jaxjagman

National Weather Service Memphis TN 344 PM CDT Tue Mar 16 2021 .DISCUSSION... The upper-low near the Four Corners continues to move east this afternoon with a well-defined baroclinic leaf downstream over the south-central CONUS. Pressure falls over the Southern Plains suggest surface cyclogenesis. This is verified by surface obs with a surface low and attendant triple point in northwest OK and a quasi-stationary front extending across AR into the TN Valley. Temperatures have overperformed by a few degrees with Memphis recording it`s first 80F reading of 2021 (last time was Nov 8). However, dewpoints have fallen into the 40s north of the stationary front resulting in a very pleasant afternoon. A few storms continue in the Starkville area, just south of the CWA, but we do expect this activity to gradually lift north along the warm front overnight. This convection is most likely after midnight. Strong shear and elevated instability may be sufficient to support a few weak, elevated supercells. With these storms being elevated, the primary risks will be hail up to the size of quarters and locally heavy rainfall. This convection will continue to lift north throughout the morning hours and is expected to reach the I-40 corridor after sunrise. Large scale forcing for ascent will be overspreading the CWA, steepening mid- level lapse rates and enhancing lift provided by warm advection and improving jet dynamics. Most of the convection by midday is expected to be in east AR or west TN with the warm sector across north MS likely seeing a bit of a lull. This lull will be important for destabilization. If we see a sufficient dry period, SBCAPE should be able to increase to 1500-2000 J/kg south of the warm front, whereas areas that remain in the muck will be see much more limited buoyancy. Shear will be quite strong with 0-6 km bulk wind difference near 60 kts. A few supercell structures are possible within the AM gunk, but will be more probable during the afternoon and evening hours where instability is stronger. If low-level warm advection and large scale ascent is sufficient to erode the cap, discrete supercells will be possible in the warm sector ahead of the cold front. This is the time for the greatest risk for strong (EF2+) tornadoes and sig hail (2+ inches). The cold front will approach the MS River after 00z, but storms are expected to develop along a pre-frontal trough during the mid/late afternoon hours. Strong line-normal shear will promote upscale growth, eventually forming into a QLCS. This QLCS will remain in a favorable environment for tornadoes and damaging wind as the low-level jet begins to intensify, but the large hail threat will begin to decrease. Several CAMs are representing 0-1 km storm relative helicity at or above 250 m2/s2 with Significant Tornado Parameter values of 1-3. As the line moves into west TN and north MS, we`ll maintain the risk for QLCS tornadoes and mesovortices. These tornadoes can develop quickly and it can be difficult to provide much lead time, especially far from the radar. Given the potential for nocturnal tornadoes, it is important to plan ahead and ensure you are capable of receiving timely weather alerts. In addition to the severe weather threat, locally heavy rainfall is possible. We`re looking at widespread 1-2" with localized higher amounts. This activity will largely end by 06z, but there may be some lingering showers and thunderstorms during the early morning hours. As the upper-low moves across the region on Thursday, expect scattered rain showers, mainly north of a Jonesboro- Savannah line. QPF with this precipitation should remain under 1/4 inch. Cooler and drier air will accompany Wednesday night`s cold front and will be ushered in by strong west winds. Wind gusts on Thursday may exceed 30 mph at times. Expect dry conditions and slightly below normal temperatures on Friday with highs in the low/mid 50s. Given the dry air and clear skies, it`s possible that some areas will experience a frost Saturday morning. We`ll continue to monitor these trends for the weekend. Otherwise, temperatures will moderate over the weekend with dry conditions continuing through Sunday. Rain chances return next week. More details on that system as it approaches.

