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janetjanet998

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  1. they have cut back on flows from Cumberland. now down to 25,000 cfs from 29K...will be interesting to see if they increase again once the first slug of precip passes lake level as of 4pm 740.22. for some reason the river gauge on the NWS site is below the TVA gauge ...the TVA page updates in batches and is delayed but you can see the 15 min rises on the NWS river gauge in real time (hr delay) under tabular data not much news out of TVA or the media about the lake level....internet rumblings and rumors last weekend said the Corp expects tto hit 745...but that was before the higher then expected rain that fell over the weekend I can tell you it its going to go higher then 745....epsecially if any training sets up over the watershed.. DWR( CA version of TVA) was always behind the curve on Dduring Oroville and said it wouldn't go over the emergency spillway when it was obvious it was.. DWR calculates inflow into their lakes but taking the known out flow and the change in lake level per hour using a known chart....TVA doesn't do that to at least doesn't makes it public
  2. Lake Cumberland 740.08 and still rising without any new rain I hope they reset the radars total storm totals after the bright banding is over..I forsee people on social media sites pointed out the inflated amounts flash flood warnings north central MS.... for some reason they didn't increase the OH river crests today/// it's nowcast time....I suspect the front will get hung up more then modeled KMSL already over 3/4 on an inch already
  3. 12z models so far keep the training storms along and west of the MS river out of the TVA system the first event,,but NAMS sometimes too far NW NOTE: radars will likely be bright branded at the beginning of this event so precip amounts will be overdone the further you get from the radar site EXCESSIVE RAINFALL DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 948 AM EST TUE FEB 19 2019 DAY 1 VALID 15Z TUE FEB 19 2019 - 12Z WED FEB 20 2019 1500 UTC UPDATE NO CHANGES MADE TO THE PREVIOUS EXCESSIVE RAINFALL OUTLOOK. ORAVEC ...A MODERATE RISK OF EXCESSIVE RAINFALL EXISTS BETWEEN THE ARKLATEX AND SOUTHWEST KENTUCKY... LOWER MS VALLEY/SOUTHEAST/MID-SOUTH/OHIO VALLEY... THE LARGE SCALE SYNOPTIC PATTERN SHOWS MOISTURE SURGING NORTH OUT OF THE GULF OF MEXICO NORTH ON AN 850 MB JET OF 50-70 KTS, WHICH ADVECTS A PLUME OF PRECIPITABLE WATER VALUE OF 1.5-1.75" NORTH ACROSS LA INTO SOUTHEAST AR AND ADJACENT MS AS A SURFACE LOW MOVES IN FROM THE SOUTHWEST. ASCENT IS AIDED BY INCREASING DIFLUENCE/DIVERGENCE ALOFT AS THE APPROACHING UPPER LEVEL TROUGH AMPLIFIES. THE RESULT WILL BE INCREASING AREAL COVERAGE AND INCREASING RAINFALL RATES IN THIS AREA. BASED ON THE 18Z & 00Z GFS GUIDANCE, INTEGRATED VAPOR TRANSPORT (IVT) ECLIPSES 1000 KG/(M*S), WITH ITS NARROWNESS INDICATING THAT THE MOISTURE PLUME QUALIFIES AS AN ATMOSPHERIC RIVER AFTER 00Z WEDNESDAY/TUESDAY EVENING. THE MEAN FLOW BECOMES INCREASINGLY UNIDIRECTIONAL OUT OF THE SOUTHWEST, WHICH INCREASINGLY FAVORS CELL