Aggregator

Issued at 2100 UTC THU JUL 04 2024 000 FOPZ11 KNHC 042031 PWSEP1 TROPICAL STORM ALETTA WIND SPEED PROBABILITIES NUMBER 2 NWS NATIONAL HURRICANE CENTER MIAMI FL EP012024 2100 UTC THU JUL 04 2024 AT 2100Z THE CENTER OF TROPICAL STORM ALETTA WAS LOCATED NEAR LATITUDE 17.9 NORTH...LONGITUDE 107.0 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 35 KTS...40 MPH...65 KM/H. Z INDICATES COORDINATED UNIVERSAL TIME (GREENWICH) PACIFIC DAYLIGHT TIME (PDT)...SUBTRACT 7 HOURS FROM Z TIME HAWAIIAN STANDARD TIME (HST)...SUBTRACT 10 HOURS FROM Z TIME WIND SPEED PROBABILITY TABLE FOR SPECIFIC LOCATIONS CHANCES OF SUSTAINED (1-MINUTE AVERAGE) WIND SPEEDS OF AT LEAST ...34 KT (39 MPH... 63 KM/H)... ...50 KT (58 MPH... 93 KM/H)... ...64 KT (74 MPH...119 KM/H)... FOR LOCATIONS AND TIME PERIODS DURING THE NEXT 5 DAYS PROBABILITIES FOR LOCATIONS ARE GIVEN AS OP(CP) WHERE OP IS THE PROBABILITY OF THE EVENT BEGINNING DURING AN INDIVIDUAL TIME PERIOD (ONSET PROBABILITY) (CP) IS THE PROBABILITY OF THE EVENT OCCURRING BETWEEN 18Z THU AND THE FORECAST HOUR (CUMULATIVE PROBABILITY) PROBABILITIES ARE GIVEN IN PERCENT X INDICATES PROBABILITIES LESS THAN 1 PERCENT PROBABILITIES FOR 34 KT AND 50 KT ARE SHOWN AT A GIVEN LOCATION WHEN THE 5-DAY CUMULATIVE PROBABILITY IS AT LEAST 3 PERCENT. PROBABILITIES FOR 34...50...64 KT SHOWN WHEN THE 5-DAY 64-KT CUMULATIVE PROBABILITY IS AT LEAST 1 PERCENT. - - - - WIND SPEED PROBABILITIES FOR SELECTED LOCATIONS - - - - FROM FROM FROM FROM FROM FROM FROM TIME 18Z THU 06Z FRI 18Z FRI 06Z SAT 18Z SAT 18Z SUN 18Z MON PERIODS TO TO TO TO TO TO TO 06Z FRI 18Z FRI 06Z SAT 18Z SAT 18Z SUN 18Z MON 18Z TUE FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT 20N 110W 34 X 3( 3) X( 3) X( 3) X( 3) X( 3) X( 3) ISLA SOCORRO 34 X 4( 4) 5( 9) X( 9) X( 9) X( 9) X( 9) $$ FORECASTER REINHART

Issued at 2100 UTC THU JUL 04 2024 000 WTPZ21 KNHC 042030 TCMEP1 TROPICAL STORM ALETTA FORECAST/ADVISORY NUMBER 2 NWS NATIONAL HURRICANE CENTER MIAMI FL EP012024 2100 UTC THU JUL 04 2024 TROPICAL STORM CENTER LOCATED NEAR 17.9N 107.0W AT 04/2100Z POSITION ACCURATE WITHIN 45 NM PRESENT MOVEMENT TOWARD THE NORTHWEST OR 315 DEGREES AT 9 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1005 MB MAX SUSTAINED WINDS 35 KT WITH GUSTS TO 45 KT. 34 KT....... 40NE 0SE 0SW 40NW. WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT. REPEAT...CENTER LOCATED NEAR 17.9N 107.0W AT 04/2100Z AT 04/1800Z CENTER WAS LOCATED NEAR 17.6N 106.5W FORECAST VALID 05/0600Z 18.3N 108.1W MAX WIND 30 KT...GUSTS 40 KT. FORECAST VALID 05/1800Z 18.2N 109.6W MAX WIND 30 KT...GUSTS 40 KT. FORECAST VALID 06/0600Z 17.8N 111.1W...POST-TROP/REMNT LOW MAX WIND 25 KT...GUSTS 35 KT. FORECAST VALID 06/1800Z 17.3N 112.8W...POST-TROP/REMNT LOW MAX WIND 20 KT...GUSTS 30 KT. FORECAST VALID 07/0600Z...DISSIPATED REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 17.9N 107.0W NEXT ADVISORY AT 05/0300Z $$ FORECASTER REINHART

WW 0505 Status Updates
STATUS REPORT ON WW 505 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 E OWB TO 35 SE SDF TO 10 NE LEX TO 45 NE LEX TO 15 NW HTS. ..MOORE..07/04/24 ATTN...WFO...LMK...JKL...ILN... STATUS REPORT FOR WS 505 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS KYC011-017-021-025-043-049-063-065-067-079-085-093-109-113-123- 129-151-153-155-165-167-173-175-181-189-197-205-229-237- 042140- KY . KENTUCKY COUNTIES INCLUDED ARE BATH BOURBON BOYLE BREATHITT CARTER CLARK ELLIOTT ESTILL FAYETTE GARRARD GRAYSON HARDIN JACKSON JESSAMINE LARUE LEE MADISON MAGOFFIN MARION MENIFEE MERCER MONTGOMERY MORGAN NICHOLAS OWSLEY POWELL ROWAN WASHINGTON WOLFE THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

MD 1534 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR CENTRAL/NORTHERN IOWA...SOUTHERN MINNESOTA
Mesoscale Discussion 1534 NWS Storm Prediction Center Norman OK 0158 PM CDT Thu Jul 04 2024 Areas affected...central/northern Iowa...southern Minnesota Concerning...Severe potential...Watch possible Valid 041858Z - 042100Z Probability of Watch Issuance...40 percent SUMMARY...Thunderstorm activity may increase in coverage through the afternoon and evening with potential for damaging winds and large hail. DISCUSSION...Thunderstorm activity has been ongoing near a cold front moving eastward across Iowa and southern Minnesota. Surface observations show a boundary lifting slowly across northern Iowa, with additional cu developing and a few thunderstorms that have initiated across eastern/northern Iowa into southern Minnesota. Instability has been slow to increase and confined within a smaller corridor across northwestern Iowa. Clearing south of the warm front has led to an increase in heating and some airmass recovery, with MLCAPE up to 1500 J/kg. Additional thunderstorm development will be possible across the cold front and northward lifting boundary through the afternoon. North of the warm front, supercells capable of large hail will be possible, given deep layer shear around 30-45 kts near the IA/MN border. As stronger mid-level flow overspreads central Iowa through the afternoon, deep layer shear will increase across central/northern Iowa. This may support development of a few supercells, with potential for large hail and damaging wind should the thermodynamic environment be able to further destabilize. Given lower confidence in this scenario at this time, trends will be monitored for potential watch issuance later this afternoon. ..Thornton/Gleason.. 07/04/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DVN...ARX...MPX...DMX... LAT...LON 43179483 43769477 44419391 44409205 44039157 43729132 43279117 42839120 42289224 42549476 43179483 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Thu Jul 04 2024 Valid 042000Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE UPPER MISSISSIPPI VALLEY...AND FROM THE SOUTHERN PLAINS TO THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms will be possible through this evening across parts of the upper Mississippi Valley, and from the southern Plains to the lower Ohio Valley. ...20z Update... Severe probabilities have been trimmed across parts of MN/IA in-line with the current location of the surface cold front. Otherwise, only minor changes have been made to the 10 percent general thunderstorm line. Overall forecast thinking remains similar to the previous outlook. However, coverage of severe storms across parts of southern IL into the Ohio Valley (outside of WW 505) is uncertain the remainder of the period. However, a very moist and unstable airmass resides across the area. Additional storms may develop this evening/overnight along the surface front, and any other storms that can develop through evening would pose severe gust potential, precluding a downgrade in probabilities at this time. For information on short term severe potential across the Upper MS Valley and the southern Plains, reference MCDS 1534 and 1535. ..Leitman.. 07/04/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Thu Jul 04 2024/ ...Synopsis... An upper trough over the northern/central Plains will move generally eastward today across the Upper Midwest and mid MS Valley. A separate, convectively augmented mid-level vorticity maximum is present over southern IA/northern MO late this morning. This MCV and associated convection across the OH Valley will move east-northeastward across the OH Valley/Midwest through this evening. At the surface, a weak low should develop eastward across parts of the Upper Midwest in tandem with the large-scale upper trough. Another weak surface low should also track northeastward over the OH Valley with the remnant MCV. A convectively reinforced front draped from the southern Plains northeastward into the mid MS and OH Valleys will likely serve as a focus for strong to severe thunderstorms this afternoon and evening. ...Mid Mississippi Valley into the Ohio Valley and Mid-Atlantic... Mostly elevated thunderstorms are ongoing late this morning across the lower OH Valley. The rather moist low-level airmass along/south of a front will continue to gradually destabilize through the afternoon. Although mid-level lapse rates will remain poor, moderate instability has already developed downstream of activity moving across southern IN and western KY. Additional intensification of this convection will probably occur through early afternoon across parts of central/eastern KY and perhaps southern OH ahead of the MCV. Even though stronger mid-level flow may tend to remain displaced to the north of the front, modest but sufficient deep-layer shear should be present to support multicell clustering. Scattered damaging winds occasionally reaching severe thresholds should be the main threat with this activity as it spreads eastward across the lower OH Valley this afternoon and evening. Low-level flow is forecast to remain generally modest and veered to southwesterly. Still, sufficient speed shear will be present to support some threat for updraft rotation and perhaps a tornado or two, especially if any supercells can develop and persist. Isolated hail may also occur with more robust cores. Confidence in strong convection moving off the Blue Ridge Mountains in the Mid-Atlantic is relatively low. But, any thunderstorms that do form across this region could produce locally damaging winds. ...Southern Plains to the Ozarks... The portion of the cold front extending across the southern Plains into the Ozarks is forecast to make only slow southward progress through this evening. Even with some mid/high-level clouds persisting across these areas, robust daytime heating along/south of the front will likely