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SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1243 AM CDT Fri Jul 12 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE NORTHERN AND CENTRAL GREAT PLAINS... ...SUMMARY... Isolated severe wind and hail will be possible over the northern and central Great Plains from late afternoon into tonight. ...Northern/central Great Plains... Hot temperatures from the upper 90s to 105 will be prevalent near a surface trough extending from the MT/ND border area to eastern CO. Rich boundary-layer moisture will be displaced farther east across the central to eastern Dakotas to the Lower MO Valley, beneath an elevated mixed layer and modest capping. Scattered high-based thunderstorms will most likely develop during the late afternoon to early evening, within the uncapped and deeply mixed environment along the surface trough. In the mid-levels, the region will lie within a modest northwesterly flow regime between a stout anticyclone over the southern Great Basin and a low-amplitude shortwave trough in the eastern Great Lakes. This flow orientation should result in outflow-dominated cells/clusters impinging on greater buoyancy downstream. This may sustain a severe wind threat past sunset into the lower plains. In addition, a modest low-level warm advection regime tonight within a conditionally favorable supercell environment could support a threat for large hail, similar to what occurred on Thursday evening in the Kansas City Metro vicinity. Spatial confidence is low given the expected weak large-scale forcing for ascent. Still, have broadened the level 1-MRGL risk eastward to account for both possibilities. ..Grams/Moore.. 07/12/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1243 AM CDT Fri Jul 12 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE NORTHERN AND CENTRAL GREAT PLAINS... ...SUMMARY... Isolated severe wind and hail will be possible over the northern and central Great Plains from late afternoon into tonight. ...Northern/central Great Plains... Hot temperatures from the upper 90s to 105 will be prevalent near a surface trough extending from the MT/ND border area to eastern CO. Rich boundary-layer moisture will be displaced farther east across the central to eastern Dakotas to the Lower MO Valley, beneath an elevated mixed layer and modest capping. Scattered high-based thunderstorms will most likely develop during the late afternoon to early evening, within the uncapped and deeply mixed environment along the surface trough. In the mid-levels, the region will lie within a modest northwesterly flow regime between a stout anticyclone over the southern Great Basin and a low-amplitude shortwave trough in the eastern Great Lakes. This flow orientation should result in outflow-dominated cells/clusters impinging on greater buoyancy downstream. This may sustain a severe wind threat past sunset into the lower plains. In addition, a modest low-level warm advection regime tonight within a conditionally favorable supercell environment could support a threat for large hail, similar to what occurred on Thursday evening in the Kansas City Metro vicinity. Spatial confidence is low given the expected weak large-scale forcing for ascent. Still, have broadened the level 1-MRGL risk eastward to account for both possibilities. ..Grams/Moore.. 07/12/2024 Read more

834
ABPZ20 KNHC 120503
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM PDT Thu Jul 11 2024

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

Central East Pacific:
A tropical wave over the far eastern Pacific is producing
disorganized showers and a few thunderstorms. The wave is forecast
to move westward or west-northwestward at 15 mph during the next
few days, and conditions could become conducive for some slow
development next week while the wave moves through the central
portion of the basin.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...20 percent.

$$
Forecaster Berg

South Carolina’s Department of Natural Resources says all of the state’s 46 counties are facing some degree of drought this summer. While some Lowcountry counties are in “severe” drought, others are showing only the early stages of drought. Farmers in Williamsburg County like Oneal Bluefort say it will affect their crops and this drought impacts their crops. “Being that we got the severe drought right now, it’s kind of locked up the plant. And it’s gonna have a slow response in everything you feed it. And we feed it in the rain, unfortunately. We don’t have irrigation,” Bluefort said. Bluefort has been farming since he was seven years old, so he has learned what makes for a good year of harvest. The state’s Drought Response Committee broke down conditions county-by-county. In the Lowcountry, Williamsburg and Georgetown Counties are experiencing a “severe” drought. Other Lowcountry counties including Colleton, Dorchester and Orangeburg Counties are seeing “moderate” drought levels. Charleston, Berkeley and Beaufort counties are in the incipient or beginning stages of a drought. Bluefort says he knows without rainfall, there is nothing they can do. “One thing I learned about being a farmer, is you’re gonna have to adapt. You’re gonna have to hold on, keep looking up. It’ll change. You get your good years, you get your bad years, but that’s what makes a farmer,” Bluefort said. Another farmer said the corn can’t be saved. He described the corn as “pitiful,” because the corn was either covered in fungus, rotten or unable to produce the seeds. They said this lack of rain could impact the supply and demand. “The corn you know feeds hogs and chickens and will probably make the food prices go up because no corn to feed all the animals and the animals got to eat, and the people will eat the animals…it’s a bad year,” a farmer said. Bluefort said he knows this a bad year, and it will be hard to come back from, but all you can do is hope. WCSC Live 5 News (Charleston, SC), 7/12/24.

