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SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0748 AM CDT Sat May 17 2025 Valid 171300Z - 181200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS NORTH TEXAS AND SOUTHERN OKLAHOMA... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF UPSTATE NEW YORK AND WESTERN NEW ENGLAND... ...SUMMARY... Severe thunderstorms producing large to very large hail, damaging gusts and a couple of tornadoes are expected across the southern Plains. Additional severe storms are possible across the Northeast. ...Southern Plains Region... Water vapor imagery depicts a pronounced southern stream upper-level trough over the Baja Peninsula this morning, with evidence of a lead impulse approaching southwest TX. This leading impulse will contribute to ascent in the vicinity of a sharpening dryline across Western North Texas/Oklahoma by early afternoon. To the east of the dryline, extreme instability (MLCAPE in excess of 4000 J/kg) is expected to develop given the moist low-level air mass and relatively cool mid-level thermal profiles. With negligible CINH by early/mid afternoon, thunderstorms are expected to develop along the dryline and move east/northeast into North Texas and southern Oklahoma. Supercells will be the dominant mode initially, with a risk for very large hail (in excess of 3.5 inches), and damaging gusts. Although low-level shear is not especially strong, some tornado risk will exist given the magnitude of instability and potential for storm-scale interactions. Eventual upscale growth into a severe MCS is expected as storms continue to move across North TX/southern OK this evening. Severe wind probabilities have been increased across the Enhanced Risk area for the expectation of a more concentrated corridor of damaging wind potential. Across central/northwest OK, a narrowing plume of instability will be present east of the dryline and south of an east-west oriented frontal boundary. Within this moist sector, strong to extreme instability and around 50 kts of deep-layer shear will support at least isolated supercell storm development this afternoon over central OK. Very large hail (3 inches or greater) will be possible, in addition to damaging gusts. Tornado risk will be dependent on storm interactions. Thunderstorm development over northwest OK is more uncertain, however should a storm develop a supercell mode will be favored with all hazards possible. ...Northeast... Strong mid-level height falls will spread across much of the northeastern U.S. today in response to the approaching Great Lakes upper low. Large-scale ascent will increase with as the left-exit region of the 500mb jet translates across PA. Scattered thunderstorms, including supercells, are expected to develop along/ahead of the synoptic cold front across upstate NY, with subsequent movement expected into western New England. Multiple rounds of thunderstorms are likely, with severe hail and winds as the primary risks. A tornado or two cannot be ruled out with any stronger and semi-discrete supercell. Please refer to Mesoscale Discussion 836 for additional details on short-term expectations. ...Northern Utah Vicinity... A Marginal Risk has been introduced across northern UT and vicinity given expected higher concentration of storms within a deeply-mixed boundary layer. Strong/severe gusts will be the primary severe risk. ...Lower Mississippi Valley/Southeast... Thunderstorms continue from central MS into the western Carolinas at 13z, with occasional pulses of strong/severe cells. Isolated stronger storms will remain possible as diurnal heating/destabilization takes place in the presence of ample shear for organized storms. However, with the line of convection oriented generally parallel to the shear vector, any severe risk should be isolated. Strong gusts will be the primary hazard. ..Bunting/Marsh.. 05/17/2025 Read more

MD 0835 CONCERNING SEVERE THUNDERSTORM WATCH 276... FOR FAR NORTHEAST SOUTH CAROLINA INTO SOUTH-CENTRAL VIRGINIA
Mesoscale Discussion 0835 NWS Storm Prediction Center Norman OK 0551 AM CDT Sat May 17 2025 Areas affected...far northeast South Carolina into south-central Virginia Concerning...Severe Thunderstorm Watch 276... Valid 171051Z - 171215Z The severe weather threat for Severe Thunderstorm Watch 276 continues. SUMMARY...Showers and thunderstorms continue across the region. In the short-term the most imminent severe threat is across southern portions of the watch. Unless new development occurs soon, northern portions of the watch may be canceled early. DISCUSSION...Despite increasing instability within a strongly sheared environment, the general thunderstorm intensity trend continues to decrease across much of the watch area. The exceptions to this trend are a couple of stronger cores across portions of far northern South Carolina and far southern North Carolina. Here, small hail and isolated wind damage threat should persist for at least another hour as the storms move through a relative minimum in instability. Should these storms survive this trek and reach central/eastern portions of the NC/SC line, an increasingly unstable airmass may support reintensification and a renewed severe threat. Elsewhere, most thunderstorms have dissipated with a widespread stratiform rain shield taking their place. However, recent radar imagery suggests the development of convective showers/storms developing across central North Carolina. Should these showers/storms continue to strengthen/mature, the overall environment will support gusty winds and isolated large hail. However, if these storms are unable to persist, the severe threat should continue to weaken and northern portions of the watch may be canceled early. ..Marsh.. 