encourage surface temperatures to warm into the 90s and low 100s. Even though low/mid-level flow will remain fairly weak, rather large surface temperature/dewpoint spreads (up to 30-40 degrees F) and steepened low-level lapse rates should foster a threat for mainly severe/damaging winds with any thunderstorms that can develop this afternoon and evening. Robust convection appears probable along/near the front by 22-00Z, and there appears to be some potential for an organized cluster to develop over the Ozarks/southern MO vicinity and sweep east-southeastward through the late evening. ...Upper Mississippi Valley... A focused area of ascent associated with the upper trough will overspread southern MN and northern IA today. While cloud cover remains prevalent over much of this region late this morning, there has been some recent clearing on the western edge of the cloud deck. A relatively small area of modest destabilization is still anticipated, with MLCAPE around 1000-1500 J/kg possible. A 45-60 kt mid-level jet attendant to the upper trough will overspread the developing warm sector through the afternoon. This jet will aid sufficiently strong deep-layer shear to support supercells with an associated threat for severe hail. Some clustering/upscale growth may eventually occur, which would support a greater threat for severe/damaging winds. This activity should weaken by late evening into WI and northern IL as it encounters a less unstable airmass. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Thu Jul 04 2024 Valid 042000Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE UPPER MISSISSIPPI VALLEY...AND FROM THE SOUTHERN PLAINS TO THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms will be possible through this evening across parts of the upper Mississippi Valley, and from the southern Plains to the lower Ohio Valley. ...20z Update... Severe probabilities have been trimmed across parts of MN/IA in-line with the current location of the surface cold front. Otherwise, only minor changes have been made to the 10 percent general thunderstorm line. Overall forecast thinking remains similar to the previous outlook. However, coverage of severe storms across parts of southern IL into the Ohio Valley (outside of WW 505) is uncertain the remainder of the period. However, a very moist and unstable airmass resides across the area. Additional storms may develop this evening/overnight along the surface front, and any other storms that can develop through evening would pose severe gust potential, precluding a downgrade in probabilities at this time. For information on short term severe potential across the Upper MS Valley and the southern Plains, reference MCDS 1534 and 1535. ..Leitman.. 07/04/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Thu Jul 04 2024/ ...Synopsis... An upper trough over the northern/central Plains will move generally eastward today across the Upper Midwest and mid MS Valley. A separate, convectively augmented mid-level vorticity maximum is present over southern IA/northern MO late this morning. This MCV and associated convection across the OH Valley will move east-northeastward across the OH Valley/Midwest through this evening. At the surface, a weak low should develop eastward across parts of the Upper Midwest in tandem with the large-scale upper trough. Another weak surface low should also track northeastward over the OH Valley with the remnant MCV. A convectively reinforced front draped from the southern Plains northeastward into the mid MS and OH Valleys will likely serve as a focus for strong to severe thunderstorms this afternoon and evening. ...Mid Mississippi Valley into the Ohio Valley and Mid-Atlantic... Mostly elevated thunderstorms are ongoing late this morning across the lower OH Valley. The rather moist low-level airmass along/south of a front will continue to gradually destabilize through the afternoon. Although mid-level lapse rates will remain poor, moderate instability has already developed downstream of activity moving across southern IN and western KY. Additional intensification of this convection will probably occur through early afternoon across parts of central/eastern KY and perhaps southern OH ahead of the MCV. Even though stronger mid-level flow may tend to remain displaced to the north of the front, modest but sufficient deep-layer shear should be present to support multicell clustering. Scattered damaging winds occasionally reaching severe thresholds should be the main threat with this activity as it spreads eastward across the lower OH Valley this afternoon and evening. Low-level flow is forecast to remain generally modest and veered to southwesterly. Still, sufficient speed shear will be present to support some threat for updraft rotation and perhaps a tornado or two, especially if any supercells can develop and persist. Isolated hail may also occur with more robust cores. Confidence in strong convection moving off the Blue Ridge Mountains in the Mid-Atlantic is relatively low. But, any thunderstorms that do form across this region could produce locally damaging winds. ...Southern Plains to the Ozarks... The portion of the cold front extending across the southern Plains into the Ozarks is forecast to make only slow southward progress through this evening. Even with some mid/high-level clouds persisting across these areas, robust daytime heating along/south of the front will likely encourage surface temperatures to warm into the 90s and low 100s. Even though low/mid-level flow will remain fairly weak, rather large surface temperature/dewpoint spreads (up to 30-40 degrees F) and steepened low-level lapse rates should foster a threat for mainly severe/damaging winds with any thunderstorms that can develop this afternoon and evening. Robust convection appears probable along/near the front by 22-00Z, and there appears to be some potential for an organized cluster to develop over the Ozarks/southern MO vicinity and sweep east-southeastward through the late evening. ...Upper Mississippi Valley... A focused area of ascent associated with the upper trough will overspread southern MN and northern IA today. While cloud cover remains prevalent over much of this region late this morning, there has been some recent clearing on the western edge of the cloud deck. A relatively small area of modest destabilization is still anticipated, with MLCAPE around 1000-1500 J/kg possible. A 45-60 kt mid-level jet attendant to the upper trough will overspread the developing warm sector through the afternoon. This jet will aid sufficiently strong deep-layer shear to support supercells with an associated threat for severe hail. Some clustering/upscale growth may eventually occur, which would support a greater threat for severe/damaging winds. This activity should weaken by late evening into WI and northern IL as it encounters a less unstable airmass. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Thu Jul 04 2024 Valid 042000Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE UPPER MISSISSIPPI VALLEY...AND FROM THE SOUTHERN PLAINS TO THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms will be possible through this evening across parts of the upper Mississippi Valley, and from the southern Plains to the lower Ohio Valley. ...20z Update... Severe probabilities have been trimmed across parts of MN/IA in-line with the current location of the surface cold front. Otherwise, only minor changes have been made to the 10 percent general thunderstorm line. Overall forecast thinking remains similar to the previous outlook. However, coverage of severe storms across parts of southern IL into the Ohio Valley (outside of WW 505) is uncertain the remainder of the period. However, a very moist and unstable airmass resides across the area. Additional storms may develop this evening/overnight along the surface front, and any other storms that can develop through evening would pose severe gust potential, precluding a downgrade in probabilities at this time. For information on short term severe potential across the Upper MS Valley and the southern Plains, reference MCDS 1534 and 1535. ..Leitman.. 07/04/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Thu Jul 04 2024/ ...Synopsis... An upper trough over the northern/central Plains will move generally eastward today across the Upper Midwest and mid MS Valley. A separate, convectively augmented mid-level vorticity maximum is present over southern IA/northern MO late this morning. This MCV and associated convection across the OH Valley will move east-northeastward across the OH Valley/Midwest through this evening. At the surface, a weak low should develop eastward across parts of the Upper Midwest in tandem with the large-scale upper trough. Another weak surface low should also track northeastward over the OH Valley with the remnant MCV. A convectively reinforced front draped from the southern Plains northeastward into the mid MS and OH Valleys will likely serve as a focus for strong to severe thunderstorms this afternoon and evening. ...Mid Mississippi Valley into the Ohio Valley and Mid-Atlantic... Mostly elevated thunderstorms are ongoing late this morning across the lower OH Valley. The rather moist low-level airmass along/south of a front will continue to gradually destabilize through the afternoon. Although mid-level lapse rates will remain poor, moderate instability has already developed downstream of activity moving across southern IN and western KY. Additional intensification of this convection will probably occur through early afternoon across parts of