Saturday, November18, 2017 L-36.com


Marine Weather and Tides
North Shore, VA

Version 3.4
What's New / NOTES
6/25/2017 - NOAA is having a major issue that impact the 7 day forecast load times. Many users are reporting problems. The issue has been reported.
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 7:01AMSunset 5:08PM Saturday November 18, 2017 3:16 AM EST (08:16 UTC) Moonrise 6:55AMMoonset 5:39PM 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 North Shore, VA
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location: 37.06, -79.61     debug


Area Discussion for - Blacksburg, VA
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Fxus61 krnk 180539
afdrnk
area forecast discussion
national weather service blacksburg va
1239 am est Sat nov 18 2017

Synopsis
Dry high pressure across the region tonight into Saturday will
give way to an approaching cold front that is forecast to sweep
through the region Saturday night. Much colder air on gusty
northwest winds will follow in its wake into early next week.

High pressure quickly regains control over our weather pattern
next week with little in the way of additional precipitation
expected.

Near term through today
As of 925 pm est Friday...

with temperatures dropping quickly this evening, decided to
lower low temperatures especially in the valleys overnight.

However, warm advection will hold temperatures up along the
ridges overnight into Saturday morning. Have a good night !
as of 624 pm est Friday...

made some minor adjustments in temperatures for this evening
into tonight. Adjusted cloud cover for tonight into Saturday.

Overall, forecast is in good shape for tonight.

As of 245 pm est Friday...

sprawling area of high pressure in place across the eastern ohio
valley, appalachians and piedmont region this afternoon. This is
leading to good sunshine, at times filtered by high cloudiness
spilling into the region from the west. Well to our west, a
southwesterly warm sector regime is in place across the tn valley
ahead of an organizing surface low near northwest kansas.

Overall, a rather uneventful first part of the evening as high
pressure begins to slide off to our east allowing for more of a
southerly return to commence. Periodic high clouds can be expected
to continue into the first part of the overnight, with temperatures
falling rather quickly through midnight. Later tonight, high clouds
become a bit greater in areal coverage with stronger warm advection
taking place, buoyed by what the 12z 3-km NAM depicts as a
southwesterly 35 to 40 kt 850 mb jet. Expect to see a rather wide
spatial variability in lows this evening, as lower-elevation deeper
mountain valleys remain decoupled enough to allow for radiational
cooling and lows in the 30s. Across the ridges though, effects of
southerly warm advection, higher wind flow and some radiational
effects should keep temperatures here from falling much farther than
the upper 30s to mid 40s.

Then Saturday begins the period of more active weather, especially
the latter half of the day. Clouds will continue to slowly lower and
thicken into a multilayered deck, earliest and lowest with western
extent. However some higher resolution guidance indicates some lower
stratus working its way northward into our southern blue ridge
foothills and upper nc piedmont in response to strong moisture
return. Of more notable interest is the increase in southwesterly
winds at elevations above about 3000 feet. Southwesterly jet should
continue to increase from the overnight into the day Saturday. By
mid to late afternoon, the 3-km NAM and the GFS indicate 850 mb
winds of 50 to 55 kts depending on the model. An inversion forecast
by the models may keep some of this from fully mixing, and it's
climatologically tougher to verify advisory criteria wind gusts on a
southwesterly component. Still, the best chance of highest
southwesterly gusts of up to 40 to 45 mph will be along the mountain
empire, grayson highlands, mercer county in WV and perhaps into the
higher peaks in ashe watauga counties in the afternoon. Those with
outdoor recreation interests should be aware that conditions will be
rather breezy above above 3000 ft tomorrow. Southerly winds in lower
elevations should top out around 15 mph with afternoon gusts to 25-
30 mph. Currently only the 12z nam-12km shows any measure of
precipitation out ahead of the front, but there are enough arguments
against introducing anything higher than slight chance pops
including dry sub-cloud air and light precip rates in conjunction
with the breezy conditions probably making it less likely it'll
actually measure. So, overall an increasingly breezy day with
dewpoints on the rise. Temperatures ranging from the mid 50s to
middle 60s, maybe a spot upper 60 value closer to the nc
piedmont.

Short term tonight through Sunday night
As of 250 pm est Friday...

strong cold front and associated lead shortwave energy still on
track to cross the region Saturday night before quickly exiting by
early Sunday. Models continue to show a swath of showers along and
just behind the boundary overnight which should clear most of the
region prior to daybreak Sunday. Although instability remains limited,
latest progs suggest a bit stronger lift just west of the region
which may allow ongoing shallow convection with thunder to
spill into the far west Saturday evening. Thus included a brief
thunder mention along the west va border, with showers
initially a bit slower to enter the west early on followed by
categorical to likely pops into the early morning hours of
Sunday. Rainfall totals mainly around one half inch west to a
quarter inch or less east.

