Friday, June23, 2017 L-36.com


Marine Weather and Tides
Dawsonville, GA

Version 3.4
What's New / NOTES
5/23/2017 - Worked with NOAA again to speed up the 7 day forecast load times. Thanks to them for being responsive.
5/19/2016 - There were issues with the 3 day airport observation history. I switched to another data source. Let me know if you see any issues with the data feeds.

Sunrise 6:23AMSunset 8:52PM Friday June 23, 2017 2:51 PM EDT (18:51 UTC) Moonrise 5:04AMMoonset 7:28PM Illumination 0% Phase: New Moon; Moon at 29 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 Dawsonville, GA
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location: 34.43, -84.12     debug


Area Discussion for - Peachtree City, GA
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Fxus62 kffc 231831
afdffc
area forecast discussion
national weather service peachtree city ga
231 pm edt Fri jun 23 2017

Prev discussion issued 735 am edt Fri jun 23 2017
prev discussion... Issued 352 am edt Fri jun 23 2017
short term today through Saturday ...

airmass remains very tropical in nature across the cwfa. Convergence
zone has set up across the far NW cwfa this morning, and light to
occasionally rainfall will continue to fall this morning. So, far
rainfall amounts have been fairly light, but continued rainfall will
serve to help saturate the ground.

The remnants of cindy will push eastward, and interact with shear
axis weak convergence boundary through Saturday. This shear
axis weak convergence zone will slowly sag south across the cwfa
through Saturday, serving to focus areas of precipitation.

Speaking of saturated ground, heavy rainfall has fallen across the
metro area and interstate 20 corridor over the last week. As the
remnants of cindy move east and interact with the weak
boundary shear axis, today through early Saturday, additional
locally heavy rainfall is likely. Training storms would be the most
likely culprit, but a few strong thunderstorms could also develop
and produce locally heavy rainfall. Will be issuing a flash flood
watch for roughly the interstate 20 corridor and northward through
Saturday. Even though the far NE mountains haven't received as much
rainfall over the last week as some areas, do think some localized
flooding is possible... And the complex terrain does increase the
potential.

As with any tropical system, the potential for severe weather will
exist. Especially for isolated tornadoes within any rainbands. Areas
roughly along and west of the interstate 85 corridor will have the
best potential for any severe weather through tonight. However, if
good heating occurs across the southern cwfa today, an isolated
severe thunderstorm isn't out of the question either. In addition,
the coverage of storms should be less down south - with the only
focusing mechanisms for precip would be mesoscale boundaries or
differential heating boundaries.

The axis of heavier rainfall begins to shift southward on Saturday.

Areas mainly south of interstate 20 haven't seen as much rainfall in
previous days, so additional watches are not likely at this time.

Nlistemaa
long term Saturday night through Thursday ...

a welcome change is headed our way in the long term as drier air
moves into the region.

The remnants of TS cindy will continue to kick out to the north
and east with some residual moisture hanging along a cold front
that will push south Saturday night into Sunday. Anticipate
shower thunderstorm activity to dwindle through the overnight into
early Sunday given loss of day time heating and upper level
support. The front will eventually sag south of the area with much
of the precipitation activity confined to the far southern
portion of the cwa. Thus anticipate diurnally driven thunderstorms
Sunday afternoon across this region. The front will eventually
wash out with strong high pressure building into the area for the
beginning of next week. The surface high will eventually shift
across the mid-atlantic and then out to sea by Thursday. Return
flow will usher in a bit more moisture into the region with
temperatures slowly on the increase. This will mean higher
diurnal thunderstorms coverage, especially by next Friday.

Given cooler high pressure and a much drier airmass moving in,
temperatures will be below normal... Feeling quite pleasant.

26
prev discussion... Issued 320 pm edt Thu jun 22 2017
long term Saturday through Thursday ...

the remnants of tropical storm cindy will finally be out of our hair
at the beginning of the long term forecast period on Saturday
morning. However there will be a cold frontal boundary moving south
across the area. Rain and thunderstorms will be ongoing along the
front... Enhanced by diurnal heating in the afternoon. There looks to
be enough deep layer shear 0-6km of 20-30kts as a broad trough
deepens across the eastern 2 3rds of the us to work in conjunction
with instability INVOF the front. This should allow for some
organization of thunderstorm clusters along the front. The main
threat will be damaging wind gusts. SPC has a large majority of
central and eastern georgia in a marginal risk.