TRAINING WITH TIME. EFFECTIVE BULK SHEAR RISES TO 60-80 KNOTS. MESOCYCLONES ARE EXPECTED, BUT THE INGREDIENTS AVAILABLE INCREASINGLY FAVOR A CONVECTIVE MODE MORE ALONG THE LINES OF A COLD TROUGH SQUALL LINE ONCE THE 850 HPA FLOW STARTS TO VEER TOWARDS WEDNESDAY MORNING CLOSER TO THE GULF COAST WITHIN THE SURFACE LOW'S WARM SECTOR, WHICH SHOULD LIMIT OVERALL TOTALS ACROSS SOUTHERN LA AND SOUTHERN MS, WHERE A LESSER EXCESSIVE RAINFALL RISK HAS BEEN INDICATED. A TOTAL OF 3-4" APPEARS TO BE THE MOST LIKELY AREAL AVERAGE AMOUNTS, WITH LOCALLY HIGHER AMOUNTS IN THE 5-6" RANGE POSSIBLE PER THE MODEST SIGNAL SEEN IN THE 00Z MESOSCALE GUIDANCE. IN NORTHERN LA, NORTHERN MS, EASTERN AR, AND TN, HOURLY TOTALS IN THE 1-2" RANGE SHOULD BE POSSIBLE GIVEN THE MOISTURE AND INSTABILITY FORECAST (DESPITE THE 00Z HREF PROBABILITIES INDICATING LOWER). THIS, ALONG WITH TWO WEEK PRECIPITATION OF 300-500% OF AVERAGE SOMEWHAT FARTHER NORTH ACROSS PORTIONS OF AR, TN, KY, AND THE OH VALLEY RESULTED IN MAINTAINING THE MODERATE RISK AREA FROM CONTINUITY WITH COSMETIC CHANGES. THE MODELS CONTINUE TO SHOW SPREAD IN REGARDS TO THE QPF IN GENERAL WITH THE 00Z NAM THE FARTHEST NORTHWEST -- AS USUAL -- WHILE THE 00Z CANADIAN REGIONAL, 00Z ECMWF TO SOME DEGREE, AND 18/00Z GEFS-BASED QPF REFORECAST WERE MORE EASTWARD. WHEN ADJUSTMENTS WERE MADE CONCERNING WHERE THE BEST LOW-LEVEL CONVERGENCE AND INSTABILITY GRADIENT WERE EXPECTED, THIS BROADENED THE HEAVY RAINFALL FOOTPRINT FROM CONTINUITY EASTWARD TOWARDS THE CANADIAN REGIONAL AND QPF REFORECAST. THE INSTABILITY GRADIENT IS EXPECTED TO SHIFT FROM THE DEEP SOUTH INTO TN WITH TIME, WHICH IS WHERE THE HIGHEST HOURLY RAIN TOTALS ARE EXPECTED. TO THE NORTH AND NORTHEAST, RAINFALL SHOULD BE OF LONGER DURATION DUE TO MORE LIMITED INSTABILITY WITH HOURLY TOTALS CLOSER TO THE 0.5" RANGE SO DID NOT ALLOW THE MODERATE RISK AREA TO SHIFT VERY FAR INTO KY. COORDINATED WITH THE WINTER WEATHER FORECASTER TO ATTEMPT TO DELIMIT THE NORTHEAST PORTION OF THE MARGINAL AND SLIGHT RISK AREAS. ROTH DAY 2 VALID 12Z WED FEB 20 2019 - 12Z THU FEB 21 2019 ...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF THE SOUTHERN U.S. AND TENNESSEE/OHIO VALLEYS WEDNESDAY TO THURSDAY MOTNING... ....THERE IS A SLIGHT RISK OF EXCESSIVE RAIFNALL FROM THE TENNESSEE VALLEY INTO THE OHIO VALLEY... ..SOUTH AND SOUTHEAST U.S. INTO THE TN/OH VALLEY A HEAVY RAINFALL EVENT SHOULD BE ON-GOING AT THE BEGINNING OF THE DAY 2 FORECAST PERIOD, AIDED BY A WELL DEFINED MOSITURE PLUME COMING OFF THE GULF OF MEXICO...GOOD MID-LEVEL FORCING AND A STRONG UPPER LEVEL JET. MAINTAINED THE ON-GOING MODERATE RISK AREA IN PARTS OF ALABAMA WHERE THERE LOOKS TO BE THE BEST OVERLAP OF RAINFALL AMOUNTS IN THE DAY 1 AND DAY 2 PERIOD. RAINFALL AMOUNTS ARE FORECAST TO BE LESS THAN ON DAY 1, WITH MOST AREAS UNDER 2 INCHES. THE SLIGHT TO MODERATE RISK THAT REMAINS IN EFFECT REFLECTS THE HIGHER GROUND MOISTURE CONTENT AND REDUCED FLASH FLOOD GUIDANCE VALUES IN THE CENTRAL TO SOUTHERN APPALACHIANS AND ADJACENT VALLEY AREAS OF EASTERN KENTUCKY AND TENNESSEE. THE MODERATE RISK REMAINED WHERE OVERLAP OF HIGHER QPF OCCURS, BUT THE INCREASE IN FLASH FLOOD GUIDANCE VALUES FURTHER SOUTH IN BOTH MS/AL LEADS TO ONLY A SLIGHT RISK DESPITE SIMILAR RAINFALL TOTALS TO NORTHERN AL. LATER UPDATES MAY BE MADE AS RAINFALL TOTALS ADJUST, BUT ALSO CHANGES IN FLASH FLOOD GUIDANCE DUE TO PRIOR RAINS OCCURRING BETWEEN NOW AND THIS OUTLOOK PERIOD. BANN DAY 3 VALID 12Z THU FEB 21 2019 - 12Z FRI FEB 22 2019 ...