Wednesday, February20, 2019 L-36.com


Marine Weather and Tides
Knoxville, TN

Version 3.4
What's New / NOTES
10/6/2018 Colors of tide XTide graphs changed to emphasize that they were upgraded. See next note. Comments welcome.
10/4/2018 I have fixed XTide and updated the harmonic files. There were some name changes so you might have to click EDIT to find the new station name.

Sunrise 7:15AMSunset 6:23PM Wednesday February 20, 2019 6:33 PM EST (23:33 UTC) Moonrise 7:49PMMoonset 8:11AM Illumination 98% Phase: Waning Gibbous; Moon at 16 days in cycle
NOTE: Some of the data on this page has not been verified and should be used with that in mind. It may and occasionally will, be wrong. The tide reports are by xtide and are NOT FOR NAVIGATION.
Marine Forecasts
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7 Day Forecast for Marine Location Near Knoxville, TN
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location: 35.97, -83.95     debug


Area Discussion for - Morristown, TN
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Fxus64 kmrx 202043
afdmrx
area forecast discussion
national weather service morristown tn
343 pm est Wed feb 20 2019

Short term (tonight and Thursday)...

heavy rainfall is the main topic in the short term period.

Currently across the forecast area skies were cloudy with
temperatures in the upper 40’s to mid 50’s. The warmest areas
where near the foothills of the smokys where downslope conditions
have caused temperatures to warm up quicker than other locations.

Current radar shows a solid band of rainfall from the southern
mississippi valley north through the tennessee valley. The upper
levels are characterized by lower heights across the western conus
and plains with higher heights across the eastern conus. The main
synoptic feature to note is the potent shortwave trough quickly
ejecting northeast into the great lakes amplifying the upper
pattern. Closer to the surface, an area of low pressure was
analyzed across eastern mississippi with a parent low across the
midwest. A cold front extends from the midsouth low southward
through the gulf coast, with a warm front across southern alabama
and the florida panhandle.

The current band of rainfall has been situated along an zone of
enhanced 1000-925mb frontogenesis. However, warming cloud tops and
a weakening potential temperature gradient suggests low level
forcing is beginning to weaken. Further, the dynamic shortwave
trough is quickly ejecting northeast weakening upper level
support. This supports what hires model data suggests, which is a
weakening trend in the coverage of precipitation this afternoon
and evening. Moisture still remains high with precipitable water
values in excess of 1.5 and near boundary layer mixing ratio’s
greater than 8 to 9 g kg. While synoptic lift remains marginal at
best, low level frontogenesis and convergence should support
likely pops through the evening and overnight before the boundary
moves out of the area. Forecast soundings support a marginal
chance of elevated convection this afternoon with only a few
hundred joules of CAPE generated by models. Latest lightning data
shows a gradual decrease in convective activity this afternoon
which matches closely with the latest mesoanalysis MUCAPE with
better values south and west of the forecast area. However, if
thunderstorms could develop than this would exacerbate the
flooding threat with increased rainfall rates in areas that have
low flash flood guidance. The ongoing flood watch looks to be in
great shape and no changes will be needed.

As mentioned in the previous updated forecast discussion, have
extended the high wind warning, and wind advisory through 04z
tonight. The low level jet should still be positioned in an area
that would support high winds in the higher elevations of the
smokys. Tomorrow should be mostly dry as a surface high pressure
to the north pushes the low level boundary southward. However,
this high will move back northeast allowing the low level boundary
to begin to push northward by Thursday night.

Long term (Thursday night through Wednesday)...

Thursday night a warm front will be lifting northward through the
area. This is the same boundary that came through earlier in the day
on Thursday. The warm front advancing back northward is in response
to the cyclone developing across the four corners states and the
area of high pressure off to our southeast. Models are coming into
better agreement that this boundary stalls somewhere across the area
on Friday, providing focus for another round of moderate to possibly
heavy rainfall. It is very difficult to say exactly where this
boundary sets up but wherever it does is key to where the heaviest
precip will occur. It looks like another 1 to 1.5 inches of rainfall
is possible along the boundary from Thursday night through late
Friday evening. Areas further away from the boundary will see lesser
rainfall amounts, around 0.5 to 0.75 inches. We will have to watch
the boundary location closely as any moderate to heavy rain that
occurs has the potential to cause additional flooding. If models
still show the boundary stalled across our area over the next few
runs a flood watch may be needed during the day on Friday for some
areas.