The front will make slow progress into central georgia Saturday
evening into the overnight hours but the loss of daytime heating and
rather poor forcing should allow most activity to gradually
dissipate. Front looks to linger across far southern zones on Sunday
where again diurnal heating should allow for a gradual increase in
thunderstorm activity through the afternoon. Shear appears to be
displaced too far north to pose a notable severe threat by this
time. Can't rule out isolated stronger storms... But think Saturday
has better parameters than Sunday.

Front should clear the CWA by Monday. A rather unseasonably
strong area of sfc high pressure will gradually build into the
region from the north in the wake of the front... Which will make
for a dry day. A strong shortwave rotating around the broad scale
trough over the eastern us will likely bring some clouds to area
on Tuesday... But thinking large dome of sfc high pressure will
keep things dry. Height rises in the mid level behind this
shortwave combined with sfc high pressure should make for a very
pleasant Wednesday. Will see moisture gradually return outside of
the extended as the sfc high begins to scoot off the atlantic
coast.

Kovacik

Aviation
18z update...

isolated to scattered showers and thunderstorms will impact the
area today, largely focused along a boundary as it moves through
northwest georgia tonight. Thinking best tsra potential is 00-04z
through the atlanta metro area. Light rain will be off and on
tonight through the morning hours, with additional storms
developing late morning and through the afternoon Saturday. Expect
vfr CIGS today to degrade to ifr by 06z, with slow improvement
after 14z. Precip will taper off by early evening, with improving
ceilings. Winds will remain west at 6-12kt and higher gusts to
20-25kt this afternoon and associated with convection.

Atl confidence... 18z update...

medium confidence on all elements.

31

Preliminary point temps pops
Athens 89 73 85 69 30 60 60 20
atlanta 88 73 82 68 40 70 70 20
blairsville 83 67 79 60 60 80 60 5
cartersville 87 72 82 65 60 80 70 10
columbus 91 75 86 72 20 50 60 30
gainesville 86 72 82 67 50 70 70 10
macon 91 74 87 72 20 30 60 30
rome 87 72 83 65 70 90 60 10
peachtree city 88 73 83 68 30 60 70 30
vidalia 92 75 91 74 40 20 50 30

Ffc watches warnings advisories
Flash flood watch through Saturday evening for the following
zones: banks... Barrow... Bartow... Carroll... Catoosa... Chattooga...

cherokee... Clarke... Clayton... Cobb... Coweta... Dade... Dawson...

dekalb... Douglas... Fannin... Fayette... Floyd... Forsyth... Gilmer...

gordon... Gwinnett... Hall... Haralson... Heard... Henry... Jackson...

lumpkin... Madison... Murray... Newton... North fulton... Oconee...

oglethorpe... Paulding... Pickens... Polk... Rockdale... South
fulton... Towns... Union... Walker... Walton... White... Whitfield.

Tornado watch until 9 pm edt this evening for the following
zones: catoosa... Chattooga... Dade... Floyd... Gordon... Murray...

walker... Whitfield.

Short term... 31
long term... .Baker
aviation... 31


Weather Reporting Stations
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Gainesville, Gilmer Memorial Airport, GA19 mi59 minSSW 9 G 1910.00 miFair85°F69°F59%1014.7 hPa

Wind History from GVL (wind in knots)
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Last 24hrSE7E8E7E4E74SE6SE4SE4SE3SE4S5SW3S3S3SW5SW5SW5SW5SW9SW8
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1 day agoSE5SE4S4S3CalmCalmCalmS8CalmN3CalmNE3E3E3NE3NE4CalmNE6E5E4E6E5E7E7
2 days agoSE5E11E9SE4E4E4CalmS3S4SW5SW4SW4CalmSW4CalmCalmS3CalmCalmCalm5SE5SE3S3

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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Weather Map
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IR Satellite Image from GEOS
east_satellite

GOES Local Image of Southeast    EDIT
Geos

Wind Forecast for Peachtree City, GA (14,3,4,5)
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Ground Weather Radar Station Atlanta, GA
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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.