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TN valley heavy rain/flooding week of whenever

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Tennessee Valley Authority
53 mins · 
The River Forecast Center is tracking significant rainfall with numerous rounds of heavy rain beginning as early as Monday and continuing through the week. Most of the heavy rain is expected Tuesday through Thursday.
We are preparing by increased releases from the tributary reservoirs like Norris, Douglas, and Cherokee to create as much storage space as possible. On the main stem Tennessee River, reservoirs are being pulled down to below winter pool to have some storage and handle local inflows. 
We continue to work with the US Army Corps of Engineers to help reduce flooding on the Ohio and Mississippi Rivers.
This rain event could result in high river flood stages, especially in Alabama and below Pickwick in the Savannah to Johnsonville areas.
River stage info:
Chattanooga, TN: http://tva.me/XehH50lyZqL
South Pittsburg, TN: http://tva.me/8XyT50lyZqK
Whitesburg, AL: http://tva.me/ZM9T50lyZqP
Florence, AL: http://tva.me/lpmw50lyZqN
Savannah, TN: http://tva.me/Eam150lyZqO
Clifton, TN: http://tva.me/7Bkb50lyZqM
Perryville, TN: http://tva.me/vNt650lyZqQ
 

Day 9 image not available

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Wolf Creek Dam increasing releases to drawdown Lake Cumberland

 

NASHVILLE, Tenn. (Feb. 15, 2019)– The U.S. Army Corps of Engineers Nashville District plans to increase releases at Wolf Creek Dam in Jamestown, Ky., as soon as conditions allow in an effort to drawdown the water level at Lake Cumberland.

 


Water managers at the Nashville District headquarters in Nashville, Tenn., said Wolf Creek Dam is currently discharging water at a rate of 28,000 cubic feet per second, but plan to increase to 35,000 cfs as soon as conditions allow. 

The current elevation at Lake Cumberland is the highest observed since April 25, 1998 when the pool crested at 742.44 feet.  The pool of record is 751.69 set in May 1984. 

In 2019 inflows are averaging 33,270 cfs and the lake has risen 19 feet

Wolf Creek Dam last discharged water at a rate of 35,000 cfs in March and April of 1997.  The flow of record from Wolf Creek Dam is 40,000 cfs in January 1974.  River View Road had not been developed at that time.

 

 

https://www.dvidshub.net/news/310958/wolf-creek-dam-increasing-releases-drawdown-lake-cumberland

Local dams to release less water, hope to reduce flooding impact downstream (KY lake and Barkley into OH river)

 

As the Ohio River reaches its peak, Looney says less water will be released out of the dams, causing lake levels to rise above typical summer levels. He says that should also help reduce the impact of flooding downstream.

https://www.wpsdlocal6.com/2019/02/14/local-dams-to-release-less-water-hope-to-reduce-flooding-impact-downstream/

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Picked up 1.01" overnight, with a rise of 1.2' on the Tellico River. Currently at 3' (Flood stage is 9') some of the banks start topping a little sooner. One of the interesting things was how long it took to recede, continued rising 5 hrs after the rain stopped. Normally it takes a little less than an hour for the graph to begin falling, shows how much runoff is coming down the mountain.

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MRX AFD:

Main flooding concern starts late Tuesday and Tuesday night. Strong
upper jet becomes established over the Ohio and Mississippi Valleys
with strong upper divergence over the area from Tuesday night
through Wednesday night. The direct circulation around this jet
enhances the fronto-genetic forcing over the area and intensifies
the 850mb southerly jet pulling in unseasonably high moisture. PWs
increase to 1.4 to 1.5 inches which is above the daily climatology
maximum. Another concern is that freezing heights are quite high
which are also well above the daily climatology maximum. Layer
above freezing will be greater than 10kft over much of the area
helping to produce high rainfall rates.

End result, another round of heavy rainfall over already saturated
ground/high stream flows will set the stage for the potential of
serious flash flooding concerns, especially over the Plateau,
central-southern Tennessee, and southwest North Carolina. Will
highlight this concern in the Hazardous Weather Outlook and
Hydrologic Outlook.

The persistent southwest flow continues through the end of the week
with the potential of additional moderate to locally heavy rains
for Thursday through Saturday. Overall, a very wet pattern with
flooding concerns continuing.

River flooding looks to be a major problem as well from mid to late
next week, possibly into the next weekend.

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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.

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I don’t think I can remember ever seeing this much rain forecast with so little convection. Of the roughly 10” qpf at KCHA forecast next week, only 1.50” is convective on the 12Z GFS.  Probably means the likelihood of totals busting high or low is minimal. 