MD 1582 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR NORTHEAST KANSAS TO NORTHWEST MISSOURI
Mesoscale Discussion 1582 NWS Storm Prediction Center Norman OK 1036 PM CDT Thu Jul 11 2024 Areas affected...Northeast Kansas to northwest Missouri Concerning...Severe potential...Watch unlikely Valid 120336Z - 120500Z Probability of Watch Issuance...5 percent SUMMARY...An isolated severe hail risk may persist across northwest Missouri into northeast Kansas for the next 1-2 hours; however, long-term trends should favor destructive storm interactions and an overall weakening trend. Watch issuance is not expected. DISCUSSION...Ongoing thunderstorms across the broader Kansas City region have had a history of producing severe hail (up to 1.75 inches) over roughly the past hour. While individual storm longevity has been fairly limited, deep convection continues to develop along the south/southwestern flank of the convective outflow. Additionally, new convective towers are noted to the northwest into northeast KS as a weak mid-level perturbation pivots into the region. Modest deep-layer shear (around 25-30 knots) is expected to continue to limit storm longevity/organization, and storm motions/propagation to the south/southeast along the developing initiation axis should favor upscale growth and destructive storm interactions with time. However, prior to upscale growth more discrete, intense updraft pulses may realize the moderately unstable air mass (2000-2500 J/kg MLCAPE based on the 00Z TOP sounding and recent RAP mesoanalysis estimates) and continue to support a sporadic severe hail threat within a narrow corridor from northeast KS to northwest MO. ..Moore/Gleason.. 07/12/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...EAX...OAX...TOP... LAT...LON 38449413 38919508 39259583 39569630 39819638 39989629 40089607 40059552 39779476 39439407 39179378 38939364 38729361 38569363 38489369 38429379 38409386 38449413 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0745 PM CDT Thu Jul 11 2024 Valid 120100Z - 121200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN PARTS OF SOUTH AZ AND SOUTHEAST KS/SOUTHWEST MO... ...SUMMARY... Sporadic severe gusts are possible over southern Arizona through about dusk. Isolated large hail and locally damaging winds are possible over southeast Kansas and southwest Missouri this evening. ...Southern AZ... With surface temperature-dew point spreads around 60 F, multiple convective outflows have been surging west and south across the I-10/19 corridors in southeast AZ. Weak deep-layer shear remains noted in EMX VWP data and further confirmed by the 00Z TUS sounding with mid-level flow holding from 15-20 kts. This has yielded a more disorganized and variable outflow direction, although some loose clustering appears to have occurred in the greater Tucson vicinity. This activity should spread southwest into the south-central AZ border area during the next couple hours with a continued risk for sporadic severe gusts. ...Southeast KS and southwest MO... Along a weak, quasi-stationary front, isolated thunderstorms are ongoing over southeast KS into southwest MO. A vertically veering wind profile, supported by low-level southerlies beneath modest mid-level northwesterlies, will sustain occasional updraft rotation with slow-moving discrete cells. With MLCAPE near 2500 J/kg, as sampled by the 00Z TOP sounding, isolated large hail and locally strong gusts will remain possible. A slight increase in low-level flow this evening may yield convection persisting after dusk, although tending to become elevated and develop northeast of the surface front with time. The overall severe threat should wane overnight. ...Central High Plains to northern Great Plains... High-based, lower-topped convection has struggled on the western periphery of the Great Plains buoyancy plume amid moderate mid/upper-level northwest flow. While a localized strong to marginally severe wind gust may be possible over the next hour or so, the unconditional probability of occurrence appears less than 5 percent. ..Grams.. 07/12/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0745 PM CDT Thu Jul 11 2024 Valid 120100Z - 121200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN PARTS OF SOUTH AZ AND SOUTHEAST KS/SOUTHWEST MO... ...SUMMARY... Sporadic severe gusts are possible over southern Arizona through about dusk. Isolated large hail and locally damaging winds are possible over southeast Kansas and southwest Missouri this evening. ...Southern AZ... With surface temperature-dew point spreads around 60 F, multiple convective outflows have been surging west and south across the I-10/19 corridors in southeast AZ. Weak deep-layer shear remains noted in EMX VWP data and further confirmed by the 00Z TUS sounding with mid-level flow holding from 15-20 kts. This has yielded a more disorganized and variable outflow direction, although some loose clustering appears to have occurred