05/17/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...AKQ...RAH...RNK...CAE...GSP... LAT...LON 34988299 37057974 37057685 34998017 34988299 MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

MD 0834 CONCERNING SEVERE THUNDERSTORM WATCH 275... FOR NORTHERN MISSISSIPPI AND CENTRAL/NORTHERN ALABAMA
Mesoscale Discussion 0834 NWS Storm Prediction Center Norman OK 0533 AM CDT Sat May 17 2025 Areas affected...Northern Mississippi and central/northern Alabama Concerning...Severe Thunderstorm Watch 275... Valid 171033Z - 171200Z The severe weather threat for Severe Thunderstorm Watch 275 continues. SUMMARY...Long-lived thunderstorm clusters continue east across northern Mississippi and central Alabama. Isolated hail and strong winds remain possible. DISCUSSION...A long-lived, leading thunderstorm capable of hail and strong winds continues to move across central Alabama this morning. To the west, a line of additional thunderstorms stretches back into southeast Arkansas. A couple of stronger cores across central Alabama appear to have been able to tap into the substantial CAPE reservoir (MUCAPE greater than 2000 J/kg) along and just south of these thunderstorms. Deep-layer shear remains strong as well. As we approach the diurnal minimum in convection, the overall tendency of these thunderstorms should be to continue their downward intensity trend. That said, the overall environment is still supportive of at least episodic pulses of severe potential and thus additional instances of severe hail or wind cannot be ruled out. A local extension of Severe Thunderstorm Watch #275 may be needed across central Alabama to the south of the west-to-east, southward sagging linear MCS should convective intensity within the line ticks up. Elsewhere, trends will continue to be monitored for possible early cancellation of portions of the watch. ..Marsh.. 05/17/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FFC...BMX...HUN...MEG...JAN... LAT...LON 33519057 34858558 33108564 32858986 33519057 MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

000
ABPZ20 KNHC 171123
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 AM PDT Sat May 17 2025

For the eastern North Pacific...east of 140 degrees west longitude:

Tropical cyclone formation is not expected during the next 7 days.

$$
Forecaster Bucci

MD 0833 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR NORTHERN GEORGIA NORTHEAST INTO SOUTHERN VIRGINIA
Mesoscale Discussion 0833 NWS Storm Prediction Center Norman OK 0218 AM CDT Sat May 17 2025 Areas affected...northern Georgia northeast into southern Virginia Concerning...Severe potential...Watch possible Valid 170718Z - 170845Z Probability of Watch Issuance...60 percent SUMMARY...A long-lived thunderstorm complex continues to move south and east this morning. Strong thunderstorm winds, hail, and a tornado or two remain possible with the strongest thunderstorm cores. A new watch or watches may be needed downstream from existing watches. DISCUSSION...A long-lived linear MCS continues to move south and east this morning across the region with more isolated/cellular convection develop ahead of the line. This line has a history of producing wind damage across portions of east Tennessee. The portion of the line across Tennessee, Virginia, and North Carolina appears to be moving through a minimum in favorability for severe thunderstorms. Here MUCAPE is only about 1000 J/KG, although deep-layer shear remains more than sufficient at greater than 50 knots. Ahead of this portion of the line, the environment actually improves to the east as MUCAPE increases to nearly 2500 J/kg across central Virginia. Given the increasingly favorable-for-severe environment downstream of the existing line, a new watch may become necessary across western North Carolina and southern Virginia. Farther southwest, more uncertainty for severe potential exists. Convective cells have become oriented more parallel to the large-scale shear vectors. This has resulted in less downward momentum transfer and slowed the advancement of the line. As the multitude of individual cells within the linear MCS continue to interfere with one another, robust thunderstorm updrafts capable of producing large hail and damaging winds has been limited. Despite this, the overall large-scale environment will remain conducive for episodic severe potential and thus the area will also be monitored for watch potential. ..Marsh/Bunting.. 