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PARTS OF THE SOUTHERN U.S. ON THURSDAY INTO EARLY FRIDAY... ..SOUTHERN U.S. AFTER A BRIEF LULL, MORE MOISTURE WITH INCREASING COVERAGE OF RAINFALL BEGINS TO MOVE OFF THE GULF OF MEXICO INTO PARTS OF LOUISIANA, ARKANSAS AND MISSISSIPPI...MAINLY THURSDAY NIGHT AND EARLY FRIDAY. HIGH PRESSURE TO THE NORTH WILL INITIALLY LEAD TO DECREASING COVERAGE OF RAINFALL ACROSS THE SOUTHEAST U.S. DURING THE DAY ON THURSDAY. WITH MAXIMUM VALUE OF PRECIPITABLE WATER BEING 1.4 TO 1.5 INCHES EARLY IN THE EVENT AND A FEED OF COOLER/DRIER/MORE STABLE AIR COMING IN FROM THE NORTH, RAINFALL RATES AND COVERAGE OF RAINFALL SHOULD BE WANING EARLY. BY THURSDAY AFTERNOON, THOUGH, THE LOW LEVEL FLOW BACKS AND BEGINS TO ACCELERATE OFF THE GULF OF MEXICO IN RESPONSE TO AN AREA OF LOW PRESSURE EJECTING OUT OF THE ROCKIES. THE 00Z SUITE OF NUMERICAL GUIDANCE SHOWED DIFFERING SOLUTIONS AS TO HOW QUICKLY IT TAKES TO INITIATE ANOTHER ROUND OF CONVECTION CAPABLE OF PRODUCING HEAVY TO EXCESSIVE RAINFALL...BUT THE CONSENSUS AT THIS POINT APPEARS TO BE AFTER 22/00Z WHEN ISENTROPIC LIFT IN THE 300K TO 310K LEVELS INCREASES. PRECIPITABLE WATER VALUES OVER LA/AR/MS RECOVER AND SHOULD RANGE BETWEEN 1.5 AND 1.7 INCHES BY 22/12Z. THIS SHOULD BE SUFFICIENT TO FOCUS AND SUSTAIN RAINFALL RATES HIGH ENOUGH FOR FLASH FLOODING. THERE WAS SOME DEBATE OVER THE NEED FOR A MODERATE RISK AREA...BUT FELT THERE WAS ENOUGH UNCERTAINTY IN THE GUIDANCE (BOTH IN TERMS OF TIMING AND PLACEMENT) TO REMAIN WITH A SLIGHT RISK AREA DESPITE THE ANTECEDENT CONDITIONS. AN UPGRADE TO A MODERATE CAN STILL BE MADE IF NEEDED. SINCE THE NEXT PHASE OF THIS HEAVY RAINFALL EVENT IS EXPECTED TO CONTINUE INTO FRIDAY AND BEYOND, REFER TO FORECASTS AND DISCUSSIONS PREPARED BY THE WPC MEDIUM RANGE SECTION FOR ADDITIONAL INFORMATION.
  4. well with light rain moving into the southern TVA area..lets call the event started....it may rain continuously somewhere in watershed (TVA/OH) the whole week.....best chance for a break in between systems on Thursday as the firehose weakens and heads south before the next wave lake Cumberland as of 10pm last night 739.52 should hit 740 this morning..record 751.7ish. 2.5-3.5 inches basin wide should break it if outflows remain 29,000ish....any training ..all bets are off OH river crest without the big weekend system (both points running ahead of last nights forecast points) Paducah 49.5 cairo 53 both top 18 all time crests (even a slight increase will move up the list fast) Lake Barkley/KY lake levels about 755.1 feet. summer pool 759. record 772ish..outflows into OH 282,000 cfs the weekend event looks troubling because there is potential of the front to get hung up , usually poorly modeled, due to convection and training.....
