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SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0244 PM CDT Sat Jul 13 2024 Valid 132000Z - 141200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN HIGH PLAINS... ...SUMMARY... Multiple clusters of strong to severe thunderstorms are possible across portions of the Northern Plains into the Upper Mississippi Valley through tonight. Other more isolated strong storms are possible in northern New England, and portions of Nevada. ...20z Update... The previous outlook remains on track, and no changes are needed with the 20z update. For short term information on severe potential across portions of NV/AZ/UT, as well as across the northern High Plains, see MCDs 1593 and 1594. Otherwise, see previous discussion below for more forecast details. ..Leitman.. 07/13/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Sat Jul 13 2024/ ...Northern High Plains... Relatively fast westerly mid-level flow is present today across the northern Rockies/Plains. Several weak shortwave troughs are tracking across southern Canada and parts of MT/ND today, including one with an associated cluster of thunderstorms over southwest SK. Persistent east-southeasterly low level winds ahead of this system across eastern MT will likely allow it to persist through the day and intensify with afternoon heating. A combination of supercells and bowing structures are suggested by morning CAM guidance, with a risk of large hail and damaging winds tracking across northeast MT into western ND during the late afternoon and evening. Given the consistent signal in guidance for fast-moving storms, and the favorable CAPE/shear environment, have upgraded parts of this corridor to ENH risk. ...MN/WI and Vicinity... Remnant MCS and associated MCV is currently located over southeast MN. This system will track southeastward across central/southern WI through the afternoon, where strong daytime heating and dewpoints in the upper 60s to lower 70s will yield strong instability. Re-development of storms is possible, with a few severe/supercell storms possible - capable of hail and damaging wind gusts. Later this evening, thunderstorms are expected to intensify along a weak cold front sagging into northeast ND and northern MN. These storms are depicted by most morning CAM solutions to organize into a linear MCS and spread southeastward across much of MN and northern WI overnight. This scenario would pose a risk of damaging winds and some hail in this area as well. ...Northern New England... Scattered thunderstorms have begun to form this afternoon across southern Quebec and parts of northern VT/NH/ME. Relatively strong westerly flow aloft and moderate CAPE values will promote a risk of locally gusty/damaging winds in the stronger cells through the afternoon. ...NV and Vicinity... Similar to the last couple of days, ample mid-level moisture is present today across parts of NV, western UT, and northwest AZ. Hot surface conditions and steep mid-level lapse rates will yield widespread inverted-v profiles. Model guidance suggests scattered coverage of high-based thunderstorms, with sufficient winds aloft to promote locally damaging wind gusts in the stronger downdrafts. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0244 PM CDT Sat Jul 13 2024 Valid 132000Z - 141200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN HIGH PLAINS... ...SUMMARY... Multiple clusters of strong to severe thunderstorms are possible across portions of the Northern Plains into the Upper Mississippi Valley through tonight. Other more isolated strong storms are possible in northern New England, and portions of Nevada. ...20z Update... The previous outlook remains on track, and no changes are needed with the 20z update. For short term information on severe potential across portions of NV/AZ/UT, as well as across the northern High Plains, see MCDs 1593 and 1594. Otherwise, see previous discussion below for more forecast details. ..Leitman.. 07/13/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Sat Jul 13 2024/ ...Northern High Plains... Relatively fast westerly mid-level flow is present today across the northern Rockies/Plains. Several weak shortwave troughs are tracking across southern Canada and parts of MT/ND today, including one with an associated cluster of thunderstorms over southwest SK. Persistent east-southeasterly low level winds ahead of this system across eastern MT will likely allow it to persist through the day and intensify with afternoon heating. A combination of supercells and bowing structures are suggested by morning CAM guidance, with a risk of large hail and damaging winds tracking across northeast MT into western ND during the late afternoon and evening. Given the consistent signal in guidance for fast-moving storms, and the favorable CAPE/shear environment, have upgraded parts of this corridor to ENH risk. ...MN/WI and Vicinity... Remnant MCS and associated MCV is currently located over southeast MN. This system will track southeastward across central/southern WI through the afternoon, where strong daytime heating and dewpoints in the upper 60s to lower 70s will yield strong instability. Re-development of storms is possible, with a few severe/supercell storms possible - capable of hail and damaging wind gusts. Later this evening, thunderstorms are expected to