in the greater Tucson vicinity. This activity should spread southwest into the south-central AZ border area during the next couple hours with a continued risk for sporadic severe gusts. ...Southeast KS and southwest MO... Along a weak, quasi-stationary front, isolated thunderstorms are ongoing over southeast KS into southwest MO. A vertically veering wind profile, supported by low-level southerlies beneath modest mid-level northwesterlies, will sustain occasional updraft rotation with slow-moving discrete cells. With MLCAPE near 2500 J/kg, as sampled by the 00Z TOP sounding, isolated large hail and locally strong gusts will remain possible. A slight increase in low-level flow this evening may yield convection persisting after dusk, although tending to become elevated and develop northeast of the surface front with time. The overall severe threat should wane overnight. ...Central High Plains to northern Great Plains... High-based, lower-topped convection has struggled on the western periphery of the Great Plains buoyancy plume amid moderate mid/upper-level northwest flow. While a localized strong to marginally severe wind gust may be possible over the next hour or so, the unconditional probability of occurrence appears less than 5 percent. ..Grams.. 07/12/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0745 PM CDT Thu Jul 11 2024 Valid 120100Z - 121200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN PARTS OF SOUTH AZ AND SOUTHEAST KS/SOUTHWEST MO... ...SUMMARY... Sporadic severe gusts are possible over southern Arizona through about dusk. Isolated large hail and locally damaging winds are possible over southeast Kansas and southwest Missouri this evening. ...Southern AZ... With surface temperature-dew point spreads around 60 F, multiple convective outflows have been surging west and south across the I-10/19 corridors in southeast AZ. Weak deep-layer shear remains noted in EMX VWP data and further confirmed by the 00Z TUS sounding with mid-level flow holding from 15-20 kts. This has yielded a more disorganized and variable outflow direction, although some loose clustering appears to have occurred in the greater Tucson vicinity. This activity should spread southwest into the south-central AZ border area during the next couple hours with a continued risk for sporadic severe gusts. ...Southeast KS and southwest MO... Along a weak, quasi-stationary front, isolated thunderstorms are ongoing over southeast KS into southwest MO. A vertically veering wind profile, supported by low-level southerlies beneath modest mid-level northwesterlies, will sustain occasional updraft rotation with slow-moving discrete cells. With MLCAPE near 2500 J/kg, as sampled by the 00Z TOP sounding, isolated large hail and locally strong gusts will remain possible. A slight increase in low-level flow this evening may yield convection persisting after dusk, although tending to become elevated and develop northeast of the surface front with time. The overall severe threat should wane overnight. ...Central High Plains to northern Great Plains... High-based, lower-topped convection has struggled on the western periphery of the Great Plains buoyancy plume amid moderate mid/upper-level northwest flow. While a localized strong to marginally severe wind gust may be possible over the next hour or so, the unconditional probability of occurrence appears less than 5 percent. ..Grams.. 07/12/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0745 PM CDT Thu Jul 11 2024 Valid 120100Z - 121200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN PARTS OF SOUTH AZ AND SOUTHEAST KS/SOUTHWEST MO... ...SUMMARY... Sporadic severe gusts are possible over southern Arizona through about dusk. Isolated large hail and locally damaging winds are possible over southeast Kansas and southwest Missouri this evening. ...Southern AZ... With surface temperature-dew point spreads around 60 F, multiple convective outflows have been surging west and south across the I-10/19 corridors in southeast AZ. Weak deep-layer shear remains noted in EMX VWP data and further confirmed by the 00Z TUS sounding with mid-level flow holding from 15-20 kts. This has yielded a more disorganized and variable outflow direction, although some loose clustering appears to have occurred in the greater Tucson vicinity. This activity should spread southwest into the south-central AZ border area during the next couple hours with a continued risk for sporadic severe gusts. ...Southeast KS and southwest MO... Along a weak, quasi-stationary front, isolated thunderstorms are ongoing over southeast KS into southwest MO. A vertically veering wind profile, supported by low-level southerlies beneath modest mid-level northwesterlies, will sustain occasional updraft rotation with slow-moving discrete cells. With MLCAPE near 2500 J/kg, as sampled by the 00Z TOP sounding, isolated large hail and locally strong gusts will remain possible. A slight increase in low-level flow this evening may yield convection persisting after dusk, although tending to become elevated and develop northeast of the surface front with time. The overall severe threat should wane overnight. ...Central High Plains to northern Great Plains... High-based, lower-topped convection has struggled on the western periphery of the Great Plains buoyancy plume amid moderate mid/upper-level northwest flow. While a localized strong to marginally severe wind gust may be possible over the next hour or so, the unconditional probability of occurrence appears less than 5 percent. ..Grams.. 07/12/2024 Read more

