Tuesday, May21, 2019 L-36.com


Marine Weather and Tides
Mount Vernon, VA

Version 3.4
What's New / NOTES
10/6/2018 Colors of tide XTide graphs changed to emphasize that they were upgraded. See next note. Comments welcome.
10/4/2018 I have fixed XTide and updated the harmonic files. There were some name changes so you might have to click EDIT to find the new station name.

Sunrise 5:50AMSunset 8:20PM Tuesday May 21, 2019 10:33 PM EDT (02:33 UTC) Moonrise 10:12PMMoonset 7:06AM Illumination 90% Phase: Waning Gibbous; Moon at 18 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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ANZ535 Tidal Potomac From Key Bridge To Indian Head- 737 Pm Edt Tue May 21 2019
Tonight..N winds 5 to 10 kt. Waves 1 ft.
Wed..SE winds 5 kt. Waves less than 1 ft.
Wed night..S winds 5 kt. Waves less than 1 ft.
Thu..SW winds 5 to 10 kt. Waves 1 ft. A chance of showers and tstms.
Thu night..W winds 5 kt. Waves less than 1 ft. A chance of showers and tstms.
Fri..NW winds 5 to 10 kt with gusts to 20 kt. Waves 1 ft.
Fri night..NE winds 5 to 10 kt. Waves 1 ft.
Sat..SW winds 5 kt. Waves less than 1 ft.
Sun..NW winds around 5 kt. Waves 1 ft. A chance of showers through the night. Winds and waves higher and visibilities lower in and near tstms.
ANZ500 737 Pm Edt Tue May 21 2019
Synopsis for the tidal potomac and md portion of the chesapeake bay.. High pressure will build overhead through tonight before moving offshore Wednesday. A warm front will approach the waters Wednesday night before passing through Thursday. A cold front will stall out near the waters late this week. A small craft advisory may be needed for portions of the waters late Wednesday night through Friday.


7 Day Forecast for Marine Location Near Mount Vernon, VA
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location: 38.68, -77.1     debug


Area Discussion for - Baltimore, MD/Washington
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Fxus61 klwx 220119
afdlwx
area forecast discussion
national weather service baltimore md washington dc
919 pm edt Tue may 21 2019

Synopsis
Canadian high pressure will build overhead through tonight
before moving offshore Wednesday. A warm front will pass through
the area Wednesday night into Thursday. A cold front will
approach Thursday night before stalling out nearby for Friday
and Saturday. The boundary may hang around nearby for the rest
of the weekend into early next week, causing the possibility of
unsettled conditions.

Near term through Wednesday
Canadian high pressure will continue to build overhead through
tonight bringing cool conditions for this time of year along
with low humidity. There will be some high clouds moving through
in the westerly flow aloft, but with the upper-level ridge axis
to our west... The cloud deck should be thin due to subsidence.

Min temps tonight range from the 40s in the colder valleys and
rural areas to the mid upper 50s in downtown washington and
baltimore.

Short term Wednesday night through Thursday night
The high will slowly move offshore Wednesday and a southerly
flow will develop during the afternoon. There will be a slight
increase in atmospheric moisture due to the southerly flow and
warm advection. This may result in a thin stratocu deck
underneath the subsidence inversion, but there should still be
plenty of sunshine as well since the thin layer should mix out
from daytime heating. MAX temps will be in the lower to middle
70s for most locations.

The high will continue to move offshore Wednesday night and a
warm front is expected to approach the area from the west
overnight. The warm front will pass through the region Thursday
morning. Weak isentropic lift and limited elevated instability
ahead of the warm front may be enough to trigger a few showers,
especially overnight Wednesday into Thursday morning. A rumble
of thunder cannot be ruled out as well, but confidence is low at
this point since the lifting mechanism will be weak.

For Thursday afternoon, a southwest flow behind the warm front
will bring a return to hotter and more humid conditions. Max
temps will top off well into the 80s for most areas, and some
areas may even approach 90 degrees. The increased heat and
humidity will lead to an unstable atmosphere, and with our area
between an upper-level high to the south and upper-level low to
the north, there should be moderate amounts of deep layer shear.