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well yesterday it was reported flows would be reduced from Kentucky lake and Barkley into the OHIO river...so far outflows from the combined dams have only dropped from  a combined 323,000 cfs to  280,000 cfs which is still a huge amount 

they also are still releasing  177,000 from Pickwick I (was 114K 2-14) into basically the start of Kentucky Lake...and the downstream hydrography suggest they may increase it? plus another 10K from buffalo and Duck

the Cumberland river into Barkley is at 74,000 bfs at Dover,  so a combined 261,000 cfs plus local runoff going into Ky lake and Barkley)  ...180,000 out

the OH river will crest soon at Cairo at 52 feet, the 20th highest on record (61.7 2011) and hold steady for 5- 6 days before falling

that is WITHOUT most of next weeks rain factored in.....which is creeping more north into more of the OH valley ,,,each run...

you can bet they are heaving heated discussions on what to do with all of the water...I suspect they will store it in Kentucky and Barkley to a point until the OH river crest passes...

Kentucky lake level 353.9 and  slowly rising now,,,normal summer pool is 359 I think the record is 372 or something in 2011 when they stored It until the OH crest passed..

-----

lake Cumberland 736.90. looks like it crested at 736.94...with 28,100 cfs outflow ...as of yesterday they were going to increase that to 35,000 after they build flood walls (record 40K) Dale hollow, just downstream is releasing 5,000 cfs the max combined allowed release is 40K I think....

note: Nashville needs 5.55 inches to break the monthy record

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49 minutes ago, Windspeed said:

Uptick QPF a bit further on the 00z. I hope this busts.9af302b7eb84d3bfebae591890a22290.gif

That far NW corner of north Georgia is in the south chickamauga creek watershed. That creek represents the largest flood threat to the Chattanooga metro. It was impounded with levees after the 1973 floods. The last time they were tested was May 2003. We could have a comparable crest to that event next week. 

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10 minutes ago, dwagner88 said:

That far NW corner of north Georgia is in the south chickamauga creek watershed. That creek represents the largest flood threat to the Chattanooga metro. It was impounded with levees after the 1973 floods. The last time they were tested was May 2003. We could have a comparable crest to that event next week. 

info on the 2003 event

The Major to Record Flooding of May 2003 across East Tennessee

 

 During the four day rain event (beginning at midnight on May 5th and ending at midnight on May 8th), a bull’s eye of over twelve inches of rain was reported in McMinn County, TN at both Etowah and Athens. The heaviest rains fell during the first 35 hours (midnight May 5th through 11:00 P.M. May 6th), where 11.6 and 11.1 inches fell at Etowah and Athens, respectively. Storm total rainfall of greater than six inches fell somewhere in each county south of a Sevier to Morgan County line. In the Little Tennessee River and Hiwassee River basins, greater than nine inches fell during the entire event. All of this water drained into Watts Bar and Chickamauga Lakes, which eventually flowed down to Chattanooga.

https://www.weather.gov/mrx/may03flood

 

 

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1 hour ago, dwagner88 said:

I don’t think I can remember ever seeing this much rain forecast with so little convection. Of the roughly 10” qpf at KCHA forecast next week, only 1.50” is convective on the 12Z GFS.  Probably means the likelihood of totals busting high or low is minimal. 

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    


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00z NAM NW with the first wave.(well second wave if you count tomorrow as the first)..max of 3.25 inches  or so in southern KY thru 84 hour

still 1.5 to 2.5 over much of eastern TN

very little of it falls outside the OH valley watershed (aka south of TN river) and more over KY near the river itself

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I thought that I saw someone posting in here yesterday that they saw a pattern change in the extended. I am not seeing it, am I looking in the wrong place? By end of the week, I would think the region would be uniquely positioned to be experiencing flooding, not sure we are to 2010 levels yet but we have got to be getting close. 

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Hunstville ...

AS ONE WOULD EXPECT   
FROM GUIDANCE 3+ DAYS OUT, THE PERIOD OF HEAVIEST RAINFALL NOW   
APPEARS TO BE LATE WEDNESDAY INTO EARLY THURSDAY DUE TO THE STALLING   
FRONT. AN ADDITIONAL 2-3" OF RAIN WILL FALL IN THIS PERIOD WITH  
LOCALLY HIGHER AMOUNTS POSSIBLE. THE STALLED BOUNDARY WILL BRIEFLY   
MOVE SOUTH AND EAST OF THE AREA LATE THIS WEEK, WHICH MAY INTRODUCE   
ANOTHER BRIEF PERIOD WITHOUT RAIN. RAIN TOTALS FROM TODAY THROUGH   
NEXT FRIDAY WILL BE WIDESPREAD 5-8", WITH ISOLATED AREAS POTENTIALLY   
10"+
. IT IS ALSO NOTEWORTHY THAT MODEL SOUNDINGS INDICATE 200-500   
J/KG OF CAPE THROUGHOUT THE WEEK, INTRODUCING THE POSSIBILITY OF   
ISOLATED TO SCATTERED THUNDERSTORMS WITHIN THE HEAVY RAINFALL.   
STRONGER CONVECTION WILL LEAD TO ISOLATED HIGHER RAINFALL TOTALS.  

