jaxjagman

Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0222 AM CST Thu Feb 21 2019 Valid 231200Z - 241200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS SATURDAY THROUGH SATURDAY EVENING ACROSS PARTS OF CENTRAL/EASTERN ARKANSAS...THE MISSOURI BOOTHEEL...WESTERN/CENTRAL KENTUCKY...WESTERN/MIDDLE TENNESSEE...NORTHERN MISSISSIPPI AND NORTHWESTERN ALABAMA... ...SUMMARY... An organized cluster of severe thunderstorms may evolve Saturday in a corridor across the Ozark Plateau through the lower Ohio Valley, with additional severe storms possible across the lower Mississippi into Tennessee Valleys. Considerable wind damage may accompany these storms along with the risk for tornadoes, some of which could be strong. ...Discussion... In phase with the subtropical westerlies, a vigorous short wave impulse of mid-latitude Pacific origins is forecast to accelerate northeast of the southern Plains through the Great Lakes region during this period. Strong cyclogenesis may already be underway by 12Z Saturday near the Texas/Oklahoma Panhandle vicinity, and models continue to indicate that the rapid evolution of a broad and deep cyclone will proceed northeastward into the Great Lakes region by the end of the period. This likely will include the intensification of a cyclonic mid-level jet, including speeds in excess of 100 kt at 500 mb, across the southern Plains Red River Valley, through the middle Mississippi and Ohio Valleys. Across the evolving warm sector, models indicate that south/southwesterly winds will strengthen to 50-70+ kt through the 850-700 mb layer. Although the warm frontal zone probably will surge north of the Ohio River, and into/through the lower Great Lakes region by late Saturday evening, an initial position roughly along the Ohio River west-southwestward into the Ozark Plateau may provide the main focus for severe thunderstorm potential. Early period convection, associated with weak elevated destabilization above the front, may inhibit, or at least slow, boundary-layer destabilization to the north, while leaving a remnant surface boundary. In association with the onset of stronger surface pressure falls, surface dew points are expected to increase through the lower/mid 60s along and south of this boundary. Coupled with strengthening large-scale ascent, this is expected to contribute at least weak boundary-layer destabilization supportive of an evolving organized mesoscale convective system. CAPE on the order of 500+ J/kg appears possible. Given the strength of the environmental wind fields (and shear) within the convective layer, the convective system may be accompanied by considerable potential for strong and damaging wind gusts. It appears that this may initiate over parts of central and eastern Arkansas by midday, before progressing east-northeastward through the lower Ohio Valley by Saturday evening. A few tornadoes, some strong, are also possible, particularly with discrete supercells which may form near/just ahead of mainly the southern flank of the evolving system. More discrete storms, including supercells, may eventually develop as far south as the lower Mississippi Valley through portions of the southern Appalachians by late Saturday night.

Excessive Rainfall Discussion NWS Weather Prediction Center College Park MD 326 PM EST Wed Feb 20 2019 Day 3 Valid 12Z Fri Feb 22 2019 - 12Z Sat Feb 23 2019 ...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PARTS OF THE LOWER MISSISSIPPI VALLEY TO THE TENNESSEE VALLEY... ...Southern U.S. to parts of the Southeast U.S. and southern Appalachians... The frontal boundary that will provide focus for convection on Day 2 will slowly lift northward on Day 3--in fact it is expected to be quasi-stationary until the surface low ejects into the southern Plains and lifts the front northward by the end of Day 3. Broad southwest to northeast flow aloft at the jet-stream level is expected along with channeled vorticity at the mid-levels. This is not the best set up for a focus on heavy rainfall and models still have spread where the heavy rainfall axis will be. For now, the QPF is placed just to the south and east of where the lower FFG values are. Because confidence is still low in this axis placement, continued the Slight Risk of excessive rainfall--and based on where the models begin to have more consensus and what happens over the next few days, this could warrant an upgrade in the future.

Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CST Wed Feb 20 2019 Valid 231200Z - 281200Z ...DISCUSSION... Medium-range model output continues to indicate strong cyclogenesis will commence across the southern Plains by 12Z Saturday, before continuing northeastward through the Great Lakes region by 12Z Sunday. Guidance indicates that the rapid evolution of a broad and deep cyclone is likely, aided by a vigorous short wave impulse emerging from the Southwest. It appears that this will be accompanied by an intensifying cyclonic mid-level jet, including in excess of 100 kt at 500 mb by midday Saturday across the southern Plains Red River Valley, and 50-80+ kt south/southwesterly 850-700 mb flow across the destabilizing warm sector. This environment may become conducive to the evolution of a significant organized mesoscale convective system, potentially accompanied by considerable damaging wind gusts. Highest severe probabilities appear focused in a swath across parts of the Ozark Plateau and lower Mississippi Valley into the Tennessee and lower Ohio Valleys. A warm front may initially be located along a corridor near or just south of the Ohio River, west southwestward into northwestern Arkansas, near the northern periphery of the currently depicted 15 percent severe probabilities. While the influence of current snow and ice cover near and northwest of this region remains uncertain, this boundary may ultimately remain the focus for the track of the northern flank of an evolving squall line. However, based on the track of the low, aided by strong dynamic forcing, destabilization supportive of severe thunderstorm potential could develop northward into southern portions of the Great Lakes region Saturday night. The southern edge of the 15 percent probabilities is based on the model consensus of the southern periphery of the deeper surface cyclone. The southern flank of an evolving squall line may extend this far south, where boundary-layer moistening and destabilization will likely be most favorable. This environment may also support discrete supercell development in advance of the squall line. In addition to the risk for damaging convective gusts, there appears potential for tornadoes, including some strong.

Flood Watch National Weather Service Nashville TN 930 PM CST Tue Feb 19 2019 ...Flash Flood Watch in effect through early Thursday morning across Middle Tennessee... .Rain will continue through tonight and into Wednesday as a warm front lifts northward from the Gulf Coast. Rain will be heavy at times tonight and into tomorrow. Due to the saturated ground from previous rainfall, this additional heavy rain could lead to flash flooding. TNZ005>011-023>034-056>066-075-077>080-093>095-201200- /O.CON.KOHX.FF.A.0002.000000T0000Z-190221T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Stewart-Montgomery-Robertson-Sumner-Macon-Clay-Pickett-Houston- Humphreys-Dickson-Cheatham-Davidson-Wilson-Trousdale-Smith- Jackson-Putnam-Overton-Fentress-Perry-Hickman-Lewis-Williamson- Maury-Marshall-Rutherford-Cannon-De Kalb-White-Cumberland-Bedford- Coffee-Warren-Grundy-Van Buren-Wayne-Lawrence-Giles- Including the cities of Dover, Clarksville, Springfield, Hendersonville, Gallatin, Goodlettsville, Lafayette, Celina, Byrdstown, Erin, Waverly, New Johnsonville, McEwen, Dickson, Ashland City, Kingston Springs, Nashville, Lebanon, Mount Juliet, Hartsville, Carthage, South Carthage, Gordonsville, Gainesboro, Cookeville, Livingston, Jamestown, Allardt, Linden, Lobelville, Centerville, Hohenwald, Franklin, Brentwood, Columbia, Lewisburg, Murfreesboro, Smyrna, La Vergne, Woodbury, Smithville, Sparta, Crossville, Shelbyville, Tullahoma, Manchester, McMinnville, Altamont, Coalmont, Spencer, Clifton, Waynesboro, Lawrenceburg, and Pulaski 930 PM CST Tue Feb 19 2019 ...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH LATE WEDNESDAY NIGHT... The Flash Flood Watch continues for * A portion of Middle Tennessee, including the following areas, Bedford, Cannon, Cheatham, Clay, Coffee, Cumberland, Davidson, De Kalb, Dickson, Fentress, Giles, Grundy, Hickman, Houston, Humphreys, Jackson, Lawrence, Lewis, Macon, Marshall, Maury, Montgomery, Overton, Perry, Pickett, Putnam, Robertson, Rutherford, Smith, Stewart, Sumner, Trousdale, Van Buren, Warren, Wayne, White, Williamson, and Wilson. * Through late Wednesday night * 1.5 to 3 inches of rainfall are expected across the watch area.