  5. They have have increased flows out of Barkley again to 100K this evening....Ky lake still 188K... So 288,000 total into the OH...ALOT....for reference 600K (record) was the max outflow after the may 2010 event.. TVA page now says 238K from Kentucky alone expected on the 2OTH that wasn't the plan two days ago( see news article in my earlier post). I assume since the new crest on the OHIO will be higher and later....dumping out water now won't increase the peak so they want to ditch as much as possible util the crest gets closer
  6. so yesterday the TN river at Savannah was expected to rise to 390 feet (major 387) the 24th . just updated now says 385 and change....so they either plan on releasing less water from pickwick or expected less rainfall....or maybe both
  7. lake Cumberland now at 739.08 ft and rising up 2 feet the past 24 hours outflow 28,720....flow at Cumberland river at williamburg KY upstream 18,000 cfs expect to hit 27,000 by weds and hold above 24,000 all week there is obviously other inflow then the Williamsburg number but I think you get the point if other words inflow will be increasing going to get really interesting
  8. you will briefly get hit with the WF...(heavier west).but then likely a break...a big key for you is how much the firehose get pushed into north GA out of the watershed Thursday for a bit(6-9 hours maybe) before it heads back north with the next wave..
  9. yep....2 days ago it looked like SE TN was going to get 8 inches ..so they sent all this water down the river..it has to get into KY lake at some point...and then inot the OH river..so far not much reduction at Kentucky/Barkley but now areas more NW we get into the action too
  10. I assume (EURO) that some of that precip over central MS and AL is from the later system next week...better not have a north trend with that into the TVA watershed again
  11. with some for rain factored in ..I believe 48 hours so thru 12z weds... creast raised to 53 feet from 52 feet at Cairo next monday will TVA hold more water back now or later? looks like they are not slowing down the outflow that much .. huge amounts of water are planned to be dumped from the TN river into Kentucky lake this week
  12. I'm in Peoria IL..I just track and follow extreme weather events as a hobby(30+ years) , (ie the Oroville Dam mess and houston Harvey flooding) this is a unique situation...due to the record wet last year...and the fact soils are wet and runoff already very high...and with this system dumping so much water over a large area..at least it isn't later in the spring and lakes are closer to their summer pool already...the flip side that no green vegetation to help soaked up some of it yet.. the pattern better break after this .... 12z GVSFV3 nails Kentucky lake area 6-7 inches and you guys still 4-5 ....
  13. thru this weekends system..note: two days ago models wanted to blast a huge high from Canada down shutting this off..got delayed.....now trends are for more rain next week at least for southern parts of your area ....