intensify along a weak cold front sagging into northeast ND and northern MN. These storms are depicted by most morning CAM solutions to organize into a linear MCS and spread southeastward across much of MN and northern WI overnight. This scenario would pose a risk of damaging winds and some hail in this area as well. ...Northern New England... Scattered thunderstorms have begun to form this afternoon across southern Quebec and parts of northern VT/NH/ME. Relatively strong westerly flow aloft and moderate CAPE values will promote a risk of locally gusty/damaging winds in the stronger cells through the afternoon. ...NV and Vicinity... Similar to the last couple of days, ample mid-level moisture is present today across parts of NV, western UT, and northwest AZ. Hot surface conditions and steep mid-level lapse rates will yield widespread inverted-v profiles. Model guidance suggests scattered coverage of high-based thunderstorms, with sufficient winds aloft to promote locally damaging wind gusts in the stronger downdrafts. Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Sat Jul 13 2024 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS INTO WESTERN MINNESOTA... ...SUMMARY... Strong to severe thunderstorms are possible from the northern Plains into the Upper Midwest on Sunday. ...Synopsis... An upper shortwave trough over the upper Great Lakes is forecast to develop east toward NY/southern New England Sunday into early Monday. Meanwhile, an upper anticyclone is forecast to persist over the Four Corners and southern Rockies vicinity, with a subtropical high extending into the Southeast. A belt of enhanced northwesterly upper level flow will stretch from MT into the northern Plains/Upper Midwest vicinity. Several shortwave impulses are forecast to migrate through this area of northwesterly flow through the period. Some more appreciable height falls are possible Sunday night/early Monday as a compact upper shortwave trough migrates across the Canadian Prairies toward ND and the Upper Midwest. This area of northwesterly flow aloft and the aforementioned shortwaves will focus severe thunderstorm potential on Sunday across portions of the northern Plains to the Great Lakes vicinity. ...Southern WI/Northern IL into southern Lower MI/northern OH... A seasonally moist airmass will be in place on Sunday with dewpoints in the upper 60s to low 70s. This will support moderate to strong destabilization across the Marginal (level 1 of 5) risk area. Most guidance indicates remnant convection and convectively enhanced vorticity maxima will be ongoing/located in the vicinity of southern Lake Michigan during the morning, and shift east through the period. This MCV will enhance otherwise modest vertical shear, and focus thunderstorm development through the afternoon and evening. Thunderstorm clusters will mainly pose a risk for severe/damaging gusts, though isolated hail also will be possible. Higher severe probabilities may be needed in subsequent outlooks if confidence increases in a corridor of greater storm organization. ...Northern Plains vicinity... Several surface boundaries will focus thunderstorm development across the region during the afternoon and into the overnight as the upper shortwave trough develops east/southeast toward the international border. One boundary will be draped across northern WI/MN into northwest ND. Meanwhile, a surface trough will extend southward across western ND/SD/NE before a synoptic cold front dives south/southeast across northern High Plains late in the period. Within the warm sector wedge between these boundaries, a seasonally moist and very unstable airmass will be in place. Enhanced northwesterly flow aloft amid vertically veering low-level wind profiles will result in moderate to strong vertical shear supporting supercells and organized line segments should upscale development occur. Isolated convection will likely develop during the late afternoon in the vicinity of the surface trough across the High Plains. High-based supercells capable of large hail and strong outflow gusts are expected with this initial activity. As stronger height falls occur during the evening, a modest southwesterly low-level jet and large-scale ascent will increase. More widespread thunderstorm development is expected as this occurs, and one or more lines/bowing segments may develop east/southeast across the region. While some boundary-layer stabilization occurs nocturnally, strong instability and potentially well-organized convection should be sufficient for a severe/damaging gust risk to persist into the eastern Dakotas and western MN into the nighttime hours. ..Leitman.. 