05/17/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...RNK...GSP...MRX...FFC... LAT...LON 37268118 37147926 36238050 34918282 34318520 35528546 36368286 37268118 MOST PROBABLE PEAK TORNADO INTENSITY...100-130 MPH MOST PROBABLE PEAK WIND GUST...65-80 MPH MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CDT Sat May 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Tuesday... As the primary mid-level trough shifts east on Tuesday, scattered severe thunderstorms are likely across parts of the Mid-Mississippi Valley into the Tennessee Valley. Upper 60s to low 70s dewpoints will be present ahead of a cold front. Convection/cloud cover from Day 3 convection across the Plains/Ozarks will impact destabilization across Kentucky and into the Ohio Valley. However, farther south, strong destabilization is likely as the boundary layer heats beneath steepening mid-level lapse rates. 50 to 60 knots of mid-level flow will overspread this unstable warm sector during the afternoon Tuesday. As this occurs, an uncapped boundary layer and synoptic scale ascent should combine for scattered severe storm development. Wherever moderate to strong instability develops, most likely south of the TN/KY border, supercells are anticipated with a primary threat for large hail. By later in the evening, storms may congeal into a MCS with an increasing damaging wind threat. ...Day 5/Wednesday... A cold front will advance across the Appalachians on Tuesday night/Wednesday morning. Moderate instability is forecast ahead of this cold front Wednesday morning/early afternoon. A few strong to severe storms may develop along the front before it moves into the Atlantic. However, the limited duration of this threat, and potential for timing shifts as newer guidance arrives, precludes severe weather probabilities at this time. ...Day6-8.. A relatively benign severe weather pattern is expected from Thursday/Day 6 into next weekend as a cold front pushes into the Gulf. A few storms are possible along the cold front as it moves south along the Florida Peninsula on Thursday. Otherwise, more robust moisture recovery will begin Thursday night. Overall, moisture quality will be low initially, but eventually some threat may develop across the Plains as low-level moisture advection continues. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CDT Sat May 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Tuesday... As the primary mid-level trough shifts east on Tuesday, scattered severe thunderstorms are likely across parts of the Mid-Mississippi Valley into the Tennessee Valley. Upper 60s to low 70s dewpoints will be present ahead of a cold front. Convection/cloud cover from Day 3 convection across the Plains/Ozarks will impact destabilization across Kentucky and into the Ohio Valley. However, farther south, strong destabilization is likely as the boundary layer heats beneath steepening mid-level lapse rates. 50 to 60 knots of mid-level flow will overspread this unstable warm sector during the afternoon Tuesday. As this occurs, an uncapped boundary layer and synoptic scale ascent should combine for scattered severe storm development. Wherever moderate to strong instability develops, most likely south of the TN/KY border, supercells are anticipated with a primary threat for large hail. By later in the evening, storms may congeal into a MCS with an increasing damaging wind threat. ...Day 5/Wednesday... A cold front will advance across the Appalachians on Tuesday night/Wednesday morning. Moderate instability is forecast ahead of this cold front Wednesday morning/early afternoon. A few strong to severe storms may develop along the front before it moves into the Atlantic. However, the limited duration of this threat, and potential for timing shifts as newer guidance arrives, precludes severe weather probabilities at this time. ...Day6-8.. A relatively benign severe weather pattern is expected from Thursday/Day 6 into next weekend as a cold front pushes into the Gulf. A few storms are possible along the cold front as it moves south along the Florida Peninsula on Thursday. Otherwise, more robust moisture recovery will begin Thursday night. Overall, moisture quality will be low initially, but eventually some threat may develop across the Plains as low-level moisture advection continues. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CDT Sat May 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Tuesday... As the primary mid-level trough shifts east on Tuesday, scattered severe thunderstorms are likely across parts of the Mid-Mississippi Valley into the Tennessee Valley. Upper 60s to low 70s dewpoints will be present ahead of a cold front. Convection/cloud cover from Day 3 convection across the Plains/Ozarks will impact destabilization across Kentucky and into the Ohio Valley. However, farther south, strong destabilization is likely as the boundary layer heats beneath steepening mid-level lapse rates. 