169
ABPZ20 KNHC 112331
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 PM PDT Thu Jul 11 2024

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

Central East Pacific:
A tropical wave producing disorganized showers and thunderstorms is
located over Central America. The system is forecast to move
westward at 10 to 15 mph across the tropical East Pacific during the
next few days. Conditions could become favorable for some slow
development of the wave next week as it approaches the central
portion of the basin.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...20 percent.

$$
Forecaster Bucci

No watches are valid as of Thu Jul 11 22:46:01 UTC 2024.

MD 1581 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF THE CENTRAL HIGH PLAINS
Mesoscale Discussion 1581 NWS Storm Prediction Center Norman OK 0522 PM CDT Thu Jul 11 2024 Areas affected...Portions of the central High Plains Concerning...Severe potential...Watch unlikely Valid 112222Z - 120015Z Probability of Watch Issuance...5 percent SUMMARY...Isolated to scattered thunderstorms developing across the central High Plains may pose an isolated severe wind and hail risk through the early evening hours. This threat should remain fairly localized/limited; watch issuance is not expected. DISCUSSION...Over the past 1-2 hours, isolated to scattered high-based thunderstorms have developing along and west of a lee surface trough within a deeply mixed, but marginally buoyant air mass. More recently, thunderstorm longevity has been relatively short lived (around 30-60 minutes) based on radar and GOES IR/cloud-top temperature trends. This is attributable to somewhat meager buoyancy profiles on the periphery of deeper/higher-quality moisture to the east across the Plains. Dewpoint depressions near 40 F and low-level lapse rates near 9 C/km also suggest a very deeply mixed boundary layer is in place, which will favor rapid undercutting outflows given poor low-level storm-relative winds. Thunderstorm coverage may remain limited to near/along the surface trough axis given increasing MLCIN with eastward extent and south/southeasterly storm motions. A few more organized cells are possible given 30-40 knots of effective bulk shear, but the general expectation for the next few hours is for isolated to scattered thunderstorms to primarily pose a severe wind threat given the favorable low-level thermodynamics for strong convective outflow. ..Moore/Gleason.. 07/11/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LBF...DDC...UNR...GLD...PUB...BOU...CYS...BYZ... LAT...LON 37920263 38090307 38490354 38960412 43660535 44140529 44820530 45230503 45500459 45500409 45320356 44820302 44370266 43890242 42130195 40310130 39800117 38880131 38330150 38000172 37910218 37920263 Read more

MD 1580 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTHEASTERN KANSAS INTO SOUTHWEST MISSOURI
Mesoscale Discussion 1580 NWS Storm Prediction Center Norman OK 0344 PM CDT Thu Jul 11 2024 Areas affected...Southeastern Kansas into southwest Missouri Concerning...Severe potential...Watch unlikely Valid 112044Z - 112245Z Probability of Watch Issuance...20 percent SUMMARY...Isolated large hail and severe gusts will be the primary threats with storms that can develop along an outflow boundary. A watch is not anticipated this afternoon. DISCUSSION...Convection from last evening into this morning left an outflow boundary across parts of southeast Kansas into southwest Missouri. A subtle surface low is also evident just east of Pratt, KS in surface observations. Convergence along this boundary has promoted modestly deepening cumulus over the last few hours. Of particular note are more agitated cumulus from near Emporia, KS to south of Eureka, KS. Additional towers are developing northwest of Springfield, MO. The exact area of where strong/severe storms will develop is not certain. CAM guidance has generally suggested robust storm initiation will occur by late afternoon; however, with greater low-level moisture near the boundary than forecast in models, this may occur sooner than anticipated. With weak upper-level support, storm coverage should remain isolated. Strong buoyancy (2000+ J/kg MLCAPE), effective shear of 25-30 kts, and steep mid-level lapse rates will promote a risk of large hail and severe wind gusts. With temperature-dewpoint spreads nearing 30 F (primarily in southeast Kansas), some upscale growth could occur with cold pool mergers. A locally greater severe wind threat would be present should that occur. ..Wendt/Guyer.. 