Saturday, June24, 2017 L-36.com


Marine Weather and Tides
Potomac Heights, MD

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 5:43AMSunset 8:38PM Saturday June 24, 2017 6:17 AM EDT (10:17 UTC) Moonrise 5:26AMMoonset 8:11PM Illumination 0% Phase: New Moon; Moon at 0 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- 432 Am Edt Sat Jun 24 2017
.gale warning in effect until 8 am edt this morning...
.small craft advisory in effect from 8 am edt this morning through this afternoon...
Rest of the overnight..SW winds 15 kt with gusts to 35 kt. Waves 2 ft. Numerous showers with isolated tstms.
Today..W winds 10 to 15 kt. Gusts up to 35 kt... Diminishing to 25 kt in the late morning and afternoon. Waves 1 ft.
Tonight..NW winds 5 to 10 kt. Waves 1 ft.
Sun..NW winds 5 to 10 kt. Waves 1 ft.
Sun night..NW winds 5 to 10 kt. Waves 1 ft.
Mon..W winds 5 to 10 kt. Waves 1 ft.
Mon night..NW winds 5 kt. Waves less than 1 ft.
Tue..NW winds 5 kt. Waves less than 1 ft.
Wed..SW winds 5 kt. Waves less than 1 ft. Winds and waves higher and visibilities lower in and near tstms.
ANZ500 432 Am Edt Sat Jun 24 2017
Synopsis for the tidal potomac and md portion of the chesapeake bay.. A cold front is crossing the region early this morning. High pressure will build back into the region later today. Additional weak cold fronts will cross the region Sunday through Tuesday. High pressure will cross the region Wednesday. Small craft advisory conditions are possible Sunday through Tuesday.

7 Day Forecast for Marine Location Near Potomac Heights, MD
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location: 38.62, -77.13     debug


Area Discussion for - Baltimore, MD/Washington
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Fxus61 klwx 240750
afdlwx
area forecast discussion
national weather service baltimore md washington dc
350 am edt Sat jun 24 2017

Synopsis
A cold front is crossing the region early this morning. High
pressure will build back into the region later today. Additional
weak cold fronts will cross the region Sunday through Tuesday,
but with little if any precipitation. High pressure will cross
the region Wednesday and then settle over the western atlantic
ocean late in the week.

Near term until 6 pm this evening
Initial boundary associated with the remnant circulation of
cindy is crossing the region with a squall line at this time.

Not much depth to the line but a rumble of thunder can't be
ruled out, along with a brief wind gust to around 40 mph and
brief blinding downpour. After the line and front clears the
area, northwest flow will start bringing drier air into the
region. All showers should clear the area before midday, with
midday and afternoon turning out mostly sunny. Temperatures will
still be quite warm with good mixing behind the front, so still
expecting highs well into the 80s, with 90 possible in the warm
spots. However, dew ponts will generally be sliding downward, so
it won't feel as oppressive.

Short term 6 pm this evening through Monday night
The remainder of the short term will feature an upper trough
settling over the great lakes, and surface high pressure over
the central us. Northwest surface flow and passing disturbances
aloft will bring weak reinforcing cold fronts southwest across
the area. With much drier air in place, little if any precip is
expected with these fronts, though an isolated shower or t-storm
can't be completely ruled out, especially Monday and Monday
night as a little more forcing is present aloft. Otherwise,
temperatures will be sliding downward each day, with low-mid 80s
Sunday and upper 70s to low 80s Monday. Lows will decline in a
similar fashion, with low-mid 60s common tonight, upper 50s to
low 60s more likely Sunday night, and mid-upper 50s more common
Monday night.

Long term Tuesday through Friday
Cool (for late june) weather to start the long term as an upper
trough starts sliding east across the region and high pressure
to our west keeps a cool northwest flow in place. The passing
trough may result in enough instability to result in a stray
shower or t-storm Tuesday, but most spots stay dry. The trough
starts moving east away from us Wednesday, with ridging building
in from the southwest late in the week as the surface high
pushes east and sets up shop off the coast (i.E. A bermuda
high). This will result in temperatures starting to warm back
above normal by the end of the week, and an increasing risk of
diurnal terrain showers and storms in the mountains by Friday.

Aviation 08z Saturday through Wednesday
Variable conditions this morning as cold front and squall line
moves through. Occasional ifr with heavy rain and gusty winds to
35 knots possible as cold front passes. After it is through,
generally expectVFR through remainder of forecast period, with
winds diminishing, especially tonight. An isolated thunderstorm
could occur Monday or Tuesday with a weak reinforcing cold front
and following upper trough, but odds are low.

Marine
Gale warning remains in effect for all waters through 8am for
gusty winds associated with approaching squall line. However,
we may be able to downgrade it back to SCA early as the line is
progressing east rapidly and do not expect gales to continue for
a significant period behind the line. High pressure building in
behind the cold front which will accompany the squalls should
conitnue to cause sporadic SCA gusts today, but odds of
continued SCA winds beyond this afternoon, while not negligible,
look low, and therefore have not extended headlines any further.

Will need to watch for potential mixing and resulting SCA gusts
Sunday and Monday with multiple weak reinforcing cold fronts
moving through, however. Otherwise, mainly dry through the rest
of the forecast period, with just an isolated thunderstorm
possible Monday or Tuesday with a weak front and following
trough.