07/13/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Sat Jul 13 2024 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS INTO WESTERN MINNESOTA... ...SUMMARY... Strong to severe thunderstorms are possible from the northern Plains into the Upper Midwest on Sunday. ...Synopsis... An upper shortwave trough over the upper Great Lakes is forecast to develop east toward NY/southern New England Sunday into early Monday. Meanwhile, an upper anticyclone is forecast to persist over the Four Corners and southern Rockies vicinity, with a subtropical high extending into the Southeast. A belt of enhanced northwesterly upper level flow will stretch from MT into the northern Plains/Upper Midwest vicinity. Several shortwave impulses are forecast to migrate through this area of northwesterly flow through the period. Some more appreciable height falls are possible Sunday night/early Monday as a compact upper shortwave trough migrates across the Canadian Prairies toward ND and the Upper Midwest. This area of northwesterly flow aloft and the aforementioned shortwaves will focus severe thunderstorm potential on Sunday across portions of the northern Plains to the Great Lakes vicinity. ...Southern WI/Northern IL into southern Lower MI/northern OH... A seasonally moist airmass will be in place on Sunday with dewpoints in the upper 60s to low 70s. This will support moderate to strong destabilization across the Marginal (level 1 of 5) risk area. Most guidance indicates remnant convection and convectively enhanced vorticity maxima will be ongoing/located in the vicinity of southern Lake Michigan during the morning, and shift east through the period. This MCV will enhance otherwise modest vertical shear, and focus thunderstorm development through the afternoon and evening. Thunderstorm clusters will mainly pose a risk for severe/damaging gusts, though isolated hail also will be possible. Higher severe probabilities may be needed in subsequent outlooks if confidence increases in a corridor of greater storm organization. ...Northern Plains vicinity... Several surface boundaries will focus thunderstorm development across the region during the afternoon and into the overnight as the upper shortwave trough develops east/southeast toward the international border. One boundary will be draped across northern WI/MN into northwest ND. Meanwhile, a surface trough will extend southward across western ND/SD/NE before a synoptic cold front dives south/southeast across northern High Plains late in the period. Within the warm sector wedge between these boundaries, a seasonally moist and very unstable airmass will be in place. Enhanced northwesterly flow aloft amid vertically veering low-level wind profiles will result in moderate to strong vertical shear supporting supercells and organized line segments should upscale development occur. Isolated convection will likely develop during the late afternoon in the vicinity of the surface trough across the High Plains. High-based supercells capable of large hail and strong outflow gusts are expected with this initial activity. As stronger height falls occur during the evening, a modest southwesterly low-level jet and large-scale ascent will increase. More widespread thunderstorm development is expected as this occurs, and one or more lines/bowing segments may develop east/southeast across the region. While some boundary-layer stabilization occurs nocturnally, strong instability and potentially well-organized convection should be sufficient for a severe/damaging gust risk to persist into the eastern Dakotas and western MN into the nighttime hours. ..Leitman.. 07/13/2024 Read more

000
ABPZ20 KNHC 131721
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Sat Jul 13 2024

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

Central and Western East Pacific:
A pair of tropical waves located south and southwest of the coast of
Mexico are producing areas of disorganized shower and thunderstorm
activity. These waves are likely to merge in a few days.
Subsequent development, if any, should be slow to occur while the
combined system moves west-northwestward across the central and
western portion of the basin next week.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...10 percent.

$$
Forecaster Beven

Goats on a farm in Bridgewater were not producing as much milk due to the drought and heat. The goats were being fed more hay. Hay was in higher demand amid the drought and poor grass growth, so it’s more expensive. WHSV (Harrisonburg, Va.), July 12, 2024

Dryland corn was suffering from the lack of rain in South Carolina. Corn in the Lowcountry was reported to be mostly burned up, according to the most recent USDA NASS Crop Progress report, and the Pee Dee region was experiencing early tasseling. Soybean planting was delayed, and conditions have worsened for livestock. SFN Today (Raleigh, N.C.), July 9, 2024

No watches are valid as of Fri Jul 12 21:47:01 UTC 2024.

MD 1584 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR FAR NORTHEASTERN MONTANA...WESTERN NORTH DAKOTA...AND FAR NORTHWESTERN SOUTH DAKOTA
Mesoscale Discussion 1584 NWS Storm Prediction Center Norman OK 0356 PM CDT Fri Jul 12 2024 Areas affected...Far northeastern Montana...western North Dakota...and far northwestern South Dakota Concerning...Severe potential...Watch unlikely Valid 122056Z - 122300Z Probability of Watch Issuance...20 percent SUMMARY...Widely scattered thunderstorms are expected to develop over the next 1-2 hours across portions of western ND, far northeastern MT, and far northwestern SD. Severe wind gusts near 65-76 mph, hail up to 1.5-2.0" in diameter, and perhaps a landspout tornado or two will be possible with the stronger thunderstorms. DISCUSSION...Diurnal heating across the northern plains has resulted in very warm temperatures in the low to upper 90s developing this afternoon. This, combined with surface dewpoints in the low 70s east of a surface trough/quasi-stationary warm front below steep mid-level lapse rates, is yielding 1500-3000 J/kg of MLCAPE. Recent