central/eastern KY and perhaps southern OH ahead of the MCV. Even though stronger mid-level flow may tend to remain displaced to the north of the front, modest but sufficient deep-layer shear should be present to support multicell clustering. Scattered damaging winds occasionally reaching severe thresholds should be the main threat with this activity as it spreads eastward across the lower OH Valley this afternoon and evening. Low-level flow is forecast to remain generally modest and veered to southwesterly. Still, sufficient speed shear will be present to support some threat for updraft rotation and perhaps a tornado or two, especially if any supercells can develop and persist. Isolated hail may also occur with more robust cores. Confidence in strong convection moving off the Blue Ridge Mountains in the Mid-Atlantic is relatively low. But, any thunderstorms that do form across this region could produce locally damaging winds. ...Southern Plains to the Ozarks... The portion of the cold front extending across the southern Plains into the Ozarks is forecast to make only slow southward progress through this evening. Even with some mid/high-level clouds persisting across these areas, robust daytime heating along/south of the front will likely encourage surface temperatures to warm into the 90s and low 100s. Even though low/mid-level flow will remain fairly weak, rather large surface temperature/dewpoint spreads (up to 30-40 degrees F) and steepened low-level lapse rates should foster a threat for mainly severe/damaging winds with any thunderstorms that can develop this afternoon and evening. Robust convection appears probable along/near the front by 22-00Z, and there appears to be some potential for an organized cluster to develop over the Ozarks/southern MO vicinity and sweep east-southeastward through the late evening. ...Upper Mississippi Valley... A focused area of ascent associated with the upper trough will overspread southern MN and northern IA today. While cloud cover remains prevalent over much of this region late this morning, there has been some recent clearing on the western edge of the cloud deck. A relatively small area of modest destabilization is still anticipated, with MLCAPE around 1000-1500 J/kg possible. A 45-60 kt mid-level jet attendant to the upper trough will overspread the developing warm sector through the afternoon. This jet will aid sufficiently strong deep-layer shear to support supercells with an associated threat for severe hail. Some clustering/upscale growth may eventually occur, which would support a greater threat for severe/damaging winds. This activity should weaken by late evening into WI and northern IL as it encounters a less unstable airmass. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Thu Jul 04 2024 Valid 042000Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE UPPER MISSISSIPPI VALLEY...AND FROM THE SOUTHERN PLAINS TO THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms will be possible through this evening across parts of the upper Mississippi Valley, and from the southern Plains to the lower Ohio Valley. ...20z Update... Severe probabilities have been trimmed across parts of MN/IA in-line with the current location of the surface cold front. Otherwise, only minor changes have been made to the 10 percent general thunderstorm line. Overall forecast thinking remains similar to the previous outlook. However, coverage of severe storms across parts of southern IL into the Ohio Valley (outside of WW 505) is uncertain the remainder of the period. However, a very moist and unstable airmass resides across the area. Additional storms may develop this evening/overnight along the surface front, and any other storms that can develop through evening would pose severe gust potential, precluding a downgrade in probabilities at this time. For information on short term severe potential across the Upper MS Valley and the southern Plains, reference MCDS 1534 and 1535. ..Leitman.. 07/04/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Thu Jul 04 2024/ ...Synopsis... An upper trough over the northern/central Plains will move generally eastward today across the Upper Midwest and mid MS Valley. A separate, convectively augmented mid-level vorticity maximum is present over southern IA/northern MO late this morning. This MCV and associated convection across the OH Valley will move east-northeastward across the OH Valley/Midwest through this evening. At the surface, a weak low should develop eastward across parts of the Upper Midwest in tandem with the large-scale upper trough. Another weak surface low should also track northeastward over the OH Valley with the remnant MCV. A convectively reinforced front draped from the southern Plains northeastward into the mid MS and OH Valleys will likely serve as a focus for strong to severe thunderstorms this afternoon and evening. ...Mid Mississippi Valley into the Ohio Valley and Mid-Atlantic... Mostly elevated thunderstorms are ongoing late this morning across the lower OH Valley. The rather moist low-level airmass along/south of a front will continue to gradually destabilize through the afternoon. Although mid-level lapse rates will remain poor, moderate instability has already developed downstream of activity moving across southern IN and western KY. Additional intensification of this convection will probably occur through early afternoon across parts of central/eastern KY and perhaps southern OH ahead of the MCV. Even though stronger mid-level flow may tend to remain displaced to the north of the front, modest but sufficient deep-layer shear should be present to support multicell clustering. Scattered damaging winds occasionally reaching severe thresholds should be the main threat with this activity as it spreads eastward across the lower OH Valley this afternoon and evening. Low-level flow is forecast to remain generally modest and veered to southwesterly. Still, sufficient speed shear will be present to support some threat for updraft rotation and perhaps a tornado or two, especially if any supercells can develop and persist. Isolated hail may also occur with more robust cores. Confidence in strong convection moving off the Blue Ridge Mountains in the Mid-Atlantic is relatively low. But, any thunderstorms that do form across this region could produce locally damaging winds. ...Southern Plains to the Ozarks... The portion of the cold front extending across the southern Plains into the Ozarks is forecast to make only slow southward progress through this evening. Even with some mid/high-level clouds persisting across these areas, robust daytime heating along/south of the front will likely encourage surface temperatures to warm into the 90s and low 100s. Even though low/mid-level flow will remain fairly weak, rather large surface temperature/dewpoint spreads (up to 30-40 degrees F) and steepened low-level lapse rates should foster a threat for mainly severe/damaging winds with any thunderstorms that can develop this afternoon and evening. Robust convection appears probable along/near the front by 22-00Z, and there appears to be some potential for an organized cluster to develop over the Ozarks/southern MO vicinity and sweep east-southeastward through the late evening. ...Upper Mississippi Valley... A focused area of ascent associated with the upper trough will overspread southern MN and northern IA today. While cloud cover remains prevalent over much of this region late this morning, there has been some recent clearing on the western edge of the cloud deck. A relatively small area of modest destabilization is still anticipated, with MLCAPE around 1000-1500 J/kg possible. A 45-60 kt mid-level jet attendant to the upper trough will overspread the developing warm sector through the afternoon. This jet will aid sufficiently strong deep-layer shear to support supercells with an associated threat for severe hail. Some clustering/upscale growth may eventually occur, which would support a greater threat for severe/damaging winds. This activity should weaken by late evening into WI and northern IL as it encounters a less unstable airmass. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Thu Jul 04 2024 Valid 042000Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE UPPER MISSISSIPPI VALLEY...AND FROM THE SOUTHERN PLAINS TO THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms will be possible through this evening across parts of the upper Mississippi Valley, and from the southern Plains to the lower Ohio Valley. ...20z Update... Severe probabilities have been trimmed across parts of MN/IA in-line with the current location of the surface cold front. Otherwise, only minor changes have been made to the 10 percent general thunderstorm line. Overall forecast thinking remains similar to the previous outlook. However, coverage of severe storms across parts of southern IL into the Ohio Valley (outside of WW 505) is uncertain the remainder of the period. However, a very moist and unstable airmass resides across the area. Additional storms may develop this evening/overnight along the surface front, and any other storms that can develop through evening would pose severe gust potential, precluding a downgrade in probabilities at this time. For information on short term severe potential across the Upper MS Valley and the southern Plains, reference MCDS 1534 and 1535. ..Leitman.. 