07/11/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...SGF...EAX...TSA...TOP...ICT...OUN... LAT...LON 36929718 37979736 38589764 38869774 38939717 38629520 38229363 37729245 37069241 36729284 36589342 36649467 36929718 Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0500 PM CDT Thu Jul 11 2024 Valid 131200Z - 191200Z Beginning D3/Saturday, an upper-level shortwave trough off the California coast is expected to slowly drift northward along the periphery of a ridge centered over the Great Basin. The enhanced southerly flow associated with this feature will bring sufficient moisture northward for dry thunderstorms into Oregon and Idaho on D3/Saturday and D4/Sunday, with some lingering chances for isolated dry thunder persisting into D6/Tuesday. Throughout the period, westerly flow is expected to persist over much of the Northwest, resulting in episodic chances of dry and windy conditions. ...Intermountain West into the Northwest... Isolated dry thunder is expected for much of the Intermountain West into the Northwest starting on D3/Saturday and persisting through D4/Sunday, as northerly transport of moisture around the periphery of the upper-level ridge continues. Dry and breezy conditions are expected to accompany dry thunderstorm chances, particularly for portions of Southern Oregon and the Snake River Plain, as persistent westerly flow aloft results in downslope mixing and drying of the boundary layer. This combination of meteorological conditions overlaps significantly with fuels receptive to ignition and wildfire spread, warranting the addition of 40% probabilities and the expansion of the dry thunder area for both D3 and D4. Additionally, forecast profiles for D3/D4 show deep inverted-v boundary layers, supportive of gusty thunderstorm outflow. Dry and breezy conditions are likely to persist from D3/Saturday into at least D6/Tuesday over portions of the Northwest into the Snake River Plain with persistent westerly flow aloft. However, the upper-winds are modest, and there remains uncertainty in the magnitude of surface winds beyond D4, precluding the addition of any new highlight areas. There appears to be at least a small chance for dry thunder occurrence over Eastern Idaho into Montana on D5/Monday with lingering moisture exiting the region. However, the probability of dry thunderstorm occurrence appeared too localized to introduce highlights at this time. On D7/Wednesday, guidance suggests that an upper-level shortwave trough will approach the coast of the Northwest, which could bring additional thunder chances at the end of the period. However, significant uncertainty in the evolution of this feature remains, precluding the addition of dry thunder highlights at this time. ..Halbert/Weinman.. 07/11/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0500 PM CDT Thu Jul 11 2024 Valid 131200Z - 191200Z Beginning D3/Saturday, an upper-level shortwave trough off the California coast is expected to slowly drift northward along the periphery of a ridge centered over the Great Basin. The enhanced southerly flow associated with this feature will bring sufficient moisture northward for dry thunderstorms into Oregon and Idaho on D3/Saturday and D4/Sunday, with some lingering chances for isolated dry thunder persisting into D6/Tuesday. Throughout the period, westerly flow is expected to persist over much of the Northwest, resulting in episodic chances of dry and windy conditions. ...Intermountain West into the Northwest... Isolated dry thunder is expected for much of the Intermountain West into the Northwest starting on D3/Saturday and persisting through D4/Sunday, as northerly transport of moisture around the periphery of the upper-level ridge continues. Dry and breezy conditions are expected to accompany dry thunderstorm chances, particularly for portions of Southern Oregon and the Snake River Plain, as persistent westerly flow aloft results in downslope mixing and drying of the boundary layer. This combination of meteorological conditions overlaps significantly with fuels receptive to ignition and wildfire spread, warranting the addition of 40% probabilities and the expansion of the dry thunder area for both D3 and D4. Additionally, forecast profiles for D3/D4 show deep inverted-v boundary layers, supportive of gusty thunderstorm outflow. Dry and breezy conditions are likely to persist from D3/Saturday into at least D6/Tuesday over portions of the Northwest into the Snake River Plain with persistent westerly flow aloft. However, the upper-winds are modest, and there remains uncertainty in the magnitude of surface winds beyond D4, precluding the addition of any new highlight areas. There appears to be at least a small chance for dry thunder occurrence over Eastern Idaho into Montana on D5/Monday with lingering moisture exiting the region. However, the probability of dry thunderstorm occurrence appeared too localized to introduce highlights at this time. On D7/Wednesday, guidance suggests that an upper-level shortwave trough will approach the coast of the Northwest, which could bring additional thunder chances at the end of the period. However, significant uncertainty in the evolution of this feature remains, precluding the addition of dry thunder highlights at this time. ..Halbert/Weinman.. 