satellite imagery shows increasing cumulus beginning to develop along the aforementioned trough. In addition, convective initiation has already taken place near Manning, ND. Increasing mid-level flow throughout late this afternoon into early this evening will likely support some thunderstorm organization and the potential for a few supercells. Thunderstorm coverage is expected to slowly increase late this afternoon, as destabilization continues under cooler temperatures aloft, subtle DCVA impacts the area, and surface convergence is enhanced. Considering large dewpoint-temperature spreads further west near the MT/ND border, damaging wind gusts appear more likely there, although a few instances of large hail cannot be ruled out through early this evening. Increasing low level helicity via backed surface flow with time, along with some enhanced stretching, could also support a landspout or two before sunset. Although a watch does not appear likely at this time due to an uncertainty in severe thunderstorm coverage, convective trends will be monitored closely over the next 1-2 hours. ..Barnes/Hart.. 07/12/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ABR...BIS...UNR...BYZ...GGW... LAT...LON 46920434 47680556 48480593 48910571 49010481 48990386 48920285 48320199 47280116 46220052 45280096 44920207 45570383 46920434 Read more

MD 1585 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR FAR NORTHEAST ARKANSAS INTO SOUTHERN ILLINOIS AND FAR SOUTHWEST INDIANA
Mesoscale Discussion 1585 NWS Storm Prediction Center Norman OK 0440 PM CDT Fri Jul 12 2024 Areas affected...Far northeast Arkansas into southern Illinois and far southwest Indiana Concerning...Severe potential...Watch unlikely Valid 122140Z - 122315Z Probability of Watch Issuance...5 percent SUMMARY...A localized threat for isolated hail and damaging winds may continue for the next 1-2 hours across far northeast Arkansas into southern Illinois and far southwest Indiana. In general, the severe threat is expected to wane heading into the evening hours. DISCUSSION...Regional radar composites and GOES visible imagery show a clear convective cold pool expanding across the lower OH River Valley region with convection largely struggling to remain sustained (largely owing to weak environmental shear and storm motions into the cold pool). However, over the past 30 minutes, a couple of brief, but relatively intense updrafts have been noted in IR cloud-top temperatures. MRMS hail metrics suggest hail may be approaching severe limits, and the overall thermodynamic environment on the periphery of the cold pool (characterized by over 2000 J/kg MLCAPE and somewhat steep lapse rates in the lowest 1-2 km) may support damaging downburst winds. Ambient lift along the outflow boundary and ahead of a weak MCV over southeast MO may support additional convection over the next 1-2 hours, but storm longevity (and the overall severe threat) is expected to remain fairly limited. ..Moore/Gleason.. 07/12/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...IND...PAH...ILX...MEG...LSX...LZK...SGF... LAT...LON 38508743 38328771 37998802 37548811 37008821 36728848 36568909 36179004 36179077 36169121 36539134 36839120 37179041 37518984 37948958 38188946 38488942 38748915 38978878 39068847 39058804 38948760 38788743 38508743 Read more

MD 1586 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR THE NORTHERN/CENTRAL HIGH PLAINS
Mesoscale Discussion 1586 NWS Storm Prediction Center Norman OK 0444 PM CDT Fri Jul 12 2024 Areas affected...the northern/central High Plains Concerning...Severe potential...Watch unlikely Valid 122144Z - 122315Z Probability of Watch Issuance...5 percent SUMMARY...Sporadic and highly localized severe wind gusts will be possible within dry microbursts from northeast Wyoming and western South Dakota into northeast Colorado through sunset. DISCUSSION...Isolated high-based, low-topped convection is underway adjacent to the Big Horns, north of the Black Hills, and into northeast Colorado along a lee thermal trough. Surface-temperature dew point spreads where convection is initiating are around 50-55 F, indicative of a deeply mixed boundary layer over the High Plains. As such, MLCAPE values are largely around the 500-1000 J/kg where convection is forming, but do increase with eastern extent towards the lower plains. This initial activity is expected to struggle to substantially deepen given the airmass, yielded a predominant dry microburst wind threat across the region for the first few hours of development. Moderate northwesterly speed shear within the cloud-bearing layer may promote small hail production in the strongest cores, which could augment downdrafts as they fall. ..Grams/Gleason.. 