50 to 60 knots of mid-level flow will overspread this unstable warm sector during the afternoon Tuesday. As this occurs, an uncapped boundary layer and synoptic scale ascent should combine for scattered severe storm development. Wherever moderate to strong instability develops, most likely south of the TN/KY border, supercells are anticipated with a primary threat for large hail. By later in the evening, storms may congeal into a MCS with an increasing damaging wind threat. ...Day 5/Wednesday... A cold front will advance across the Appalachians on Tuesday night/Wednesday morning. Moderate instability is forecast ahead of this cold front Wednesday morning/early afternoon. A few strong to severe storms may develop along the front before it moves into the Atlantic. However, the limited duration of this threat, and potential for timing shifts as newer guidance arrives, precludes severe weather probabilities at this time. ...Day6-8.. A relatively benign severe weather pattern is expected from Thursday/Day 6 into next weekend as a cold front pushes into the Gulf. A few storms are possible along the cold front as it moves south along the Florida Peninsula on Thursday. Otherwise, more robust moisture recovery will begin Thursday night. Overall, moisture quality will be low initially, but eventually some threat may develop across the Plains as low-level moisture advection continues. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CDT Sat May 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Tuesday... As the primary mid-level trough shifts east on Tuesday, scattered severe thunderstorms are likely across parts of the Mid-Mississippi Valley into the Tennessee Valley. Upper 60s to low 70s dewpoints will be present ahead of a cold front. Convection/cloud cover from Day 3 convection across the Plains/Ozarks will impact destabilization across Kentucky and into the Ohio Valley. However, farther south, strong destabilization is likely as the boundary layer heats beneath steepening mid-level lapse rates. 50 to 60 knots of mid-level flow will overspread this unstable warm sector during the afternoon Tuesday. As this occurs, an uncapped boundary layer and synoptic scale ascent should combine for scattered severe storm development. Wherever moderate to strong instability develops, most likely south of the TN/KY border, supercells are anticipated with a primary threat for large hail. By later in the evening, storms may congeal into a MCS with an increasing damaging wind threat. ...Day 5/Wednesday... A cold front will advance across the Appalachians on Tuesday night/Wednesday morning. Moderate instability is forecast ahead of this cold front Wednesday morning/early afternoon. A few strong to severe storms may develop along the front before it moves into the Atlantic. However, the limited duration of this threat, and potential for timing shifts as newer guidance arrives, precludes severe weather probabilities at this time. ...Day6-8.. A relatively benign severe weather pattern is expected from Thursday/Day 6 into next weekend as a cold front pushes into the Gulf. A few storms are possible along the cold front as it moves south along the Florida Peninsula on Thursday. Otherwise, more robust moisture recovery will begin Thursday night. Overall, moisture quality will be low initially, but eventually some threat may develop across the Plains as low-level moisture advection continues. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CDT Sat May 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Tuesday... As the primary mid-level trough shifts east on Tuesday, scattered severe thunderstorms are likely across parts of the Mid-Mississippi Valley into the Tennessee Valley. Upper 60s to low 70s dewpoints will be present ahead of a cold front. Convection/cloud cover from Day 3 convection across the Plains/Ozarks will impact destabilization across Kentucky and into the Ohio Valley. However, farther south, strong destabilization is likely as the boundary layer heats beneath steepening mid-level lapse rates. 50 to 60 knots of mid-level flow will overspread this unstable warm sector during the afternoon Tuesday. As this occurs, an uncapped boundary layer and synoptic scale ascent should combine for scattered severe storm development. Wherever moderate to strong instability develops, most likely south of the TN/KY border, supercells are anticipated with a primary threat for large hail. By later in the evening, storms may congeal into a MCS with an increasing damaging wind threat. ...Day 5/Wednesday... A cold front will advance across the Appalachians on Tuesday night/Wednesday morning. Moderate instability is forecast ahead of this cold front Wednesday morning/early afternoon. A few strong to severe storms may develop along the front before it moves into the Atlantic. However, the limited duration of this threat, and potential for timing shifts as newer guidance arrives, precludes severe weather probabilities at this time. ...Day6-8.. A relatively benign severe weather pattern is expected from Thursday/Day 6 into next weekend as a cold front pushes into the Gulf. A few storms are possible along the cold front as it moves south along the Florida Peninsula on Thursday. Otherwise, more robust moisture recovery will begin Thursday night. Overall, moisture quality will be low initially, but eventually some threat may develop across the Plains as low-level moisture advection continues. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CDT Sat May 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Tuesday... As the primary mid-level trough shifts east on Tuesday, scattered severe thunderstorms are likely across parts of the Mid-Mississippi Valley into the Tennessee Valley. Upper 60s to low 70s dewpoints will be present ahead of a cold front. Convection/cloud cover from Day 3 convection across the Plains/Ozarks will impact destabilization across Kentucky and into the Ohio Valley. However, farther south, strong destabilization is likely as the boundary layer heats beneath steepening mid-level lapse rates. 50 to 60 knots of mid-level flow will overspread this unstable warm sector during the afternoon Tuesday. As this occurs, an uncapped boundary layer and synoptic scale ascent should combine for scattered severe storm development. Wherever moderate to strong instability develops, most likely south of the TN/KY border, supercells are anticipated with a primary threat for large hail. By later in the evening, storms may congeal into a MCS with an increasing damaging wind threat. ...Day 5/Wednesday... A cold front will advance across the Appalachians on Tuesday night/Wednesday morning. Moderate instability is forecast ahead of this cold front Wednesday morning/early afternoon. A few strong to severe storms may develop along the front before it moves into the Atlantic. However, the limited duration of this threat, and potential for timing shifts as newer guidance arrives, precludes severe weather probabilities at this time. ...Day6-8.. A relatively benign severe weather pattern is expected from Thursday/Day 6 into next weekend as a cold front pushes into the Gulf. A few storms are possible along the cold front as it moves south along the Florida Peninsula on Thursday. Otherwise, more robust moisture recovery will begin Thursday night. Overall, moisture quality will be low initially, but eventually some threat may develop across the Plains as low-level moisture advection continues. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CDT Sat May 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Tuesday... As the primary mid-level trough shifts east on Tuesday, scattered severe thunderstorms are likely across parts of the Mid-Mississippi Valley into the Tennessee Valley. Upper 60s to low 70s dewpoints will be present ahead of a cold front. Convection/cloud cover from Day 3 convection across the Plains/Ozarks will impact destabilization across Kentucky and into the Ohio Valley. However, farther south, strong destabilization is likely as the boundary layer heats beneath steepening mid-level lapse rates. 50 to 60 knots of mid-level flow will overspread this unstable warm sector during the afternoon Tuesday. As this occurs, an uncapped boundary layer and synoptic scale ascent should combine for scattered severe storm development. Wherever moderate to strong instability develops, most likely south of the TN/KY border, supercells are anticipated with a primary threat for large hail. By later in the evening, storms may congeal into a MCS with an increasing damaging wind threat. ...Day 5/Wednesday... A cold front will advance across the Appalachians on Tuesday night/Wednesday morning. Moderate instability is forecast ahead of this cold front Wednesday morning/early afternoon. A few strong to severe storms may develop along the front before it moves into the Atlantic. However, the limited duration of this threat, and potential for timing shifts as newer guidance arrives, precludes severe weather probabilities at this time. ...Day6-8.. A relatively benign severe weather pattern is expected from Thursday/Day 6 into next weekend as a cold front pushes into the Gulf. A few storms are possible along the cold front as it moves south along the Florida Peninsula on Thursday. Otherwise, more robust moisture recovery will begin Thursday night. Overall, moisture quality will be low initially, but eventually some threat may develop across the Plains as low-level moisture advection continues. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CDT Sat May 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Tuesday... As the primary mid-level trough shifts east on Tuesday, scattered severe thunderstorms are likely across parts of the Mid-Mississippi Valley into the Tennessee Valley. Upper 60s to low 70s dewpoints will be present ahead of a cold front. Convection/cloud cover from Day 3 convection across the Plains/Ozarks will impact destabilization across Kentucky and into the Ohio Valley. However, farther south, strong destabilization is likely as the boundary layer heats beneath steepening mid-level lapse rates. 