07/11/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0500 PM CDT Thu Jul 11 2024 Valid 131200Z - 191200Z Beginning D3/Saturday, an upper-level shortwave trough off the California coast is expected to slowly drift northward along the periphery of a ridge centered over the Great Basin. The enhanced southerly flow associated with this feature will bring sufficient moisture northward for dry thunderstorms into Oregon and Idaho on D3/Saturday and D4/Sunday, with some lingering chances for isolated dry thunder persisting into D6/Tuesday. Throughout the period, westerly flow is expected to persist over much of the Northwest, resulting in episodic chances of dry and windy conditions. ...Intermountain West into the Northwest... Isolated dry thunder is expected for much of the Intermountain West into the Northwest starting on D3/Saturday and persisting through D4/Sunday, as northerly transport of moisture around the periphery of the upper-level ridge continues. Dry and breezy conditions are expected to accompany dry thunderstorm chances, particularly for portions of Southern Oregon and the Snake River Plain, as persistent westerly flow aloft results in downslope mixing and drying of the boundary layer. This combination of meteorological conditions overlaps significantly with fuels receptive to ignition and wildfire spread, warranting the addition of 40% probabilities and the expansion of the dry thunder area for both D3 and D4. Additionally, forecast profiles for D3/D4 show deep inverted-v boundary layers, supportive of gusty thunderstorm outflow. Dry and breezy conditions are likely to persist from D3/Saturday into at least D6/Tuesday over portions of the Northwest into the Snake River Plain with persistent westerly flow aloft. However, the upper-winds are modest, and there remains uncertainty in the magnitude of surface winds beyond D4, precluding the addition of any new highlight areas. There appears to be at least a small chance for dry thunder occurrence over Eastern Idaho into Montana on D5/Monday with lingering moisture exiting the region. However, the probability of dry thunderstorm occurrence appeared too localized to introduce highlights at this time. On D7/Wednesday, guidance suggests that an upper-level shortwave trough will approach the coast of the Northwest, which could bring additional thunder chances at the end of the period. However, significant uncertainty in the evolution of this feature remains, precluding the addition of dry thunder highlights at this time. ..Halbert/Weinman.. 07/11/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0500 PM CDT Thu Jul 11 2024 Valid 131200Z - 191200Z Beginning D3/Saturday, an upper-level shortwave trough off the California coast is expected to slowly drift northward along the periphery of a ridge centered over the Great Basin. The enhanced southerly flow associated with this feature will bring sufficient moisture northward for dry thunderstorms into Oregon and Idaho on D3/Saturday and D4/Sunday, with some lingering chances for isolated dry thunder persisting into D6/Tuesday. Throughout the period, westerly flow is expected to persist over much of the Northwest, resulting in episodic chances of dry and windy conditions. ...Intermountain West into the Northwest... Isolated dry thunder is expected for much of the Intermountain West into the Northwest starting on D3/Saturday and persisting through D4/Sunday, as northerly transport of moisture around the periphery of the upper-level ridge continues. Dry and breezy conditions are expected to accompany dry thunderstorm chances, particularly for portions of Southern Oregon and the Snake River Plain, as persistent westerly flow aloft results in downslope mixing and drying of the boundary layer. This combination of meteorological conditions overlaps significantly with fuels receptive to ignition and wildfire spread, warranting the addition of 40% probabilities and the expansion of the dry thunder area for both D3 and D4. Additionally, forecast profiles for D3/D4 show deep inverted-v boundary layers, supportive of gusty thunderstorm outflow. Dry and breezy conditions are likely to persist from D3/Saturday into at least D6/Tuesday over portions of the Northwest into the Snake River Plain with persistent westerly flow aloft. However, the upper-winds are modest, and there remains uncertainty in the magnitude of surface winds beyond D4, precluding the addition of any new highlight areas. There appears to be at least a small chance for dry thunder occurrence over Eastern Idaho into Montana on D5/Monday with lingering moisture exiting the region. However, the probability of dry thunderstorm occurrence appeared too localized to introduce highlights at this time. On D7/Wednesday, guidance suggests that an upper-level shortwave trough will approach the coast of the Northwest, which could bring additional thunder chances at the end of the period. However, significant uncertainty in the evolution of this feature remains, precluding the addition of dry thunder highlights at this time. ..Halbert/Weinman.. 