National Weather Service Nashville TN 218 PM CDT Tue Mar 16 2021 ...Severe Weather is Likely in Middle TN on Wednesday... .DISCUSSION... Clouds have really hung tough across the southeastern half today. This has kept temperatures down for this area, but the sun is out in all its glory everywhere else across the mid-state and temperatures are responding with low to mid 70s at forecast time. I guess you could call today `the calm before the storm` because tomorrow and tomorrow night are going to be a different story. If you`ve been hiding under a rock (which is uncomfortable, by the way) for the last few days, we`ve been touting the idea that severe weather is on the way tomorrow and nothing has really changed that thought process. An upper level system taking shape over the southwestern U.S. right now will continue to intensify and push this direction overnight. As it does, a warm front will pull northward through our region providing ample moisture for storms to feed on. ** This is where part of the narrative has changed ** We`ve been questioning whether the warm front would pull far enough north to provide severe weather to most of Middle TN and it looks like this is going to happen. What this means is we`ll be dealing with three seperate time frames of concern: First, showers and thunderstorms will pull through the mid-state during the morning hours tomorrow. A few of these morning storms are going to be worth watching. There will be plenty of shear and just south of whereever the warm front is could see some decent storms. Second, this warm front will pull north into KY, leaving Middle TN in a moist, warm sector during the afternoon. Latest CAM guidance is suggesting it will be quiet and the environment will have an opportunity to warm and destabilize further for the evening activity. Let`s not get ahead of ourselves here. The afternoon is going to carry with it the potential for discrete supercell development. The bulk of this *should* remain southwest of Middle TN. However, there is the potential we could see some development or storms could develop to our southwest and move into our southwest counties (south of I-40 and west of I-65) during the afternoon. While confidence of this occurring is low, it does need to be monitored closely. Obviously, if this occurs, tornadoes, straight line winds and hail would be the main threat with any of these storms. Third, and this is the main show, storms along the cold front in the evening hours. Even if the afternoon stuff doesn`t occur, this is our best bet for severe weather for much of Middle TN -- and all modes: tornadoes, straight line winds, hail (less of a chance) and flash flooding. Main time frame is 7 pm until 2 am. Yes, 2 am. Latest guidance has slowed the approach of these storms, which could help things start later and linger later into the night for our eastern counties. Here`s the main takeaway from all of this: the bulk of this activity is at night, which means yet another nocturnal event in Middle TN. Please have multiple ways to get warnings (in case one way fails), have a plan in place to shelter in a hurry, if you go under a warning and third, you may even consider waiting until the storms pass you before going to bed Wednesday night. This might be more difficult east of I-65 as it`ll likely be later in the night before storms reach you, but it could be beneficial if pinched for time when you need to take shelter. The cold front associated with the overnight storms should have things off the Plateau before daybreak Thursday, however the rain is likely not to be over. The upper trough with this system could very well traverse Middle TN during the day on Thursday and provide an opportunity for thunderstorms Thursday afternoon. I don`t expect anything severe, but with the cold core of the upper low overhead on Thursday, some hail associated with these storms is not out of the question, especially east of I-65. By Friday, things will quiet down for awhile. The weekend will be dry and decent, but if you`re fan of the GFS, yet another system could be on tap this time next week (the Euro holds off until later in the week). It is March and we are in severe weather season, so if you haven`t done so already, take a minute this evening and visit ready.gov/plan. You can get some pointers on how to prepare yourself and your family BEFORE the storms get to you.

Day 3 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0234 AM CDT Tue Mar 16 2021 Valid 181200Z - 191200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS EXTENDING FROM GEORGIA NORTHWARD ACROSS THE CAROLINAS... CORRECTED TO INCLUDE SIG AREA IN PROB GRAPHIC ...SUMMARY... Severe weather is expected from southern Virginia southward into Florida, and westward into portions of eastern Kentucky/eastern Tennessee Thursday. Along with potential for hail and locally damaging winds, several tornadoes -- a couple of them possibly strong -- are anticipated. ...Synopsis... A vigorous upper low initially progged over eastern portions of the Ozarks, is expected to continue steady eastward progression through the period, weakening gradually as it crosses the Appalachians and reaches Virginia/the Carolinas by the end of the period. In the wake of this feature, ridging will expand to encompass much of the country, as an eastern Pacific trough nears the Pacific Northwest Coast late. As the upper system advances, a surface low just ahead of cyclone aloft will likewise progress eastward, crossing the mountains during the evening before redeveloping offshore through the end of the period. A trailing cold front will cross the southern Appalachians through the first half of the period, before moving offshore overnight. A second day of fairly widespread -- and possibly locally substantial -- severe risk is anticipated. ...Parts of the Mid and Southern Atlantic Coast states, and westward into eastern parts of KY/TN... Showers and thunderstorms -- and some attendant severe weather risk -- will be ongoing Thursday morning, particularly over the southern Appalachians region. With associated clouds streaming northeastward across the middle and southern Atlantic Coast states, hindered heating -- and thus tempered diurnal destabilization -- is expected. Still, with northward advection of higher theta-e air east of the mountains ahead of the advancing surface system causing a rapid retreat of the remnant damming front, sufficient CAPE should evolve to support vigorous storms -- with intensity of the updrafts aided by strongly veering/increasing flow with height. Storms should increase through midday west of the mountains across parts of eastern Kentucky/eastern Tennessee ahead of the synoptic system. Relatively low-topped storms -- and local risk for all-hazards severe weather -- will likely evolve. Meanwhile, storms are expected to spread across Georgia and into the Carolinas ahead of the advancing cold front, along with some pre-frontal cellular development within a zone of strong warm advection east of the mountains. Given ample instability and a very favorably sheared environment, relatively widespread and locally substantial severe weather potential is indicated -- including risk for a few strong tornadoes. Potential is expected to expand northward toward/into southern Virginia with time as the front retreats into the evening, before convection begins to end from west to east as the cold front moves toward -- and eventually off -- the Atlantic Coast. ..Goss.. 03/16/2021

