Tuesday, September26, 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 7:00AMSunset 6:59PM Tuesday September 26, 2017 7:08 AM EDT (11:08 UTC) Moonrise 11:59AMMoonset 10:13PM Illumination 33% Phase: Waxing Crescent; Moon at 6 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- 525 Am Edt Tue Sep 26 2017
Today..NE winds 5 kt. Waves less than 1 ft. Patchy fog this morning with vsby 1 to 3 nm.
Tonight..N winds 5 kt. Waves less than 1 ft.
Wed..N winds 5 to 10 kt. Waves 1 ft.
Wed night..N winds 5 to 10 kt. Waves 1 ft.
Thu..N winds 10 kt. Waves 1 ft.
Thu night..N winds 5 to 10 kt. Waves 1 ft.
Fri..NW winds around 5 kt. Waves 1 ft or less.
Sat..N winds 5 to 10 kt. Waves 1 ft.
ANZ500 525 Am Edt Tue Sep 26 2017
Synopsis for the tidal potomac and md portion of the chesapeake bay.. High pressure will weaken overhead through Wednesday as hurricane maria drifts north to northeast off the north carolina coast. A cold front will pass through the area Thursday and a reinforcing cold front will pass through late Friday into early Saturday. High pressure will return for the weekend. Small craft advisories may be needed Wednesday night and gale force winds are possible Thursday. Small craft advisories may be needed again Friday night into Saturday. Refer to the national hurricane center for up-to-date information on hurricane maria.

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 260809
afdlwx
area forecast discussion
national weather service baltimore md washington dc
409 am edt Tue sep 26 2017

Synopsis
High pressure will slowly weaken its grip over the area today
and Wednesday as hurricane maria stalls in the western
atlantic. A cold front will move through Thursday, bringing
seasonable temperatures from late this week through early next
week. The front will also push hurricane maria out to sea.

Little if any rain is expected through early next week.

Near term through tonight
Maria is hanging off the nc coast this morning, but the wind
field has expanded enough such that an easterly flow is
strenghtening over our region. Some low clouds are trying to
move into the region from the ocean. Further west, we have
patchy fog in the more interior areas. High pressure to our
north is weaker today, and with the stronger easterly flow,
temperatures today should be a little cooler than yesterday,
though we do expect most of the clouds and fog to burn off.

Highs mainly 80s. A few showers could reach southern md, but
most likely they stay southeast.

Tonight, maria will remain off the nc coast. A few showers may
reach southern md, but again, odds are not high. We could see
more clouds advect in as well from the east, while inland could
see more patchy fog. All in all, not much different from what
we've seen lately. Lows mainly in the 60s.

Short term Wednesday through Thursday night
Maria will start turning east away from the region late
Wednesday, so we will still see some clouds especially in
eastern areas from it on Wednesday, and perhaps a stray shower
in southern md. Otherwise, we likely end up a bit warmer
Wednesday as clouds should overall be reduced as the storm
begins turning out to sea. Highs mainly 80s, but a few degrees
above today.

Strong cold front moves in early Thursday, with a pretty strong
breeze expected. However, with limited moisture and dynamics,
don't expect any showers with the front at this time. Humidity
will lower and highs may actually fail to reach 80 for the first
time in quite a few days. Skies will turn out mostly sunny.

Significantly cooler with diminishing wind Thursday night, with
40s and low 50s common.

Long term Friday through Monday
Overnight model guidance appears to have continued its trend of
a quicker weaker upper trough crossing the region Friday night
into Saturday. This appears to be in response to a stronger
upper low moving into western noam which shoves everything
downstream eastward quicker. The trough axis surface reflection
in the form of a reinforcing cold front are now progged to pass
through our area during the overnight hours. This decreases
further the chance for appreciable rainfall. Behind the front,
an autumnal high of canadian origins (~1030 mb) builds north of
the area bringing cooler and drier air through the weekend.

The tendency of lower heights over the western CONUS would tend
to support a stronger ridge developing over the middle portion
of the country. This ridge then builds towards the eastern conus
during the first part of next week. This results in a very low
chance of rain.

In fact, the last several runs of the GEFS have shown a very
strong negative pna during this time which would suggest strong
to extreme ridging building over the eastern CONUS in the
extended. Operational ECMWF not as extreme but its ensembles
agree with the idea of a strongly negative pna pattern early
next week. By extrapolation, this could lead to significantly
warmer than normal temperatures by the middle of next week.

However, the position of the (~1040 mb) surface high over
southeastern canada could keep a cooler wedge of air near the
surface offsetting the anomalously high heights aloft through at
least Tuesday.

Aviation 08z Tuesday through Saturday
With easterly flow off the ocean developing north of maria, some
low clouds have been trying to advect into the region from the
ocean. So far they have not reached our terminals, but concern
remains that they will before or right around sunrise, so have
maintained ifr for a time this morning at bwi dca iad. Further
west, low clouds should not reach mrb and cho, but patchy fog
may reduce vis. After sunrise, low clouds should gradually lift
and fog should burn off, resulting inVFR conditions for the
balance of the day. Another round of low clouds and fog is
possible tonight, with a return toVFR likely again on Wednesday
afternoon. By Thursday, a strong cold front will bring gusty
northwest winds, preventing any more ifr or even MVFR
conditions, even in the morning. No more than a very isolated
shower is expected through the next few days.