esoscale Precipitation Discussion 0052 NWS Weather Prediction Center College Park MD 403 PM EST Tue Feb 19 2019 Areas affected...Along the southern Tennessee border Concerning...Heavy rainfall...Flash flooding possible Valid 192102Z - 200202Z Summary...Repeating thunderstorms with three-hourly rainfall rates up to 2 inches will continue a risk of flash flooding into this evening south from the southern TN border. A low level boundary has set up across northern MS/AL/GA this afternoon where Gulf moisture is converging. Regional radars depict a broken line of moderate to heavy thunderstorms from southern AR to northern GA with up to moderate stratiform rain farther north along the TN border. The thunderstorms are shifting northeast from deep layer southwesterly flow with upwind propagation vectors directed east. GOES-16 Clean-IR depicts some cooling tops for the activity moving from AL to GA as well as a cluster shifting north over central MS. Observed precipitable water (PW) values between 1.2 and 1.4 inches across interior sections of the southeast late this afternoon are around two standard deviations above normal. The highest observed three-hour rain rates have been around 1.5 inches this afternoon from gauges in north-central MS and over the Atlanta Metro. This heaviest rain has been on the northern end of instability with MUCAPE of 100 to 250 J/Kg where thunderstorms have repeated in short intervals. 850mb southerly flow of 35 to 50 kt is converging on the low level boundary and slowly pushing it north. The latest global and hi-res guidance brings this boundary north across the TN border into the evening. Three-hour flash flood guidance is generally around 2 inches across this area. Localized areas in the heaviest thunderstorms could have rainfall exceed these values and cause flash flooding into this evening.

Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0357 AM CST Tue Feb 19 2019 Valid 221200Z - 271200Z ...DISCUSSION... Medium-range models suggest that blocking will become more prominent at a higher latitude of the northeastern Pacific this coming weekend through early next week. As this occurs, split downstream westerlies will generally converge inland of the Pacific coast, with the southern mid-latitude and subtropical westerlies generally decreasing in amplitude across the southern tier of the United States. Prior to this transition, at least one more vigorous short wave impulse is forecast to emerge from persistent larger-scale western U.S. troughing late this week, as a significant upstream perturbation digs into the U.S. Pacific Northwest. Latest model output remains similar to prior runs indicating that the lead impulse will support strong cyclogenesis to the lee of the Rockies, likely from the Texas/Oklahoma Panhandle vicinity through the Great Lakes on Saturday. It still appears probable that there will be sufficient boundary layer moisture return across the evolving warm sector to contribute to weak to modest destabilization in the presence of intensifying wind fields (including 50-70+ kt in the 850-500 mb layer), from portions of the lower southern Plains and Ozark Plateau through portions of the lower Mississippi and Ohio Valleys. Forcing for ascent may support the evolution of a mesoscale convective system capable of producing damaging wind gusts. This could be preceded by discrete supercell development and an associated risk for tornadoes. Although more uncertain, it is possible that severe weather potential could continue eastward into portions of the Allegheny and Cumberland Plateaus by late Saturday night. Uncertainty concerning this potential increases further for Sunday, eastward and southeastward across the Mid Atlantic and Southeast.

For the time being the more severe into March would be more mainly into the S/Plains,doesn't mean we can't get any severe,it's with what the CFS is showing right now

