moderate mid-level flow ahead of this trough will overspread the southern High Plains. Given the environment in this region will be deeply mixed, some of this stronger mid-level flow should reach the surface with 20+ mph sustained surface winds expected amid single digit relative humidity. Critically dry fuels in this region will support a large fire threat given the meteorological conditions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more