  14. DAY 2 VALID 12Z TUE FEB 19 2019 - 12Z WED FEB 20 2019 ...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF THE SOUTHERN U.S. AND TENNESSEE VALLEY ON WEDNESDAY... THE MODELS CONTINUE TO SHOW A STRONG SIGNAL FOR WIDESPREAD HEAVY TO EXCESSIVE RAINFALL FROM PARTS OF ARKANSAS TO PORTIONS OF MISSISSIPPI AND TENNESSEE FROM TUESDAY NIGHT INTO WEDNESDAY. A MODERATE RISK REMAINS IN PLACE. THE LARGE SCALE SYNOPTIC PATTERN STILL FEATURES A DEEP-LAYERED TROUGH MOVING OUT OF THE ROCKIES AND ADJACENT HIGH PLAINS WHEN THE FORECAST PERIOD BEGINS ON TUESDAY MORNING. WINDS BECOME SOUTH AND ACCELERATE TO BETWEEN 45 KTS AND 60 KTS IN RESPONSE TO THE APPROACH OF THE MID-LEVEL HEIGHT FALLS AND INCREASING DIFLUENCE/DIVERGENCE ALOFT AS THE AXIS OF A 160 TO 180 KT UPPER LEVEL JET MOVES INTO POSITION. THE RESULT WILL BE A WELL-DEFINED MOISTURE PLUME GETTING PULLED NORTHWARD FROM THE GULF OF MEXICO...WITH MAXIMUM VALUES INCREASING TO AROUND 1.75 INCHES NEAR THE GULF COAST AND LESSER VALUES DOWNSTREAM. THE RESULT WILL BE INCREASING AREAL COVERAGE AND INCREASING RAINFALL RATES FROM THE GULF COAST INTO THE TENNESSEE VALLEY DURING THE LATTER HALF OF THE DAY 2 FORECAST PERIOD. THERE WERE SOME CONSISTENT SIGNALS IN THE NUMERICAL GUIDANCE THAT THE BEGINNING OF THE EVENT WILL BE DELAYED SOMEWHAT COMPARED WITH EARLIER THINKING...BUT THE ESTABLISHMENT OF THE DEEP MOISTURE PLUME AND DEVELOPMENT OF HEAVY/INTENSE RAINFALL IS STILL ON-TRACK WITH 3 TO 5 INCHES APPEARING TO BE THE MOST LIKELY RAIN...WITH LOCALLY HIGHER AMOUNTS. THIS RESULTED IN MAINTAINING THE MODERATE RISK AREA BUT ADJUSTING THE PLACEMENT OF IT AREA SOMEWHAT WEST OF WHERE IT WAS IN PREVIOUS OUTLOOKS. ALSO NUDGED THE EASTERN PERIHERY WESTWARD. TOO, SINCE IT APPEARS A BROAD SPRAWLING HIGH TO THE NORTHEAST OF THIS SYSTEM WILL STILL BE FEEDING STABLE AIR ON THE EASTERN FLANK...BUT LEFT THE SLIGHT RISK IN PLACE AT OR NEAR THE BOUNDARIES COLLABORATED ON SUNDAY. THERE OVERALL PLACEMENT SHOULD BE CONFINED IN A FAIRLY NARROW CHANNEL BETWEEN THE DEEP SYSTEM COMING OUT OF THE ROCKIES AND HEADED TOWARDS THE GREAT LAKES...AND THE SUBTROPICAL RIDGE TO THE SOUTH AND EAST. EVEN SO, THERE WAS DISAGREEMENT BETWEEN THE MODELS AS TO EXACTLY WHERE THE HEAVY RAINFALL WILL OCCUR AND WPC TENDED TO STAY BETWEEN THE WESTERLY ECMWF AND THE EASTERN OPERATIONAL GFS (WHICH WAS SIMILAR TO THE GFS-FV3). BANN DAY 3 VALID 12Z WED FEB 20 2019 - 12Z THU FEB 21 2019 ...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF THE SOUTHERN U.S. AND TENNESSEE/OHIO VALLEYS FROM WEDNESDAY INTO EARLY THURSDAY... A PROLONGED RAINFALL EVENT FROM THE GULF COAST STATES INTO THE OHIO VALLEY WILL BE ON-GOING AT THE START OF THE DAY 3 FORECAST AND LIKELY TO CONTINUE BEYOND 21/12Z. RAINFALL AMOUNTS MAY NOT BE AS GREAT AS THEY WERE ON DAY 2...BUT THE CUMULATIVE EFFECT OF OBSERVED AND FORECAST RAINFALL AMOUNTS IS MAXIMIZED OVER PORTIONS OF THE TENNESSEE VALLEY. A MODERATE RISK AREA OF EXCESSIVE RAINFALL WAS PLACED WHERE THE OVERLAP APPEARED GREATEST FROM THE DAY 2 AND DAY 3 WPC QPF. THE AXIS OF HEAVIEST PRECIPITATION FROM DAY 2 WILL BE EASING EASTWARD OVER PARTS OF MISSISSIPPI AND ALABAMA DURING THE PERIOD. WHILE RAINFALL RATES LOOK TO DIMINISH A BIT, ADDITIONAL RAINFALL APPEARS TO DEVELOP ALONG AND AHEAD OF A SLOW MOVING BOUNDARY ONCE AGAIN LATE ON WEDNESDAY NIGHT OR EARLY THURSDAY MORNING. THE PRIMARY