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SPC Tornado/Severe Thunderstorm Alerts (UNOFFICIAL)
@spc-storms.nws-bot.us
Unofficial bot sharing alerts from SPC Tornado/Severe Thunderstorm Watches. This account is not monitored. Contact @wandrme.paxex.aero if needed.
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SPC Oct 4, 2024 0600 UTC Day 2 Convective Outlook ⛈️NO SEVERE THUNDERSTORM AREAS FORECAST🌪️ Additional Details Here.

Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1221 AM CDT Fri Oct 04 2024 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Potential for severe storms appears low on Saturday. ...Upper Midwest into the Upper Great Lakes... Northern-stream shortwave trough is forecast to move quickly eastward from the Canadian Prairies and adjacent northern High Plains through western Ontario and the Upper Midwest on Saturday. This shortwave is expected to mature as it progresses eastward, with the resulting closed mid-level cyclone over northwestern Ontario by early Sunday morning. An associated surface low will accompany this system, moving eastward across the central portion of Canadian Prairie Provinces and ending the period stacked beneath the mid-level low over northwestern Ontario. Cold front attendant to this surface low will push eastward across the northern and central Plains through the Upper Midwest. By 12Z Sunday, this front will likely extend from central Lower MI southwestward through central MO before then turning more westward and extending along the OK/KS border vicinity. Warm-air advection will gradually increase within the warm sector ahead of the front throughout the period. Low to mid-level moistening from this warm-air advection coupled with cooling mid-level temperatures will result in elevated buoyancy across the Upper Midwest and Upper Great Lakes from Saturday evening into Sunday morning. Isolated thunderstorms are possible within this region as a result. Enhanced mid-level flow associated with the shortwave trough will spread into the region during the evening as well, supporting moderate to strong deep-layer vertical shear. However, the cloud-bearing layer shear values will be more modest (i.e. around half of the bulk shear values), and the resulting combination of modest buoyancy and shear will likely result in predominantly sub-severe thunderstorms. ...Gulf Coast... Showers and thunderstorms are expected across the Gulf Coast and FL Peninsula throughout the period as low-level easterlies persist within a very moist airmass. Limited buoyancy and weak shear should keep the severe-thunderstorm potential low. ..Mosier.. 10/04/2024
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SPC Oct 4, 2024 0600 UTC Day 1 Convective Outlook ⛈️NO SEVERE THUNDERSTORM AREAS FORECAST🌪️ Additional Details Here.

Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1133 PM CDT Thu Oct 03 2024 Valid 041200Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms appears negligible across the U.S. today through tonight. ...Discussion... Seasonably high moisture content will generally remain confined to where the low-level easterlies prevail, across the southwestern Atlantic through the Gulf Basin during this period. The boundary layer does remain relatively moist across much of the southeastern U.S., but this region, and most areas east of the Mississippi Valley, are forecast to remain under the influence of surface high pressure. Still, weak to modest destabilization and orographic forcing with daytime heating may contribute to some thunderstorm development today across parts of the upper Tennessee Valley and Cumberland Plateau into the Blue Ridge. Otherwise, higher thunderstorm probabilities likely will remain focused across southern portions of the Florida Peninsula and immediate northwestern through north central Gulf coastal areas. An area of thunderstorm development, largely aided by ascent associated with lower/mid-tropospheric warm advection, may be ongoing at 12Z this morning across parts of southeastern Iowa and adjacent northeastern Missouri/west central Illinois. But this appears likely to gradually diminish while slowly spreading southeastward across west central/central Illinois through mid to late morning. The stronger westerlies remain confined to the northern mid-latitudes, with one rather vigorous embedded short wave trough forecast to rapidly accelerate inland of the Pacific Northwest coast and across the northern Rockies by 12Z Saturday. Models indicate that this will be accompanied by cyclogenesis to the lee of the Canadian Rockies, and strong pre- and post-frontal lower/mid-tropospheric wind fields across the northern U.S. Rockies into Great Plains. Despite rather dry initial conditions, strong mid/upper forcing for ascent may contribute to at least weak high-based convection, near or above/to the cool side of the surging cold front. While it is possible that this could coincide with strong/gusty surface conditions, forecast soundings suggest minimal potential for these gusts to be related to moist convective processes, and it still appears unlikely that this convection will be accompanied by much, if any, lightning. ..Kerr/Squitieri.. 10/04/2024
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SPC Oct 4, 2024 0100 UTC Day 1 Convective Outlook ⛈️THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TONIGHT ACROSS PARTS OF SOUTHEASTERN IOWA🌪️ Additional Details Here.

Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0749 PM CDT Thu Oct 03 2024 Valid 040100Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TONIGHT ACROSS PARTS OF SOUTHEASTERN IOWA...ADJACENT NORTHEASTERN MISSOURI AND WEST CENTRAL ILLINOIS... ...SUMMARY... An area of developing thunderstorms overnight may pose a risk for small to marginally severe hail across parts of southeastern Iowa, adjacent northeastern Missouri and west central Illinois. ...01Z Update... Within the mid-latitude westerlies, one notable short wave trough is forecast to continue digging across the northern Great Plains Red River Valley toward the upper Great Lakes region tonight. The southern periphery of the surrounding cyclonic mid/upper-level flow currently curves across southern Nebraska through the Missouri/Iowa border vicinity, where it is beginning to overspread an initially quasi-stationary frontal zone. Models suggest that this regime will become increasingly divergent late this evening into the overnight hours, contributing to increasing forcing for ascent. Lower/mid-level ascent is already increasing across Iowa and surrounding portions of the Missouri Valley/Upper Midwest, in response to warm advection. It appears that this will lead to increasing thunderstorm development by 05-07Z across parts of central/southern Iowa, where guidance indicates a corridor of modest destabilization is possible associated with weak elevated moisture return above the frontal zone. Forecast soundings indicate most unstable CAPE may increase in excess of 1000 J/kg along this corridor, in the presence of modest potential cloud-bearing layer shear. Thermodynamic profiles may include sufficiently cool mid-levels (and steep lapse rates) to support a risk for marginally severe hail (up to around 1 inch or so in diameter) in a few of the stronger storms. ..Kerr.. 10/04/2024
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SPC Oct 3, 2024 2000 UTC Day 1 Convective Outlook ⛈️NO SEVERE THUNDERSTORM AREAS FORECAST🌪️ Additional Details Here.

Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Thu Oct 03 2024 Valid 032000Z - 041200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast. However, a few strong storms are expected over parts of Iowa tonight. ...20Z Update... Scattered storms persist across the central FL Peninsula within a moist easterly flow regime south of the upper ridge. Moderate instability may support locally strong gusts within the diurnal and weakly sheared regime. To the west, a small area of strong thunderstorm potential is forecast from IA into northwest IL after 06Z, in association with a shortwave trough moving across the upper MS Valley. Lift near the 850 mb front along with steepening lapse rates may yield an elevated cluster of storms forming over south-central IA. Radar presentation of the initial activity may indicate hail in the strongest storm cores, but this may be short lived due to merging updrafts over time. While severe hail is not currently forecast, at least small hail appears likely. ..Jewell.. 10/03/2024 .PREV DISCUSSION... /ISSUED 1123 AM CDT Thu Oct 03 2024/ ...Synopsis/Discussion... Morning surface observations depict a southwest/northeast-oriented quasi-stationary boundary extending from the central Plains into the Mid/Upper MS Valley. Within the base of a large-scale trough over the north-central CONUS, an embedded shortwave trough and related lift will overspread the boundary during the overnight/early morning hours. The associated low-level mass response will favor the east-northeastward movement of a weak frontal-wave low along the boundary -- promoting isolated to widely scattered elevated thunderstorms atop the frontal surface in the 06-12Z time frame (generally focused over eastern IA and northwest IL). Around 30-40 kt of effective shear could lead to a couple embedded cells capable of small to marginally severe hail initially, though the steeper midlevel lapse-rate plume and favorable instability should be displaced to the south of this activity -- generally limiting the severe threat.
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SPC Oct 3, 2024 1930 UTC Day 3 Severe Thunderstorm Outlook ⛈️NO SEVERE THUNDERSTORM AREAS FORECAST🌪️ Additional Details Here.

Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0219 PM CDT Thu Oct 03 2024 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Potential for severe storms appears low on Saturday. ...Discussion... A strong mid-level short-wave trough within fast northern-stream flow over the northern U.S. will cross the northern Plains and eventually move into the Upper Great Lakes region Saturday. Accompanying this trough, a surface low will advance quickly across the Canadian Prairie while a trailing cold front shifts southeastward across the northern and eventually the central Plains, and the Upper Midwest region, through the period. Scattered showers and a few thunderstorms should again affect southeastern Atlantic and Gulf Coast areas, while showers and thunderstorms also evolve during the afternoon and evening across the Upper Mississippi Valley/Upper Great Lakes area. Here, modest low-level moisture but steepening mid-level lapse rates suggests that convection should remain largely elevated atop a weakly stable boundary layer. Still, with strong west-southwesterly flow through the lower half of the troposphere, a few stronger updrafts -- possibly capable of producing hail or even locally gusty winds -- may occur. At this time, any risk for severe-caliber events appears likely to remain low, and thus no hail/wind probabilities will be included at this time. ..Goss.. 10/03/2024
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SPC Oct 3, 2024 1730 UTC Day 2 Convective Outlook ⛈️NO SEVERE THUNDERSTORM AREAS FORECAST🌪️ Additional Details Here.

Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1225 PM CDT Thu Oct 03 2024 Valid 041200Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Friday. ...Discussion... A fast/progressive upper flow field will persist across the northern third of the U.S. Friday, while ridging generally prevails over the southern two-thirds of the country. Once exception will be a weak upper disturbance shifting out of the northern Gulf of Mexico, which will partially phase with a northern-stream trough crossing the Great Lakes region. By the end of the period, this trough will reach New England and the Atlantic Coast. At the surface, a cold front will cross the northern Intermountain region and eventually emerge into the northern Plains, ahead of a trough embedded in the fast northern-stream flow field aloft. Otherwise, a rather nondescript surface pattern will prevail elsewhere. At low levels, tropical moisture will be confined to the Gulf and Southeast Coasts. Lesser moisture -- dewpoints in the upper 50s to low 60s -- will extend northward across the Tennessee, Ohio, Mid-Mississippi, and Mid Missouri Valleys, but weak lapse rates aloft across these areas will yield only modest destabilization. Greatest thunderstorm potential will extend from the Texas Coastal Plain eastward across the Southeast -- aided by ascent associated with the aforementioned southeastern U.S. upper disturbance phasing with a northern-stream trough, and other vorticity maxima extending westward across the Gulf and into northern Mexico. Elevated showers and a few thunderstorms will also be possible early in the period over the northeastern Missouri/southeastern Iowa/northern Illinois area. In all of these locales, severe weather is not expected. ..Goss.. 10/03/2024
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SPC Oct 3, 2024 1630 UTC Day 1 Convective Outlook ⛈️NO SEVERE THUNDERSTORM AREAS FORECAST🌪️ Additional Details Here.

Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1123 AM CDT Thu Oct 03 2024 Valid 031630Z - 041200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...Synopsis/Discussion... Morning surface observations depict a southwest/northeast-oriented quasi-stationary boundary extending from the central Plains into the Mid/Upper MS Valley. Within the base of a large-scale trough over the north-central CONUS, an embedded shortwave trough and related lift will overspread the boundary during the overnight/early morning hours. The associated low-level mass response will favor the east-northeastward movement of a weak frontal-wave low along the boundary -- promoting isolated to widely scattered elevated thunderstorms atop the frontal surface in the 06-12Z time frame (generally focused over eastern IA and northwest IL). Around 30-40 kt of effective shear could lead to a couple embedded cells capable of small to marginally severe hail initially, though the steeper midlevel lapse-rate plume and favorable instability should be displaced to the south of this activity -- generally limiting the severe threat. ..Weinman.. 10/03/2024
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SPC Oct 3, 2024 1300 UTC Day 1 Convective Outlook ⛈️NO SEVERE THUNDERSTORM AREAS FORECAST🌪️ Additional Details Here.

Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0736 AM CDT Thu Oct 03 2024 Valid 031300Z - 041200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...Synopsis/Discussion... In mid/upper levels, a nearly zonal northern-stream pattern will prevail either side of the Canadian border, from the Pacific Coast across the Great Lakes to New England. The main feature perturbing that belt for this period will be a strongly positively tilted trough, currently over south-central parts of SK/MB northwestward to north-central AB. This trough will amplify and pivot southeastward/ eastward across northern ON, northern MN and Lake Superior into tonight. By 12Z, the trailing part of this feature should be moving across the western U.P of MI, northern WI and central MN. A weak shortwave trough -- evident in moisture-channel imagery over eastern OR and southwestern ID -- may reach the Quad Cities area of IA/IL by 12Z tomorrow and phase with the larger trough. At the surface, 11Z analysis showed a frontal wave low over northwestern KS, with warm front eastward to west-central/ northwestern MO, and cold front across east-central CO. The low should migrate eastward through the period, reaching north-central/ northwestern MO by 12Z, with cold front trailing across southern KS, western OK and the TX South Plains, and warm front extending to east-central MO and southern IL. ...Mid/upper Mississippi Valley... Capping and meager boundary-layer moisture will inhibit convective potential today along/ahead of the front and low. However, an area of isolated to scattered elevated thunderstorms is possible overnight northeast of the low, supported by large-scale DCVA/lift ahead of the ejecting shortwave trough, and warm advection/ isentropic lift to LFC of increasingly moist parcels above the surface. Activity should be rooted in the 700-800-mb layer, amidst MUCAPE roughly 500-800 J/kg, and around 35-40 kt effective-shear magnitudes. This may support small hail, especially early in the convective cycle when cells are still at least somewhat discrete. Modes should become messier and precip more expansive fairly quickly, as inflow-layer moisture and MUCAPE only slowly increase in the immediate upstream airmass to the southwest. The overall severe threat appears too limited and conditional for an outlook at this time. ..Edwards/Dean.. 10/03/2024
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SPC Oct 3, 2024 Day 4-8 Severe Weather Outlook ⛈️DISCUSSION🌪️ Additional Details Here.

Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0339 AM CDT Thu Oct 03 2024 Valid 061200Z - 111200Z ...DISCUSSION... A strong upper trough will broaden across the Upper Midwest into parts of the Northeast on Sunday. An associated cold front will move through the upper Ohio Valley on Sunday and off the Mid-Atlantic Coast early to mid morning on Monday. Thereafter, broad troughing will remain in the Northeast until late in the week as an expansive upper ridge envelops much of the CONUS. ...Upper-Ohio Valley Vicinity... The cold front will continue eastward on Sunday, moving through Ohio during the mid/late afternoon. Moisture return ahead of the front will be the main source of uncertainty in terms of how much severe threat there could be. Mid-level forcing will be sufficient, but low-level veering ahead of the front suggests uncertain storm coverage. A conditional threat for damaging winds exists during the late afternoon.
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SPC Oct 3, 2024 0730 UTC Day 3 Severe Thunderstorm Outlook ⛈️NO SEVERE THUNDERSTORM AREAS FORECAST🌪️ Additional Details Here.

Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0222 AM CDT Thu Oct 03 2024 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Potential for severe storms appears low on Saturday. ...Synopsis... A potent upper-level shortwave trough will make quick progress across the northern Plains and move into the upper Mississippi Valley by early evening. A deep surface cyclone within the Canadian Prairie will move east along with its parent upper-level system. Attendant to this cyclone, a cold front will quickly through Minnesota, Wisconsin, and eventually much of Michigan by early Sunday morning. ...Upper-Mississippi Valley Vicinity... Ahead of the cold front, some moisture return is expected to occur. However, this moisture return will have no connection to the Gulf due to a previous frontal passage to near the Gulf Coast. Lack of low-level moisture will likely preclude any potential for surface-based storms. By early evening, strong mid-level ascent, linear frontal forcing, and 850 mb warm air advection should promote scattered storm development from the Mississippi Valley into parts of Wisconsin. Deep-layer winds will be strong, but effective shear will only be marginal given the elevated nature of the convection. 500-1000 J/kg MUCAPE could support some stronger updrafts that could produce small hail. The marginal effective shear and messy storm modes should preclude any greater risk. ..Wendt.. 10/03/2024
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SPC Tornado/Severe Thunderstorm Alerts (UNOFFICIAL)
@spc-storms.nws-bot.us
Unofficial bot sharing alerts from SPC Tornado/Severe Thunderstorm Watches. This account is not monitored. Contact @wandrme.paxex.aero if needed.
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