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Marine Weather and Tides
Version 3.4 |
1/26/2021 -- The West Coast Satellite images havd been updated. They now use GEOS-17. 1/1/2021 -- The 7 day forecast are now working well. Thank you NOAA for your support. |
Sunrise 6:46AM | Sunset 5:58PM | Wednesday February 24, 2021 12:37 PM EST (17:37 UTC) | Moonrise 3:01PM | Moonset 5:20AM | Illumination 95% | ![]() |
ANZ535 Tidal Potomac From Key Bridge To Indian Head- 939 Am Est Wed Feb 24 2021
.small craft advisory in effect until 6 pm est this evening...
Rest of today..S winds 10 kt with gusts to 20 kt. Waves 1 ft.
Tonight..NW winds 5 to 10 kt. Gusts up to 25 kt. Waves 1 ft.
Thu..NW winds 5 to 10 kt. Gusts up to 25 kt in the morning. Waves 1 ft.
Thu night..NW winds around 5 kt. Waves 1 ft.
Fri..SE winds around 5 kt. Waves 1 ft.
Fri night..SE winds 5 kt. Waves less than 1 ft. Rain likely.
Sat..SW winds 5 kt. Waves less than 1 ft. Rain likely through the day, then a chance of rain through the night.
Sun..S winds 5 kt. Waves less than 1 ft. Rain likely.
.small craft advisory in effect until 6 pm est this evening...
Rest of today..S winds 10 kt with gusts to 20 kt. Waves 1 ft.
Tonight..NW winds 5 to 10 kt. Gusts up to 25 kt. Waves 1 ft.
Thu..NW winds 5 to 10 kt. Gusts up to 25 kt in the morning. Waves 1 ft.
Thu night..NW winds around 5 kt. Waves 1 ft.
Fri..SE winds around 5 kt. Waves 1 ft.
Fri night..SE winds 5 kt. Waves less than 1 ft. Rain likely.
Sat..SW winds 5 kt. Waves less than 1 ft. Rain likely through the day, then a chance of rain through the night.
Sun..S winds 5 kt. Waves less than 1 ft. Rain likely.
ANZ500 939 Am Est Wed Feb 24 2021
Synopsis for the tidal potomac and md portion of the chesapeake bay.. High pressure will move offshore today with a cold front passing through tonight. High pressure will return for Thursday into Friday, but low pressure may impact the waters later Friday into the weekend. Small craft advisories may be needed for portions of the waters tongiht into Thursday.
Synopsis for the tidal potomac and md portion of the chesapeake bay.. High pressure will move offshore today with a cold front passing through tonight. High pressure will return for Thursday into Friday, but low pressure may impact the waters later Friday into the weekend. Small craft advisories may be needed for portions of the waters tongiht into Thursday.
7 Day Forecast for Marine Location Near Oakton, VA
Hourly EDIT Help
location: 38.88, -77.3 debug
Area Discussion for - Baltimore, MD/Washington
  (on/off)  Help NOTE: mouseover dotted underlined text for definitionFXUS61 KLWX 241448 AFDLWX
Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 948 AM EST Wed Feb 24 2021
SYNOPSIS. High pressure will gradually build in from the southwest today. A weak cold front will cross the area later this afternoon, with high pressure building back in Thursday. Another low pressure system may impact the region toward the end of the week.
NEAR TERM /THROUGH TONIGHT/.
A noticeable low level stable layer was present on the 12Z LWX sounding. Broken clouds were in place this morning but these clouds are breaking up and mostly clear skies are expected over the next few hours. As skies clear, increased mixing will lead to the eroding of the low level stable layer which will allow temperatures to rapidly jump up as warm air aloft is mixed to the surface.
..Previous Discussion
Calm to light and variable winds with temperatures ranging from the upper 20s to middle 30s across the region with mainly clear skies due to high pressure early this morning.