07/04/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Thu Jul 04 2024/ ...Synopsis... An upper trough over the northern/central Plains will move generally eastward today across the Upper Midwest and mid MS Valley. A separate, convectively augmented mid-level vorticity maximum is present over southern IA/northern MO late this morning. This MCV and associated convection across the OH Valley will move east-northeastward across the OH Valley/Midwest through this evening. At the surface, a weak low should develop eastward across parts of the Upper Midwest in tandem with the large-scale upper trough. Another weak surface low should also track northeastward over the OH Valley with the remnant MCV. A convectively reinforced front draped from the southern Plains northeastward into the mid MS and OH Valleys will likely serve as a focus for strong to severe thunderstorms this afternoon and evening. ...Mid Mississippi Valley into the Ohio Valley and Mid-Atlantic... Mostly elevated thunderstorms are ongoing late this morning across the lower OH Valley. The rather moist low-level airmass along/south of a front will continue to gradually destabilize through the afternoon. Although mid-level lapse rates will remain poor, moderate instability has already developed downstream of activity moving across southern IN and western KY. Additional intensification of this convection will probably occur through early afternoon across parts of central/eastern KY and perhaps southern OH ahead of the MCV. Even though stronger mid-level flow may tend to remain displaced to the north of the front, modest but sufficient deep-layer shear should be present to support multicell clustering. Scattered damaging winds occasionally reaching severe thresholds should be the main threat with this activity as it spreads eastward across the lower OH Valley this afternoon and evening. Low-level flow is forecast to remain generally modest and veered to southwesterly. Still, sufficient speed shear will be present to support some threat for updraft rotation and perhaps a tornado or two, especially if any supercells can develop and persist. Isolated hail may also occur with more robust cores. Confidence in strong convection moving off the Blue Ridge Mountains in the Mid-Atlantic is relatively low. But, any thunderstorms that do form across this region could produce locally damaging winds. ...Southern Plains to the Ozarks... The portion of the cold front extending across the southern Plains into the Ozarks is forecast to make only slow southward progress through this evening. Even with some mid/high-level clouds persisting across these areas, robust daytime heating along/south of the front will likely encourage surface temperatures to warm into the 90s and low 100s. Even though low/mid-level flow will remain fairly weak, rather large surface temperature/dewpoint spreads (up to 30-40 degrees F) and steepened low-level lapse rates should foster a threat for mainly severe/damaging winds with any thunderstorms that can develop this afternoon and evening. Robust convection appears probable along/near the front by 22-00Z, and there appears to be some potential for an organized cluster to develop over the Ozarks/southern MO vicinity and sweep east-southeastward through the late evening. ...Upper Mississippi Valley... A focused area of ascent associated with the upper trough will overspread southern MN and northern IA today. While cloud cover remains prevalent over much of this region late this morning, there has been some recent clearing on the western edge of the cloud deck. A relatively small area of modest destabilization is still anticipated, with MLCAPE around 1000-1500 J/kg possible. A 45-60 kt mid-level jet attendant to the upper trough will overspread the developing warm sector through the afternoon. This jet will aid sufficiently strong deep-layer shear to support supercells with an associated threat for severe hail. Some clustering/upscale growth may eventually occur, which would support a greater threat for severe/damaging winds. This activity should weaken by late evening into WI and northern IL as it encounters a less unstable airmass. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Thu Jul 04 2024 Valid 042000Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE UPPER MISSISSIPPI VALLEY...AND FROM THE SOUTHERN PLAINS TO THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms will be possible through this evening across parts of the upper Mississippi Valley, and from the southern Plains to the lower Ohio Valley. ...20z Update... Severe probabilities have been trimmed across parts of MN/IA in-line with the current location of the surface cold front. Otherwise, only minor changes have been made to the 10 percent general thunderstorm line. Overall forecast thinking remains similar to the previous outlook. However, coverage of severe storms across parts of southern IL into the Ohio Valley (outside of WW 505) is uncertain the remainder of the period. However, a very moist and unstable airmass resides across the area. Additional storms may develop this evening/overnight along the surface front, and any other storms that can develop through evening would pose severe gust potential, precluding a downgrade in probabilities at this time. For information on short term severe potential across the Upper MS Valley and the southern Plains, reference MCDS 1534 and 1535. ..Leitman.. 07/04/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Thu Jul 04 2024/ ...Synopsis... An upper trough over the northern/central Plains will move generally eastward today across the Upper Midwest and mid MS Valley. A separate, convectively augmented mid-level vorticity maximum is present over southern IA/northern MO late this morning. This MCV and associated convection across the OH Valley will move east-northeastward across the OH Valley/Midwest through this evening. At the surface, a weak low should develop eastward across parts of the Upper Midwest in tandem with the large-scale upper trough. Another weak surface low should also track northeastward over the OH Valley with the remnant MCV. A convectively reinforced front draped from the southern Plains northeastward into the mid MS and OH Valleys will likely serve as a focus for strong to severe thunderstorms this afternoon and evening. ...Mid Mississippi Valley into the Ohio Valley and Mid-Atlantic... Mostly elevated thunderstorms are ongoing late this morning across the lower OH Valley. The rather moist low-level airmass along/south of a front will continue to gradually destabilize through the afternoon. Although mid-level lapse rates will remain poor, moderate instability has already developed downstream of activity moving across southern IN and western KY. Additional intensification of this convection will probably occur through early afternoon across parts of central/eastern KY and perhaps southern OH ahead of the MCV. Even though stronger mid-level flow may tend to remain displaced to the north of the front, modest but sufficient deep-layer shear should be present to support multicell clustering. Scattered damaging winds occasionally reaching severe thresholds should be the main threat with this activity as it spreads eastward across the lower OH Valley this afternoon and evening. Low-level flow is forecast to remain generally modest and veered to southwesterly. Still, sufficient speed shear will be present to support some threat for updraft rotation and perhaps a tornado or two, especially if any supercells can develop and persist. Isolated hail may also occur with more robust cores. Confidence in strong convection moving off the Blue Ridge Mountains in the Mid-Atlantic is relatively low. But, any thunderstorms that do form across this region could produce locally damaging winds. ...Southern Plains to the Ozarks... The portion of the cold front extending across the southern Plains into the Ozarks is forecast to make only slow southward progress through this evening. Even with some mid/high-level clouds persisting across these areas, robust daytime heating along/south of the front will likely encourage surface temperatures to warm into the 90s and low 100s. Even though low/mid-level flow will remain fairly weak, rather large surface temperature/dewpoint spreads (up to 30-40 degrees F) and steepened low-level lapse rates should foster a threat for mainly severe/damaging winds with any thunderstorms that can develop this afternoon and evening. Robust convection appears probable along/near the front by 22-00Z, and there appears to be some potential for an organized cluster to develop over the Ozarks/southern MO vicinity and sweep east-southeastward through the late evening. ...Upper Mississippi Valley... A focused area of ascent associated with the upper trough will overspread southern MN and northern IA today. While cloud cover remains prevalent over much of this region late this morning, there has been some recent clearing on the western edge of the cloud deck. A relatively small area of modest destabilization is still anticipated, with MLCAPE around 1000-1500 J/kg possible. A 45-60 kt mid-level jet attendant to the upper trough will overspread the developing warm sector through the afternoon. This jet will aid sufficiently strong deep-layer shear to support supercells with an associated threat for severe hail. Some clustering/upscale growth may eventually occur, which would support a greater threat for severe/damaging winds. This activity should weaken by late evening into WI and northern IL as it encounters a less unstable airmass. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Thu Jul 04 2024 Valid 042000Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE UPPER MISSISSIPPI VALLEY...AND FROM THE SOUTHERN PLAINS TO THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms will be possible through this evening across parts of the upper Mississippi Valley, and from the southern Plains to the lower Ohio Valley. ...20z Update... Severe probabilities have been trimmed across parts of MN/IA in-line with the current location of the surface cold front. Otherwise, only minor changes have been made to the 10 percent general thunderstorm line. Overall forecast thinking remains similar to the previous outlook. However, coverage of severe storms across parts of southern IL into the Ohio Valley (outside of WW 505) is uncertain the remainder of the period. However, a very moist and unstable airmass resides across the area. Additional storms may develop this evening/overnight along the surface front, and any other storms that can develop through evening would pose severe gust potential, precluding a downgrade in probabilities at this time. For information on short term severe potential across the Upper MS Valley and the southern Plains, reference MCDS 1534 and 1535. ..Leitman.. 07/04/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Thu Jul 04 2024/ ...Synopsis... An upper trough over the northern/central Plains will move generally eastward today across the Upper Midwest and mid MS Valley. A separate, convectively augmented mid-level vorticity maximum is present over southern IA/northern MO late this morning. This MCV and associated convection across the OH Valley will move east-northeastward across the OH Valley/Midwest through this evening. At the surface, a weak low should develop eastward across parts of the Upper Midwest in tandem with the large-scale upper trough. Another weak surface low should also track northeastward over the OH Valley with the remnant MCV. A convectively reinforced front draped from the southern Plains northeastward into the mid MS and OH Valleys will likely serve as a focus for strong to severe thunderstorms this afternoon and evening. ...Mid Mississippi Valley into the Ohio Valley and Mid-Atlantic... Mostly elevated thunderstorms are ongoing late this morning across the lower OH Valley. The rather moist low-level airmass along/south of a front will continue to gradually destabilize through the afternoon. Although mid-level lapse rates will remain poor, moderate instability has already developed downstream of activity moving across southern IN and western KY. Additional intensification of this convection will probably occur through early afternoon across parts of central/eastern KY and perhaps southern OH ahead of the MCV. Even though stronger mid-level flow may tend to remain displaced to the north of the front, modest but sufficient deep-layer shear should be present to support multicell clustering. Scattered damaging winds occasionally reaching severe thresholds should be the main threat with this activity as it spreads eastward across the lower OH Valley this afternoon and evening. Low-level flow is forecast to remain generally modest and veered to southwesterly. Still, sufficient speed shear will be present to support some threat for updraft rotation and perhaps a tornado or two, especially if any supercells can develop and persist. Isolated hail may also occur with more robust cores. Confidence in strong convection moving off the Blue Ridge Mountains in the Mid-Atlantic is relatively low. But, any thunderstorms that do form across this region could produce locally damaging winds. ...Southern Plains to the Ozarks... The portion of the cold front extending across the southern Plains into the Ozarks is forecast to make only slow southward progress through this evening. Even with some mid/high-level clouds persisting across these areas, robust daytime heating along/south of the front will likely encourage surface temperatures to warm into the 90s and low 100s. Even though low/mid-level flow will remain fairly weak, rather large surface temperature/dewpoint spreads (up to 30-40 degrees F) and steepened low-level lapse rates should foster a threat for mainly severe/damaging winds with any thunderstorms that can develop this afternoon and evening. Robust convection appears probable along/near the front by 22-00Z, and there appears to be some potential for an organized cluster to develop over the Ozarks/southern MO vicinity and sweep east-southeastward through the late evening. ...Upper Mississippi Valley... A focused area of ascent associated with the upper trough will overspread southern MN and northern IA today. While cloud cover remains prevalent over much of this region late this morning, there has been some recent clearing on the western edge of the cloud deck. A relatively small area of modest destabilization is still anticipated, with MLCAPE around 1000-1500 J/kg possible. A 45-60 kt mid-level jet attendant to the upper trough will overspread the developing warm sector through the afternoon. This jet will aid sufficiently strong deep-layer shear to support supercells with an associated threat for severe hail. Some clustering/upscale growth may eventually occur, which would support a greater threat for severe/damaging winds. This activity should weaken by late evening into WI and northern IL as it encounters a less unstable airmass. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Thu Jul 04 2024 Valid 042000Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE UPPER MISSISSIPPI VALLEY...AND FROM THE SOUTHERN PLAINS TO THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms will be possible through this evening across parts of the upper Mississippi Valley, and from the southern Plains to the lower Ohio Valley. ...20z Update... Severe probabilities have been trimmed across parts of MN/IA in-line with the current location of the surface cold front. Otherwise, only minor changes have been made to the 10 percent general thunderstorm line. Overall forecast thinking remains similar to the previous outlook. However, coverage of severe storms across parts of southern IL into the Ohio Valley (outside of WW 505) is uncertain the remainder of the period. However, a very moist and unstable airmass resides across the area. Additional storms may develop this evening/overnight along the surface front, and any other storms that can develop through evening would pose severe gust potential, precluding a downgrade in probabilities at this time. For information on short term severe potential across the Upper MS Valley and the southern Plains, reference MCDS 1534 and 1535. ..Leitman.. 07/04/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Thu Jul 04 2024/ ...Synopsis... An upper trough over the northern/central Plains will move generally eastward today across the Upper Midwest and mid MS Valley. A separate, convectively augmented mid-level vorticity maximum is present over southern IA/northern MO late this morning. This MCV and associated convection across the OH Valley will move east-northeastward across the OH Valley/Midwest through this evening. At the surface, a weak low should develop eastward across parts of the Upper Midwest in tandem with the large-scale upper trough. Another weak surface low should also track northeastward over the OH Valley with the remnant MCV. A convectively reinforced front draped from the southern Plains northeastward into the mid MS and OH Valleys will likely serve as a focus for strong to severe thunderstorms this afternoon and evening. ...Mid Mississippi Valley into the Ohio Valley and Mid-Atlantic... Mostly elevated thunderstorms are ongoing late this morning across the lower OH Valley. The rather moist low-level airmass along/south of a front will continue to gradually destabilize through the afternoon. Although mid-level lapse rates will remain poor, moderate instability has already developed downstream of activity moving across southern IN and western KY. Additional intensification of this convection will probably occur through early afternoon across parts of central/eastern KY and perhaps southern OH ahead of the MCV. Even though stronger mid-level flow may tend to remain displaced to the north of the front, modest but sufficient deep-layer shear should be present to support multicell clustering. Scattered damaging winds occasionally reaching severe thresholds should be the main threat with this activity as it spreads eastward across the lower OH Valley this afternoon and evening. Low-level flow is forecast to remain generally modest and veered to southwesterly. Still, sufficient speed shear will be present to support some threat for updraft rotation and perhaps a tornado or two, especially if any supercells can develop and persist. Isolated hail may also occur with more robust cores. Confidence in strong convection moving off the Blue Ridge Mountains in the Mid-Atlantic is relatively low. But, any thunderstorms that do form across this region could produce locally damaging winds. ...Southern Plains to the Ozarks... The portion of the cold front extending across the southern Plains into the Ozarks is forecast to make only slow southward progress through this evening. Even with some mid/high-level clouds persisting across these areas, robust daytime heating along/south of the front will likely encourage surface temperatures to warm into the 90s and low 100s. Even though low/mid-level flow will remain fairly weak, rather large surface temperature/dewpoint spreads (up to 30-40 degrees F) and steepened low-level lapse rates should foster a threat for mainly severe/damaging winds with any thunderstorms that can develop this afternoon and evening. Robust convection appears probable along/near the front by 22-00Z, and there appears to be some potential for an organized cluster to develop over the Ozarks/southern MO vicinity and sweep east-southeastward through the late evening. ...Upper Mississippi Valley... A focused area of ascent associated with the upper trough will overspread southern MN and northern IA today. While cloud cover remains prevalent over much of this region late this morning, there has been some recent clearing on the western edge of the cloud deck. A relatively small area of modest destabilization is still anticipated, with MLCAPE around 1000-1500 J/kg possible. A 45-60 kt mid-level jet attendant to the upper trough will overspread the developing warm sector through the afternoon. This jet will aid sufficiently strong deep-layer shear to support supercells with an associated threat for severe hail. Some clustering/upscale growth may eventually occur, which would support a greater threat for severe/damaging winds. This activity should weaken by late evening into WI and northern IL as it encounters a less unstable airmass. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Thu Jul 04 2024 Valid 042000Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE UPPER MISSISSIPPI VALLEY...AND FROM THE SOUTHERN PLAINS TO THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms will be possible through this evening across parts of the upper Mississippi Valley, and from the southern Plains to the lower Ohio Valley. ...20z Update... Severe probabilities have been trimmed across parts of MN/IA in-line with the current location of the surface cold front. Otherwise, only minor changes have been made to the 10 percent general thunderstorm line. Overall forecast thinking remains similar to the previous outlook. However, coverage of severe storms across parts of southern IL into the Ohio Valley (outside of WW 505) is uncertain the remainder of the period. However, a very moist and unstable airmass resides across the area. Additional storms may develop this evening/overnight along the surface front, and any other storms that can develop through evening would pose severe gust potential, precluding a downgrade in probabilities at this time. For information on short term severe potential across the Upper MS Valley and the southern Plains, reference MCDS 1534 and 1535. ..Leitman.. 07/04/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Thu Jul 04 2024/ ...Synopsis... An upper trough over the northern/central Plains will move generally eastward today across the Upper Midwest and mid MS Valley. A separate, convectively augmented mid-level vorticity maximum is present over southern IA/northern MO late this morning. This MCV and associated convection across the OH Valley will move east-northeastward across the OH Valley/Midwest through this evening. At the surface, a weak low should develop eastward across parts of the Upper Midwest in tandem with the large-scale upper trough. Another weak surface low should also track northeastward over the OH Valley with the remnant MCV. A convectively reinforced front draped from the southern Plains northeastward into the mid MS and OH Valleys will likely serve as a focus for strong to severe thunderstorms this afternoon and evening. ...Mid Mississippi Valley into the Ohio Valley and Mid-Atlantic... Mostly elevated thunderstorms are ongoing late this morning across the lower OH Valley. The rather moist low-level airmass along/south of a front will continue to gradually destabilize through the afternoon. Although mid-level lapse rates will remain poor, moderate instability has already developed downstream of activity moving across southern IN and western KY. Additional intensification of this convection will probably occur through early afternoon across parts of central/eastern KY and perhaps southern OH ahead of the MCV. Even though stronger mid-level flow may tend to remain displaced to the north of the front, modest but sufficient deep-layer shear should be present to support multicell clustering. Scattered damaging winds occasionally reaching severe thresholds should be the main threat with this activity as it spreads eastward across the lower OH Valley this afternoon and evening. Low-level flow is forecast to remain generally modest and veered to southwesterly. Still, sufficient speed shear will be present to support some threat for updraft rotation and perhaps a tornado or two, especially if any supercells can develop and persist. Isolated hail may also occur with more robust cores. Confidence in strong convection moving off the Blue Ridge Mountains in the Mid-Atlantic is relatively low. But, any thunderstorms that do form across this region could produce locally damaging winds. ...Southern Plains to the Ozarks... The portion of the cold front extending across the southern Plains into the Ozarks is forecast to make only slow southward progress through this evening. Even with some mid/high-level clouds persisting across these areas, robust daytime heating along/south of the front will likely encourage surface temperatures to warm into the 90s and low 100s. Even though low/mid-level flow will remain fairly weak, rather large surface temperature/dewpoint spreads (up to 30-40 degrees F) and steepened low-level lapse rates should foster a threat for mainly severe/damaging winds with any thunderstorms that can develop this afternoon and evening. Robust convection appears probable along/near the front by 22-00Z, and there appears to be some potential for an organized cluster to develop over the Ozarks/southern MO vicinity and sweep east-southeastward through the late evening. ...Upper Mississippi Valley... A focused area of ascent associated with the upper trough will overspread southern MN and northern IA today. While cloud cover remains prevalent over much of this region late this morning, there has been some recent clearing on the western edge of the cloud deck. A relatively small area of modest destabilization is still anticipated, with MLCAPE around 1000-1500 J/kg possible. A 45-60 kt mid-level jet attendant to the upper trough will overspread the developing warm sector through the afternoon. This jet will aid sufficiently strong deep-layer shear to support supercells with an associated threat for severe hail. Some clustering/upscale growth may eventually occur, which would support a greater threat for severe/damaging winds. This activity should weaken by late evening into WI and northern IL as it encounters a less unstable airmass. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Thu Jul 04 2024 Valid 042000Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE UPPER MISSISSIPPI VALLEY...AND FROM THE SOUTHERN PLAINS TO THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms will be possible through this evening across parts of the upper Mississippi Valley, and from the southern Plains to the lower Ohio Valley. ...20z Update... Severe probabilities have been trimmed across parts of MN/IA in-line with the current location of the surface cold front. Otherwise, only minor changes have been made to the 10 percent general thunderstorm line. Overall forecast thinking remains similar to the previous outlook. However, coverage of severe storms across parts of southern IL into the Ohio Valley (outside of WW 505) is uncertain the remainder of the period. However, a very moist and unstable airmass resides across the area. Additional storms may develop this evening/overnight along the surface front, and any other storms that can develop through evening would pose severe gust potential, precluding a downgrade in probabilities at this time. For information on short term severe potential across the Upper MS Valley and the southern Plains, reference MCDS 1534 and 1535. ..Leitman.. 07/04/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Thu Jul 04 2024/ ...Synopsis... An upper trough over the northern/central Plains will move generally eastward today across the Upper Midwest and mid MS Valley. A separate, convectively augmented mid-level vorticity maximum is present over southern IA/northern MO late this morning. This MCV and associated convection across the OH Valley will move east-northeastward across the OH Valley/Midwest through this evening. At the surface, a weak low should develop eastward across parts of the Upper Midwest in tandem with the large-scale upper trough. Another weak surface low should also track northeastward over the OH Valley with the remnant MCV. A convectively reinforced front draped from the southern Plains northeastward into the mid MS and OH Valleys will likely serve as a focus for strong to severe thunderstorms this afternoon and evening. ...Mid Mississippi Valley into the Ohio Valley and Mid-Atlantic... Mostly elevated thunderstorms are ongoing late this morning across the lower OH Valley. The rather moist low-level airmass along/south of a front will continue to gradually destabilize through the afternoon. Although mid-level lapse rates will remain poor, moderate instability has already developed downstream of activity moving across southern IN and western KY. Additional intensification of this convection will probably occur through early afternoon across parts of central/eastern KY and perhaps southern OH ahead of the MCV. Even though stronger mid-level flow may tend to remain displaced to the north of the front, modest but sufficient deep-layer shear should be present to support multicell clustering. Scattered damaging winds occasionally reaching severe thresholds should be the main threat with this activity as it spreads eastward across the lower OH Valley this