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Marine Weather and Tides
Union, WV

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Sunrise 6:40AMSunset 8:09PM Sunday August 19, 2018 10:08 AM EDT (14:08 UTC) Moonrise 2:20PMMoonset 12:00AM Illumination 56% Phase: First Quarter Moon; Moon at 8 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 Union, WV
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location: 37.62, -80.47     debug

Area Discussion for - Blacksburg, VA
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Fxus61 krnk 191335
afdrnk
area forecast discussion
national weather service blacksburg va
935 am edt Sun aug 19 2018

Synopsis
A cold front will become nearly stationary across our region today,
and then lift north as a warm front on Monday in advance of an
approaching area of low pressure. This low pressure will move from
the mid-mississippi valley on Monday into southern quebec by
Wednesday, bringing its associated strong cold front across our region
on Tuesday. A broad area of cooler and drier high pressure will
settle over the region for the second half of the upcoming
week.

Near term through tonight
As of 930 am edt Sunday...

satellite pictures and surface observations showed stratus
lifting and fog dissipating. Visibility will continue to rapidly
improve. Hrrr from SPC indicating thunderstorms will develop
along the southern blue ridge between noon 16z and 2pm 18z.

Isolated thunderstorm in southwest west virginia may reach
bluefield before noon. Otherwise have trimmed back probability
of precipitation for the rest of the morning.

Saturday's cold frontal passage didn't quite have enough
momentum to progress the whole way across the area. It has
become nearly stationary just north of the interstate-64
corridor. Guidance is hinting that it may make an additional
attempt to cross the area today, but any such trend will be
assisted by outflow from the showers and storms that are
forecast to develop across the mountains starting early this
afternoon. A general westerly flow aloft will help limit
convection across the piedmont. Late in the afternoon into the
early evening is when this region will have its best potential
for convection as the front has its best potential of
approaching reaching this area ushered along by the outflow of
the upstream convection.

Unlike Saturday when the vast majority of the region spent most
of the day under a broad shield of precipitation, there will be
breaks within the overcast which will allow for milder
conditions. High temperatures today are expected to range from
the mid 70s to around 80 across the mountains, with low to mid
80s across the piedmont.

With limited movement of the front, and no immediate change in
airmass behind it, low temperatures tonight will be on par with
those expected to be realized this morning. Expect the low to mid
60s across the mountains with mid 60 to near 70 across the piedmont.

Confidence in the above forecast is moderate. The biggest challenge
will be precipitation coverage across the southeast portion of the
area late this afternoon and evening. If there isn't a push
southeast of the cold front, coverage is not expected to be as great
as what will be forecast.

Short term Monday through Wednesday night
As of 445 am edt Sunday...

a strong somewhat negatively tilted upper trough will move
slowly through the region in the tue-wed time frame. This will
be the key focus of this forecast period as it transitions us
from summerlike conditions to more fall like conditions for the
later half of the week.

Monday, we will see the weak front that stalled across the cwa
Sunday lift back north as a warm front in advance of the
approaching front. The combination of this and approaching lift
associated with the upstream trough should be sufficient enough
to support at least scattered showers and thunderstorms. An
isolated storm could become strong and produce heavy rainfall,
but the main concern for strong to severe thunderstorms and
heavy rainfall will be concentrated on Tuesday as the upper
trough and associated cold front drift through the cwa.

Substantial lift and instability will be present with the upper
trough, including 30-35kt LLJ and upper diffluence to begin to
see associated showers thunderstorms late Monday Monday night.

However the best support arrives during peak heating Tuesday
afternoon as the trough and front move into eastern ky WV during
the afternoon. Nonetheless, the best dynamics lift to our
northwest across northern WV pa and this is where many of the
models focus the most concentrated area of thunderstorms,
potentially a qlcs or squall line type event with the
possibility of severe and heavy rainfall. Normally the greatest
concern with this weather system would be severe as opposed to
hydrological, but FFG values remain low in our area and there
are additional chances to add water to the ground prior to
Tuesday and most areas already saw 1-1.5 inches yesterday. So,
hydro will be a concern again especially across the mountains
and along the i-64 corridor, not so much the blue ridge absent
southeast flow. It still appears, however, that the speed of
movement with this activity will be great enough to limit hydro
issues to locations where there is any training of convective
cells with damaging wind gusts and hail being the greater
threat.

