Monday, May29, 2017 L-36.com


Marine Weather and Tides
Union, WV

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 6:02AMSunset 8:36PM Monday May 29, 2017 11:44 PM EDT (03:44 UTC) Moonrise 9:08AMMoonset 11:28PM Illumination 21% Phase: Waxing Crescent; Moon at 5 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
    EDIT      (on/off)   Help
7 Day Forecast for Marine Location Near Union, WV
   Hourly   EDIT   Help
location: 37.62, -80.47     debug


Area Discussion for - Blacksburg, VA
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
Fxus61 krnk 300116
afdrnk
area forecast discussion
national weather service blacksburg va
916 pm edt Mon may 29 2017

Synopsis
A cold front will continue to push southeast of the area
overnight, followed by another front entering from the
northwest Tuesday afternoon. Yet another front passes across
Wednesday, before high pressure builds overhead Thursday.

Near term through Tuesday
As of 855 pm edt Monday...

shallow convection continues to clip far southeast sections
while northward advance has been limited by mid level dry air as
seen off evening soundings and lower surface dewpoints per msas.

Instability has also been rather weak over southern sections so
appears given loss of heating that most added deeper convection
will remain to the south ahead of the weak front now across
southeast sections. Latest hrrr a bit more aggressive in
holding showers in well after midnight espcly far southern
third as the sheared wave aloft seen off the vapor loop crosses
the region overnight. This so far has been overdone so leaning a
bit more toward the drier rap solution in keeping in some low
pops southeast a couple hours after midnight as showers may tend
to string out along the slow boundary. Otherwise not a lot of
change with mainly cloudy skies per extensive mid deck, and
lows 50s mountains to low mid 60s east.

Previous valid discussion as of 300 pm edt Monday...

pops will remain on the low end early this afternoon, with
meager convergence, however, a few showers are popping up and or
moving in from far SW va, with some CU development over the blue
ridge north of the james river.

High-res models still content on keeping focus over nc and south
today with storms becoming more robust by late afternoon
along south of i-40, but some should sneak into our southeast
cwa by 23-01z, so higher pops to 40-60 look good from
yadkinville to south boston. No big chances in the severe threat
with best instability and shear over the piedmont of nc and east
of danville in va, to points east and south.

Drier air should filter into the low levels overnight west of the
blue ridge, but expect slower removal of higher dewpoints to the
east, as frontal boundary stalls from the smokys north georgia to
the coastal plains of nc. Seems we will keep some mid high clouds
across the piedmont overnight with a little clearing to the west.

Lows tonight expected to be similar to this mornings, with mid to
upper 50s west, to lower to mid 60s.

Tuesday, not much change in the airmass, though slightly lower
dewpoints are possible in the higher ridges. Southwest flow aloft
and some weak vorts tracking along it may spark isolated convection
but overall threat expected to be 20 30 pops at most in the
afternoon. Highs will range from the mid to upper 70s mountains, to
mid 80s east.

Short term Tuesday night through Thursday night
As of 145 pm edt Monday...

on Tuesday evening, the passage of a weak surface trough out of
the forecast area should allow for a brief period of dry
weather for the overnight hours. With westerly low-level flow,
the mid- atlantic central appalachians region should remain
removed from higher dewpoints over the central eastern
carolinas. Temperatures should be fairly seasonable with
lowering humidity levels into the 50s to near 60.

Wednesday looks to be the most active day in the mid-week period.

Low-level winds back slightly toward the southwest south-southwest
ahead of a potent mid-level shortwave and associated surface cold
front over the ohio valley. These two features approach the central
appalachians late Wednesday into Wednesday evening. Should start
Wednesday with mostly sunny skies but with increasing cumulus clouds
due to steepening low-level lapse rates and modest moist advection
as winds become more southwesterly. Frontal timing is a little
slower than noted yesterday, moving across the region later
Wednesday afternoon into the mid-evening hours. Relatively strong
500 mb jet of 60 kts contributes to unidirectional though strong
speed shear with effective shear magnitudes of 50 kts. GFS and nam
are at odds on the degree of instability due mainly to potential
daytime mixing of drier dewpoints. Capes range from 1500-1700 j kg
as modeled by 12z NAM using the most unstable parcel while the drier
gfs comes in with CAPE values about half that much. Potential would
exist for an organized scattered strong to severe thunderstorm risk
if the nam's shear instability parameter space proves correct, less
so with the gfs. It is something that will need to carefully
monitored. Current day-3 severe convective outlook depicts a 5%
severe marginal risk from the blue ridge foothills westward, with
general thunder further east. This seems appropriate given
uncertainties as described, though the threat may be slightly higher
if greater instability is realized.

