Monday, November20, 2017 L-36.com


Marine Weather and Tides
Indian Head, MD

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 6:56AMSunset 4:53PM Monday November 20, 2017 8:32 AM EST (13:32 UTC) Moonrise 8:37AMMoonset 6:46PM Illumination 3% 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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ANZ535 Tidal Potomac From Key Bridge To Indian Head- 631 Am Est Mon Nov 20 2017
.small craft advisory in effect until 10 am est this morning...
.small craft advisory in effect from Tuesday morning through Tuesday afternoon...
Today..SW winds 5 to 10 kt with gusts to 20 kt. Waves 1 ft.
Tonight..S winds 5 to 10 kt. Waves 1 ft.
Tue..SW winds 10 kt with gusts to 20 kt. Waves 1 ft.
Tue night..SW winds 5 to 10 kt. Waves 1 ft. A chance of showers.
Wed..NW winds 5 to 10 kt with gusts to 20 kt. Waves 1 ft.
Wed night..N winds 5 to 10 kt. Waves 1 ft.
Thu..W winds around 5 kt. Waves 1 ft.
Fri..S winds around 5 kt. Waves 1 ft.
ANZ500 631 Am Est Mon Nov 20 2017
Synopsis for the tidal potomac and md portion of the chesapeake bay.. High pressure will build to our south through tonight. The high will move offshore Tuesday and a cold front will pass through late Tuesday night into Wednesday. High pressure will return for the second half of the week. A small craft advisory may be needed for portions of the waters Tuesday night through Wednesday night.

7 Day Forecast for Marine Location Near Indian Head, MD
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location: 38.62, -77.2     debug


Area Discussion for - Baltimore, MD/Washington
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Fxus61 klwx 200812
afdlwx
area forecast discussion
national weather service baltimore md washington dc
312 am est Mon nov 20 2017

Synopsis
High pressure will build to our south through tonight. The high
will move offshore Tuesday and a cold front will pass through
Tuesday night into Wednesday. High pressure will build back
overhead later Wednesday through thanksgiving day. The high will
build to our south for Friday and Saturday before a cold front
moves through Saturday night.

Near term through tonight
Upper-level trough overhead early this morning is beginning to
shift to our east while surface high pressure builds to the
south. Rising heights will continue to cause any stratocu along
the mountains and northern portions of the CWA to dissipate
throughout this morning. Plenty of sunshine is expected this
afternoon and it will turn out a bit milder this afternoon... But
temps will still be below average for this time of year. Max
temps will range from the upper 30s along the ridges of the
allegheny highlands... To the mid and upper 40s in northern
maryland... To the middle 50s in central virginia.

The high will remain to the south tonight. A weak shortwave in
a southwest flow aloft may bring a few high clouds... But dry
conditions will persist. Min temps will range from the mid and
upper 20s in the colder valleys to the mid and upper 30s in
downtown washington and baltimore.

Short term Tuesday through Wednesday night
High pressure will shift offshore Tuesday while a cold front
moves through the great lakes. A southwest flow in between these
systems will allow for milder conditions. MAX temps will be in
the upper 50s to lower 60s across most locations. There will be
some high clouds in a southwest flow aloft... But the cloud deck
should be thin enough for a partly to mostly sunny sky much of
the day.

The cold front will approach our area from the north and west
Tuesday evening before passing through overnight Tuesday into
early Wednesday morning. There will be separation between the
lift associated with the cold front and deeper moisture to our
south and east. Latest guidance shows that some of this moisture
can get drawn up into the front... Bringing the chance for
showers. The best chance for showers will be across eastern
areas where moisture has a better chance to move in before the
frontal passage.

Any showers early Wednesday morning should dissipate as the cold
front moves off to the south and east. A northwest flow will
cause chillier conditions despite increasing sunshine. High
pressure will settle overhead and it will turn out dry and cold.

Did also want to note that a few snow showers are possible along
and west of the allegheny front Tuesday night into early
Wednesday. However... As discussed earlier moisture should be
limited so any accumulation would be light.