07/11/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0500 PM CDT Thu Jul 11 2024 Valid 131200Z - 191200Z Beginning D3/Saturday, an upper-level shortwave trough off the California coast is expected to slowly drift northward along the periphery of a ridge centered over the Great Basin. The enhanced southerly flow associated with this feature will bring sufficient moisture northward for dry thunderstorms into Oregon and Idaho on D3/Saturday and D4/Sunday, with some lingering chances for isolated dry thunder persisting into D6/Tuesday. Throughout the period, westerly flow is expected to persist over much of the Northwest, resulting in episodic chances of dry and windy conditions. ...Intermountain West into the Northwest... Isolated dry thunder is expected for much of the Intermountain West into the Northwest starting on D3/Saturday and persisting through D4/Sunday, as northerly transport of moisture around the periphery of the upper-level ridge continues. Dry and breezy conditions are expected to accompany dry thunderstorm chances, particularly for portions of Southern Oregon and the Snake River Plain, as persistent westerly flow aloft results in downslope mixing and drying of the boundary layer. This combination of meteorological conditions overlaps significantly with fuels receptive to ignition and wildfire spread, warranting the addition of 40% probabilities and the expansion of the dry thunder area for both D3 and D4. Additionally, forecast profiles for D3/D4 show deep inverted-v boundary layers, supportive of gusty thunderstorm outflow. Dry and breezy conditions are likely to persist from D3/Saturday into at least D6/Tuesday over portions of the Northwest into the Snake River Plain with persistent westerly flow aloft. However, the upper-winds are modest, and there remains uncertainty in the magnitude of surface winds beyond D4, precluding the addition of any new highlight areas. There appears to be at least a small chance for dry thunder occurrence over Eastern Idaho into Montana on D5/Monday with lingering moisture exiting the region. However, the probability of dry thunderstorm occurrence appeared too localized to introduce highlights at this time. On D7/Wednesday, guidance suggests that an upper-level shortwave trough will approach the coast of the Northwest, which could bring additional thunder chances at the end of the period. However, significant uncertainty in the evolution of this feature remains, precluding the addition of dry thunder highlights at this time. ..Halbert/Weinman.. 07/11/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 1579 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR SOUTHEASTERN ARIZONA AND ADJACENT SOUTHWESTERN NEW MEXICO
Mesoscale Discussion 1579 NWS Storm Prediction Center Norman OK 0158 PM CDT Thu Jul 11 2024 Areas affected...southeastern Arizona and adjacent southwestern New Mexico Concerning...Severe potential...Watch possible Valid 111858Z - 112200Z Probability of Watch Issuance...40 percent SUMMARY...Thunderstorms developing across the higher terrain may generate strengthening outflow spreading southwestward across lower elevations, toward the central/southeastern Arizona international border area, through 2-4 PM MST. This probably will be accompanied by strong to occasionally severe wind gusts and blowing dust. While it is not clear that this will require a severe weather watch, trends are being monitored. DISCUSSION...While morning soundings indicated some increase in precipitable water across the region over the past 24 hours or so, low-level moisture remains seasonably modest with surface dew points across much of the lower deserts forecast to fall into the mid 40s to near 50 F by peak afternoon heating and boundary-layer mixing. Still, across the higher terrain, including the Mogollon Rim vicinity of eastern central Arizona into southwestern New Mexico, the moisture has been sufficient to support deepening convective development and the initiation of thunderstorm activity. Beneath a belt of northeasterly to easterly mid-level (cloud-bearing layer) flow (initially convectively augmented, but now weakening to around 20-25 kt or so), guidance suggests that additional thunderstorm development is increasingly probable during the next few hours across the higher