National Weather Service Nashville TN 533 AM CST Sun Feb 17 2019 .UPDATE... FOR 12Z AVIATION DISCUSSION. && .DISCUSSION... ...Heavy Rainfall and Flooding Likely This Week... A very wet pattern will be in place this week with several rounds of rainfall, heavy at times. Our latest total QPF through the next 7 days ranges from 5 to 10 inches of rainfall in Middle Tennessee. The biggest problem is exactly where the heavier amounts will occur. Each wave that moves across the area could set up a narrow axis of especially heavy rainfall, and the position of each could vary significantly or could repeatedly focus over one area. Models are varying with qpf axis, so it is important that we not focus on just one area for flooding potential. The pattern and expected rainfall will present a threat for flooding across the entire Mid State. This includes flooding of streets, low lying and flood-prone areas, streams, and the major rivers. Scattered showers and a few rumbles of thunder were ongoing at 3 AM CST. We expect a this wave of showers and isolated thunderstorms to move across the area this morning with one tenth to one half inch of rainfall, then a second wave this afternoon and evening will impact mainly the southeast half of the area with another quarter to half inch. Other than brief ponding on roads, there should not be any flood problems today. Temperatures will warm into the 50s. Showers will taper off tonight with a dry day Monday- probably the only dry day this week. For Tuesday through Wednesday, a big system will move slowly out of the Southern Rockies, setting up deep southwest flow into Tn and surrounding states. This flow will bring in upper level tropical moisture and a series of disturbances. The Gulf of Mexico will open up with development of a 40-50KT LLJ transporting abundant low level moisture directly to the Tn Valley. A surface trough will set up over Mid Tn, becoming a focus for potentially excessive rainfall. Repeated episodes of heavy rainfall are likely from late Tuesday through Wednesday with the upper flow being parallel to the low level trough axis. The rainfall intensity may ease up a bit for Thursday and Friday, then models show another surge of heavy rainfall by next weekend. Too soon for any watches today- we will continue with a Hydrologic Outlook (ESF) and heavy rain / flood potential messaging through social media. We ask local media to place emphasis on the hydro message - possible major flooding- for the entire area.

Jamstec is showing an developing LaNina into fall.This should be updated and O-N-D.Possibly an early winter season what it shows depending on any SSWE or how strong it gets

Not sure about 10".But i'm going by the Euro and not GFS.There's more convection shown.Also the DP depression would most certainly be fog and rain . 12Z FEB16 2 M SFC SFC 6 HR 6 HR 6 HR 500 1000 TMP DEW CAPE QPF CVP NCP HGT 500 (C) (C) J/KG (IN) (IN) (IN) (DM) THK SAT 12Z 16-FEB 5.9 5.4 1 561 553 SAT 18Z 16-FEB 11.1 4.7 1 0.00 0.00 0.00 564 555 SUN 00Z 17-FEB 8.8 5.0 0 0.00 0.00 0.00 565 556 SUN 06Z 17-FEB 6.3 4.2 13 0.01 0.00 0.00 566 557 SUN 12Z 17-FEB 8.4 7.9 16 0.16 0.13 0.03 567 558 SUN 18Z 17-FEB 11.7 10.8 21 0.08 0.01 0.06 569 560 MON 00Z 18-FEB 12.0 11.9 120 0.13 0.04 0.09 570 562 MON 06Z 18-FEB 10.7 10.6 17 0.71 0.15 0.56 570 559 MON 12Z 18-FEB 4.4 3.8 0 0.15 0.06 0.09 569 553 MON 18Z 18-FEB 11.3 -0.3 0 0.00 0.00 0.00 572 552 TUE 00Z 19-FEB 6.9 -2.2 0 0.00 0.00 0.00 574 553 TUE 06Z 19-FEB 2.2 -2.8 0 0.00 0.00 0.00 577 552 TUE 12Z 19-FEB 1.3 -3.7 0 0.00 0.00 0.00 577 551 TUE 18Z 19-FEB 5.3 1.8 0 0.07 0.05 0.02 579 554 WED 00Z 20-FEB 3.9 3.8 13 0.52 0.18 0.34 579 556 WED 06Z 20-FEB 4.5 3.6 121 0.36 0.20 0.16 579 561 WED 12Z 20-FEB 5.7 4.8 4 0.06 0.02 0.04 579 562 WED 18Z 20-FEB 10.4 8.5 128 0.10 0.07 0.03 579 564 THU 00Z 21-FEB 9.7 9.6 326 0.50 0.38 0.13 578 565 THU 06Z 21-FEB 11.5 11.5 526 0.48 0.38 0.09 577 565 THU 12Z 21-FEB 12.3 12.1 233 0.54 0.37 0.17 576 564 THU 18Z 21-FEB 14.0 13.4 238 0.24 0.11 0.13 576 563 FRI 00Z 22-FEB 9.5 9.0 38 0.58 0.32 0.26 576 561 FRI 06Z 22-FEB 7.9 7.4 1 0.14 0.05 0.09 577 561 FRI 12Z 22-FEB 8.0 7.6 1 0.05 0.01 0.04 577 560 FRI 18Z 22-FEB 9.7 9.6 144 0.25 0.09 0.16 579 561 SAT 00Z 23-FEB 10.2 10.1 407 0.39 0.24 0.15 579 562 SAT 06Z 23-FEB 12.4 12.4 430 0.40 0.30 0.10 579 562 SAT 12Z 23-FEB 12.3 11.9 80 0.26 0.23 0.03 579 563 SAT 18Z 23-FEB 17.2 14.9 181 0.04 0.02 0.02 578 564 SUN 00Z 24-FEB 16.6 15.6 194 0.06 0.04 0.02 576 565 SUN 06Z 24-FEB 16.7 16.7 310 0.35 0.07 0.28 571 564 SUN 12Z 24-FEB 9.4 2.7 0 0.28 0.05 0.24 568 556 SUN 18Z 24-FEB 7.1 -7.1 0 0.00 0.00 0.00 565 547 MON 00Z 25-FEB 4.2 -7.2 0 0.00 0.00 0.00 566 547 MON 06Z 25-FEB 0.2 -7.6 0 0.00 0.00 0.00 567 546 MON 12Z 25-FEB -2.0 -8.6 0 0.00 0.00 0.00 567 546 MON 18Z 25-FEB 6.9 -8.8 0 0.00 0.00 0.00 568 546 TUE 00Z 26-FEB 5.7 -3.2 0 0.00 0.00 0.00 566 547 TUE 06Z 26-FEB 2.1 -4.5 0 0.00 0.00 0.00 566 546 TUE 12Z 26-FEB -1.2 -6.4 0 0.00 0.00 0.00 566 544