07/12/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LBF...UNR...GLD...BOU...CYS...BYZ...RIW... LAT...LON 44860624 45350520 45210270 44800166 43000163 40150186 39950224 40010280 40490305 43140425 44080647 44860624 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Fri Jul 12 2024 Valid 122000Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER MUCH OF THE NORTHERN PLAINS...A SMALL PART OF THE LOWER OHIO VALLEY INTO NORTHERN ARKANSAS...AND A SMALL PART OF NORTHWEST ARIZONA... ...SUMMARY... Isolated severe wind and hail will be possible over the northern and central Great Plains from late afternoon into tonight, and this afternoon from the Ozarks to lower Ohio Valley. A Marginal Risk remains in effect for parts of the northern Plains. Storms will form later this afternoon within the surface trough near the eastern borders of MT and WY, with locally severe gusts or marginal hail possible. Additional storms may move across eastern ND into northwest MN late tonight into early Saturday morning, as the SK/MB upper trough skirts the area. To the southwest, isolated storms that develop over northern parts of the Mogollon Rim may produce localized strong gusts later this afternoon as outflows push southwestward into the deeply mixed boundary layer. Precipitable water values up to 0.75" should be sufficient for outflow production with a general west/southwest motion. ..Jewell.. 07/12/2024 .PREV DISCUSSION... /ISSUED 1123 AM CDT Fri Jul 12 2024/ ...Northern Plains... Broad diffluent northwesterly mid-level flow is present today across the northern Plains states. Full sunshine over the region will result in hot surface temperatures and inverted-v thermodynamic profiles from eastern MT/WY into the western Dakotas. Most morning CAM solutions suggest scattered high-based thunderstorm development by late afternoon, with activity spreading slowly eastward through the evening. Locally gusty/damaging winds are the main concern with these storms. Greater instability exists farther east in ND/SD/NE but will remain capped in most areas, unless congealing outflow from the west can intercept the higher theta-e air with some risk of wind/hail in the strongest cells. ...Southern MO/IL... Morning visible satellite imagery shows a remnant MCV over southern MO tracking slowly eastward. Ample low-level moisture and CAPE ahead of this system will likely result in scattered afternoon thunderstorms. Winds aloft are relatively weak, and convection should remain rather disorganized. However, the strongest storms could pose a risk of locally gusty winds. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Fri Jul 12 2024 Valid 122000Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER MUCH OF THE NORTHERN PLAINS...A SMALL PART OF THE LOWER OHIO VALLEY INTO NORTHERN ARKANSAS...AND A SMALL PART OF NORTHWEST ARIZONA... ...SUMMARY... Isolated severe wind and hail will be possible over the northern and central Great Plains from late afternoon into tonight, and this afternoon from the Ozarks to lower Ohio Valley. A Marginal Risk remains in effect for parts of the northern Plains. Storms will form later this afternoon within the surface trough near the eastern borders of MT and WY, with locally severe gusts or marginal hail possible. Additional storms may move across eastern ND into northwest MN late tonight into early Saturday morning, as the SK/MB upper trough skirts the area. To the southwest, isolated storms that develop over northern parts of the Mogollon Rim may produce localized strong gusts later this afternoon as outflows push southwestward into the deeply mixed boundary layer. Precipitable water values up to 0.75" should be sufficient for outflow production with a general west/southwest motion. ..Jewell.. 07/12/2024 .PREV DISCUSSION... /ISSUED 1123 AM CDT Fri Jul 12 2024/ ...Northern Plains... Broad diffluent northwesterly mid-level flow is present today across the northern Plains states. Full sunshine over the region will result in hot surface temperatures and inverted-v thermodynamic profiles from eastern MT/WY into the western Dakotas. Most morning CAM solutions suggest scattered high-based thunderstorm development by late afternoon, with activity spreading slowly eastward through the evening. Locally gusty/damaging winds are the main concern with these storms. Greater instability exists farther east in ND/SD/NE but will remain capped in most areas, unless congealing outflow from the west can intercept the higher theta-e air with some risk of wind/hail in the strongest cells. ...Southern MO/IL... Morning visible satellite imagery shows a remnant MCV over southern MO tracking slowly eastward. Ample low-level moisture and CAPE ahead of this system will likely result in scattered afternoon thunderstorms. Winds aloft are relatively weak, and convection should remain rather disorganized. However, the strongest storms could pose a risk of locally gusty winds. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Fri Jul 12 2024 Valid 122000Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER MUCH OF THE NORTHERN PLAINS...A SMALL PART OF THE LOWER OHIO VALLEY INTO NORTHERN ARKANSAS...AND A SMALL PART OF NORTHWEST ARIZONA... ...SUMMARY... Isolated severe wind and hail will be possible over the northern and central Great Plains from late afternoon into tonight, and this afternoon from the Ozarks to lower Ohio Valley. A Marginal Risk remains in effect for parts of the northern Plains. Storms will form later this afternoon within the surface trough near the eastern borders of MT and WY, with locally severe gusts or marginal hail possible. Additional storms may move across eastern ND into northwest MN late tonight into early Saturday morning, as the SK/MB upper trough skirts the area. To the southwest, isolated storms that develop over northern parts of the Mogollon Rim may produce localized strong gusts later this afternoon as outflows push southwestward into the deeply mixed boundary layer. Precipitable water values up to 0.75" should be sufficient for outflow production with a general west/southwest motion. ..Jewell.. 