Long term Thursday through Sunday
Longwave western us ridging and east coast troughing will
continue to dominate the weather pattern over the united
states through the holiday weekend. While no significant storm
systems are currently forecast, several upper level impulses
will move through the large-scale troughing.

Sprawling surface high pressure is expected to be in place on
thanksgiving day from the southern plains extending northeastward
through the appalachians. At the same time, weak shortwave
energy in both the northern and southern branches of the jet
stream will be moving towards the east coast and may lead to
surface cyclogensis off the southeastern us coastline. At this
time, the surface ridging and flow aloft is expected to keep
anything that can develop well to our south and east, leading to
a dry and uneventful weather forecast for thanksgiving day.

Surface ridging is expected to persist into Friday as well,
keeping the forecast dry.

By Friday night and Saturday, a more potent northern stream
system will move into the upper midwest, with its associated
cold front barrelling towards the mid-atlantic Saturday night.

Once again, southern stream energy will be present as well near
the southeastern states, and the potential exists for surface
cyclogenesis to occur. At this time, fast flow aloft and
orientation of upper level trough suggests that a track well
offshore is favored. However, chances for rain showers increase,
either with the offshore low or with the cold front itself.

Following the front Sunday, blustery and colder conditions are
likely, along with the potential for snow showers over the
higher terrain.

Temperatures will start out below normal on thanksgiving (40s),
moderate back towards normal or even a bit above for Friday and
Saturday (50s), before falling back below for Sunday (40s).

Aviation 08z Monday through Friday
West to northwest winds are gusting around 20 to 25 knots early
this morning due to cold advection and a weak pressure surge. Do
think that there can be a break in the gusts for a few hours
between about 09 and 12z as the surge weakens a bit... But
confidence is low. Winds will gradually turn to the west this
morning and southwest this afternoon. Gusts around 15 to 20
knots this morning should gradually dissipate this afternoon.

Vfr conditions will persist for tonight through Tuesday.

Southwest winds Tuesday will gust around 20 knots in the
afternoon. A cold front will pass through Tuesday night into
early Wednesday. A few showers are possible along with subvfr
cigs. The best chance for this will be across the eastern
terminals.VFR conditions will return behind the cold front for
later Wednesday through Wednesday night.

Vfr and light winds expected Thursday and Friday with surface high
pressure

Marine
West to northwest winds early this morning will gradually turn
to the west later this morning and southwest this afternoon.

Wind gusts should gradually diminish throughout the day. Will
continue with a small craft advisory for the waters through
mid-morning and for the bay and lower tidal potomac river
through this afternoon. The SCA may be able to be cancelled
early across the middle portions of the bay and lower tidal
potomac river this afternoon.

High pressure to our south tonight will move offshore Tuesday.

South to southwest winds will increase during this time ahead of
the next cold front. A small craft advisory is in effect for the
middle portion of the bay and lower tidal potomac river tonight
and for all the waters Tuesday. The SCA may need to be extended
into Tuesday evening for portions of the waters.

A cold front will pass through the waters late Tuesday night
into Wednesday morning. Northwest winds will pick up behind the
front and an SCA may be needed for portions of the waters later
Wednesday into Wednesday night.

Sub-sca conditions expected Thursday and Friday with surface
high pressure.

Lwx watches warnings advisories
Dc... None.

Md... None.

Va... None.

Wv... None.

Marine... Small craft advisory until 6 pm est this evening for
anz530>534-537>543.

Small craft advisory from 9 pm this evening to 6 pm est
Tuesday for anz531>534-537-539>541-543.

Small craft advisory from 10 am to 6 pm est Tuesday for anz530-
535-536-538-542.

Small craft advisory until 10 am est this morning for anz535-
536.

