Monday, August10, 2020
Privacy Policy
L-36.com


Marine Weather and Tides
George Mason, VA

Version 3.4
NOTICE
12/16/2019 NOAA is having trouble with requests that include wind gusts. I am posting graphs without wind gusts until it gets fixed.
10/9/2019 Updated the Marine Zones.
9/4/2019 Fixed the weather maps due to NOAA moving them.
7/25/2019 New feature in the Airports section gives a link to 5 minute updates for data reports.

Sunrise 6:17AMSunset 8:11PM Monday August 10, 2020 3:21 PM EDT (19:21 UTC) Moonrise 10:56PMMoonset 11:50AM Illumination 57% Phase: Waning Gibbous; Moon at 21 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
    EDIT      (on/off)   Help
ANZ535 Tidal Potomac From Key Bridge To Indian Head- 257 Pm Edt Mon Aug 10 2020
This afternoon..S winds 5 kt. Waves less than 1 ft. Isolated showers and tstms.
Tonight..S winds 5 kt. Waves less than 1 ft.
Tue..S winds 5 kt. Waves less than 1 ft. A chance of showers and tstms.
Tue night..S winds 5 kt. Waves less than 1 ft.
Wed..SE winds around 5 kt. Waves 1 ft. A chance of showers and tstms.
Wed night..SE winds around 5 kt. Waves 1 ft or less. A chance of showers and tstms.
Thu..SE winds around 5 kt. Waves 1 ft or less. Showers likely with a chance of tstms, then a chance of showers after midnight.
Fri..SE winds around 5 kt. Waves 1 ft. Showers likely with a chance of tstms, then a chance of showers after midnight. Winds and waves higher and visibilities lower in and near tstms.
ANZ500 257 Pm Edt Mon Aug 10 2020
Synopsis for the tidal potomac and md portion of the chesapeake bay.. High pressure will build across the waters through Tuesday. A cold front will approach from the northwest during the middle of the week, stalling in the area as the week progresses.


7 Day Forecast for Marine Location Near George Mason, VA
   Hourly   EDIT   Help
location: 38.84, -77.3     debug


Area Discussion for - Baltimore, MD/Washington
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
FXUS61 KLWX 101847 AFDLWX

Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 247 PM EDT Mon Aug 10 2020

SYNOPSIS. High pressure will settle to the south of our area through tonight. A cold front will approach late Tuesday into Tuesday night and remain stalled near our area through the end of the week.

NEAR TERM /THROUGH TONIGHT/. Temperatures have climbed into the lower 90s during these mid- afternoon hours. Given the fact that rich moisture near the ground of dewpoint temperatures in the lower to middle 70s are present, showers and a few thunderstorms are developing across parts of the Blue Ridge Mountains and eastern portions of Virginia. This activity is slow-moving and actually showing signs of producing their own surface boundaries in the form of outflow boundaries or gustfronts from their downdrafts. The importance of this is that although there are only a couple of showers and thunderstorms currently present, additional showers and thunderstorms will develop around these because of the added lift from the outflow boundaries or gustfronts. The main threat will be heavy rainfall, but also a concern may be the downburst of gusty winds from the stronger thunderstorms late this afternoon. There will be more showers and storms over the southeastern half of our CWA than our northwestern half; however, any thunderstorm that does develop over western Maryland and eastern West Virginia will have the same capabilities of producing heavy rain and gusty winds. Because of the heat and humidity, our heat indices will reach the upper 90s to low 100s.

Dry conditions expected tonight after early evening showers and thunderstorms dissipate and weak high pressure builds overhead. Fog could develop again late tonight and reduce visibility to around one-half mile to one mile near CHO and any terminal encountering an afternoon shower or thunderstorm.

SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/. A southerly flow will continue Tuesday ahead of an approaching cold front. Warm and moist air advection will again allow for heat index values to reach the upper 90s, maybe a few areas in the lower 100s. Upper level energy aloft and diurnal heating will allow for another day of afternoon and evening showers and thunderstorms as the front continues to approach our area. Drier conditions on Tuesday night.

On Wednesday, the cold front is expected to stall and linger into Wednesday night. Upper level energy will move in from the west, bringing increased chances for showers and thunderstorms. Heat index values again will reach the upper 90s and maybe the low 100s as we remain under southerly flow.

LONG TERM /WEDNESDAY THROUGH MONDAY/. An upper-level trough (and perhaps even a closed upper-level low) will develop over the Ohio Valley into the Tennessee Valley Thursday through Saturday while high pressure builds over New England. A backdoor boundary will move into the region from the Thursday and it will stall out nearby for Friday and Saturday. Tropical moisture from the Gulf of Mexico and Atlantic Ocean will get drawn into the area during this time. The 00z NAEFS forecast progs PWAT standardized anomalies to be close to +2 for this time of year.

