Tuesday's high temperature will reach 63 degrees. By Tuesday night there will be chance for thunderstorms. The severe threat will be to our south; in the southern states. They will see tornadoes so warn your family and friends if they are in the shaded area below:
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CST Mon Nov 28 2022 Valid 291200Z - 301200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FOR CENTRAL/NORTHERN MISSISSIPPI...NORTHEAST LOUISIANA...SOUTHEAST ARKANSAS...EXTREME SOUTHWEST TENNESSEE... ...SUMMARY... Severe thunderstorms capable of producing tornadoes and wind damage, along with some hail, are expected Tuesday afternoon and evening, extending into the overnight period across parts of the lower to mid Mississippi Valley and parts of the Southeast. A few strong/long-track tornadoes will be possible. ...Synopsis... A deep and progressive mid/upper-level trough is forecast to move from the central/southern Rockies eastward Tuesday morning to parts of the Mississippi Valley region by early Wednesday. A surface cyclone initially over central KS will move quickly northeastward toward the Upper Great Lakes by Tuesday evening, as an attendant cold front sweeps through the Great Plains and eventually into the Midwest. ...Lower/mid MS Valley into the Southeast... The potential for several long-track supercells remains evident across parts of the lower/mid MS Valley late Tuesday afternoon into Tuesday night, with a threat of strong tornadoes, scattered wind damage, and hail. Seasonably rich low-level moisture will quickly stream northward across the lower/mid MS Valley region ahead of the cold front on Tuesday, aided by a strong southwesterly low-level jet. Meanwhile, modestly steep midlevel lapse rates will overspread the region, in advance of the deep/progressive mid/upper-level trough. This will result in the development of moderate buoyancy (MLCAPE in excess of 1500 J/kg) across the warm sector. This destabilization will be occurring within a strongly sheared environment supportive of organized storms, including supercells. Initially elevated convection is expected to gradually increase in coverage through the morning across the ArkLaTex region within a low-level warm advection regime, with additional development possible farther south across southern LA/MS where somewhat stronger heating is expected. A few surface-based supercells are expected to evolve by afternoon, which could potentially be longer-lived as they move northeastward through a moistening and strongly sheared environment. Favorable 0-1 km shear/SRH will support a tornado threat, though some uncertainty remains regarding the impact of potentially weak low-level lapse rates on the tornado potential. Any sustained supercells within the warm sector could pose a strong tornado threat, in addition to a risk of hail and damaging gusts. Storm coverage will continue to increase through the evening and overnight hours, with favorable low-level moisture and strong low-level and deep-layer shear continuing to support a threat of all severe hazards. Some tornado potential is likely to continue overnight across parts of MS into western/central AL. ...Parts of the OH Valley/Midwest... Weaker low-level moisture return is expected farther north into parts of the Midwest and Ohio Valley in advance of the cold front. Despite weak buoyancy, favorable large-scale ascent and strong deep-layer flow could support a threat of locally damaging gusts with any sustained low-topped convection. There is some potential for a damaging wind threat to spread farther north than currently indicated, and some northward expansion of wind probabilities is possible depending on shorter-term observational and guidance trends.
