Saturday, May27, 2017

Marine Weather and Tides
Franklin, NC

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 6:18AMSunset 8:37PM Saturday May 27, 2017 1:23 PM EDT (17:23 UTC) Moonrise 7:19AMMoonset 9:47PM Illumination 5% Phase: Waxing Crescent; Moon at 2 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 Franklin, NC
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location: 35.1, -83.39     debug

Area Discussion for - Greenville-Spartanburg, SC
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Fxus62 kgsp 271530
area forecast discussion
national weather service greenville-spartanburg sc
1130 am edt Sat may 27 2017

Warm and humid air will return to the region today through at least
Monday, as high pressure settles east of the florida coast. A cold
front will slowly approach from the northwest, but will struggle to
push through the area during the middle of next week.

Near term through tonight
As of 1035 am: flat ridge over the region will continue to gradually
break down through tonight. A series of weak vort maxes, some of
which are likely convectively-induced, will pass through the ridge
into the eastern CONUS through the period, primarily from this
evening into the short term period. Obviously, convective trends
later today into tonight are the forecast challenge for the next 24
hours, and uncertainty continues to abound. First of all, regional
12z raobs are pretty astounding, capturing an expansive elevated
mixed layer, with near-dry adiabatic lapse rates from around 800 mb
to the tropopause shown on the ffc sounding. You just don't see
soundings like this everyday in the southeast coastal states.

However, as with any EML sounding, it is also capped, and quite
formidably so (low level moisture also needs some work, but that's
another story). Surface heating should put a fairly decent dent in
the cap, but it's highly unlikely that will be enough to remove it.

As such, we are not expecting much in the way of deep convection
through much (if not all) of the afternoon, but mid-level short
wave MCV approaching the area from the tn valley could provide
enough layer lift to remove the cap in some areas this evening, and
some short term guidance is suggesting this will be the case.

Looking upstream, regional radars over the tn valley depict
isolated generally waning convection across middle tennessee and
western kentucky, with an associated outflow boundary. This activity
will continue to diminish as it encounters more stable capped air to
its east. The question is whether remnant outflow will be able to
provide a focus for initiation of additional convection later today
across east tn and eastern kentucky, and if so what form it will
take (i.E., will it remain scattered discrete or organize into
something more significant). The most likely scenario is that
absence of strong forcing and the lack of a prominent surface
boundary to focus development, and somewhat limited (although still
significant) instability low level moisture should limit the overall
coverage to scattered discrete cells and perhaps a few small
clusters developing to our west and moving into the area from late
afternoon through the evening and perhaps the early part of the
overnight. Long straight hodographs may favor splitting supercells,
although the tornado threat should be very limited due to relatively
low rh in the boundary layer. Thus, damaging winds are the main
concern, and the dry bl should yield high dcape intense microburst
potential. The steep mid-level lapse rates relatively large CAPE in
the -10c to -30c layer will also yield a threat of large to very
large hail.

Tonight, an organized, likely severe MCS will be barreling through
the tn valley, and this will obviously create some concern for our
area, although a consensus of high res and short term model guidance
suggests it will have a fairly strong SE trajectory toward the more
unstable moisture rich environment across the deep south.

Short term Sunday through Monday
As of 300 am Saturday: the short term looks to be fairly active,
with a continued threat of severe weather. A flat upper ridge will
keep a deep layer westerly flow across the region. Embedded vort
maxes or mcvs will track thru this flow. The air mass within this
zone will be quite unstable, with guidance generally agreeing on an
axis of 2000-3000 j kg of CAPE extending from the mid-south east
thru the carolinas by late Sunday afternoon. Bulk shear should more
than adequate for organized storms. The exact evolution of this
activity is still in question, as guidance cannot time individual
mcvs even that far, and subtle differences in the amount of buoyancy
and shear may change the primary storm mode. Some convection
allowing models are now going out thru Sunday, and they are not in
very good agreement. Based on the forecast soundings, it does look
like we should have a lot less cin, and storms may start initiating
by midday, especially in the high terrain. Steering flow will take
this activity out across the piedmont mid late aftn thru the
evening. Pops still range from chc across the ga sc piedmont to
likely across most of the nc mountains. Temps will be one or two
categories above normal.

Sunday night thru Monday, an upper low will deepen and dig south
across the western great lakes, backing the mid and upper flow atop
the cwfa more out of the sw. A surface front will be approaching
from the west, but will slow as the flow becomes more parallel to
its orientation. So Monday is looking like another active day, with
the piedmont becoming the most unstable. Bulk shear looks about the
same magnitude as Sunday, but oriented more out of SW instead of
wnw. The new day 3 SPC outlook has just come in with a slight risk
from i-85 and southeast, with a marginal risk elsewhere, except the
tn border counties. So I will add a mention of severe weather
possible for Monday in the hwo. Temps remain above normal.

Long term Monday night through Friday
As of 330 am Saturday: an upper low will wobble east and then north
across the great lakes, shifting a longwave trough axis slightly
east into the ohio valley. The 00z suite of guidance now all stall a
cold front over the southern appalachians on Tuesday, with another
front pushing in from the NW early Wednesday, but also getting hung
up. So pops were tweaked upward for both Tuesday and Wednesday, but
still mainly in the slight chc to low-end chc range. Fortunately,
mid level lapse rates will be weaker, and severe threat should be
muted. Temps will be around normal.

Thursday may be the quietest day, as some drier air finally pushes
in from the west, as the upper trough axis shifts east and flattens
out. I went with superblend for the pops both Thursday and Friday,
but those may be too high, if the 00z model trends hold. Temps will
continue to be near normal.

Aviation 15z Saturday through Wednesday
At kclt and elsewhere: a shallow upper ridge will keepVFR
conditions in place through the day for most of the area. Winds will
remain out of the SW (nw at kavl) through the morning, with speeds
less than 10 kt throughout. High clouds will increase from the west
early with lowerVFR moving in by afternoon with convection likely
developing upstream over tn. The latest convection allowing models
permit some of this activity to move across the nc mountains in the
afternoon and possibly survive into the foothills and piedmont
during the evening. Prob30 tsra will be advertised throughout, with
low end afternoon gusts expected in the SW flow. Winds diminish
during the evening.

Outlook: thunderstorms and associated restrictions will increase
through Sunday. Conditions may remain unsettled through early to
middle to next week as a train of upstream convection may continue
to ride through the area from the west from time to time.

Confidence table...

15-21z 21-03z 03-09z 09-12z
kclt high 100% high 100% high 100% high 100%
kgsp high 100% high 100% high 100% high 100%
kavl high 100% high 100% high 100% high 88%
khky high 100% high 100% high 100% high 100%
kgmu high 100% high 100% high 100% high 100%
kand high 100% high 100% high 100% high 100%
the percentage reflects the number of guidance members agreeing
with the scheduled TAF issuance flight rule category. Complete hourly
experimental aviation forecast consistency tables and ensemble forecasts
are available at the following link:

Weather Reporting Stations
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Macon County Airport, NC9 mi48 minWNW 310.00 miMostly Cloudy76°F63°F64%1018.6 hPa

Wind History from 1A5 (wind in knots)
Last 24hrNW6N7NE8N4NW3CalmW3CalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalm
1 day agoW8W8
2 days agoW7

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
IR Satellite Image from GEOS

GOES Local Image of Southeast    EDIT

Wind Forecast for Greenville-Spartanburg, SC (13,3,4,5)
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Ground Weather Radar Station Greer, SC
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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 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 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.