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Marine Weather and Tides National Harbor, MD Version 3.4

NOTICE 7/25/2019 New feature in the Airports section gives a link to 5 minute updates for data reports. 6/2/2019. Many thanks to a user for reporting an error on one of the Edit pages. The switch to PHP 7.2 caused many pages that previously worked to quit working. I fixed many but I still depend on users to report ones I missed. Please report errors HERE or send an email to me at L-36.com. Allen

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Sunrise 6:29AM

Sunset 7:51PM

Sunday August 25, 2019 11:23 AM EDT (15:23 UTC)

Moonrise 12:06AM

Moonset 3:05PM

Illumination 24%

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.

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7 Day Forecast for Marine Location Near National Harbor, MD

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Area Discussion for - Baltimore, MD/Washington

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Fxus61 klwx 251423 afdlwx area forecast discussion national weather service baltimore md washington dc 1023 am edt Sun aug 25 2019 Synopsis Strong high pressure will build north of the region today. Low pressure likely will develop off the carolina coast early in the week and move out to sea by Tuesday. A cold front will cross the region on Wednesday. Near term through tonight High pressure ridging southward to the east of the appalachian mountains will promote dry conditions and northeasterly flow today. Similar to yesterday a fairly widespread cumulus field is expected to develop. A shower or two can't be ruled out either over southern maryland or along the chesapeake bay coastline and adjacent areas later this afternoon and early evening. Temperatures will reach the middle to upper 70s today before dropping into the middle to upper 50s tonight. Short term Monday through Tuesday night High pressure will move out to the northeast Monday and Monday night. A persistent wind from the east or northeast will usher in additional low-level moisture during this period. Dewpoint temperatures, or the indication of the amount of moisture in the air, will gradually rise out of the 50s into the 60s during the day. With this increased moisture and departing high pressure, additional showers are expected to develop not just in the eastern zones but parts of the virginia piedmont, along the blue ridge, and in the potomac highlands Monday afternoon and evening. Temperatures will reach the middle 70s then fall only into the middle 60s Monday night. About the time that showers Monday evening begin to wind down or dissipate, we could have a tropical system lingering off the east coast near the virginia and north carolina shoreline. This system is expected to push onward toward the northeast over the open atlantic Tuesday and Tuesday and not have any path toward the delmarva beaches since there will be an upper level trough approaching from the ohio valley. Although we don't anticipate a direct impact with this system Tuesday into Tuesday night, it could have an effect on our coastal waters of the chesapeake bay and tidal potomac in terms of coastal flooding. Also, showers and perhaps a diurnal thunderstorm or two could evolve in parts of our region. The east to southeast component to the wind expected Tuesday could mean that any modest convection could evolve due to upslope along the blue ridge and potomac highlands. Temperatures Tuesday should approach 80 degrees in most places. Long term Wednesday through Saturday A trough axis crossing the great lakes Wednesday will push a cold front across the mid atlantic. The atmosphere will be sufficiently moist prior to the frontal passage, with respectable instability and modest shear--certainly enough to justify a shower thunderstorm forecast at high chance to maybe likely levels. That said, it is unlikely that it will be an all day rainfall; rather the precipitation FROPA seems to be focused on the timeframe of peak diurnal heating, although the lingering upper trough jet suggests it may not move through quickly. Will be keeping chance pops east of the blue ridge into Wednesday night.