To address these two concerns, SPC has outlooked the entire
forecast area for a "marginal" risk of severe Tuesday with a
 "slight" risk just to our north across northern WV and southwest
pa. Meanwhile, wpc has outlooked the mountain areas for a
"slight" risk of excessive rainfall, with a "marginal" risk for
the remainder of the cwa. Will be covering these risks in a
general idss briefing and the hwo ehwo this morning.

By Wednesday, all of the inclement weather will move off to the
northeast u.S. As the upper trough lifts out of the area,
although a few upslope mountain showers will be possible, mainly
across the mountains of eastern wv. It will be a bit breezy
Wednesday, but nothing close to wind advisory criteria. Temperatures
will remain near seasonal normals for highs and above normals
for lows with high humidity through Tuesday, then trend to
slightly below normal levels Wednesday behind the strong cold
front and upper trough as 850mb temperatures also drop into the
+12c to +14c range.

Forecast confidence levels
temperatures - high,
precipitation chances - high,
winds - moderate to high,
thunderstorm threat - moderate,
heavy rain threat - moderate.

Long term Thursday through Saturday
As of 500am edt Sunday...

the cold front will continue toward the southeast u.S. Coast
Thursday and stall in that region. The flow aloft will begin to
relax as the trough moves northeast out of the region and a
broad subtropical ridge building in the central u.S. Noses its
way into the oh tn valley. Meanwhile, cool canadian high
pressure will build south across the ohio valley and then across
the mid atlantic by Thursday night. The high center will slide
northeast into new england for the weekend. Mostly dry
conditions are expected through Friday. Then as we move into the
weekend, return flow, warmer temperatures, and weak ripples in
the mainly westerly upper flow on the north side of the
subtropical ridge will support an increase in orographic and
diurnal convection, thus mainly the mountainous areas at this
point.

Temperature wise, our first taste of fall, with lows dipping
into the 50s at night and highs only in the 70s to near 80
piedmont thu-fri, warming a bit by the weekend to highs mostly
in the lower to mid 80s, except 70s mountains and lows back into
the 60s.

Forecast confidence levels
temperatures - moderate to high,
precipitation chances - moderate,
winds - moderate to highs,
thunderstorm threat - low.

Aviation 14z Sunday through Thursday
As of 750 am edt Sunday...

flight categories are highly variable across the region this
morning in fog and low clouds. This will improve quickly in the
next couple of hours giving way to MVFR-vfr ceilings later in
the day. Visibilities likewise are experiencing similar extreme
swings. Precipitation has dissipated across most of the region,
but some lingering showers still exist near klwb and kblf.

Another round of convection is expected to develop mainly across
the mountains by early afternoon. The precipitation will be
concentrated there the most into the early afternoon, and then
the focus will shift to the piedmont. Coverage will start to
wane by the late evening with coverage remaining greatest across
the southeast section of the forecast area. Flight categories
will be mainlyVFR during the day, except brief sub-VFR under
the stronger showers storms. A return of patchy ifr MVFR fog is
expected across parts of the area heading into the overnight
hours tonight.

Extended discussion...

on Monday, the stalled frontal boundary should start to lift
back north out of north carolina. Thus, more chances of showers
and thunderstorms will continue in the afternoon espcly southern
and western sections. Additionally, the wet ground may allow
some MVFR ifr ceilings and fog during Monday night, especially
in the mountains. The frontal boundary will move northward as a
warm front by Tuesday and keep conditions unsettled with
potential for more organized convection later Tuesday ahead of
the next stronger cold front. By Wednesday, this cold front will
push through the mid atlantic, and high pressure should build
overhead by Thursday. Good flying weather will return once the
cooler and drier air mass associated with this area of high
pressure arrives.

Rnk watches warnings advisories
Va... None.

Nc... None.

Wv... None.

Synopsis... Ds
near term... AMS ds
short term... Rab
long term... Kk rab
aviation... Ds jh rab

Weather Reporting Stations
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Lewisburg / Greenbrier, WV18 mi73 minN 010.00 miOvercast69°F67°F93%1017.3 hPa

Wind History from LWB (wind in knots)
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Last 24hrCalmCalmCalmCalmCalmW4SW3SW5SW4CalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalm
1 day agoS3SW5W6W4SW8W6W5W6W3CalmN3CalmCalmN3CalmCalmCalmCalmW3CalmCalmCalmCalmCalm
2 days agoCalmCalmS3SW5SW7W6SW6W4CalmNE4N5CalmCalmCalmCalmCalmNE3NE3CalmCalmCalmCalmCalmCalm
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.
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Other links: Northern Pacific     Contential US     Full GOES-East
Wind Forecast for Blacksburg, VA (10,2,3,4)
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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.