High pressure will build over the southeastern states today. Warmer air will be drawn into the area by gusty southwest winds, with most locations in the 50s to mid 60s. Low pressure will be crossing the Great Lakes, dragging a weak cold front toward the area by this evening. Clouds will increase, and rain showers will approach from the northwest. Most of the showers should fizzle out crossing the Appalachians due to limited moisture and forcing. Besides the Alleghenies, northern Maryland and eastern West Virginia will have the best chance for a brief shower or sprinkle during the early evening. Precipitation may end as some snow showers west of the Allegheny Front, but accumulations should be minimal.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/. Thursday will feature clearing skies and northwest winds ushering in cooler air as high pressure builds over the Mississippi Valley. However, temperatures will remain near or slightly above seasonable averages. Clouds will increase Thursday night ahead of a shortwave trough, but dry weather is expected.
A more active and unsettled pattern returns Friday through the weekend. An area of surface high pressure will reside to our north during the day Friday before gradually moving offshore Friday night. Multiple areas of low pressure will advance towards the region Friday afternoon and evening. This leads to the possibility of another CAD set up with a wintry mix at the onset of precip over the western highlands of our CWA.
LONG TERM /SATURDAY THROUGH TUESDAY/. On the synoptic-scale, the features controlling the weather will be as follows. A subtropical ridge remains fixed over the central to eastern Gulf of Mexico into early next week while a split in the jets is noted to its north and west. Mid-level heights remain on the higher end over the weekend, generally around 570-dm.
With a strong surface ridge moving off the coast into the Atlantic, return flow will commence ushering in southeasterly winds on Saturday morning before turning more westerly by the evening as a cold front sweeps through. Unsettled conditions are likely before the frontal passage with snow mixing in with rain during the morning hours. This would mainly impact the higher terrain. Continued warm advection will eventually shift precipitation to all rain later in the morning. Meager amounts are forecast, generally maximizing in the tenth to quarter inch range.
As the flow aloft turns more west-southwesterly in nature, the mentioned cold front gradually stalls south of the region on Sunday. Ample moisture advection occurring within the confluent flow across the Ozarks into the Tennessee/Ohio Valleys will bring precipitation back to the area for Sunday. The culprit is a series of perturbations in the flow, each providing an impetus for periods of rainfall. While the air mass is quite mild in nature, cannot rule out some snowflakes across the higher peaks. Sunday will likely be the wetter of the two weekend days.
The northern stream really begins to amplify on Monday with height falls crossing the Mid-Atlantic region by the evening. The 00Z GFS solutions remains the most aggressive with a deep surface low tracking through New England. This would bring a much more potent frontal passage on Monday evening. It does appear the stalled baroclinic zone over the weekend shifts farther south which moves the moisture gradient back toward southern Virginia. Thus, aside from some morning rainfall, the remainder of the day appears to be dry in the wake of the cold front. After a mild weekend and early start to the week, temperatures are expected to drop off by 5 to 10 degrees bringing conditions closer to climatology by Tuesday. Ensemble solutions differ beyond this period, but the upper pattern becomes quasi-zonal. This will maintain chances for precipitation with near average temperatures.
AVIATION /15Z WEDNESDAY THROUGH SUNDAY/.
VFR conditions are expected today. South/southwest wind gusts to 25 kts are possible this afternoon. A weak front this evening will shift winds to the northwest, but other than a brief sprinkle, dry conditions are expected. VFR continues Thursday with high pressure.
With a chance for rainfall during much of the weekend, some periods of sub-VFR conditions are likely, especially on Sunday. Winds are not particularly strong, but multiple directional shifts are possible.
MARINE. Wind gusts of 20 to 25 kt are expected to return out of the south ahead of a cold front this afternoon, and a few gusts to near gale forecast can't completely be ruled out over the upper tidal Potomac River and upper portion of the Bay.
A weak front this evening will shift winds to the northwest. A SCA may be needed for portions of the waters through Thursday morning before high pressure builds in and winds relax.