terrain of southeastern Arizona into Sonora. However, upslope into/across the Mogollon Rim vicinity may support the most prominent clustering and upscale growth of convection. Gradually, aided by increasing precipitation loading and sub-cloud evaporative cooling, strengthening downdrafts appear likely to consolidate into larger-scale scale southward and southwestward propagating outflow, which may be accompanied by increasing potential for strong surface gusts. Given the weak CAPE evident in forecast soundings for the strongly heated and increasingly deeply-mixed boundary layer in lower elevations, the extent of renewed convective development along/above the outflow remains unclear. However, it appears possible that this could be sufficient to support strong to locally severe gusts into the lower deserts and across the international border by early evening. ..Kerr/Guyer.. 07/11/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...EPZ...TWC...PSR... LAT...LON 33511079 33371017 33150957 33060894 32980839 32400803 31300905 30971066 31581194 32091125 33251122 33511079 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0257 PM CDT Thu Jul 11 2024 Valid 112000Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF SOUTHERN ARIZONA... ...SUMMARY... Severe thunderstorm wind gusts are possible over parts of southern Arizona from mid-afternoon through early/mid-evening. Little change was necessary for the 20Z update. The primary of severe risk continues to be over parts of southern AZ, downstream of storms now developing along the Rim. The air mass is destabilizing with heating with 500-1000 J/kg MUCAPE currently. Modest northeast winds in the midlevels and the unstable surface air mass should foster west/southwestward propagation later today, with strong to locally severe gusts possible. For more information see mesoscale discussion 1579. ..Jewell.. 07/11/2024 .PREV DISCUSSION... /ISSUED 1145 AM CDT Thu Jul 11 2024/ ...Arizona... Widely scattered to scattered thunderstorms are expected to develop this afternoon over the Mogollon Rim, and smaller mountain ranges to the south. That will occur as strong insolation at those higher elevations preferentially removes MLCINH, in the presence of generally greater low-level moisture than previous days. Some strengthening of flow aloft is expected over this region on the southeast periphery of the upper anticyclone. This will support convective motion off the Rim (and small mountain ranges to its south), into strongly heated/deeply mixed boundary layers of the desert floor. Isolated strong-severe gusts are possible from the relatively early, more-discrete activity, and swaths of strong-severe gusts are possible as convection moves southwestward toward the international border. ...Northern High Plains... Isolated to widely scattered, high-based thunderstorms are expected to form near the lee trough, where both relatively maximized convergence and strong surface heating should contribute to enough lift for convective initiation. The main concern should be damaging to severe gusts, given the deeply mixed subcloud layer. Isolated severe hail also may occur, amidst enough deep-layer shear for some organized thunderstorms (effective-shear magnitudes of 30-40 kt). Lack of greater moisture and buoyancy will be a limiting factor for coverage and intensity of convection, which should diminish rapidly after sunset. ...Southeast Kansas/Southern Missouri... A few severe storms could develop today to the east-northeast of a surface wave near the Oklahoma/Kansas border in vicinity of front that extends into Missouri, which may be somewhat effectively augmented by lingering early day convection. Moderate to locally strong buoyancy will exist within a moist environment, with MLCAPE likely to reach 2500-3000 J/kg. A considerable vertical veering of winds will exist through the lower/middle troposphere, with around 30 kt effective shear. Instances of severe hail and/or wind gusts could occur. ...Southern Maine... Clouds have lingered much of the morning with rather weak lapse rates noted in the 12z KGYX/Gray Maine observed sounding, but clearing is occurring from the west and a narrow zone of modest destabilization should occur this afternoon, within a very moist environment (lower/middle 70s F surface dewpoints) ahead of a cold front. Pending sufficient destabilization, a locally severe storm or two could occur, potentially with an absence of lightning, in the presence of long/semi-straight hodographs (highlighted by 45-50 kt winds 3-6 km AGL). ...Central/south-central portions of Illinois and Indiana... Ample low-level CAPE (100+ J/kg 0-km AGL) near the southward-shifting boundary could lead to some potential for funnels or perhaps even a brief non-supercell tornado this afternoon. Some of the storms could otherwise pose a risk for gusty winds, but the overall potential for organized severe storms is currently expected to remain low. Read more