Should be worth a thread Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1231 PM CDT Tue Mar 16 2021 Valid 171200Z - 181200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN ARKANSAS...NORTHEAST LOUISIANA...SOUTHWEST TENNESSEE AND MUCH OF MISSISSIPPI AND ALABAMA... ...SUMMARY... A regional outbreak of severe storms is expected Wednesday into Wednesday night across portions of the lower Mississippi Valley into Alabama. Widespread severe storms capable of producing tornadoes (several of which may be intense), very large hail and intense damaging wind gusts are expected. More than one round of severe storms are possible across parts of Mississippi into Alabama during the afternoon into the overnight hours. ...Synopsis... A compact and intense upper low over the southern Plains will eject eastward to the Ozark Plateau/lower MS Valley on Wednesday. A surface low centered over northeast OK will develop east/northeast in tandem with the upper system. At the beginning of the period, a cold front will extend southward from the low across eastern OK into eastern TX before arcing southwest into south TX. A warm front draped northwest to southeast from near the MO/AR border into northern AL will gradually lift northward through the period. There is some uncertainty in how far north this boundary will lift across northern GA/eastern TN given strong cold air damming across the Carolinas until very late in the period. The cold front should push eastward to Middle TN/central AL and the western FL Panhandle. Across the broad warm sector, dewpoints in the mid/upper 60s are expected beneath steepening lapse rates and intense vertical shear, resulting in an environment capable of supporting a widespread severe weather outbreak. ...Southern Plains to the Mid-MS Valley... Convection will be ongoing Wednesday morning near the surface low, southward along the cold front, and eastward along the northward retreating warm front from central AR into northern MS/AL. Any convection north of the warm front will be elevated and pose a threat mainly for large hail. However, shear profiles will improve through the morning and surface-based storms near the triple point and along the warm front are possible and will increase the risk for damaging gusts and a few tornadoes. Further south along the cold front across eastern OK into eastern TX, convection will move into an increasing unstable and moist environment. A line of supercells and line segments is expected to develop as convection moves into AR and approaches the Sabine Valley. All severe hazards are expected with this activity from Wednesday morning into the afternoon. ...Lower MS Valley into AL/GA... Multiple rounds of intense, severe convection will be possible, mainly across MS/AL on Wednesday afternoon into the overnight hours. Convection will intensify along the eastward progressing cold front across central and eastern AR/LA during the late morning/afternoon as it encounters effective shear greater than 60 kt, MLCAPE around 1500-2500 J/kg and midlevel lapse rates around 7-8 C/km. Fast storm motion, with 925-700 mb flow greater than 40 kt will support widespread damaging gusts with some gusts greater than 65 kt expected. Large hail (some greater than 2 inch in diameter, especially from the AR/MO border into northern LA, southwest TN and northern/central MS) is also expected with this activity. Further east across northeast LA into MS and AL a more concerning scenario appears possible. Most forecast guidance agrees that a round of afternoon thunderstorms are expected. This activity is expected to develop in weaker ascent, driven by heating and low level warm advection. Strong 0-3 km shear near 30-40 kt will already be in place with enlarged low level hodographs evident. Given weaker forcing, this activity will have an opportunity to remain more discrete and any cell will quickly become a supercell capable of producing strong tornadoes. As a 40-50 kt low level jet increases around 00-03z, intense supercells are expected to advance eastward along with the cold front across MS and into AL overnight. This will bring a second round of significant severe storms capable of intense tornadoes, large hail and intense damaging winds across much of MS/AL. If these trends are maintained, an upgrade to a High risk could be necessary with the initial Day 1 Convective Outlook at 06z tonight. ..Leitman.. 03/16/2021 CLICK TO GET WUUS02 PTSDY2 PRODUCT