Again main concern with a surge in wind speeds with the frontal
passage, and then lingering winds within the cold advection
into Sunday as subsequent upper energy crosses from the northwest.

Latest GFS quite impressive with post frontal subsidence per
pressure rises and drying behind the boundary espcly western
sections around midnight and east to the blue ridge shortly
thereafter. This likely enough for advisory levels winds from
the foothills west with possible warning criteria southern blue
ridge into the nc ridges. However given third period and after
coordination with surrounding offices, will hold off on any
headlines for wind at this point, including watches given the
forecast brief nature for higher speeds mainly along the
ridgetops.

Other aspect is with possible snow accumulations over the higher
western elevations given the sharp drop in temperatures as the
strong cold advection arrives into Sunday morning. Appears just
enough residual moisture remaining long enough per forecast raobs
for upslope snow showers to be a bit more widespread espcly
northwest including western greenbrier down to blf. This could
result in an inch or so of snow at higher elevations despite
warm ground conditions. These snow showers flurries likely to
linger through much of Sunday given the passage of the coldest
air aloft under the upper trough. Therefore kept some higher
pops going northwest Sunday morning before slowly tapering
back to mainly flurries by late in the day. Otherwise will be a
windy breezy day under strong northwest winds and chilly
temperatures that wont get out of the 30s far west and 40s to
around 50 elsewhere.

Should see clouds winds diminish during Sunday night in the
wake of the upper system and in advance of high pressure
sliding in from the southwest. With cold air in place under less
gradient and clearing skies will likely see a very cold
overnight with 20s across the board.

Long term Monday through Friday
As of 300 pm est Friday...

upper trough lifts out early Monday allowing high pressure to build
in for early next week under shortwave ridging. This will allow
winds to finally diminish Monday afternoon as the gradient
weakens before heights rise Tuesday resulting in warming
temperatures to more seasonal levels under more Sun light winds.

A more upper level split flow regime looks to develop for the
rest of the week following a weak cold front that will dip
through from the northwest Tuesday night as the pattern unfolds.

Frontal passage looks mainly dry with perhaps more clouds isolated
showers espcly south west into early Wednesday before high
pressure builds in Wednesday afternoon through Friday. This
should result in overall quiet weather with slightly below
normal temperatures through day7.

Aviation 06z Saturday through Wednesday
As of 1230 am est Friday...

vfr conditions will continue through 19z Saturday, then MVFR
conditions with convection will enter the forecast area. Look for
ceilings to fall into the MVFR range late Saturday into
Saturday night as a narrow line of showers convection accompany
the frontal boundary through the region. Until then, ceilings
should mainly beVFR.

Winds will increase from the southwest Saturday as the front
approaches and the large high pressure shifts into the western
atlantic. By afternoon, low end gusts can be expected at most
taf sites. Low-level winds will strengthen considerably during
the later portion of the TAF valid period as a strong 850mb llj
approaches the region with the front. Areas of low-level wind
shear can be expected.

Visibilities will beVFR for the most part, although a brief
period of MVFR-ifr will be possible in heavier rain showers late
Saturday. Will not include any thunder at the TAF sites given
the lack of indicated instability.

Medium confidence in ceilings through the TAF valid period.

Medium to high confidence in visibilities through the TAF valid
period.

High confidence in wind direction and speed through the taf
valid period.

Extended discussion...

a strong cold front moves across the region Saturday night into
Sunday. This will lead to several impacts to aviation,
including a period of rain changing to mountain snow showers
(possible -shsn at bluefield) and a frontal wind shift to
northwest with wind gusts further increasing areawide. Best
chance at sub-vfr conditions is Saturday night into Sunday.

For Sunday, may see a continuation of sub-vfr stratus in the
western appalachians, with breezy gusty northwesterly wind
conditions areawide also continuing. May see mountain snow
showers coming to an end later Sunday afternoon.

Northwesterly winds finally abate by late Sunday evening.

Conditions then transition toVFR Monday through Thursday.

Rnk watches warnings advisories
Va... None.

Nc... None.

Wv... None.

Synopsis... Al jh
near term... Al kk
short term... Jh
long term... Jh
aviation... Al kk rab


Weather Reporting Stations
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Roanoke, Roanoke Regional Airport, VA27 mi23 minE 310.00 miPartly Cloudy37°F30°F76%1017 hPa

Wind History from ROA (wind in knots)
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Last 24hrNW7NW4W4NW7CalmW6NW8CalmW4CalmCalmCalmCalmSE3SE5SE3CalmCalmCalmCalmCalmCalmW3E3
1 day agoNE3NE4CalmW4NW17NW14
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2 days agoCalmCalmCalmCalmE3E3CalmNE4CalmCalmE5E4SE5E5SE4CalmSE5CalmCalmCalmCalmCalmCalmCalm

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
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Wind Forecast for Blacksburg, VA (3,6,7,8)
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Ground Weather Radar Station Blacksburg, VA
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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.