At the same time, a cold front will be approaching from the
north but latest guidance keeps this boundary well to our north
during peak heating before it drops down later Thursday night.

Therefore, the timing of the boundary and peak heating are
offset a bit. Having that been said, it will be a differential
advection pattern (northwest flow aloft and southwest flow at
the low-levels), which supports the development of convective
systems (mcs). Will carry the chance for showers and
thunderstorms Thursday afternoon and evening, and with the
instability and shear in place, some of those storms could be
severe. However, confidence still remains low due to uncertainty
in timing of a convective system and also with the cold front
arrival being after peak heating.

The boundary will settle overhead late Thursday night, and a
shower is possible, but most areas will likely be dry due to the
loss of heating.

Long term Friday through Tuesday
Upper level ridging will remain centered over the southeastern
Friday and Saturday. Meanwhile, a cold front will be located
near or south of the area Friday. With ridging shunted to the
west, this should lead to slightly cooler and less humid
conditions. A narrow ridge of surface high pressure will move
overhead Friday night.

A low pressure system will be moving north of the great lakes on
Saturday. The system's warm sector will translate eastward
through the day, although there's some uncertainty if the upper
ridge will remain strong enough to suppress any convection. The
best chance of any showers and storms will be over the terrain
and closer to the pennsylvania border. The shortwave trough
aloft will suppress the ridge to the south, resulting in a more
zonal flow aloft across the mid atlantic for the second half of
the weekend. This will slow the cold front's southward progress
and allow it to waver across the area into early next week. This
will result in mainly diurnal chances of showers and
thunderstorms Sunday into Monday. There's some consensus on
another shortwave being able to shove the front south by
Tuesday, with high pressure to follow (briefly). With the
absence of any strong pushes of canadian air, temperatures will
likely run above normal through early next week.

Aviation 01z Wednesday through Sunday
Vfr conditions are expected through Wednesday under light flow.

A few showers are possible overnight Wednesday into Thursday
morning, and an isolated thunderstorm cannot be ruled out but
confidence is low.

There is a chance for thunderstorms Thursday afternoon and
evening, and if storms develop they have the potential to become
severe. However, confidence remains low at this time.

High pressure will provideVFR conditions for Friday and much of
Saturday. A stray shower or thunderstorm is possible by Saturday
and Sunday afternoons, with the highest chance near mrb at this
time.

Marine
Winds have diminished below criteria this evening. There may be
a brief pressure surge overnight into early Thursday morning
and winds from the northeast may gust close to SCA criteria
across the middle portion of the bay. However, confidence is
too low for an SCA at this point.

Southerly winds will develop around the departing high
Wednesday. A warm front will pass through the water late
Wednesday night through Thursday morning before another cold
front from the north stalls out near the waters Friday. A small
craft advisory may be needed for portions of the waters late
Wednesday night through Friday.

Strong to perhaps severe thunderstorms are possible Thursday
afternoon into Thursday evening, but confidence for them to
occur is low at this time.

Northwest winds behind a cold front may result in SCA conditions
on Friday. High pressure will bring lighter winds Friday night
before turning southwesterly Saturday. Another cold front will
approach on Sunday, with wind direction and speeds of lower
confidence due to its slow movement. A stray thunderstorm could
also occur during this time.

Lwx watches warnings advisories
Dc... None.

Md... None.

Va... None.

Wv... None.

Marine... None.