FOCUS SHOULD BE EAST OF THE AREA THAT GETS THE HEAVIEST RAINFALL ON DAY 2...BUT PORTIONS OF NORTHERN ALABAMA OR SOUTHERN TENNESSEE MAY HAVE 48-HOUR RAINFALL AMOUNTS ON THE ORDER OF 3 TO 5 INCHES DESPITE MODEST RAINFALL AMOUNTS EACH DAY. FLASH FLOOD GUIDANCE NUMBERS LOOK TO DECREASE IN RESPONSE. ELSEWHERE, MODEL GUIDANCE HAS BEEN INCREASING SPREAD AS TO HOW FAR NORTH THE FIRST WAVE OF RAINFALL WILL MAKE IT AND WHEN/WHERE THE NEXT ROUND INITIATES. AS A RESULT, THE CONFIDENCE ELSEWHERE WAS TOO LOW TO WARRANT A MODERATE RISK AREA EVEN THOUGH CONFIDENCE IS PRETTY HIGH THAT THERE WILL BE ANOTHER PHASE OF THIS LONG-TERM RAINFALL EVENT. A SLIGHT RISK AREA WAS PLACED FROM THE SOUTHERN TIER OF STATES ALONG THE GULF COAST TO THE OHIO VALLEY. DID NOT EXTEND EITHER THE SLIGHT RISK OR MARGINAL RISK AREAS EAST OF THE APPALACHIANS INTO THE MID-ATLANTIC REGION GIVEN POTENTIAL FOR WINTER WEATHER CONCERNS. BECAUSE THIS IS A LONG-TERM EVENT, ADDITIONAL RAINFALL IS EXPECTED ALONG OR NEAR THE AXIS WHICH HAS BEEN HIGHLIGHTED IN THE CURRENT DAY 2 AND DAY 3 RAINFALL FORECAST, REFER TO QPF AND DISCUSSIONS FROM THE WPC MEDIUM RANGE SECTION FOR ADDITIONAL INFORMATION ABOUT THURSDAY AND BEYOND.
  15. after this period a little pattern change...perhaps ..models move a strong high down form Canada...flattening the flow however, models seem to want to rebuild the pattern somewhat (more like strong southern jet) but perhaps more south in the 10-15 day time frame...but some of the members hit you guys again the first graphic is the 10 day mean and the last is the full 16 day run..the increase in t he second image is mostly from some members nailing you guys again
  16. 12z NAM still hits the OH river hardest with the first wave Lake cumberland rising rapidly 738.32 as of 6am...up 1.5 feet in 18 hours
  17. trends are still trending NW.....may be the case now where no one gets the huge 8-10 inch amounts but more get 4-5+(i.e. OH valley.too) ..of course convection could slow/stall the north movement of any warm front too 06z GFS now has the final wave max pecip north of the OH river I have noticed WPC forecast lags trends.....and river forecast are based on WPC I think
  18. as of 4pm today Nashville up to 8.07 for the month, including 1.24 today FEB RECORD 12.37 in 1880 Wettest month on record MAY 2010 16.43 (most fell in 2 days) Lake Cumberland rising again at 736.89 ..the watershed got hit pretty good today . outflow still holding at 28,000. record 751 feet and change.. I think odds are increasing it will pass that mark....top of flood pool 760.. do you cut back on outflows to help downstream flooding? hold steady? or increase to 35K to keep the lake from rising faster?
  19. 18Z NAM with yet another tick NW with the Tuesday/weds system..now nails OH River perhaps a concern is they are expecting the huge rain amounts in SE TN..so they are sending all this water down TN River below Pickwick into the OH river eventually? what is the heaviest falls more NW with the increased flows from the TN too?
  20. Tennessee Valley Authority ‏ Verified account @TVAnews 2h2 hours ago More In the East Tenn. area we are releasing very high flows from the tributary dams (Norris, Cherokee, Douglas, etc.) and expect to make reductions as early as tomorrow to begin storing water. Continue moving tremendous amounts of water down the Tenn. River.