Behind the front, a strong shot of cooler and drier air then advects
into the region late Wednesday night into Thursday. Surface ridge
builds in from the midwest allowing for the first real fully dry day
experienced recently. This should knock temperatures down to highs
in the mid 70s to lower 80s except cooler in the mountains but with
notably drier conditions, and lows Thursday night in the 50s to near
60.

Long term Friday through Monday
As of 100 pm edt Monday...

forecast area then becomes embedded in a zonal, confluent mid-level
flow for a large part of late week into the weekend. This is
modulated by two primary 500 mb features: a persistent mid upper-
level low and cyclonic flow over the northeast great lakes, and
increasing troughing over the four corners leading to greater
southwest flow and warmer more humid conditions from the plains
into the tennessee valley.

Warmer and increasing humidity levels can be expected through the
upcoming weekend, along with a return to a wet weather pattern in a
general sense. Timing weak shortwave troughs vorticity maxima in the
confluent flow is difficult; and as such, i've kept chances for pops
lingering through the upcoming weekend into early next week.

Aviation 01z Tuesday through Saturday
As of 645 pm edt Monday...

weak front over the area along with the arrival of a wave aloft
from the southwest will bring periods of mid deck along with
sct bkn cumulus across southern sections into late this evening.

This should make for mainlyVFR CIGS with potential MVFR around
kdan if any convection to the south lifts farther north. Will
keep in a vcts tempo mix for shra tsra at kdan through at least
midnight as this point. Otherwise rest of terminals should stay
rainfree, though a light shower sprinkle cannot be ruled out,
but nothing to obscure vsbys or lower CIGS belowVFR.

Latest guidance shifts most convection to the southeast well
after midnight with lingering mid deck over the east and some
high clouds over the west. Fog may become an issue mainly over
the east southeast where dewpoints remain higher and espcly
around kdan if some rainfall occurs. Also some late night valley
fog possible over the west. Thus appears a period of MVFR ifr in
fog stratus will be possible espcly at klwb kbcb kdan, but
confidence remains low to medium of seeing much coverage.

Any fog lifts around 13z 9am toVFR and some sct bkn mid clouds
Tuesday morning followed by sct bkn cumulus in the afternoon.

Another front expected by Tuesday afternoon appears to bring
scattered to isolated threat of showers storms to the area, but
will beVFR overall.

Extended aviation discussion...

overallVFR expected for mid and late week before showers and
storms increase later Friday into Saturday. Exceptions will be
any late night river fog, or shower wet ground induced fog.

Next threat of shower storms Wednesday with yet another front
and decent upper support, so will have to watch for stronger
convection but appears any sub-vfr will be brief and mainly over
the mountains.

Thursday looks dry then more potential for scattered afternoon
and evening storms Friday through the weekend with the best
coverage on Saturday when more in the way of sub-vfr will be
possible.

Rnk watches warnings advisories
Va... None.

Nc... None.

Wv... None.

Synopsis... AMS jh wp
near term... Jh wp
short term... Al
long term... Al
aviation... AMS jh wp


Weather Reporting Stations
   EDIT       (on/off)   Help   NOTE: Click on distance to see the station location on a map

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Lewisburg / Greenbrier, WV18 mi70 minN 010.00 miFair61°F57°F87%1018.6 hPa

Wind History from LWB (wind in knots)
-12
PM
1
AM
2
AM
3
AM
4
AM
5
AM
6
AM
7
AM
8
AM
9
AM
10
AM
11
AM
12
PM
1
PM
2
PM
3
PM
4
PM
5
PM
6
PM
7
PM
8
PM
9
PM
10
PM
11
PM
Last 24hrCalmCalmSW3W4W3SW5W5W6W4W5NW6W10
G14
W10
G14
W7W6W7W6SW3CalmW3CalmCalmCalmN3
1 day agoCalmCalmCalmCalmCalmCalmCalmCalmCalmSW5SW3W3CalmSW4SW8W6W5W4NW6W5W3W5W4Calm
2 days agoCalmCalmCalmCalmCalmCalmCalmCalmCalmSW5SW4SW7SW10W8
G14
SW11
G15
W8W8
G15
SW8SW7W3SW5CalmCalmCalm

Tide / Current Tables for
   EDIT   RT Ports Option   Weekend mode (on/off)   (on/off)   Help
Tide / Current Tables for
   EDIT      (on/off)   Help
Weather Map and Satellite Images
       (on/off)   Help
Weather Map
wmap_A
IR Satellite Image from GEOS
east_satellite

GOES Local Image of Mid-Atlantic    EDIT
Geos

Wind Forecast for Blacksburg, VA (23,6,7,8)
      (on/off)   Help

Ground Weather Radar Station Blacksburg, VA
   (on/off)   Help
weather_mapweather_map weather_map

Ad by Google

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.