SCA conditions are not expected for the weekend but increasing northwesterly wind behind a cold front could bring enhanced marine winds on Monday.
LWX WATCHES/WARNINGS/ADVISORIES. DC . None. MD . None. VA . None. WV . None. MARINE . Small Craft Advisory until 11 AM EST Thursday for ANZ531>534- 537>543. Small Craft Advisory until 6 PM EST this evening for ANZ530- 535-536.
SYNOPSIS . KLW NEAR TERM . KLW/JMG SHORT TERM . KLW LONG TERM . BRO AVIATION . BRO/KLW/JMG MARINE . BRO/KLW
Weather Reporting Stations
EDIT (on/off)  Help NOTE: Click on distance to see the station location on a mapStations | Dist | Age | Wind | Air Temp | Water Temp | Waves | Pressure | DewPt |
WASD2 - 8594900 - Washington, DC | 15 mi | 50 min | S 9.9 G 12 | 53°F | 38°F | 1018.7 hPa | ||
BSLM2 - Chesapeake Bay, MD | 32 mi | 68 min | SW 11 | 51°F | 1018 hPa | 37°F | ||
NCDV2 | 41 mi | 56 min | E 4.1 G 6 | 46°F | 38°F | 1019 hPa | ||
APAM2 - 8575512 - Annapolis, MD | 44 mi | 50 min | 50°F | 1018.1 hPa | ||||
TPLM2 - Thomas Point, MD | 46 mi | 38 min | SSE 21 G 23 | 43°F | 37°F | 1019.2 hPa (-1.3) | 32°F | |
BLTM2 - 8574680 - Baltimore, MD | 47 mi | 50 min | S 7 G 12 | 50°F | 38°F | 1017.4 hPa | ||
FSKM2 - 8574728 - Francis Scott Key Bridge, MD | 47 mi | 50 min | SSE 16 G 16 | 49°F | 1017.6 hPa | |||
FSNM2 | 47 mi | 50 min | SSE 12 G 15 | 51°F | 1017.3 hPa | |||
CPVM2 | 49 mi | 50 min | 43°F | 34°F |
Wind History for Washington, DC
(wind in knots) EDIT (on/off)  Help12 PM | 1 PM | 2 PM | 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 | |
Last 24hr | SW G17 | W G14 | W G18 | W G25 | W G27 | NW G19 | NW G17 | NW G9 | W G6 | -- | S | N | NW | N | S | -- | -- | -- | SE | -- | -- | -- | S | S G11 |
1 day ago | SW | S | S G15 | SW G9 | SW | SW G6 | W | -- | -- | SE | SE | SE | -- | S | SE | S | SW | -- | SW | S | S G8 | S | S G11 | S G13 |
2 days ago | NE G5 | SW | SW | S | S | S | S | SE | SE | S | SE | S | S G11 | S | S | S G9 | S | S | S | S G13 | S | S | S G8 | S G7 |
Airport Reports
EDIT (on/off)  Help Click EDIT to display multiple airports. Follow links for more data.Airport | Dist | Age | Wind kt | Visibility | Sky/Weather | Temp | DewPt | Humidity | Pressure |
Washington/Dulles International Airport, DC, VA | 10 mi | 46 min | SSW 11 | 10.00 mi | A Few Clouds | 57°F | 30°F | 36% | 1017.8 hPa |
Fort Belvoir, VA | 12 mi | 42 min | S 8 | 10.00 mi | Fair | 57°F | 29°F | 34% | 1018.6 hPa |
Washington/Reagan National Airport, DC, VA | 14 mi | 46 min | S 13 | 10.00 mi | A Few Clouds | 55°F | 31°F | 40% | 1018.6 hPa |
Manassas, Manassas Regional Airport/Harry P. Davis Field, VA | 16 mi | 42 min | SSW 10 | 10.00 mi | Fair | 59°F | 33°F | 38% | 1018.8 hPa |
Leesburg / Godfrey, VA | 20 mi | 43 min | S 13 G 21 | 10.00 mi | Fair | 59°F | 32°F | 36% | 1017.6 hPa |
Gaithersburg - Montgomery County Airport, MD | 21 mi | 42 min | S 13 G 17 | 10.00 mi | Fair | 58°F | 27°F | 31% | 1019.3 hPa |
College Park Airport, MD | 21 mi | 43 min | S 4 G 14 | 10.00 mi | Fair | 57°F | 22°F | 26% | 1017.9 hPa |
Camp Springs / Andrews Air Force Base, MD | 23 mi | 42 min | SSW 14 | 10.00 mi | Fair | 57°F | 30°F | 36% | 1018.3 hPa |
Link to 5 minute data for KIAD
Wind History from IAD (wind in knots)
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 | -12 PM | |
Last 24hr | ||||||||||||||||||||||||
1 day ago | ||||||||||||||||||||||||
2 days ago |
Tide / Current Tables for Chain Bridge, D.C.