Friday night through Saturday morning there is greater model
uncertainty regarding the movement of the boundary. The NAM lifts
the boundary north into ky Friday evening whereas the GFS keeps it
along the tn ky state line. At some point from Friday night through
Saturday morning the boundary does push north and gives us a brief
break from the moderate to heavy rainfall as we get deeper into the
warm sector. The break is short-lived though as the aforementioned
cyclone is moving in from out of the plains along with its
associated cold front. Southerly winds increase out ahead of the
front as the 850 mb jet strengthens. Gusty winds likely across the
high terrain from Saturday through Saturday night. The front pushes
through Saturday night into Sunday morning bringing another line of
showers and perhaps a few rumbles of thunder, but not confident
enough at this point to put thunder in the forecast. Another 0.5 to
0.75 inches of rain is possible with the precip associated out ahead
of and along the frontal passage. Storm total rainfall from Thursday
night through Saturday night ranges from around 1 inch up to 2.5
inches.

Sunday through Tuesday looks drier as we are in northwest flow. Late
Tuesday we return to a southwest flow as high pressure develops to
our east. Another shot of precip moves in for Tuesday night through
Wednesday as another cold front pushes through the area.

Preliminary point temps pops
Chattanooga airport, tn 48 56 48 56 80 60 70 80
knoxville mcghee tyson airport, tn 48 56 46 53 80 40 70 90
oak ridge, tn 47 58 46 53 80 30 70 90
tri cities airport, tn 48 58 44 51 80 30 60 80

Mrx watches warnings advisories
Nc... None.

Tn... Flood watch through Thursday morning for anderson-bledsoe-
bradley-campbell-claiborne-east polk-grainger-hamilton-
hancock-knox-loudon-marion-mcminn-meigs-morgan-nw blount-
northwest monroe-rhea-roane-scott tn-sequatchie-southeast
monroe-union-west polk.

High wind warning until 11 pm est this evening for blount smoky
mountains-cocke smoky mountains-sevier smoky mountains-
southeast greene-southeast monroe-unicoi.

Wind advisory until 11 pm est this evening for johnson-southeast
carter.

Va... Flood watch through Thursday morning for lee-wise.

Wind advisory until 11 pm est this evening for russell-
washington-wise.

Ad sr


Weather Reporting Stations
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Knoxville, McGhee Tyson Airport, TN11 mi41 minSE 32.00 miRain Fog/Mist48°F46°F96%1014.5 hPa
Oak Ridge, TN15 mi41 minN 04.00 miLight Rain Fog/Mist48°F48°F100%1015.5 hPa

Wind History from TYS (wind in knots)
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Last 24hrN9NE8N9NE8E6NE7NW6CalmCalmN3N4NW4N4N4N5NE5N7N7N63N6NE4W8SE3
1 day agoN8N16NE13NE8N8N7N7NE8NE8NE6NE5NE7NE8NE9NE9NE11NE9NE8N5E4NE4NE7NE5E8
2 days agoNW6NW7
G17
S3S6SW7SW9SW7W10W13W12
G27
W6SW7W8SW8SW9W11W12W12SW9W11W11W7W6W4

Tide / Current Tables for
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Tide / Current Tables for
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Weather Map and Satellite Images
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GOES Local Image of    EDIT
NOTE: East coast views moved to GEOS-16. They are experimental and not well supported by NOAA so they may not be correct so be warned. This change required redoing a large amount of the GOES code. If the image you are expecting is not showing, please let me know. You may need to use the EDIT function to update your location.
Link to Loop

Other links: Northern Pacific     Contential US     Full GOES-East
Wind Forecast for Morristown, TN (18,4,5,8)
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Ground Weather Radar Station Knoxville/Tri Cities, TN
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Disclaimer:
The information on this web site has not been checked for accuracy. It is for entertainment purposes only and should be independently verified before using for any other reason. There are five sources. 1) Documents and manuals from a variety of sources. These have not been checked for accuracy and in many cases have not even been read by anyone associated with L-36.com. I have no idea of they are useful or accurate, I leave that to the reader. 2) Articles others have written and submitted. If you have questions on these, please contact the author. 3) Articles that represent my personal opinions. These are intended to promote thought and for entertainment. These are not intended to be fact, they are my opinions. 4) Small programs that generate result presented on a web page. Like any computer program, these may and in some cases do have errors. Almost all of these also make simplifying assumptions so they are not totally accurate even if there are no errors. Please verify all results. 5) Weather information is from numerious of sources and is presented automatically. It is not checked for accuracy either by anyone at L-36.com or by the source which is typically the US Government. See the NOAA web site for their disclaimer. Finally, tide and current data on this site is from 2007 and 2008 data bases, which may contain even older data. Changes in harbors due to building or dredging change tides and currents and for that reason many of the locations presented are no longer supported by newer data bases. For example, there is very little tidal current data in newer data bases so current data is likely wrong to some extent. This data is NOT FOR NAVIGATION. See the XTide disclaimer for details. In addition, tide and current are influenced by storms, river flow, and other factors beyond the ability of any predictive program.