50 to 60 knots of mid-level flow will overspread this unstable warm sector during the afternoon Tuesday. As this occurs, an uncapped boundary layer and synoptic scale ascent should combine for scattered severe storm development. Wherever moderate to strong instability develops, most likely south of the TN/KY border, supercells are anticipated with a primary threat for large hail. By later in the evening, storms may congeal into a MCS with an increasing damaging wind threat. ...Day 5/Wednesday... A cold front will advance across the Appalachians on Tuesday night/Wednesday morning. Moderate instability is forecast ahead of this cold front Wednesday morning/early afternoon. A few strong to severe storms may develop along the front before it moves into the Atlantic. However, the limited duration of this threat, and potential for timing shifts as newer guidance arrives, precludes severe weather probabilities at this time. ...Day6-8.. A relatively benign severe weather pattern is expected from Thursday/Day 6 into next weekend as a cold front pushes into the Gulf. A few storms are possible along the cold front as it moves south along the Florida Peninsula on Thursday. Otherwise, more robust moisture recovery will begin Thursday night. Overall, moisture quality will be low initially, but eventually some threat may develop across the Plains as low-level moisture advection continues. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CDT Sat May 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Tuesday... As the primary mid-level trough shifts east on Tuesday, scattered severe thunderstorms are likely across parts of the Mid-Mississippi Valley into the Tennessee Valley. Upper 60s to low 70s dewpoints will be present ahead of a cold front. Convection/cloud cover from Day 3 convection across the Plains/Ozarks will impact destabilization across Kentucky and into the Ohio Valley. However, farther south, strong destabilization is likely as the boundary layer heats beneath steepening mid-level lapse rates. 50 to 60 knots of mid-level flow will overspread this unstable warm sector during the afternoon Tuesday. As this occurs, an uncapped boundary layer and synoptic scale ascent should combine for scattered severe storm development. Wherever moderate to strong instability develops, most likely south of the TN/KY border, supercells are anticipated with a primary threat for large hail. By later in the evening, storms may congeal into a MCS with an increasing damaging wind threat. ...Day 5/Wednesday... A cold front will advance across the Appalachians on Tuesday night/Wednesday morning. Moderate instability is forecast ahead of this cold front Wednesday morning/early afternoon. A few strong to severe storms may develop along the front before it moves into the Atlantic. However, the limited duration of this threat, and potential for timing shifts as newer guidance arrives, precludes severe weather probabilities at this time. ...Day6-8.. A relatively benign severe weather pattern is expected from Thursday/Day 6 into next weekend as a cold front pushes into the Gulf. A few storms are possible along the cold front as it moves south along the Florida Peninsula on Thursday. Otherwise, more robust moisture recovery will begin Thursday night. Overall, moisture quality will be low initially, but eventually some threat may develop across the Plains as low-level moisture advection continues. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CDT Sat May 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Tuesday... As the primary mid-level trough shifts east on Tuesday, scattered severe thunderstorms are likely across parts of the Mid-Mississippi Valley into the Tennessee Valley. Upper 60s to low 70s dewpoints will be present ahead of a cold front. Convection/cloud cover from Day 3 convection across the Plains/Ozarks will impact destabilization across Kentucky and into the Ohio Valley. However, farther south, strong destabilization is likely as the boundary layer heats beneath steepening mid-level lapse rates. 50 to 60 knots of mid-level flow will overspread this unstable warm sector during the afternoon Tuesday. As this occurs, an uncapped boundary layer and synoptic scale ascent should combine for scattered severe storm development. Wherever moderate to strong instability develops, most likely south of the TN/KY border, supercells are anticipated with a primary threat for large hail. By later in the evening, storms may congeal into a MCS with an increasing damaging wind threat. ...Day 5/Wednesday... A cold front will advance across the Appalachians on Tuesday night/Wednesday morning. Moderate instability is forecast ahead of this cold front Wednesday morning/early afternoon. A few strong to severe storms may develop along the front before it moves into the Atlantic. However, the limited duration of this threat, and potential for timing shifts as newer guidance arrives, precludes severe weather probabilities at this time. ...Day6-8.. A relatively benign severe weather pattern is expected from Thursday/Day 6 into next weekend as a cold front pushes into the Gulf. A few storms are possible along the cold front as it moves south along the Florida Peninsula on Thursday. Otherwise, more robust moisture recovery will begin Thursday night. Overall, moisture quality will be low initially, but eventually some threat may develop across the Plains as low-level moisture advection continues. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CDT Sat May 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Tuesday... As the primary mid-level trough shifts east on Tuesday, scattered severe thunderstorms are likely across parts of the Mid-Mississippi Valley into the Tennessee Valley. Upper 60s to low 70s dewpoints will be present ahead of a cold front. Convection/cloud cover from Day 3 convection across the Plains/Ozarks will impact destabilization across Kentucky and into the Ohio Valley. However, farther south, strong destabilization is likely as the boundary layer heats beneath steepening mid-level lapse rates. 50 to 60 knots of mid-level flow will overspread this unstable warm sector during the afternoon Tuesday. As this occurs, an uncapped boundary layer and synoptic scale ascent should combine for scattered severe storm development. Wherever moderate to strong instability develops, most likely south of the TN/KY border, supercells are anticipated with a primary threat for large hail. By later in the evening, storms may congeal into a MCS with an increasing damaging wind threat. ...Day 5/Wednesday... A cold front will advance across the Appalachians on Tuesday night/Wednesday morning. Moderate instability is forecast ahead of this cold front Wednesday morning/early afternoon. A few strong to severe storms may develop along the front before it moves into the Atlantic. However, the limited duration of this threat, and potential for timing shifts as newer guidance arrives, precludes severe weather probabilities at this time. ...Day6-8.. A relatively benign severe weather pattern is expected from Thursday/Day 6 into next weekend as a cold front pushes into the Gulf. A few storms are possible along the cold front as it moves south along the Florida Peninsula on Thursday. Otherwise, more robust moisture recovery will begin Thursday night. Overall, moisture quality will be low initially, but eventually some threat may develop across the Plains as low-level moisture advection continues. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CDT Sat May 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Tuesday... As the primary mid-level trough shifts east on Tuesday, scattered severe thunderstorms are likely across parts of the Mid-Mississippi Valley into the Tennessee Valley. Upper 60s to low 70s dewpoints will be present ahead of a cold front. Convection/cloud cover from Day 3 convection across the Plains/Ozarks will impact destabilization across Kentucky and into the Ohio Valley. However, farther south, strong destabilization is likely as the boundary layer heats beneath steepening mid-level lapse rates. 50 to 60 knots of mid-level flow will overspread this unstable warm sector during the afternoon Tuesday. As this occurs, an uncapped boundary layer and synoptic scale ascent should combine for scattered severe storm development. Wherever moderate to strong instability develops, most likely south of the TN/KY border, supercells are anticipated with a primary threat for large hail. By later in the evening, storms may congeal into a MCS with an increasing damaging wind threat. ...Day 5/Wednesday... A cold front will advance across the Appalachians on Tuesday night/Wednesday morning. Moderate instability is forecast ahead of this cold front Wednesday morning/early afternoon. A few strong to severe storms may develop along the front before it moves into the Atlantic. However, the limited duration of this threat, and potential for timing shifts as newer guidance arrives, precludes severe weather probabilities at this time. ...Day6-8.. A relatively benign severe weather pattern is expected from Thursday/Day 6 into next weekend as a cold front pushes into the Gulf. A few storms are possible along the cold front as it moves south along the Florida Peninsula on Thursday. Otherwise, more robust moisture recovery will begin Thursday night. Overall, moisture quality will be low initially, but eventually some threat may develop across the Plains as low-level moisture advection continues. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CDT Sat May 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Tuesday... As the primary mid-level trough shifts east on Tuesday, scattered severe thunderstorms are likely across parts of the Mid-Mississippi Valley into the Tennessee Valley. Upper 60s to low 70s dewpoints will be present ahead of a cold front. Convection/cloud cover from Day 3 convection across the Plains/Ozarks will impact destabilization across Kentucky and into the Ohio Valley. However, farther south, strong destabilization is likely as the boundary layer heats beneath steepening mid-level lapse rates. 