EDIT Weekend mode (on/off) (on/off)  Help One Week of DataChain Bridge
Click for Map
Wed -- 12:35 AM EST 0.22 feet Low Tide
Wed -- 05:19 AM EST Moonset
Wed -- 06:16 AM EST 2.52 feet High Tide
Wed -- 06:47 AM EST Sunrise
Wed -- 12:29 PM EST 0.16 feet Low Tide
Wed -- 03:00 PM EST Moonrise
Wed -- 05:56 PM EST Sunset
Wed -- 06:26 PM EST 2.84 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Click for Map
Wed -- 12:35 AM EST 0.22 feet Low Tide
Wed -- 05:19 AM EST Moonset
Wed -- 06:16 AM EST 2.52 feet High Tide
Wed -- 06:47 AM EST Sunrise
Wed -- 12:29 PM EST 0.16 feet Low Tide
Wed -- 03:00 PM EST Moonrise
Wed -- 05:56 PM EST Sunset
Wed -- 06:26 PM EST 2.84 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
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 |
0.3 | 0.3 | 0.6 | 1.3 | 1.9 | 2.3 | 2.5 | 2.4 | 2 | 1.4 | 0.8 | 0.4 | 0.2 | 0.2 | 0.5 | 1.2 | 2 | 2.6 | 2.8 | 2.8 | 2.4 | 1.9 | 1.3 | 0.8 |
Tide / Current Tables for Chain Bridge, one mile below, D.C.
EDIT (on/off)  Help One Week of DataChain Bridge
Click for Map
Wed -- 12:29 AM EST 0.22 feet Low Tide
Wed -- 05:19 AM EST Moonset
Wed -- 06:11 AM EST 2.52 feet High Tide
Wed -- 06:47 AM EST Sunrise
Wed -- 12:24 PM EST 0.16 feet Low Tide
Wed -- 03:00 PM EST Moonrise
Wed -- 05:56 PM EST Sunset
Wed -- 06:21 PM EST 2.84 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Click for Map
Wed -- 12:29 AM EST 0.22 feet Low Tide
Wed -- 05:19 AM EST Moonset
Wed -- 06:11 AM EST 2.52 feet High Tide
Wed -- 06:47 AM EST Sunrise
Wed -- 12:24 PM EST 0.16 feet Low Tide
Wed -- 03:00 PM EST Moonrise
Wed -- 05:56 PM EST Sunset
Wed -- 06:21 PM EST 2.84 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
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 |
0.3 | 0.3 | 0.6 | 1.3 | 1.9 | 2.3 | 2.5 | 2.4 | 2 | 1.4 | 0.8 | 0.4 | 0.2 | 0.2 | 0.6 | 1.3 | 2.1 | 2.6 | 2.8 | 2.8 | 2.4 | 1.8 | 1.3 | 0.8 |
Weather Map
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GEOS Local Image of EDIT
NOTE: This section has been updated as of 1/26/2021. If the image you are expecting is not showing, please let me know. You may use the EDIT function to update your location.
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