correct,i was looking at 1999,thanks

As expected with the passing EKW,1+2 is warming up again.Subsurface has warmed some by the looks west of the IDL,didnt post the last update but it seems they now do adjustments every 3 or 4 days without doing the time stamp

Interestingly, no (E)F5 tornadoes were recorded in phases 3, 4, or 5 during the study period. Cross-phase variability explained by the GWO is substantial, and has not been demonstrated to this magnitude by other known teleconnection indices [e.g., the North Atlantic Oscillation (NAO)]. A robust example is shown when analyzing (E)F1+ tornadoes during strong GWO events. During GWO phases 1 and 2, statistically significant positive tornado count and average tornado count per day anomalies are found. In contrast, phases 4 and 5 revealed negative counts and negative tornado count per day anomalies at the 95% confidence level (Fig. 2). Odd how there has never been a violent EF5 with this study,while in 3,4 and 5.The Wayne and Lawrence County EF5 happened in a LaNina year and the GWO was in phase 6

Right,i just posted this to show the similarity to where the GWO is in phase 2 from this paper,it does not mean we can't get severe weather in Tn

Meant the put the link up,here it is https://journals.ametsoc.org/view/journals/mwre/144/2/mwr-d-15-0289.1.xml

GWO is in phase two today

Models keep showing a trough going through East Asia even into Korea next weekend,by far the best trough through that region it seems like in a couple months.PNA might be tilted more + but there also seems to be another EKW today getting into region 3 and a KW into NA into week 3 of March,seemingly around the 28th of March give or take might be our next shot of severe storms after this one upcoming right now

I'd be surprised if you dont see a slight risk upcoming,even with some timing differences the mid week system

Last four runs of the GFS,looks better today but still beyond it's belief time frame

Definite not seeing nothing consistent with the models

CFS is showing another EKW the next couple days getting into 1+2,the last one that went through a few days ago has warmed this region up pretty good recently.

Few more days before the upgrade to V16,unless something changes https://www.weather.gov/media/notification/scn_21-20_gfsv16.0_aaa_update.pdf

So what happens during a power outage?

Either CPC just forgot to change the date or a adjustment was made to the last update

I was playing with my new toy above. CFS looks active in the Pacific upcoming.Sure this will change some but the models will probably struggle with the upcoming pattern.GFS is already trying to hint at bulding another Sub-Tropical ridge into the GOM.But this time frame should be our best shot upcoming at some possible severe weather.

1.mp4

SPC today almost shows a basin wide moderate NINA,but the SOI is acting like this is a more ELNino the last few days,been awhile since it went negative,the SOI

https://www.spc.noaa.gov/exper/archive/event.php?date=20210228 Fatality in Ga

Talk about a lucky young man https://wreg.com/news/child-shocked-by-power-line-in-nashville-while-playing-barefoot-in-rain/

URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 15 NWS Storm Prediction Center Norman OK 810 PM EST Sun Feb 28 2021 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Far south-central Kentucky Middle Tennessee * Effective this Sunday evening from 810 PM until 1100 PM EST. * Primary threats include... Scattered damaging wind gusts to 70 mph possible A tornado or two possible SUMMARY...Cluster of strong to severe storms may produce damaging winds and a brief tornado before it weakens later this evening. The severe thunderstorm watch area is approximately along and 40 statute miles north and south of a line from 80 miles west of Crossville TN to 20 miles northeast of Crossville TN. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU5).