Synopsis... Bjl
near term... Bjl
short term... Bjl
long term... Mm
aviation... Bjl mm
marine... Bjl mm


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
WASD2 - 8594900 - Washington, DC 20 mi45 min W 7 G 11 40°F 48°F1022.7 hPa
NCDV2 22 mi51 min Calm G 1.9 39°F 51°F1021.4 hPa
BSLM2 - Chesapeake Bay, MD 28 mi63 min WNW 2.9 38°F 1021 hPa22°F
44062 - Gooses Reef, MD 42 mi33 min NW 16 G 19 42°F 53°F1 ft1023.4 hPa (+5.2)
TPLM2 - Thomas Point, MD 45 mi33 min W 13 G 15 40°F 53°F
SLIM2 - 8577330 - Solomons Island, MD 45 mi51 min NW 8 G 13 41°F 54°F1021.8 hPa
COVM2 - 8577018 - Cove Point LNG Pier, MD 46 mi45 min NW 9.9 G 13 40°F 1022.7 hPa
44063 - Annapolis 46 mi33 min WNW 9.7 G 16 40°F 52°F1021.9 hPa (+3.3)
APAM2 - 8575512 - Annapolis, MD 46 mi45 min 42°F 1021.3 hPa
PPTM2 - 8578240 - Piney Point, MD 49 mi45 min N 14 G 16

Wind History for Washington, DC
(wind in knots)    EDIT      (on/off)   Help
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NW14
G28
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NW16
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G25
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G22
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G27
NW7
G20
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S12
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N6
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G15
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E1
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G11

Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Fort Belvoir, VA8 mi37 minNW 510.00 miFair39°F18°F44%1023 hPa
Manassas, Manassas Regional Airport/Harry P. Davis Field, VA18 mi37 minN 010.00 miFair32°F25°F75%1024 hPa
Washington/Reagan National Airport, DC, VA19 mi41 minWNW 810.00 miA Few Clouds40°F19°F45%1022.7 hPa
Stafford, Stafford Regional Airport, VA20 mi58 minNNW 410.00 miFair28°F26°F94%1023.7 hPa
Camp Springs / Andrews Air Force Base, MD23 mi37 minWNW 1010.00 miFair38°F19°F46%1022.9 hPa

Wind History from DAA (wind in knots)
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Last 24hrNW19
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NW14
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W10NW8W5NW5NW8NW7NW7NW7NW7NW9
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W8W6W6NW5
1 day agoS7S9
G15
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S9SE5SE5SE6S5S9
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2 days agoNW11
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NW10NW9
G15
NW7NW9NW6NW7CalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmSE3SE3SE6

Tide / Current Tables for High Point, Occoquan Bay, Virginia
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High Point
Click for Map
Mon -- 02:29 AM EST     0.01 feet Low Tide
Mon -- 06:56 AM EST     Sunrise
Mon -- 08:07 AM EST     1.51 feet High Tide
Mon -- 08:37 AM EST     Moonrise
Mon -- 02:17 PM EST     0.05 feet Low Tide
Mon -- 04:52 PM EST     Sunset
Mon -- 06:46 PM EST     Moonset
Mon -- 08:13 PM EST     1.69 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
0.50.2000.30.71.11.41.51.41.10.70.40.20.10.10.40.81.31.61.71.61.31

Tide / Current Tables for Marshall Hall, Potomac River, Maryland
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Marshall Hall
Click for Map
Mon -- 03:05 AM EST     -0.02 feet Low Tide
Mon -- 06:56 AM EST     Sunrise
Mon -- 08:36 AM EST     Moonrise
Mon -- 09:06 AM EST     2.22 feet High Tide
Mon -- 02:53 PM EST     0.04 feet Low Tide
Mon -- 04:51 PM EST     Sunset
Mon -- 06:46 PM EST     Moonset
Mon -- 09:12 PM EST     2.48 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
10.60.2-00.10.61.21.72.12.221.50.90.40.100.20.71.31.92.32.52.41.9

Weather Map and Satellite Images
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Weather Map
wmap_A
IR Satellite Image from GEOS
east_satellite

GOES Local Image of Mid-Atlantic    EDIT
Geos

Wind Forecast for Baltimore, MD/Washington (8,2,3,4)
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Ground Weather Radar Station Sterling, VA
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weather_mapweather_map weather_map

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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.