MainlyVFR fri-sat. N winds 10 kts, a few gusts sat.

Marine
Sca over middle bay and adjancent waterways through Wednesday
with maria hanging off the coast. Then, strong cold front will
likely bring SCA to all waters Thursday, and potential for gales
remains with this front. Winds start diminishing late Thursday.

Northerly surge in cool dry advection early Saturday will
likely lead to a period of SCA conditions.

Tides coastal flooding
Water levels will remain elevated through midweek before a cold
frontal passage turns winds northerly and pushes excess water
out the mouth of the bay on Thursday.

Lwx watches warnings advisories
Dc... None.

Md... Coastal flood advisory until noon edt today for mdz017.

Va... None.

Wv... None.

Marine... Small craft advisory from midnight tonight to 6 pm edt
Wednesday for anz533-541-542.

Small craft advisory until 6 pm edt Wednesday for anz534-537-
543.

Synopsis... Rcm
near term... Rcm
short term... Rcm
long term... Dfh
aviation... Rcm dfh
marine... Rcm dfh
tides coastal flooding...



Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
WASD2 - 8594900 - Washington, DC 20 mi51 min Calm G 1.9 70°F 78°F1015.5 hPa
NCDV2 22 mi51 min NE 1.9 G 6 69°F 79°F1014.1 hPa
BSLM2 - Chesapeake Bay, MD 28 mi159 min WNW 1 60°F 1015 hPa60°F
44062 - Gooses Reef, MD 42 mi39 min NE 14 G 16 71°F 1015.5 hPa
TPLM2 - Thomas Point, MD 45 mi69 min ENE 12 G 13 70°F 77°F
SLIM2 - 8577330 - Solomons Island, MD 45 mi51 min NE 7 G 8 69°F 77°F1014.7 hPa
COVM2 - 8577018 - Cove Point LNG Pier, MD 46 mi51 min ENE 12 G 15 69°F 1015.7 hPa
44063 - Annapolis 46 mi39 min E 12 G 14 70°F 1015.6 hPa
APAM2 - 8575512 - Annapolis, MD 46 mi51 min 71°F 1015.2 hPa
PPTM2 - 8578240 - Piney Point, MD 49 mi51 min ENE 6 G 8

Wind History for Washington, DC
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Fort Belvoir, VA8 mi73 minN 010.00 miFair63°F61°F96%1015.5 hPa
Quantico Marine Corps Airfield - Turner Field, VA9 mi73 minESE 510.00 miFair70°F66°F87%1015.7 hPa
Manassas, Manassas Regional Airport/Harry P. Davis Field, VA18 mi73 minN 010.00 miFair64°F62°F93%1016.6 hPa
Washington/Reagan National Airport, DC, VA19 mi77 minNE 610.00 miMostly Cloudy70°F66°F90%1015.5 hPa
Stafford, Stafford Regional Airport, VA20 mi74 minN 07.00 miFair62°F61°F100%1016.6 hPa
Camp Springs / Andrews Air Force Base, MD23 mi71 minENE 410.00 miOvercast66°F65°F97%1015.7 hPa

Wind History from DAA (wind in knots)
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Last 24hrCalmCalmCalmCalmS3SE5NE3NE3E3SE7SE5SE4CalmCalmCalmE3CalmCalmCalmCalmCalmCalmCalmCalm
1 day agoCalmCalmNW4N5NE4CalmN4CalmSE5SE7E4SE5CalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalm
2 days agoCalmCalmNW4NW5N3N5NW7N3NW6W4NW8NW3CalmCalmCalmCalmCalmCalmCalmCalmCalmCalm--Calm

Tide / Current Tables for High Point, Occoquan Bay, Virginia
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High Point
Click for Map
Tue -- 06:31 AM EDT     0.34 feet Low Tide
Tue -- 07:00 AM EDT     Sunrise
Tue -- 12:16 PM EDT     1.60 feet High Tide
Tue -- 12:58 PM EDT     Moonrise
Tue -- 06:09 PM EDT     0.30 feet Low Tide
Tue -- 06:59 PM EDT     Sunset
Tue -- 11:13 PM EDT     Moonset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
1.81.61.310.70.50.40.40.60.91.31.51.61.51.310.60.40.30.30.50.91.31.6

Tide / Current Tables for Marshall Hall, Potomac River, Maryland
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Marshall Hall
Click for Map
Tue -- 12:34 AM EDT     2.61 feet High Tide
Tue -- 06:59 AM EDT     Sunrise
Tue -- 07:07 AM EDT     0.49 feet Low Tide
Tue -- 12:58 PM EDT     Moonrise
Tue -- 01:12 PM EDT     2.30 feet High Tide
Tue -- 06:42 PM EDT     0.43 feet Low Tide
Tue -- 06:58 PM EDT     Sunset
Tue -- 11:12 PM EDT     Moonset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
2.62.62.31.81.30.90.60.50.60.91.51.92.22.32.21.81.20.80.50.40.60.91.52

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 (7,2,3,4)
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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.