50 to 60 knots of mid-level flow will overspread this unstable warm sector during the afternoon Tuesday. As this occurs, an uncapped boundary layer and synoptic scale ascent should combine for scattered severe storm development. Wherever moderate to strong instability develops, most likely south of the TN/KY border, supercells are anticipated with a primary threat for large hail. By later in the evening, storms may congeal into a MCS with an increasing damaging wind threat. ...Day 5/Wednesday... A cold front will advance across the Appalachians on Tuesday night/Wednesday morning. Moderate instability is forecast ahead of this cold front Wednesday morning/early afternoon. A few strong to severe storms may develop along the front before it moves into the Atlantic. However, the limited duration of this threat, and potential for timing shifts as newer guidance arrives, precludes severe weather probabilities at this time. ...Day6-8.. A relatively benign severe weather pattern is expected from Thursday/Day 6 into next weekend as a cold front pushes into the Gulf. A few storms are possible along the cold front as it moves south along the Florida Peninsula on Thursday. Otherwise, more robust moisture recovery will begin Thursday night. Overall, moisture quality will be low initially, but eventually some threat may develop across the Plains as low-level moisture advection continues. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CDT Sat May 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Tuesday... As the primary mid-level trough shifts east on Tuesday, scattered severe thunderstorms are likely across parts of the Mid-Mississippi Valley into the Tennessee Valley. Upper 60s to low 70s dewpoints will be present ahead of a cold front. Convection/cloud cover from Day 3 convection across the Plains/Ozarks will impact destabilization across Kentucky and into the Ohio Valley. However, farther south, strong destabilization is likely as the boundary layer heats beneath steepening mid-level lapse rates. 50 to 60 knots of mid-level flow will overspread this unstable warm sector during the afternoon Tuesday. As this occurs, an uncapped boundary layer and synoptic scale ascent should combine for scattered severe storm development. Wherever moderate to strong instability develops, most likely south of the TN/KY border, supercells are anticipated with a primary threat for large hail. By later in the evening, storms may congeal into a MCS with an increasing damaging wind threat. ...Day 5/Wednesday... A cold front will advance across the Appalachians on Tuesday night/Wednesday morning. Moderate instability is forecast ahead of this cold front Wednesday morning/early afternoon. A few strong to severe storms may develop along the front before it moves into the Atlantic. However, the limited duration of this threat, and potential for timing shifts as newer guidance arrives, precludes severe weather probabilities at this time. ...Day6-8.. A relatively benign severe weather pattern is expected from Thursday/Day 6 into next weekend as a cold front pushes into the Gulf. A few storms are possible along the cold front as it moves south along the Florida Peninsula on Thursday. Otherwise, more robust moisture recovery will begin Thursday night. Overall, moisture quality will be low initially, but eventually some threat may develop across the Plains as low-level moisture advection continues. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0340 AM CDT Sat May 17 2025 Valid 201200Z - 251200Z ...DISCUSSION... ...Day 4/Tuesday... As the primary mid-level trough shifts east on Tuesday, scattered severe thunderstorms are likely across parts of the Mid-Mississippi Valley into the Tennessee Valley. Upper 60s to low 70s dewpoints will be present ahead of a cold front. Convection/cloud cover from Day 3 convection across the Plains/Ozarks will impact destabilization across Kentucky and into the Ohio Valley. However, farther south, strong destabilization is likely as the boundary layer heats beneath steepening mid-level lapse rates. 50 to 60 knots of mid-level flow will overspread this unstable warm sector during the afternoon Tuesday. As this occurs, an uncapped boundary layer and synoptic scale ascent should combine for scattered severe storm development. Wherever moderate to strong instability develops, most likely south of the TN/KY border, supercells are anticipated with a primary threat for large hail. By later in the evening, storms may congeal into a MCS with an increasing damaging wind threat. ...Day 5/Wednesday... A cold front will advance across the Appalachians on Tuesday night/Wednesday morning. Moderate instability is forecast ahead of this cold front Wednesday morning/early afternoon. A few strong to severe storms may develop along the front before it moves into the Atlantic. However, the limited duration of this threat, and potential for timing shifts as newer guidance arrives, precludes severe weather probabilities at this time. ...Day6-8.. A relatively benign severe weather pattern is expected from Thursday/Day 6 into next weekend as a cold front pushes into the Gulf. A few storms are possible along the cold front as it moves south along the Florida Peninsula on Thursday. Otherwise, more robust moisture recovery will begin Thursday night. Overall, moisture quality will be low initially, but eventually some threat may develop across the Plains as low-level moisture advection continues. Read more