07/12/2024 .PREV DISCUSSION... /ISSUED 1123 AM CDT Fri Jul 12 2024/ ...Northern Plains... Broad diffluent northwesterly mid-level flow is present today across the northern Plains states. Full sunshine over the region will result in hot surface temperatures and inverted-v thermodynamic profiles from eastern MT/WY into the western Dakotas. Most morning CAM solutions suggest scattered high-based thunderstorm development by late afternoon, with activity spreading slowly eastward through the evening. Locally gusty/damaging winds are the main concern with these storms. Greater instability exists farther east in ND/SD/NE but will remain capped in most areas, unless congealing outflow from the west can intercept the higher theta-e air with some risk of wind/hail in the strongest cells. ...Southern MO/IL... Morning visible satellite imagery shows a remnant MCV over southern MO tracking slowly eastward. Ample low-level moisture and CAPE ahead of this system will likely result in scattered afternoon thunderstorms. Winds aloft are relatively weak, and convection should remain rather disorganized. However, the strongest storms could pose a risk of locally gusty winds. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Fri Jul 12 2024 Valid 122000Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER MUCH OF THE NORTHERN PLAINS...A SMALL PART OF THE LOWER OHIO VALLEY INTO NORTHERN ARKANSAS...AND A SMALL PART OF NORTHWEST ARIZONA... ...SUMMARY... Isolated severe wind and hail will be possible over the northern and central Great Plains from late afternoon into tonight, and this afternoon from the Ozarks to lower Ohio Valley. A Marginal Risk remains in effect for parts of the northern Plains. Storms will form later this afternoon within the surface trough near the eastern borders of MT and WY, with locally severe gusts or marginal hail possible. Additional storms may move across eastern ND into northwest MN late tonight into early Saturday morning, as the SK/MB upper trough skirts the area. To the southwest, isolated storms that develop over northern parts of the Mogollon Rim may produce localized strong gusts later this afternoon as outflows push southwestward into the deeply mixed boundary layer. Precipitable water values up to 0.75" should be sufficient for outflow production with a general west/southwest motion. ..Jewell.. 07/12/2024 .PREV DISCUSSION... /ISSUED 1123 AM CDT Fri Jul 12 2024/ ...Northern Plains... Broad diffluent northwesterly mid-level flow is present today across the northern Plains states. Full sunshine over the region will result in hot surface temperatures and inverted-v thermodynamic profiles from eastern MT/WY into the western Dakotas. Most morning CAM solutions suggest scattered high-based thunderstorm development by late afternoon, with activity spreading slowly eastward through the evening. Locally gusty/damaging winds are the main concern with these storms. Greater instability exists farther east in ND/SD/NE but will remain capped in most areas, unless congealing outflow from the west can intercept the higher theta-e air with some risk of wind/hail in the strongest cells. ...Southern MO/IL... Morning visible satellite imagery shows a remnant MCV over southern MO tracking slowly eastward. Ample low-level moisture and CAPE ahead of this system will likely result in scattered afternoon thunderstorms. Winds aloft are relatively weak, and convection should remain rather disorganized. However, the strongest storms could pose a risk of locally gusty winds. Read more

No Mesoscale Discussions are in effect as of Fri Jul 12 20:05:02 UTC 2024.

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0258 PM CDT Fri Jul 12 2024 Valid 131200Z - 141200Z The current D2 Fire Weather largely remains on track with only minor adjustments needed to bring isolated dry thunder into portions of southern California. Sounding analysis supports potential for high-based storms, with little to no measurable precipitation within this region. Fuels within this region remain critically dry, further supported by recent fire activity. See previous discussion for more information. ..Thornton.. 07/12/2024 .PREV DISCUSSION... /ISSUED 0224 AM CDT Fri Jul 12 2024/ ...Synopsis... Fire weather concerns will continue into the weekend across the western U.S. - especially across the Great Basin where isolated to scattered dry thunderstorms are expected to develop by mid-afternoon and persist into the overnight hours. Continued hot/dry conditions are expected across much of the West, with breezy winds likely across portions of the Pacific Northwest and northern Rockies on the northern periphery of a dominant upper ridge centered over the southern Great Basin. ...Dry Thunderstorms - Sierra Nevada and the Great Basin... A weak mid-level low is noted in early-morning water-vapor imagery off the CA coast to the west of a more dominant upper ridge. Concurrently, a plume of 0.5-0.9 inch PWAT values is slowly migrating northward from southern/central CA. This moisture will continue to spread north over the next 48 hours and will phase with the mid-level impulse as it moves north Saturday afternoon/overnight. The combination of increasing mid-level moisture atop very dry boundary-layer conditions - along with 20-25 knot mean storm motions - will support the potential for dry thunderstorms. Forecast guidance suggests thunderstorms will initially develop across the southern Sierra Nevada into the lower CO River Valley Saturday afternoon around peak heating, slowly spreading north during the evening and overnight hours. Ensemble guidance currently depicts low (30% or lower) probability for wetting rainfall, and recent fuel guidance indicates that lightning-ignition efficiency is fairly high (15-20%) along the Sierra Nevada and into central NV/southern OR/ID. Consequently, dry lightning concerns are likely, and an upgrade to Scattered Dry Thunderstorms may be warranted if a corridor of higher thunderstorm potential becomes apparent in high-res guidance. ...Pacific Northwest/northwest Nevada and ID/MT... Hot/dry conditions are expected to continue across the Pacific Northwest with another day of RH values in the single digits to low teens. A belt of strong mid-level flow should reside across the Cascades/northern Sierra Nevada into the northern Rockies, which will maintain lee troughing across eastern OR/WA and across the northern High Plains. A combination of modest gradient winds, downslope wind enhancement, and deep boundary-layer mixing should yield areas of 15-20 mph winds coincident with very dry conditions. Elevated fire weather conditions appear likely with localized critical conditions possible. ...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 0258 PM CDT Fri Jul 12 2024 Valid 131200Z - 141200Z The current D2 Fire Weather largely remains on track with only minor adjustments needed to bring isolated dry thunder into portions of southern California. Sounding analysis supports potential for high-based storms, with little to no measurable precipitation within this region. Fuels within this region remain critically dry, further supported by recent fire activity. See previous discussion for more information. ..Thornton.. 07/12/2024 .PREV DISCUSSION... /ISSUED 0224 AM CDT Fri Jul 12 2024/ ...Synopsis... Fire weather concerns will continue into the weekend across the western U.S. - especially across the Great Basin where isolated to scattered dry thunderstorms are expected to develop by mid-afternoon and persist into the overnight hours. Continued hot/dry conditions are expected across much of the West, with breezy winds likely across portions of the Pacific Northwest and northern Rockies on the northern periphery of a dominant upper ridge centered over the southern Great Basin. ...Dry Thunderstorms - Sierra Nevada and the Great Basin... A weak mid-level low is noted in early-morning water-vapor imagery off the CA coast to the west of a more dominant upper ridge. Concurrently, a plume of 0.5-0.9 inch PWAT values is slowly migrating northward from southern/central CA. This moisture will continue to spread north over the next 48 hours and will phase with the mid-level impulse as it moves north Saturday afternoon/overnight. The combination of increasing mid-level moisture atop very dry boundary-layer conditions - along with 20-25 knot mean storm motions - will support the potential for dry thunderstorms. Forecast guidance suggests thunderstorms will initially develop across the southern Sierra Nevada into the lower CO River Valley Saturday afternoon around peak heating, slowly spreading north during the evening and overnight hours. Ensemble guidance currently depicts low (30% or lower) probability for wetting rainfall, and recent fuel guidance indicates that lightning-ignition efficiency is fairly high (15-20%) along the Sierra Nevada and into central NV/southern OR/ID. Consequently, dry lightning concerns are likely, and an upgrade to Scattered Dry Thunderstorms may be warranted if a corridor of higher thunderstorm potential becomes apparent in high-res guidance. ...Pacific Northwest/northwest Nevada and ID/MT... Hot/dry conditions are expected to continue across the Pacific Northwest with another day of RH values in the single digits to low teens. A belt of strong mid-level flow should reside across the Cascades/northern Sierra Nevada into the northern Rockies, which will maintain lee troughing across eastern OR/WA and across the northern High Plains. A combination of modest gradient winds, downslope wind enhancement, and deep boundary-layer mixing should yield areas of 15-20 mph winds coincident with very dry conditions. Elevated fire weather conditions appear likely with localized critical conditions possible. ...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 0258 PM CDT Fri Jul 12 2024 Valid 131200Z - 141200Z The current D2 Fire Weather largely remains on track with only minor adjustments needed to bring isolated dry thunder into portions of southern California. Sounding analysis supports potential for high-based storms, with little to no measurable precipitation within this region. Fuels within this region remain critically dry, further supported by recent fire activity. See previous discussion for more information. ..Thornton.. 