After that, it cools down for two days (Wednesday and Thursday) and then warms up into the 50's by Friday. A week from today or Tuesday December 6 is when we see winter trying to make a sustained effort to hang on. We'll see. Here is the analysis for Indiana:
.Long Term...(Tuesday Night through Monday) Issued at 258 PM EST Mon Nov 28 2022 * Strong to Severe Storms Tuesday Night * Gusty winds Tuesday Night into Wednesday * Much Colder Midweek Then a Warming Trend for Late Week * Unsettled Weather Returns This Weekend into Early Next Week The main focus in the long term period will be on the high impact storm system for Tuesday night and early Wednesday...bringing the potential for more rain along with a threat for strong to severe convection along and ahead of an intense cold front. As mentioned in the short term discussion...strong wind gusts and a rapid expansion of showers and a few storms will occur on Tuesday afternoon and be ongoing by Tuesday evening. The primary surface wave will be in the process of intensifying as it tracks through the upper Midwest Tuesday evening and eventually lifts towards James Bay by Wednesday morning. A rich sure of deep moisture will advect north Tuesday afternoon and evening ahead of the cold front with dewpoints surging into the mid and possibly upper 50s by the evening. As this system continues to evolve...the focus for significant severe weather has been highlighted for the lower Mississippi Valley for several days now with a higher uncertainty further north across the Ohio Valley due to a lesser low level moisture...buoyancy and instability presence. Despite that...the setup looks supportive of at least an isolated risk for severe convection reaching up into parts of the area by Tuesday evening with strong mid and upper level diffluence over the region...combined with high levels of BL shear and a 60+kt low level jet moving across the area. Climatology also supports the potential risk with the top CIPS analog of the 12/23/2015 QLCS that produced wind damage and a few spin up tornadoes across the forecast area. The timing with that event though was during the mid and late afternoon whereas the highest threat with this system will focus more during the evening and early overnight. That being said...little instability is necessary in these high shear/low CAPE environment where the dynamics and shear will help drive the risks. And as has been mentioned in previous discussions over the last day or so...the overnight timing will not mitigate the overall risk for severe weather even with surface instability largely being held south of the forecast area. Breaking it down further...there now appear to be two periods of interest within the broader timeframe from Tuesday evening through the predawn hours Wednesday. During the evening...confidence continues to grow in an increase in prefrontal convection expanding north from the lower Mississippi and Tennessee Valleys. While damaging winds will be a concern with any of the stronger convection...a subtly elevated brief spin up tornado risk would likely focus during the evening when 0-1km SRH values are enhanced and hodographs show impressive turning through the lowest 2-3km. This threat will largely diminish by 05Z or shortly after as the stronger shear and SRH values shift east. The focus will then shift to the second area of concern which will be a thin broken convective line poised to pivot across the forecast area with the cold front from west to east in the 06-09Z timeframe. By this point...the concern shifts almost solely to damaging winds along the line as the wind profile becomes more unidirectional and the boundary layer inversion present earlier in the night largely dissipates enabling any of the storms to mix down the stronger winds aloft. A narrow axis of 0-3km CAPE values will develop in tandem with the line and may even increase to levels above 100 j/kg as it transitions across the forecast area. While the bulk of the low level SRH has moved off to the east by this point...0-1km SRH values of 50-100 m2/s2 linger which would be enough to support a few mesovortices along the line. After 09Z...any severe risk is over with the front east of the region. To summarize the severe risks before we move on to the rest of the long term...potential exists from the evening through the predawn hours Wednesday. Damaging winds are the primary concern but prefrontal convection during the evening may also carry a threat for a few spin up tornadoes. QLCS style convective line then tracks across the forecast area overnight with the winds the primary risk. Also...little lightning and thunder may accompany the convection...a common feature in the Ohio Valley with cool season nocturnal convection within a high shear/low CAPE environment. Once the front passes early Wednesday...temperatures will drop rapidly as intense cold advection commences immediately. A few snowflakes may mix in as well prior to the precipitation ending. Outside of convection... winds will be gusty Tuesday night into Wednesday. The remainder of the extended will shift to a proverbial roller coaster as a sharply colder airmass in wake of the Tuesday night storm system settles over the region for midweek...then shifts back to a warmer regime by late week with a quasi-zonal flow pattern aloft resuming. High pressure will track across the eastern part of the country with dry weather Wednesday through Friday. Another surface low will track across the upper Midwest Friday night into Saturday morning but available moisture will be limited and only expecting scattered showers at this point. After a brief return of high pressure Saturday...the front will return north as a warm front for the second half of the weekend into early next week and at least at this early stage...appears to have the potential to produce an extended period of much needed rainfall Sunday through next Tuesday as surface waves ride along the boundary. There could be snow mixing in at times initially early Sunday but once the lingering cooler airmass gets pushed away to the north...rain is likely to be the predominant precip type. Highs Wednesday will likely hold in the mid and upper 30s behind the strong cold front...but expect a recovery back into the 50s by Friday and Saturday for parts of the region. Temperatures will continue to fluctuate in the 40s and 50s Sunday and Monday and will be dependent on the location of the frontal boundary.
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