afternoon and evening. Low-level flow is forecast to remain generally modest and veered to southwesterly. Still, sufficient speed shear will be present to support some threat for updraft rotation and perhaps a tornado or two, especially if any supercells can develop and persist. Isolated hail may also occur with more robust cores. Confidence in strong convection moving off the Blue Ridge Mountains in the Mid-Atlantic is relatively low. But, any thunderstorms that do form across this region could produce locally damaging winds. ...Southern Plains to the Ozarks... The portion of the cold front extending across the southern Plains into the Ozarks is forecast to make only slow southward progress through this evening. Even with some mid/high-level clouds persisting across these areas, robust daytime heating along/south of the front will likely encourage surface temperatures to warm into the 90s and low 100s. Even though low/mid-level flow will remain fairly weak, rather large surface temperature/dewpoint spreads (up to 30-40 degrees F) and steepened low-level lapse rates should foster a threat for mainly severe/damaging winds with any thunderstorms that can develop this afternoon and evening. Robust convection appears probable along/near the front by 22-00Z, and there appears to be some potential for an organized cluster to develop over the Ozarks/southern MO vicinity and sweep east-southeastward through the late evening. ...Upper Mississippi Valley... A focused area of ascent associated with the upper trough will overspread southern MN and northern IA today. While cloud cover remains prevalent over much of this region late this morning, there has been some recent clearing on the western edge of the cloud deck. A relatively small area of modest destabilization is still anticipated, with MLCAPE around 1000-1500 J/kg possible. A 45-60 kt mid-level jet attendant to the upper trough will overspread the developing warm sector through the afternoon. This jet will aid sufficiently strong deep-layer shear to support supercells with an associated threat for severe hail. Some clustering/upscale growth may eventually occur, which would support a greater threat for severe/damaging winds. This activity should weaken by late evening into WI and northern IL as it encounters a less unstable airmass. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Thu Jul 04 2024 Valid 042000Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE UPPER MISSISSIPPI VALLEY...AND FROM THE SOUTHERN PLAINS TO THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms will be possible through this evening across parts of the upper Mississippi Valley, and from the southern Plains to the lower Ohio Valley. ...20z Update... Severe probabilities have been trimmed across parts of MN/IA in-line with the current location of the surface cold front. Otherwise, only minor changes have been made to the 10 percent general thunderstorm line. Overall forecast thinking remains similar to the previous outlook. However, coverage of severe storms across parts of southern IL into the Ohio Valley (outside of WW 505) is uncertain the remainder of the period. However, a very moist and unstable airmass resides across the area. Additional storms may develop this evening/overnight along the surface front, and any other storms that can develop through evening would pose severe gust potential, precluding a downgrade in probabilities at this time. For information on short term severe potential across the Upper MS Valley and the southern Plains, reference MCDS 1534 and 1535. ..Leitman.. 07/04/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Thu Jul 04 2024/ ...Synopsis... An upper trough over the northern/central Plains will move generally eastward today across the Upper Midwest and mid MS Valley. A separate, convectively augmented mid-level vorticity maximum is present over southern IA/northern MO late this morning. This MCV and associated convection across the OH Valley will move east-northeastward across the OH Valley/Midwest through this evening. At the surface, a weak low should develop eastward across parts of the Upper Midwest in tandem with the large-scale upper trough. Another weak surface low should also track northeastward over the OH Valley with the remnant MCV. A convectively reinforced front draped from the southern Plains northeastward into the mid MS and OH Valleys will likely serve as a focus for strong to severe thunderstorms this afternoon and evening. ...Mid Mississippi Valley into the Ohio Valley and Mid-Atlantic... Mostly elevated thunderstorms are ongoing late this morning across the lower OH Valley. The rather moist low-level airmass along/south of a front will continue to gradually destabilize through the afternoon. Although mid-level lapse rates will remain poor, moderate instability has already developed downstream of activity moving across southern IN and western KY. Additional intensification of this convection will probably occur through early afternoon across parts of central/eastern KY and perhaps southern OH ahead of the MCV. Even though stronger mid-level flow may tend to remain displaced to the north of the front, modest but sufficient deep-layer shear should be present to support multicell clustering. Scattered damaging winds occasionally reaching severe thresholds should be the main threat with this activity as it spreads eastward across the lower OH Valley this afternoon and evening. Low-level flow is forecast to remain generally modest and veered to southwesterly. Still, sufficient speed shear will be present to support some threat for updraft rotation and perhaps a tornado or two, especially if any supercells can develop and persist. Isolated hail may also occur with more robust cores. Confidence in strong convection moving off the Blue Ridge Mountains in the Mid-Atlantic is relatively low. But, any thunderstorms that do form across this region could produce locally damaging winds. ...Southern Plains to the Ozarks... The portion of the cold front extending across the southern Plains into the Ozarks is forecast to make only slow southward progress through this evening. Even with some mid/high-level clouds persisting across these areas, robust daytime heating along/south of the front will likely encourage surface temperatures to warm into the 90s and low 100s. Even though low/mid-level flow will remain fairly weak, rather large surface temperature/dewpoint spreads (up to 30-40 degrees F) and steepened low-level lapse rates should foster a threat for mainly severe/damaging winds with any thunderstorms that can develop this afternoon and evening. Robust convection appears probable along/near the front by 22-00Z, and there appears to be some potential for an organized cluster to develop over the Ozarks/southern MO vicinity and sweep east-southeastward through the late evening. ...Upper Mississippi Valley... A focused area of ascent associated with the upper trough will overspread southern MN and northern IA today. While cloud cover remains prevalent over much of this region late this morning, there has been some recent clearing on the western edge of the cloud deck. A relatively small area of modest destabilization is still anticipated, with MLCAPE around 1000-1500 J/kg possible. A 45-60 kt mid-level jet attendant to the upper trough will overspread the developing warm sector through the afternoon. This jet will aid sufficiently strong deep-layer shear to support supercells with an associated threat for severe hail. Some clustering/upscale growth may eventually occur, which would support a greater threat for severe/damaging winds. This activity should weaken by late evening into WI and northern IL as it encounters a less unstable airmass. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Thu Jul 04 2024 Valid 042000Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE UPPER MISSISSIPPI VALLEY...AND FROM THE SOUTHERN PLAINS TO THE OHIO VALLEY... ...SUMMARY... Scattered severe thunderstorms will be possible through this evening across parts of the upper Mississippi Valley, and from the southern Plains to the lower Ohio Valley. ...20z Update... Severe probabilities have been trimmed across parts of MN/IA in-line with the current location of the surface cold front. Otherwise, only minor changes have been made to the 10 percent general thunderstorm line. Overall forecast thinking remains similar to the previous outlook. However, coverage of severe storms across parts of southern IL into the Ohio Valley (outside of WW 505) is uncertain the remainder of the period. However, a very moist and unstable airmass resides across the area. Additional storms may develop this evening/overnight along the surface front, and any other storms that can develop through evening would pose severe gust potential, precluding a downgrade in probabilities at this time. For information on short term severe potential across the Upper MS Valley and the southern Plains, reference MCDS 1534 and 1535. ..Leitman.. 