Hydrologic Outlook Hydrologic Outlook TNC003-015-021-027-031-035-037-041-043-049-055-061-081-083-085- 087-099-101-111-117-119-125-133-135-137-141-147-149-159-161-165- 169-175-177-181-185-187-189-172045- Hydrologic Outlook National Weather Service Nashville TN 234 PM CST Sat Feb 16 2019 ...More heavy rain and flooding possible across Middle Tennessee next week... A very active weather pattern is expected to continue affecting Middle Tennessee through next week into the following weekend, with frequent storm systems bringing rain almost every single day. The next round of rain will arrive tonight and continue into Sunday night. After another brief drying out on Monday, particularly heavy rain is forecast from Tuesday through Thursday of next week, and even more heavy rain is possible next weekend. Although the forecast remains uncertain on which parts of Middle Tennessee may see the heaviest rainfall next week, current indications are that total rainfall amounts could reach anywhere from 3 inches northwest to 9 inches southeast. Due to the frequent and well-above normal rainfall that has already fallen across Middle Tennessee this month, grounds are saturated and many rivers, creeks and streams are already running high. The forecast heavy rainfall over the next week has the potential to cause significant flooding along area rivers, with flooding of some area roadways, low lying areas, and other poor drainage locations also possible. Residents across Middle Tennessee should continue to closely monitor the potential for heavy rainfall and flooding next week. For the latest forecast updates and river forecasts, visit our website at weather.gov/nashville.

Early season i agree.Some chance of thunderstorms next week as a WF lifts into the lower OV putting the Valley in the warm sector,then a CF comes through.CIPS and even the dashboard hints at thunderstorms.Wouldn't mind tho seeing a good light show at night time

We'll see

Really starting to like down the road for some potential severe risk.Synoptic pattern looking at the Upper plains has shown some severe outbreaks in the SE.The NMME and even the RRWT shows this pattern into the spring time.The NMME and RRWT warm temps into April off the Japan coast down into maybe north of the Sea of the Philippines.This would set up a more of a east coast ridge if it were to teleconnect right.This isn't a forecast,just my presumption at this point. http://www.shawnmilrad.com/severe/

I'll post this here since flooding is severe.There really looks like some parts of the Valley will break records for the most rain fall in the month of Feb.Nashville's record was set in 1989 with 10.12".So far Nashville has 4.37".Not sure about the other areas if i get time i will explore more.Memphis broke the record last year with over 11" for Feb that was set back in 1948

NMME is showing the ENSO going neutral in the summer time.Also what looks to be the strongest WWB of the season east of the IDL could happen upcoming.