  21. well the 1-3 precip updates on WPC are in so are the 4-5 days and 6-7 but the total day 5 and day 7 not updated yet.(the sum of the above)..both should be interesting to say the least..plus that doesn't include precip before 00z this evening right now weak thunderstorms training up the cumberland river watershed... so far they haven't increased outflow at lake cumberland to the 35,000 planned...lake level down only an inch since the peak yesterday over 3/4 inch at nashville so far today no2 over 7.5 for the month...should break the FEB record with ease now (11-12ish forgot the exact amount)]
  22. small slight risk added for today Excessive Rainfall Discussion NWS Weather Prediction Center College Park MD 1008 AM EST Sun Feb 17 2019 Day 1 Valid 15Z Sun Feb 17 2019 - 12Z Mon Feb 18 2019 ...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF THE SOUTHERN APPALACHIANS... ...Tennessee Valley/Cumberland Plateau/Southern Appalachians... The 12Z hires model suite suggests multiple rounds of moderate to heavy rainfall over the next 12 hours as multiple shortwave impulses embedded within strong deep layer southwest flow advance off to the northeast this afternoon and evening. In fact, the 12Z NAM and recent runs of the HRRR guidance support a low level jet reaching as strong as 50 kts and nosing in across the southern Appalachians by around 00Z. Strengthening frontogenetical forcing, backing mid/upper level flow aloft (favoring strong deep layer jet-aided ascent) and enhanced moisture transport/convergence with PWATs increasing to near 1.25 inches should favor an axis of moderate to heavy rain across the TN Valley and adjacent areas of the southern Appalachians. A relatively broad Marginal Risk area has been highlight across these areas given concerns at a minimum over locally wet antecedent conditions. However, the heaviest rainfall amounts which may exceed 1.5 inches, through 06Z tonight should be focused over southeast TN, far northern GA and southwest NC where the best nose of the low level jet and at least some modest instability will favor heavier rainfall rates and also working in tandem with stronger orographic forcing. Given the expected rainfall, and wet antecedent conditions, it is expected that ongoing runoff concerns will be further enhanced and become more widespread. also older day 3 outlook Excessive Rainfall Discussion NWS Weather Prediction Center College Park MD 326 AM EST Sun Feb 17 2019 Day 3 Valid 12Z Tue Feb 19 2019 - 12Z Wed Feb 20 2019 ...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF THE SOUTHERN U.S. AND TENNESSEE VALLEY ON WEDNESDAY... Heavy rainfall will begin Tuesday afternoon and continue beyond the end of the Day 3 forecast period on Wednesday morning...with much of the 17/00Z guidance showing an axis of 2 to 5 inches of rainfall by the end of the Day 3 forecast period at 12Z Wednesday. Given expected rainfall rates and training of cells/repeat convection, WPC hoisted a Moderate Risk of Excessive Rainfall. A system moving out of the Southern Rockies and adjacent High Plains will induce falling surface pressure over the southern tier of states on Tuesday. Low level winds become southerly along the Gulf Coast and accelerates to between 45 kts and 60 kts by Wednesday morning. The low level jet and the associated moisture transport vectors are expected to peak between 4 and 5 standardized anomalies ahead of the system...and maximum precipitable water values increasing to near 1.75 inches along the Gulf Coast. Rainfall is expected to become more widespread with rainfall rates increasing Tuesday night due to increase low level moisture in addition to mid level shortwave energy sweeping in from the west. Aloft, the entrance region of a 160 kt to 180 kt jet will set up increasing amounts of divergence/difluence by the end of Day 3...with increasing threat for flash flooding from either cell training or multiple rounds of convection at any given spot. WPC QPF opted for a position a bit east of the 16/12Z ECMWF moisture/QPF axis (and certainly more east of the 17/00Z ECMWF run)...but not as far east at the 17/00Z operational run of the GFS largely based on the bias of each model. The idea to not be as far east as the 17/00Z GFS was supported by the 17/00Z run of the GFS-FV3 which tended to offer more support to the 16/12Z ECMWF idea. Over time, the system becomes increasingly convective and the axis of heaviest rainfall pivots from a southwest-northeast orientation on Tuesday morning to one more south-north early Wednesday morning. This is the beginning of a prolonged period of heavy to excessive rainfall event which is expected to continue well beyond the end of the Day 3 forecast. For precipitation forecasts for Thursday and beyond, refer to graphics and dicussions from the WPC Medium Range section.
  23. 12z NAM another inch NW bump on the "tuesday night" wave 3+ inches over central KY..most of guys about an inch edit GFS too (in thru 69 hr)
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