The combination of the boundary, easterly component from the Atlantic, lower heights, and weak steering flow suggest that showers and thunderstorms will become more widespread, and also that some will contain heavy rainfall that increases the threat for flash flooding. Confidence in regards to timing and location remain low at this time. Also, it is not out of the question that a couple storms become severe, but a weak flow aloft suggests that threat would be more localized.

A stronger cold front will approach from the west Sunday before passing through Monday. This will bring the chance for more showers and thunderstorms, and with increased shear that poses a threat for severe storms. Details remain highly uncertain at this time.

AVIATION /19Z MONDAY THROUGH SATURDAY/. VFR conditions expected over the terminals late this afternoon into early this evening. Any reduction to MVFR will be from a heavy shower or thunderstorm moving overhead. Any storms will be isolated to widely scattered.

By Tuesday, showers and thunderstorms will increase in coverage during the afternoon and evening. MVFR or IFR conditions not out of the question with this convection.

Shower and thunderstorm chances will be even higher Wednesday into Wednesday evening with a stalled front.

Shower and thunderstorm coverage may become more widespread for Thursday through Saturday as a backdoor cool front moves into the area Thursday and stalls out nearby for Friday and Saturday. An easterly component to the low-level flow may also increase the coverage of low clouds and subVFR conditions, especially during the overnight and morning hours each day.

MARINE. Winds will remain below Small Craft Advisory criteria through tonight. Winds may gust into the teens on Tuesday and Wednesday afternoons, but looks like they will remain below SCA criteria. Some shower and thunderstorm activity developing along a river breeze boundary or sea breeze boundary could bring gusty winds this afternoon and evening. Chances for convection increase on Tuesday and Wednesday ahead of a front.

A backdoor boundary will move into the area Thursday and it will stall out nearby to the south and west for Friday and Saturday. An easterly component to the wind is expected, but for the most part the gradient will be light so winds should remain below SCA criteria most of the time. Perhaps Saturday the gradient will be a bit stronger, but confidence is low.

Plenty of moisture will increase the chances for showers and thunderstorms Thursday through Saturday as well.

TIDES/COASTAL FLOODING. Elevated water levels will persist over the next couple days. The flow will be relatively light, so the most likely scenario is that sensitive areas will be around action stage.

LWX WATCHES/WARNINGS/ADVISORIES. DC . None. MD . None. VA . None. WV . None. MARINE . None.

SYNOPSIS . KLW NEAR TERM . KLW SHORT TERM . KLW LONG TERM . BJL AVIATION . BJL/KLW MARINE . BJL/KLW


Weather Reporting Stations
   EDIT       (on/off)   Help   NOTE: Click on distance to see the station location on a map
Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
WASD2 - 8594900 - Washington, DC 15 mi52 min SSW 4.1 G 6 91°F 82°F1016.5 hPa
BSLM2 - Chesapeake Bay, MD 32 mi112 min SSE 4.1 1017 hPa
NCDV2 39 mi52 min ESE 9.9 G 12 86°F 90°F1016.1 hPa
APAM2 - 8575512 - Annapolis, MD 45 mi52 min ESE 6 G 8 90°F 85°F1016.2 hPa
TPLM2 - Thomas Point, MD 46 mi82 min SE 7 G 8 83°F 84°F1018 hPa (-1.2)78°F
BLTM2 - 8574680 - Baltimore, MD 48 mi52 min S 11 G 13 87°F 83°F1016 hPa
FSKM2 - 8574728 - Francis Scott Key Bridge, MD 49 mi52 min SE 12 G 14 85°F 1016.4 hPa
FSNM2 49 mi70 min SE 11 G 13 86°F 1016.6 hPa

Wind History for Washington, DC
(wind in knots)    EDIT      (on/off)   Help
3
PM
4
PM
5
PM
6
PM
7
PM
8
PM
9
PM
10
PM
11
PM
12
AM
1
AM
2
AM
3
AM
4
AM
5
AM
6
AM
7
AM
8
AM
9
AM
10
AM
11
AM
12
PM
1
PM
2
PM
Last
24hr
--
S4
S4
S6
S6
S5
S2
SE2
S4
S3
S5
S4
S4
SW4
SW3
SW2
S2
S3
--
SE2
S2
S4
S5
SW4
1 day
ago
W3
NE4
G9
W2
G5
W2
S3
SE4
SE4
SE2
S3
SE2
SE2
SW2
SE5
SW1
G4
SW1
--
SW1
S3
S4
S5
S7
S5
G8
S7
G10
S10
2 days
ago
S6
S8
S8
S5
G9
S4
G7
SW3
G9
NE5
G12
N3
G8
NE1
SE3
E1
--
E1
NE1
G4
NE2
NE1
G4
NE3
NE4
--
NW1
G4
S1
G4
--
SE1
S2