Synopsis... Bjl
near term... Bjl imr
short term... Bjl
long term... Ads
aviation... Bjl ads imr
marine... Bjl ads imr


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
WASD2 - 8594900 - Washington, DC 14 mi40 min NNW 4.1 G 7 69°F 69°F1019.5 hPa
NCDV2 25 mi40 min NW 1.9 G 2.9 66°F 73°F1018.6 hPa
44062 - Gooses Reef, MD 37 mi46 min NNW 9.7 G 12 67°F 1019.8 hPa
TPLM2 - Thomas Point, MD 38 mi34 min NW 7 G 8 66°F 67°F1020.3 hPa (+2.0)46°F
APAM2 - 8575512 - Annapolis, MD 39 mi40 min 65°F 1018.8 hPa
44063 - Annapolis 40 mi40 min NNW 5.8 G 7.8 67°F 67°F1019.3 hPa
COVM2 - 8577018 - Cove Point LNG Pier, MD 42 mi40 min N 15 G 16 67°F 1019.9 hPa
SLIM2 - 8577330 - Solomons Island, MD 42 mi40 min N 8 G 8.9 67°F 69°F1018.9 hPa
CPVM2 44 mi40 min 66°F 47°F
FSKM2 - 8574728 - Francis Scott Key Bridge, MD 48 mi40 min NW 8 G 8 69°F 1019.3 hPa
FSNM2 48 mi40 min WNW 7 G 8 68°F 1019.2 hPa
PPTM2 - 8578240 - Piney Point, MD 48 mi40 min NNE 6 G 7
BLTM2 - 8574680 - Baltimore, MD 49 mi40 min N 4.1 G 7 68°F 71°F1019 hPa

Wind History for Washington, DC
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Fort Belvoir, VA5 mi98 minNW 410.00 miPartly Cloudy66°F44°F46%1019.2 hPa
Washington/Reagan National Airport, DC, VA13 mi42 minN 710.00 miMostly Cloudy65°F44°F47%1019.5 hPa
Camp Springs / Andrews Air Force Base, MD16 mi98 minN 510.00 miOvercast66°F42°F42%1019.2 hPa
Quantico Marine Corps Airfield - Turner Field, VA16 mi98 minN 510.00 miOvercast69°F45°F42%1019.2 hPa
Manassas, Manassas Regional Airport/Harry P. Davis Field, VA22 mi38 minNNE 610.00 miPartly Cloudy66°F45°F47%1020.8 hPa
College Park Airport, MD23 mi51 minN 010.00 miFair60°F46°F61%1019.3 hPa

Wind History from DAA (wind in knots)
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1 day agoS4S5SE4SE6SE3S4S6SW4CalmCalmSW5W6SW6S5S8SW8SW8
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2 days agoCalmCalmCalmNE4SE5SE4CalmCalmCalmCalmSE4SE3SW4SE5S3S7SE6SE8SE7S9S6S4S4S4

Tide / Current Tables for Marshall Hall, Maryland
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Marshall Hall
Click for Map
Tue -- 04:20 AM EDT     0.26 feet Low Tide
Tue -- 05:51 AM EDT     Sunrise
Tue -- 08:06 AM EDT     Moonset
Tue -- 10:31 AM EDT     2.91 feet High Tide
Tue -- 05:11 PM EDT     0.11 feet Low Tide
Tue -- 08:18 PM EDT     Sunset
Tue -- 11:11 PM EDT     Moonrise
Tue -- 11:12 PM EDT     2.50 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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21.40.90.50.30.30.71.42.12.62.92.92.51.91.30.80.40.10.20.71.31.92.32.5

Tide / Current Tables for High Point, Occoquan Bay, Virginia
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High Point
Click for Map
Tue -- 03:42 AM EDT     0.18 feet Low Tide
Tue -- 05:52 AM EDT     Sunrise
Tue -- 08:07 AM EDT     Moonset
Tue -- 09:31 AM EDT     2.00 feet High Tide
Tue -- 04:33 PM EDT     0.08 feet Low Tide
Tue -- 08:18 PM EDT     Sunset
Tue -- 10:12 PM EDT     1.72 feet High Tide
Tue -- 11:12 PM EDT     Moonrise
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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1.10.70.40.20.20.40.91.41.8221.71.410.60.40.10.10.40.81.31.61.71.6

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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Wind Forecast for Baltimore, MD/Washington (22,6,7,8)
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Ground Weather Radar Station Sterling, 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.