07/04/2024 .PREV DISCUSSION... /ISSUED 1130 AM CDT Thu Jul 04 2024/ ...Synopsis... An upper trough over the northern/central Plains will move generally eastward today across the Upper Midwest and mid MS Valley. A separate, convectively augmented mid-level vorticity maximum is present over southern IA/northern MO late this morning. This MCV and associated convection across the OH Valley will move east-northeastward across the OH Valley/Midwest through this evening. At the surface, a weak low should develop eastward across parts of the Upper Midwest in tandem with the large-scale upper trough. Another weak surface low should also track northeastward over the OH Valley with the remnant MCV. A convectively reinforced front draped from the southern Plains northeastward into the mid MS and OH Valleys will likely serve as a focus for strong to severe thunderstorms this afternoon and evening. ...Mid Mississippi Valley into the Ohio Valley and Mid-Atlantic... Mostly elevated thunderstorms are ongoing late this morning across the lower OH Valley. The rather moist low-level airmass along/south of a front will continue to gradually destabilize through the afternoon. Although mid-level lapse rates will remain poor, moderate instability has already developed downstream of activity moving across southern IN and western KY. Additional intensification of this convection will probably occur through early afternoon across parts of central/eastern KY and perhaps southern OH ahead of the MCV. Even though stronger mid-level flow may tend to remain displaced to the north of the front, modest but sufficient deep-layer shear should be present to support multicell clustering. Scattered damaging winds occasionally reaching severe thresholds should be the main threat with this activity as it spreads eastward across the lower OH Valley this afternoon and evening. Low-level flow is forecast to remain generally modest and veered to southwesterly. Still, sufficient speed shear will be present to support some threat for updraft rotation and perhaps a tornado or two, especially if any supercells can develop and persist. Isolated hail may also occur with more robust cores. Confidence in strong convection moving off the Blue Ridge Mountains in the Mid-Atlantic is relatively low. But, any thunderstorms that do form across this region could produce locally damaging winds. ...Southern Plains to the Ozarks... The portion of the cold front extending across the southern Plains into the Ozarks is forecast to make only slow southward progress through this evening. Even with some mid/high-level clouds persisting across these areas, robust daytime heating along/south of the front will likely encourage surface temperatures to warm into the 90s and low 100s. Even though low/mid-level flow will remain fairly weak, rather large surface temperature/dewpoint spreads (up to 30-40 degrees F) and steepened low-level lapse rates should foster a threat for mainly severe/damaging winds with any thunderstorms that can develop this afternoon and evening. Robust convection appears probable along/near the front by 22-00Z, and there appears to be some potential for an organized cluster to develop over the Ozarks/southern MO vicinity and sweep east-southeastward through the late evening. ...Upper Mississippi Valley... A focused area of ascent associated with the upper trough will overspread southern MN and northern IA today. While cloud cover remains prevalent over much of this region late this morning, there has been some recent clearing on the western edge of the cloud deck. A relatively small area of modest destabilization is still anticipated, with MLCAPE around 1000-1500 J/kg possible. A 45-60 kt mid-level jet attendant to the upper trough will overspread the developing warm sector through the afternoon. This jet will aid sufficiently strong deep-layer shear to support supercells with an associated threat for severe hail. Some clustering/upscale growth may eventually occur, which would support a greater threat for severe/damaging winds. This activity should weaken by late evening into WI and northern IL as it encounters a less unstable airmass. Read more

WW 0505 Status Updates
STATUS REPORT ON WW 505 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 E OWB TO 20 SSE SDF TO 35 ESE LUK. ..MOORE..07/04/24 ATTN...WFO...LMK...JKL...ILN... STATUS REPORT FOR WS 505 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS KYC005-011-017-021-023-025-049-063-065-067-069-073-079-085-093- 097-109-113-123-129-135-151-153-155-161-165-167-173-175-179-181- 189-197-201-205-209-215-229-237-239-042040- KY . KENTUCKY COUNTIES INCLUDED ARE ANDERSON BATH BOURBON BOYLE BRACKEN BREATHITT CLARK ELLIOTT ESTILL FAYETTE FLEMING FRANKLIN GARRARD GRAYSON HARDIN HARRISON JACKSON JESSAMINE LARUE LEE LEWIS MADISON MAGOFFIN MARION MASON MENIFEE MERCER MONTGOMERY MORGAN NELSON NICHOLAS OWSLEY POWELL ROBERTSON ROWAN SCOTT SPENCER WASHINGTON WOLFE WOODFORD THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL Read more

MD 1533 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR NORTHERN KENTUCKY...FAR SOUTHERN INDIANA
Mesoscale Discussion 1533 NWS Storm Prediction Center Norman OK 1130 AM CDT Thu Jul 04 2024 Areas affected...northern Kentucky...far southern Indiana Concerning...Severe potential...Watch possible Valid 041630Z - 041900Z Probability of Watch Issuance...60 percent SUMMARY...A corridor of scattered damaging gusts or marginal hail potential exists over much of central and northern Kentucky and toward the Ohio River. DISCUSSION...Within a weak surface trough and on the southern periphery of the earlier rain/outflow, an extremely moist air mass continues to heat and destabilize. Mid 70s F dewpoints exist along with GPW PWAT values over 2.25". Meanwhile, strong heating exists south of the outflow/frontal zone, with warming into the lower 90s F. Primarily westerly flow exists across the area, except west/southwest within the boundary layer. As such, little northward movement in the existing surface theta-e gradient is anticipated over the next few hours. VWPs indicate 35+ kt speeds at 700 mb, with around 50 kt at 500 mb. As a result, developing robust storms now over southern IN and western KY are likely to intensify and perhaps expand a bit in N/S coverage through the afternoon. Ample PWAT to support downbursts, steepening low-level lapse rates, and favorable low to midlevel mean wind speeds all support a developing damaging wind threat, and a watch may be needed. ..Jewell/Gleason.. 07/04/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...RLX...JKL...ILN...LMK...PAH... LAT...LON 37518361 37558684 37578711 37638730 37978688 38348659 38598628 38748569 38768439 38778332 38438292 37988290 37648298 37518361 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0143 PM CDT Thu Jul 04 2024 Valid 051200Z - 061200Z ...Northwest and northern Great Basin... Confidence has increased that a period of gusty winds (15-20 mph) could develop across portions of the southern and western Snake River Valley in ID. Concurrent with very warm temperatures and low RH below 15%, several hours of elevated to near-critical fire-weather conditions appear likely atop dry fuels. A small Elevated area has been added to better represent the risk for near-critical fire-weather concerns Friday afternoon and evening. Similarly across the lee of the Cascades and parts of the western Columbia Basin, increasing mid-level flow will foster periodically stronger downslope winds Friday afternoon and evening. Gusts of 15-20 mph may briefly overlap with RH below 20%. However, the strongest winds aloft are likely to be overnight and poorly timed with the lowest RH. While a few hours of dry and breezy conditions appear possible, the lack of greater overlap should keep the fire-weather threat localized. ..Lyons.. 07/04/2024 .PREV DISCUSSION... /ISSUED 0143 AM CDT Thu Jul 04 2024/ ...Synopsis... Similar conditions present over the Interior West today should also occur again for tomorrow (Friday). A mid-level trough will remain in place over the Plains/Mississippi Valley areas as a mid-level anticyclone meanders along the West Coast. Widespread dry conditions (i.e. 10-20 percent RH) should be prevalent by afternoon from the Pacific Northwest to the Desert Southwest. Still, sustained surface winds should remain below 15 mph on the large scale, though terrain-favoring areas may experience localized Elevated 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 0143 PM CDT Thu Jul 04 2024 Valid 051200Z - 061200Z ...Northwest and northern Great Basin... Confidence has increased that a period of gusty winds (15-20 mph) could develop across portions of the southern and western Snake River Valley in ID. Concurrent with very warm temperatures and low RH below 15%, several hours of elevated to near-critical fire-weather conditions appear likely atop dry fuels. A small Elevated area has been added to better represent the risk for near-critical fire-weather concerns Friday afternoon and evening. Similarly across the lee of the Cascades and parts of the western Columbia Basin, increasing mid-level flow will foster periodically stronger downslope winds Friday afternoon and evening. Gusts of 15-20 mph may briefly overlap with RH below 20%. However, the strongest winds aloft are likely to be overnight and poorly timed with the lowest RH. While a few hours of dry and breezy conditions appear possible, the lack of greater overlap should keep the fire-weather threat localized. ..Lyons.. 07/04/2024 .PREV DISCUSSION... /ISSUED 0143 AM CDT Thu Jul 04 2024/ ...Synopsis... Similar conditions present over the Interior West today should also occur again for tomorrow (Friday). A mid-level trough will remain in place over the Plains/Mississippi Valley areas as a mid-level anticyclone meanders along the West Coast. Widespread dry conditions (i.e. 10-20 percent RH) should be prevalent by afternoon from the Pacific Northwest to the Desert Southwest. Still, sustained surface winds should remain below 15 mph on the large scale, though terrain-favoring areas may experience localized Elevated conditions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more