  
ALL GUIDANCE IS AGAIN ABNORMALLY CONSISTENT WITH ANOTHER WAVE   
EJECTING OUT OF THE WESTERN US TROUGH, BRINGING ANOTHER ROUND OF   
HEAVY RAINFALL NEXT WEEKEND. THIS WOULD CAUSE THE COLD FRONT TO  
RAPIDLY RETREAT AGAIN OVER THE TN VALLEY AS A WARM FRONT. WITHIN THE  
WARM SECTOR, THERE IS THE POSSIBILITY FOR STRONG STORMS NEXT   
SATURDAY INTO SUNDAY. ESTIMATED ADDITIONAL RAINFALL TOTALS FOR NEXT   
WEEKEND WOULD BE 1-2" ON TOP OF WHAT WE EXPECT THIS WEEK.
 

 

CURRENT ANALOGIES   BEING USED ARE THE FLOODING EXPERIENCED ON CHRISTMAS IN 2015, AND   POTENTIALLY AS BAD AS THE SPRING FLOODS OF 2003.    

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0z Euro still with widespread 6 - 7.5" through TN and Ohio watersheds. Some areas 8+. 

WPC basically sums it up. And that discussion above as well.

Just amazing how wide the 7 - 10 inch field is.

giphy.gif 

Weathertree I think janetjanet mentioned that a run of the GFS yesterday broke the pattern down, but (janetjanet can correct me if wrong) I took that as just a hopeful mention of what that model depicted as a way out of this awful pattern. 6z GFS is back to this;

giphy.gif 

Basically GFS think we are one of the most soaked places on earth over the next 15 days. Good news is that it's just one run of the GFS. 

That being said, the 0z Euro really flattens the jet after day 7-8 and that would help a lot. Maybe not totally shut off precip, but at least stop this training mess. 

The Euro control (Euro itself run at slightly lower resolution), keeps it coming though, but with a slightly more suppressed flow. 

 

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3 hours ago, Holston_River_Rambler said:

0z Euro still with widespread 6 - 7.5" through TN and Ohio watersheds. Some areas 8+. 

WPC basically sums it up. And that discussion above as well.

Just amazing how wide the 7 - 10 inch field is.

 

Weathertree I think janetjanet mentioned that a run of the GFS yesterday broke the pattern down, but (janetjanet can correct me if wrong) I took that as just a hopeful mention of what that model depicted as a way out of this awful pattern. 6z GFS is back to this;

 

 

 

I think the GFS and GEFS had a NW flow for a few runs after next weekend  for a bit yesterday,,but seems more flat now..and in end of the run is back tiothe same pattern :(

 

 

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1 minute ago, Holston_River_Rambler said:

Yeah the bad part about this is that out current forecast period ends when a pattern like this is starting to become climatologically (at least in my experience)  favored for this area. 

 

Exactly! That is what I am concerned about. Personally moved from winter tracking a few days ago but knowing what I know about Spring in the TN Valley, we could be entering uncharted territory. For example, last Spring, the area just to the north of where I am got 5"- 6" of rain in a thunderstorm - May I believe - within a half hour, the large creek near me - Upper Station Camp, that flows into Old Hickory Lake - was out of its banks. Now, throw that same storm into the area this May and I honestly do not know what would happen!

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giphy.gif 

Big blocks being advertised by the Euro to develop across the N. Hemisphere. Hopefully if that happens they can effect some change in the pattern. But, as with all things this winter, 8 - 10 days. 

Looks like it might be snowy in N. Africa though. 

 

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1 minute ago, Holston_River_Rambler said:

 

giphy.gif 

Big blocks being advertised by the Euro to develop across the N. Hemisphere. Hopefully if that happens they can effect some change in the pattern. But, as with all things this winter, 8 - 10 days. 

Looks like it might be snowy in N. Africa though. 

 

Something off the modeling this Winter or maybe it is just me or a little of both. 

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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.
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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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SWS just issued for tonight from MRX:

Heavy rain forecast for today and tonight...

Showers leading to heavy rain across eastern Tennessee and SW
North Carolina for Sunday and Sunday night. Up to an inch and a
half is possible especially across the southern Tennessee valley
and the Smokey Mountains with possibly heavier local amounts. Due
to the saturation of the ground from previous rain events, most of
the rainfall is expected to result in excessive runoff with some
areas of localized flooding possible. Stream flooding, roadway
flooding, ponding of low level areas and potential mud slides are
all possible.

Lesser amounts are expected for the central valley region and
more northern areas of the forecast area, including the Cumberland
plateau. Due to saturated soils and rainfall from the last 24
hours, some local flooding could occur in the northern areas of
the forecast area as well.

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Picked up 0.11" so far today, and the gauge is already beginning to rise. There is zero water being soaked into the ground here, everything is going straight into the river. If we get anywhere close to 2003 level on the gauge, swift water teams will be deployed.

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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. 

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In addition to the flooding threat, there could also be a mountain wave event Tuesday night into Wednesday as a strong LLJ develops over the region with a favorable wind profile.  With the saturated ground, these strong winds along the mountains could cause some problems as well.   

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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)]

 

 

 

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