Tuesday, July17, 2018 L-36.com


Marine Weather and Tides
Indian Head, MD

Version 3.4
What's New / NOTES
5/20/2018 -- NOAA is having problems with the data feed that I use to draw the graphs. They are aware of the issue and working to resolve it. Sometimes changing the location by about a mile will give a correct graph. 3/3/2018 - There is a new GOES Satellite for the east coast that required rewriting that part of the code. Please report any issues.

Sunrise 5:57AMSunset 8:32PM Tuesday July 17, 2018 1:33 AM EDT (05:33 UTC) Moonrise 10:09AMMoonset 10:56PM Illumination 18% Phase: Waxing Crescent; Moon at 4 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- 1031 Pm Edt Mon Jul 16 2018
Rest of tonight..S winds 5 kt. Waves less than 1 ft. A slight chance of showers and tstms. Vsby 1 nm or less.
Tue..SW winds 5 kt. Waves less than 1 ft. Showers likely with a chance of tstms.
Tue night..NW winds 5 kt. Waves less than 1 ft. A chance of showers and tstms.
Wed..NW winds 5 kt. Waves less than 1 ft.
Wed night..N winds around 5 kt. Waves 1 ft or less.
Thu..NE winds around 5 kt. Waves 1 ft.
Thu night..SE winds around 5 kt. Waves 1 ft.
Fri..SE winds around 5 kt. Waves 1 ft.
Sat..SE winds 5 to 10 kt. Waves 1 ft. A chance of showers and tstms. Winds and waves higher and visibilities lower in and near tstms.
ANZ500 1031 Pm Edt Mon Jul 16 2018
Synopsis for the tidal potomac and md portion of the chesapeake bay.. High pressure will remain over the atlantic through tonight. A cold front will approach the waters Tuesday before passing through Tuesday night. High pressure will build overhead Wednesday through Thursday before moving offshore Friday. A small craft advisory may be needed for portions of the waters Wednesday.

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 170135
afdlwx
area forecast discussion
national weather service baltimore md washington dc
935 pm edt Mon jul 16 2018

Synopsis
High pressure will remain over the atlantic through tonight. A
cold front will approach the area Tuesday before passing through
Tuesday night. High pressure will return for Wednesday and
Thursday before moving offshore Friday. Low pressure may impact
the area during the weekend.

Near term through Tuesday
Showers and thunderstorms have dissipated this evening and party
cloudy to mostly clear skies are observed. Southerly to
southwesterly flow will keep muggy conditions overnight, and
lows will range in the 70s area wide, with upper 70s likely
along and east of the i- 95 corridor.

Short term Tuesday night through Wednesday night
Surface cold front upper trough axis will be approaching the
mountains Tuesday morning, and crossing the area during the day.

Most guidance solutions suggest that the front will be near the
i-95 corridor by 00z, suggesting that the afternoon hours will
be the most active. Sufficient instability will be able to
stream north ahead of the front. However, the slightly earlier
timing and better forcing north of the area should preclude
numerous damaging wind gusts. Nonetheless, enough low level
convergence lift present for likely pops beginning late morning.

Believe that the forcing mechanisms, and thus thunderstorms,
will be pushing east of the bay Tuesday evening. Have refined
the timing forecast for storms, which now features dry weather
after midnight. Lower dewpoints will be advecting southeast
overnight, and this will continue through Wednesday as high
pressure builds from the great lakes. Wednesday's highs will be
upper 70s-mid 80s, with dewpoints around 60f.

Long term Thursday through Monday
High pressure will move overhead on Thursday, before progressing off
the atlantic seaboard on Friday. This will result in two days of dry
weather and well below normal humidity levels. Dewpoints will run in
the 50s on Thursday, and low-mid 60s on Friday. Temperatures should
be near to slightly below normal for this time of year, with highs
in the mid-upper 80s.

By the weekend, a potent upper-level low is expected to approach
from the great lakes. Model guidance differs fairly substantially on
the evolution of the smaller scale details associated with this
feature, but pretty much all guidance has this system impacting our
area. It appears as though showers and thunderstorms are a good bet
both days this weekend, with Sunday likely having the higher areal
coverage and intensity of storms.

Aviation 01z Tuesday through Saturday
Showers and thunderstorms have dissipated this evening with
scattered to a few clouds over the terminals. Believe there
will be enough residual cloud cover to preclude fog development
tonight.

Showers thunderstorms will be more numerous Tuesday, possibly
beginning as soon as late morning... Especially for mrb, and then
gradually cross the terminals. The back edge should push east
late afternoon... Perhaps early evening for dca bwi mtn. While it
won't be raining the whole time (probably less than 50% for the
time), flight restrictions as well as gusty winds possible
within any storm. Have opted not to include many restrictive
details in the TAF at this time due to confidence uncertainties
in specifics.

Vfr conditions are expected Wednesday through Friday with high
pressure in control. Conditions may deteriorate to sub-vfr this
weekend as a system approaches from the great lakes. Thunderstorms
will be possible both Saturday and Sunday afternoon.

Marine
Southerly flow has increased this evening and and is expected to
continue overnight. A small craft advisory is in effect through
early Tuesday morning for the mid bay lower potomac.