07/12/2024 .PREV DISCUSSION... /ISSUED 0224 AM CDT Fri Jul 12 2024/ ...Synopsis... Fire weather concerns will continue into the weekend across the western U.S. - especially across the Great Basin where isolated to scattered dry thunderstorms are expected to develop by mid-afternoon and persist into the overnight hours. Continued hot/dry conditions are expected across much of the West, with breezy winds likely across portions of the Pacific Northwest and northern Rockies on the northern periphery of a dominant upper ridge centered over the southern Great Basin. ...Dry Thunderstorms - Sierra Nevada and the Great Basin... A weak mid-level low is noted in early-morning water-vapor imagery off the CA coast to the west of a more dominant upper ridge. Concurrently, a plume of 0.5-0.9 inch PWAT values is slowly migrating northward from southern/central CA. This moisture will continue to spread north over the next 48 hours and will phase with the mid-level impulse as it moves north Saturday afternoon/overnight. The combination of increasing mid-level moisture atop very dry boundary-layer conditions - along with 20-25 knot mean storm motions - will support the potential for dry thunderstorms. Forecast guidance suggests thunderstorms will initially develop across the southern Sierra Nevada into the lower CO River Valley Saturday afternoon around peak heating, slowly spreading north during the evening and overnight hours. Ensemble guidance currently depicts low (30% or lower) probability for wetting rainfall, and recent fuel guidance indicates that lightning-ignition efficiency is fairly high (15-20%) along the Sierra Nevada and into central NV/southern OR/ID. Consequently, dry lightning concerns are likely, and an upgrade to Scattered Dry Thunderstorms may be warranted if a corridor of higher thunderstorm potential becomes apparent in high-res guidance. ...Pacific Northwest/northwest Nevada and ID/MT... Hot/dry conditions are expected to continue across the Pacific Northwest with another day of RH values in the single digits to low teens. A belt of strong mid-level flow should reside across the Cascades/northern Sierra Nevada into the northern Rockies, which will maintain lee troughing across eastern OR/WA and across the northern High Plains. A combination of modest gradient winds, downslope wind enhancement, and deep boundary-layer mixing should yield areas of 15-20 mph winds coincident with very dry conditions. Elevated fire weather conditions appear likely with localized critical conditions possible. ...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 0258 PM CDT Fri Jul 12 2024 Valid 131200Z - 141200Z The current D2 Fire Weather largely remains on track with only minor adjustments needed to bring isolated dry thunder into portions of southern California. Sounding analysis supports potential for high-based storms, with little to no measurable precipitation within this region. Fuels within this region remain critically dry, further supported by recent fire activity. See previous discussion for more information. ..Thornton.. 07/12/2024 .PREV DISCUSSION... /ISSUED 0224 AM CDT Fri Jul 12 2024/ ...Synopsis... Fire weather concerns will continue into the weekend across the western U.S. - especially across the Great Basin where isolated to scattered dry thunderstorms are expected to develop by mid-afternoon and persist into the overnight hours. Continued hot/dry conditions are expected across much of the West, with breezy winds likely across portions of the Pacific Northwest and northern Rockies on the northern periphery of a dominant upper ridge centered over the southern Great Basin. ...Dry Thunderstorms - Sierra Nevada and the Great Basin... A weak mid-level low is noted in early-morning water-vapor imagery off the CA coast to the west of a more dominant upper ridge. Concurrently, a plume of 0.5-0.9 inch PWAT values is slowly migrating northward from southern/central CA. This moisture will continue to spread north over the next 48 hours and will phase with the mid-level impulse as it moves north Saturday afternoon/overnight. The combination of increasing mid-level moisture atop very dry boundary-layer conditions - along with 20-25 knot mean storm motions - will support the potential for dry thunderstorms. Forecast guidance suggests thunderstorms will initially develop across the southern Sierra Nevada into the lower CO River Valley Saturday afternoon around peak heating, slowly spreading north during the evening and overnight hours. Ensemble guidance currently depicts low (30% or lower) probability for wetting rainfall, and recent fuel guidance indicates that lightning-ignition efficiency is fairly high (15-20%) along the Sierra Nevada and into central NV/southern OR/ID. Consequently, dry lightning concerns are likely, and an upgrade to Scattered Dry Thunderstorms may be warranted if a corridor of higher thunderstorm potential becomes apparent in high-res guidance. ...Pacific Northwest/northwest Nevada and ID/MT... Hot/dry conditions are expected to continue across the Pacific Northwest with another day of RH values in the single digits to low teens. A belt of strong mid-level flow should reside across the Cascades/northern Sierra Nevada into the northern Rockies, which will maintain lee troughing across eastern OR/WA and across the northern High Plains. A combination of modest gradient winds, downslope wind enhancement, and deep boundary-layer mixing should yield areas of 15-20 mph winds coincident with very dry conditions. Elevated fire weather conditions appear likely with localized critical conditions possible. ...Please see www.spc.noaa.gov/fire for graphic product... Read more