Hydrology
While pw's have been high, forcing has been mostly northwest of
our region, so heavy rains have mostly stayed north and west of
the cwa. Last bands of heavier rain moving through now should
not pose any significant flooding issues, especially given
overall below normal rainfall for june thus far. After early
this morning, rainfall through the rest of the forecast period
looks meager.

Tides coastal flooding
Coastal flood advisories up for several portions of our upper
bay shore along with the dc waterfront right now thanks to
persistent southerly flow and above normal astronomical tides.

This should be a one-cycle event, however, since northwest winds
are already enveloping the region behind the approaching cold
front. Water levels should stay below minor flood thresholds for
the foreseable future after this morning's high tide.

Lwx watches warnings advisories
Dc... Coastal flood advisory from 7 am to 10 am edt this morning for
dcz001.

Md... Coastal flood advisory until 8 am edt this morning for mdz018.

Coastal flood advisory until 10 am edt this morning for mdz014.

Coastal flood advisory until 11 am edt this morning for mdz011.

Coastal flood advisory from 8 am this morning to 1 pm edt this
afternoon for mdz508.

Va... None.

Wv... None.

Marine... Small craft advisory from 8 am this morning to 6 pm edt this
evening for anz530>543.

Gale warning until 8 am edt this morning for anz530>543.

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


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
44061 - Upper Potomac, MD 13 mi60 min WNW 9.7 G 16 71°F 82°F1003 hPa
WASD2 - 8594900 - Washington, DC 18 mi48 min NW 11 G 17 74°F 82°F1004.1 hPa
NCDV2 21 mi48 min WSW 15 G 21 80°F 80°F1003 hPa
BSLM2 - Chesapeake Bay, MD 25 mi108 min SSE 7 76°F 1001 hPa72°F
44062 - Gooses Reef, MD 38 mi38 min W 19 G 25 81°F 1002.6 hPa
SLIM2 - 8577330 - Solomons Island, MD 41 mi48 min SW 19 G 25 82°F 77°F
TPLM2 - Thomas Point, MD 42 mi78 min S 22 G 24 80°F 78°F
COVM2 - 8577018 - Cove Point LNG Pier, MD 42 mi48 min SW 19 G 25 82°F 1003.1 hPa
44063 - Annapolis 43 mi38 min WNW 21 G 29 77°F 1003.2 hPa
APAM2 - 8575512 - Annapolis, MD 43 mi48 min 76°F 1002.5 hPa
PPTM2 - 8578240 - Piney Point, MD 46 mi48 min WSW 13 G 17
CPVM2 47 mi48 min 79°F 76°F

Wind History for Washington, DC
(wind in knots)    EDIT      (on/off)   Help
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Fort Belvoir, VA8 mi20 minWNW 1210.00 miPartly Cloudy72°F67°F86%1005.7 hPa
Quantico Marine Corps Airfield - Turner Field, VA12 mi22 minNW 1110.00 miLight Rain74°F70°F88%1006.1 hPa
Washington/Reagan National Airport, DC, VA17 mi26 minVar 610.00 miMostly Cloudy74°F70°F88%1005.1 hPa
Camp Springs / Andrews Air Force Base, MD20 mi80 minSSW 16 G 268.00 miRain77°F73°F87%1002.4 hPa
Manassas, Manassas Regional Airport/Harry P. Davis Field, VA22 mi22 minWNW 810.00 miA Few Clouds71°F68°F90%1007 hPa
Stafford, Stafford Regional Airport, VA23 mi23 minWNW 610.00 miFair72°F69°F92%1007.4 hPa

Wind History from DAA (wind in knots)
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Last 24hrSE3S5S7S5S6
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1 day agoCalmS3CalmS3CalmS6SW4W5SW5S4SW4S4S3CalmCalmCalmSE3CalmS4S3CalmCalmSW3SW3
2 days agoCalmS6SW3S6S8S6SW4NW6W7S5S5S6S4CalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalm

Tide / Current Tables for Glymont, Potomac River, Maryland
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Glymont
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Sat -- 02:00 AM EDT     0.06 feet Low Tide
Sat -- 05:45 AM EDT     Sunrise
Sat -- 06:25 AM EDT     Moonrise
Sat -- 07:47 AM EDT     2.42 feet High Tide
Sat -- 02:57 PM EDT     -0.07 feet Low Tide
Sat -- 08:27 PM EDT     2.04 feet High Tide
Sat -- 08:36 PM EDT     Sunset
Sat -- 09:10 PM EDT     Moonset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
0.40.20.10.20.71.422.32.42.21.71.20.80.40.1-0.10.10.71.31.8221.71.2

Tide / Current Tables for Mount Vernon, Virginia
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Mount Vernon
Click for Map
Sat -- 02:33 AM EDT     0.06 feet Low Tide
Sat -- 05:44 AM EDT     Sunrise
Sat -- 06:25 AM EDT     Moonrise
Sat -- 08:19 AM EDT     2.97 feet High Tide
Sat -- 03:29 PM EDT     -0.12 feet Low Tide
Sat -- 08:36 PM EDT     Sunset
Sat -- 08:59 PM EDT     2.52 feet High Tide
Sat -- 09:10 PM EDT     Moonset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
0.70.40.10.10.51.22.12.72.92.92.41.81.20.70.3-0.1-0.10.41.21.92.42.52.31.8

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 (6,6,7,8)
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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.