A cold front will approach and cross the waters Tuesday
afternoon, with showers and thunderstorms expected to impact
the waters. Some storms could be strong, producing gusty winds
and the need for special marine warnings. May also have a south
surge ahead of the front, but mixing remains questionable. Have
opted to keep winds below small craft thresholds. Similarly,
winds turn northwest behind the front. Have better confidence in
reaching 20 kt gusts Wednesday, so no small craft advisory at
this time.

A couple of days of high pressure Thursday through Friday would
support light(er) winds. Low end SCA winds may be possible on
Saturday and Sunday as a system approaches from the great lakes.

Thunderstorms will also be possible both Saturday and Sunday.

Tides coastal flooding
Water levels remain about one-half to three-quarters of a foot
above astronomical normals. Slightly elevated water will
continue for the next several cycles. However, do not believe
that tides will exceed caution stage.

Lwx watches warnings advisories
Dc... None.

Md... None.

Va... None.

Wv... None.

Marine... Small craft advisory until 9 am edt Tuesday for anz532>534-537-
540-541-543.

Synopsis... Bkf hts
near term... Imr hts
short term... Bkf hts
long term... Kjp
aviation... Imr hts kjp
marine... Imr hts kjp
tides coastal flooding... Hts


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
WASD2 - 8594900 - Washington, DC 20 mi33 min S 6 G 8.9 80°F 84°F1013.4 hPa (+0.0)
NCDV2 22 mi33 min SSW 7 G 8.9 80°F 85°F1012.7 hPa (-0.6)
BSLM2 - Chesapeake Bay, MD 28 mi123 min Calm 76°F 1014 hPa73°F
44062 - Gooses Reef, MD 42 mi33 min SSW 12 G 14 82°F 1 ft1014.1 hPa (+0.0)
TPLM2 - Thomas Point, MD 45 mi33 min S 12 G 14 81°F 80°F1014.4 hPa (+0.0)76°F
SLIM2 - 8577330 - Solomons Island, MD 45 mi33 min S 8 G 11 81°F 82°F1013.7 hPa (-0.4)
COVM2 - 8577018 - Cove Point LNG Pier, MD 46 mi33 min SSW 11 G 14 81°F 1014.5 hPa (+0.0)
APAM2 - 8575512 - Annapolis, MD 46 mi33 min 82°F 1012.9 hPa (+0.0)
44063 - Annapolis 47 mi33 min SW 12 G 14 82°F 82°F1 ft1013.7 hPa (+0.0)

Wind History for Washington, DC
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Fort Belvoir, VA8 mi97 minN 010.00 miMostly Cloudy75°F71°F89%1013.8 hPa
Quantico Marine Corps Airfield - Turner Field, VA9 mi37 minSSW 510.00 miFair79°F72°F79%1013.9 hPa
Manassas, Manassas Regional Airport/Harry P. Davis Field, VA18 mi37 minN 010.00 miFair71°F70°F96%1014.4 hPa
Washington/Reagan National Airport, DC, VA19 mi41 minS 710.00 miMostly Cloudy81°F72°F74%1013.5 hPa
Stafford, Stafford Regional Airport, VA20 mi38 minSSE 310.00 miFair75°F75°F100%1014.9 hPa
Camp Springs / Andrews Air Force Base, MD23 mi97 minN 010.00 miFair76°F69°F78%1013.9 hPa

Wind History from DAA (wind in knots)
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Last 24hrCalmCalmCalmCalmCalmCalmCalmE4CalmW3S5SE4SE6S7S8W13
G24
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1 day agoCalmSE3CalmCalmSE4CalmCalmSW4S4S3CalmS4CalmSE4SE5S4CalmCalmCalmCalmCalmCalmCalmCalm
2 days agoCalmCalmCalmCalmCalmCalmCalmSW3S6S4S6S9S7S6SW8SE8S6SE5SE4CalmSE3SE3SE3SE3

Tide / Current Tables for High Point, Occoquan Bay, Virginia
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High Point
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Tue -- 05:30 AM EDT     0.06 feet Low Tide
Tue -- 05:58 AM EDT     Sunrise
Tue -- 11:09 AM EDT     1.92 feet High Tide
Tue -- 11:09 AM EDT     Moonrise
Tue -- 05:59 PM EDT     -0.04 feet Low Tide
Tue -- 08:31 PM EDT     Sunset
Tue -- 11:46 PM EDT     1.87 feet High Tide
Tue -- 11:56 PM EDT     Moonset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
1.71.310.60.30.10.10.40.91.41.81.91.81.51.10.70.40.1-00.10.61.11.61.8

Tide / Current Tables for Marshall Hall, Potomac River, Maryland
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Marshall Hall
Click for Map
Tue -- 05:57 AM EDT     Sunrise
Tue -- 06:10 AM EDT     0.09 feet Low Tide
Tue -- 11:08 AM EDT     Moonrise
Tue -- 12:10 PM EDT     2.75 feet High Tide
Tue -- 06:39 PM EDT     -0.04 feet Low Tide
Tue -- 08:31 PM EDT     Sunset
Tue -- 11:56 PM EDT     Moonset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
2.72.41.91.30.80.40.10.20.71.52.12.62.72.62.11.510.50.1-00.311.72.3

Weather Map and Satellite Images
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wmap_A
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.
target = "new">Link to Loop

Other links: Northern Pacific     Contential US     Full GOES-East
Wind Forecast for Baltimore, MD/Washington (1,6,7,8)
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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.