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports. Follow links for more data.
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Fort Belvoir, VA10 mi26 minSE 610.00 miFair90°F72°F56%1016.5 hPa
Washington/Dulles International Airport, DC, VA11 mi30 minVar 410.00 miMostly Cloudy91°F69°F49%1016.1 hPa
Manassas, Manassas Regional Airport/Harry P. Davis Field, VA14 mi26 minVar 610.00 miA Few Clouds91°F72°F54%1016.8 hPa
Washington/Reagan National Airport, DC, VA14 mi30 minS 710.00 miPartly Cloudy91°F72°F54%1016.2 hPa
Leesburg / Godfrey, VA22 mi27 minW 310.00 miFair91°F69°F49%1017.3 hPa
College Park Airport, MD22 mi47 minNE 310.00 miMostly Cloudy88°F67°F51%1016.3 hPa
Camp Springs / Andrews Air Force Base, MD23 mi26 minSSE 610.00 miFair90°F70°F53%1016.6 hPa
Quantico Marine Corps Airfield - Turner Field, VA23 mi26 minS 59.00 miFair89°F73°F61%1016.3 hPa
Gaithersburg - Montgomery County Airport, MD24 mi26 minN 010.00 miMostly Cloudy85°F75°F75%1018.2 hPa

Link to 5 minute data for KDAA

Wind History from DAA (wind in knots)
4
PM
5
PM
6
PM
7
PM
8
PM
9
PM
10
PM
11
PM
12
AM
1
AM
2
AM
3
AM
4
AM
5
AM
6
AM
7
AM
8
AM
9
AM
10
AM
11
AM
12
PM
1
PM
2
PM
3
PM
Last 24hrCalmSE5S5SE3CalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmSE3SE5S4SE6
1 day agoCalmNE3CalmCalmS3CalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmSW3S4SE7S6S4S3S5
2 days agoSW6SE6S5S3CalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmN3CalmCalmCalmCalmS3CalmCalmE3

Tide / Current Tables for Chain Bridge, one mile below, D.C.
   EDIT   Weekend mode (on/off)   (on/off)   Help   One Week of Data
Chain Bridge
Click for Map
Mon -- 01:43 AM EDT     3.11 feet High Tide
Mon -- 06:17 AM EDT     Sunrise
Mon -- 08:24 AM EDT     0.69 feet Low Tide
Mon -- 12:49 PM EDT     Moonset
Mon -- 02:06 PM EDT     2.82 feet High Tide
Mon -- 08:08 PM EDT     Sunset
Mon -- 08:10 PM EDT     0.46 feet Low Tide
Mon -- 11:54 PM EDT     Moonrise
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

12
am
1
am
2
am
3
am
4
am
5
am
6
am
7
am
8
am
9
am
10
am
11
am
12
pm
1
pm
2
pm
3
pm
4
pm
5
pm
6
pm
7
pm
8
pm
9
pm
10
pm
11
pm
2.733.12.92.41.81.30.90.70.71.11.72.32.72.82.72.31.71.10.60.50.50.91.6

Tide / Current Tables for Chain Bridge, D.C.
   EDIT      (on/off)   Help   One Week of Data
Chain Bridge
Click for Map
Mon -- 01:48 AM EDT     3.11 feet High Tide
Mon -- 06:17 AM EDT     Sunrise
Mon -- 08:29 AM EDT     0.69 feet Low Tide
Mon -- 12:49 PM EDT     Moonset
Mon -- 02:11 PM EDT     2.82 feet High Tide
Mon -- 08:08 PM EDT     Sunset
Mon -- 08:15 PM EDT     0.46 feet Low Tide
Mon -- 11:54 PM EDT     Moonrise
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

12
am
1
am
2
am
3
am
4
am
5
am
6
am
7
am
8
am
9
am
10
am
11
am
12
pm
1
pm
2
pm
3
pm
4
pm
5
pm
6
pm
7
pm
8
pm
9
pm
10
pm
11
pm
2.733.12.92.41.81.30.90.70.711.62.32.72.82.72.31.71.10.70.50.50.81.5

Weather Map
       (on/off)   Help Weather Map
wmap_A
GEOS 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.
Link to Loop

Other links: Northern Pacific     Contential US     Full GOES-East
Wind Forecast for Baltimore, MD/Washington (15,3,4,5)
      (on/off)   Help

Ground Weather Radar Station Sterling, VA
   (on/off)   Help
weather_mapweather_map weather_map

Ad by Google

Cookie Policy:
This website uses cookies to save your settings. No personal information is saved. I do not collect statistics on your visit. You can disable cookies in your browser if you like but it is not recommended for this site. I do not sell cookies. Go to a bakery for that. In fact I do not sell anything. To disable cookies from L-36.com, please refer to the Help button in your browser.
Privacy Policy:
I do not sell or share any user data or anything else for that matter. The only personal information I save is in the site log which has a line for each page view which includes the IP address your browser sends in the header as well as which page you requested. I use this to block hackers and other bad actors. I do not use this raw data to create profiles on users. I periodically delete the log files. If you are subject to CCPA, Google ads on this site will not be based on your past behavior so you will likely not see an ad for a lawn mower just because you looked for one at a big box website. I do not believe this site is subject to CCPA but I am doing what I can to follow the guidelines anyway.
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 numerous 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.