For the rest of the week, continental high pressure building toward the east coast will be the primary weather feature. Consequently temperatures will remain rather mild for late august (highs in the lower-mid 80s, lows mid 50s-mid 60s). Aviation 14z Sunday through Thursday Vfr conditions expected with high pressure to the north then to the northeast by Tuesday. Any showers should be isolated Monday and Tuesday with low confidence as to which terminals may or may not encounter one of these showers. Winds northeast around 10 knots through Monday night. Winds becoming southeasterly around 10 knots Tuesday into Tuesday night. Flight restrictions may linger into Wednesday due to low clouds and perhaps vsby as a result of east flow. Ceilings will gradually lift through the day, but an approaching cold front will support a chance of showers thunderstorms by afternoon evening. While exact convective impact uncertain, odds suggest it wouldn't be widespread or of long duration. But, the lingering moisture could result in restrictions Wednesday night. Thursday should fare better as high pressure builds.VFR likely. Marine A small craft advisory remains in effect for much of the chesapeake bay and tidal potomac through Monday. Depending on the gradient between the high to the north and the developing tropical system along the east coast, additional small craft advisories may be needed Monday night into Tuesday. The pressure gradient likely won't be strong enough to support small craft conditions Wednesday or Thursday. But, a frontal passage late Wednesday will support showers thunderstorms so local marine warnings possible. Tides coastal flooding Water level anomalies on the western shore of the chesapeake bay and along the tidal potomac have continued to trend upward with persistent northeasterly flow. Minor tidal flooding becomes possible tonight through Wednesday, especially as flow turns more easterly and then southeasterly Tuesday into Wednesday. Lwx watches warnings advisories Dc... None. Md... None. Va... None. Wv... None. Marine... Small craft advisory until 6 pm edt Monday for anz531>534- 537>543. Small craft advisory until 6 am edt Monday for anz530-536. Synopsis... Klw near term... Mm klw short term... Klw long term... Hts aviation... Mm hts klw marine... Mm hts klw tides coastal flooding... Mm

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Weather Reporting Stations

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Stations	Dist	Age	Wind	Air Temp	Water Temp	Waves	Pressure	DewPt
WASD2 - 8594900 - Washington, DC	5 mi	53 min	ENE 4.1 G 9.9	74°F	82°F		1023.5 hPa
BSLM2 - Chesapeake Bay, MD	17 mi	113 min	N 2.9	69°F			1023 hPa	62°F
APAM2 - 8575512 - Annapolis, MD	32 mi	53 min		72°F			1022.8 hPa
TPLM2 - Thomas Point, MD	32 mi	83 min	NNE 17 G 21	69°F	79°F		1023.6 hPa (+0.0)	61°F
NCDV2	33 mi	59 min	N 2.9 G 9.9	73°F	81°F		1021.8 hPa
44062 - Gooses Reef, MD	37 mi	77 min	NE 18 G 19	71°F			1023.2 hPa
CPVM2	37 mi	53 min		71°F				61°F
FSKM2 - 8574728 - Francis Scott Key Bridge, MD	39 mi	59 min	ENE 13 G 16	70°F			1023.5 hPa
FSNM2	39 mi	59 min	NE 14 G 17
BLTM2 - 8574680 - Baltimore, MD	40 mi	53 min	ENE 11 G 17	70°F	80°F		1023.3 hPa
COVM2 - 8577018 - Cove Point LNG Pier, MD	44 mi	53 min	ENE 20 G 25	69°F			1023 hPa
SLIM2 - 8577330 - Solomons Island, MD	45 mi	53 min	NNE 16 G 20	70°F	81°F		1021.8 hPa

Wind History for Washington, DC

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N4 G10

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W4 G11

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Airport Reports

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Airport	Dist	Age	Wind kt	Visibility	Sky/Weather	Temp	DewPt	Humidity	Pressure
Washington/Reagan National Airport, DC, VA	4 mi	91 min	NE 13 G 19	10.00 mi	A Few Clouds	73°F	57°F	57%	1023.5 hPa
Camp Springs / Andrews Air Force Base, MD	9 mi	87 min	NNE 12	10.00 mi	Fair	70°F	58°F	67%	1023.6 hPa
Fort Belvoir, VA	9 mi	87 min	NNE 3	10.00 mi	Fair	73°F	56°F	57%	1023.6 hPa
College Park Airport, MD	14 mi	40 min	ENE 12 G 19	10.00 mi	Partly Cloudy	72°F	52°F	51%	1023.4 hPa
Fort Meade / Tipton, MD	24 mi	41 min	ENE 8 G 15	10.00 mi	Fair	72°F	55°F	57%	1024.7 hPa

Link to 5 minute data for KDCA

Wind History from DCA (wind in knots)

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Tide / Current Tables for Alexandria, Virginia

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Tide / Current Tables for Fort Washington, Maryland

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Weather Map and Satellite Images

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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.
Link to Loop

Other links: Northern Pacific     Contential US     Full GOES-East

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Wind Forecast for Baltimore, MD/Washington (11,2,3,4)

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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.