Two weak tornadoes confirmed today from yesterday's storms https://forecast.weather.gov/product.php?site=NWS&issuedby=OHX&product=PNS&format=CI&version=1&glossary=1

We havent heard thunder here in months.

Day 1 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0714 AM CST Wed Feb 06 2019 Valid 061300Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SOUTHERN OK/NORTH TX TO WESTERN KY/TN... CORRECTED FOR DAY OF THE WEEK ...SUMMARY... Episodic severe storms will be possible from parts of the southern Great Plains into the Tennessee and Lower Ohio Valleys, mainly from late afternoon through tonight. ...Southern Great Plains to TN/Lower OH Valleys... A messy, relatively low confidence scenario for severe storms is apparent this afternoon through tonight, resulting in maintenance of risk area shape but with an overall southward shift. Have decreased wind/tor probabilities across the northern portion of the risk areas where the polar air mass is likely to remain entrenched. Have increased hail probabilities in magnitude and spatially given the expectation of at least a few supercells this afternoon/evening and for the incipient stage of storm development tonight in the southern Great Plains. The surface front has remained nearly stationary in an arc across northwest TX and far southeast OK, with the portion across AR/MO still sinking south with weak cold advection behind it. This boundary should fully stall by midday with some drift back to the northwest as cyclogenesis occurs in the lee of the southern Rockies. A series of cyclones should develop southeast along the front across the TX Panhandle into far south-central OK through tonight, before consolidating near the AR/MO border by 12Z Thursday. Isentropic ascent/warm advection near the boundary along with weak boundary-layer heating of a warm sector characterized by mid 60s surface dew points should promote scattered thunderstorms along and north of the front through early evening in an arc from southeast OK to TN/KY. While elongated hodographs should support a few embedded supercell structures later today, seasonably modest low-level winds and mid-level lapse rates may curtail a more robust tornado and severe threat. Along the western portion of the warm sector in central TX to far south-central OK, the 10Z HRRR is an outlier with the depiction of intense supercell development near/north of the triple-point region along the Red River. This scenario while seemingly unlikely is possible given strengthening convergence associated with cyclogenesis. Should this occur and a discrete cell or two are able to deviate along the boundary, wind profiles would be highly favorable for a large hail and tornado threat. While other CAMs do not support this scenario, as mid-level height falls finally begin to overspread the region, scattered convection should develop generally on the cool side of the boundary in OK tonight and eventually southward along the developing cold front/remnant dryline into north-central TX. Clusters evolving into broader line segments appear probable overnight as forcing for ascent intensifies, but a strong cap should largely inhibit open warm-sector storm development. In addition, the southern extent of storms should struggle given the track of the shortwave trough from the southern Rockies towards the MO Valley. Still, strengthening low/deep-layer shear could sustain an isolated severe risk overnight.

Short range models are showing some better instability tomorrow for the Valley,we'll see where it goes from here

The KI,cape,shear is a good tool(at a starting point),but other indices are involved with the severe thunderstorm aspect and some indices rely with other indices for severe storms.If you want to learn more about severe this is a good starting spot . http://www.theweatherprediction.com/severe/indices/

Trough is showing further back to the west and the heights are rising up.Best shot of any thunderstorms right now looks to be Wed.afternoon into the the early evening,going by the Euro.Not as much rain also with this look.

Timing differences which should not surprise anyone.CIPS is now showing a chance of thunderstorms.Besides from t-storms the Euro would be a decent rain maker with what it shows with LLShear around 30-35kts and a LLJet 45-50 kts coming through,could be 1.5" to 2" of rn as of today which would be more Tuesday into Wed.

Possibly some strong storms next Sunday/Monday,to far out right now to tell but both the GFS AND Euro are showing the DP'S into the lower 60's,with instabilities showing.