Marine Weather and Tides
5/20/2018 -- NOAA is having problems with the data feed that I use to draw the graphs. They are aware of the issue and working to resolve it. Sometimes changing the location by about a mile will give a correct graph. 3/3/2018 - There is a new GOES Satellite for the east coast that required rewriting that part of the code. Please report any issues.
|Sunrise 5:42AM||Sunset 8:37PM||Thursday June 21, 2018 10:17 AM EDT (14:17 UTC)||Moonrise 1:22PM||Moonset 12:52AM||Illumination 57%|
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|ANZ537 Tidal Potomac From Cobb Island To Smith Point- 731 Am Edt Thu Jun 21 2018 |
.small craft advisory in effect from Friday morning through Friday evening...
Today..N winds 5 kt. Waves less than 1 ft. Isolated showers this afternoon.
Tonight..E winds 5 to 10 kt. Waves 1 to 2 ft. Scattered showers. Vsby 1 nm or less.
Fri..E winds 10 to 15 kt with gusts to 20 kt. Waves 3 ft. Showers likely. Vsby 1 nm or less.
Fri night..E winds 10 to 15 kt with gusts to 20 kt. Waves 2 to 3 ft. Showers likely.
Sat..S winds 5 to 10 kt. Waves 1 to 2 ft. Showers likely.
Sat night..SW winds 5 to 10 kt. Waves 1 ft. Scattered showers and tstms.
Sun..W winds 5 to 10 kt. Waves 1 ft. A chance of tstms through the night. A chance of showers.
Mon..NE winds 5 to 10 kt. Waves 1 to 2 ft. A chance of showers in the morning. Winds and waves higher and visibilities lower in and near tstms.
|ANZ500 731 Am Edt Thu Jun 21 2018 |
Synopsis for the tidal potomac and md portion of the chesapeake bay.. A front will remain stalled over the mid-atlantic into Friday before returning slowly northward as a warm front through Saturday. Meanwhile, low pressure over the ohio valley will move into the eastern great lakes. This low will then move eastward across new england during the second half of the weekend bringing a cold front across the waters. A small craft advisory may be needed for a portion of the waters late Friday night into Saturday.
7 Day Forecast for Marine Location Near St. George Island CDP, MDHourly EDIT Help
Area Discussion for - Baltimore, MD/Washington  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxus61 klwx 211347|
area forecast discussion
national weather service baltimore md washington dc
947 am edt Thu jun 21 2018
A front will remain stalled over the mid-atlantic through
tonight before slowly returning north as a warm front Friday
into Saturday. Low pressure will move from the ohio valley to
the eastern great lakes during this time, then eastward across
new england Sunday bring a cold front across the region. High
pressure will then build in from the eastern great lakes and
remain in control through the middle of next week.
Near term through tonight
A weak cold front will pass through the metro areas late this
morning early this afternoon and it is expected to stall out
later this afternoon across central virginia into the potomac
highlands. An isolated shower is possible with the frontal
passage through midday. Farther south and west across central
virginia into the potomac highlands, more widespread showers and
thunderstorms are expected to develop this afternoon due to
forcing from the boundary and moderate instability from a very
warm and humid airmass in place. Thunderstorms will produce
heavy rainfall later this afternoon across these areas. (see
hydrology section for details on heavy rain threat flash flood
The forward (northeastward) progression of showers tonight may
be hindered some, as the front should remain largely stalled due
to easterly flow developing around high pressure departing off
the new england coast. For this reason, sided with the somewhat
slower NAM sref pops as opposed to the quicker gfs, which keeps
coverage more scattered over much of maryland and the washington
dc baltimore metro areas through much of the night. More heavy
rain is expected across central virginia into the potomac
highlands (closer to the stalled boundary). See hydrology
section for more details.
Short term Friday through Saturday night
Rounds of showers and scattered thunderstorms are expected to
re-invigorate and spread northeastward across virtually the
entire mid-atlantic Friday afternoon into Friday night, before
departing to the northeast Saturday morning along and ahead of
the slowly advancing warm front. See the hydrology section for
details on the heavy rain flooding threat.
Hedging on the side of climatology, the warm front will likely
get stuck near the potomac river Saturday, enhancing low-level
directional shear. Speed shear increasing in the 0-6 km layer to
around 50 knots with around 40 kts at 850 mb. This couple with
abundant low-level moisture should lead to an environment
favorable for scattered strong to severe storms and perhaps a
couple supercells where best instability is pooled over
southeastern parts of the cwa. Gusty winds or an isolated
tornado would be possible in this scenario. SPC has southern
maryland to the fredericksburg virginia area in a marginal risk,
with uncertainties in more robust instability given poor lapse
The warm front should lift further north by Saturday evening,
with waning isentropic lift and diurnally decreasing instability
leading to a decrease in convection overnight.
Long term Sunday through Wednesday
A broad area of low pressure will be moving through new england on
Sunday. One boundary may be located just to our south, but the
stronger cold front will be descending southward from the great
lakes ahead of a sharper upper level trough. These features may
result in some showers and thunderstorms during the afternoon and
evening, but deep layer westerly flow may limit the coverage. Warm
and moderately humid conditions will likely persist ahead of the
While some ensemble members have a slower frontal progression
through the area on Monday, the 00z deterministic models have it
south of the area. In addition, the upper level trough axis vort max
is now progged to be centered more over new england. Thus the
forecast will trend cooler and drier.
By Tuesday, there is good model agreement on high pressure building
in from the northwest, resulting in dry weather and near to slightly
below normal temperatures. The high will begin to move offshore
Wednesday. Temperatures will begin to rebound, but precipitation
chances will remain low.
Aviation 14z Thursday through Monday
MVFR CIGS are likely through midday across the northern
terminals before eventually lifting towardVFR levels. An
isolated shower is possible as well. More widespread showers
and thunderstorms will develop near kcho later this afternoon
and evening. Farther north and east, lighter rain is possible
late this evening.
Winds will generally be NE AOB 10 kts through tonight before
increasing Friday with gusts around 20 kts possible.
Showers accompanying restrictions also become more widespread
late tonight through Friday night before diminishing early
Saturday as winds become southwesterly in the wake of an
advancing warm front. Scattered strong convection is possible
Saturday afternoon, but predominatelyVFR is expected.
Showers and thunderstorms will be possible Sunday afternoon and
evening as a cold front moves toward the region.VFR conditions are
expected Monday as the front moves to the south.
Sca posted Friday Friday evening in increasing easterly flow.
Otherwise generally light winds expected outside of perhaps more
isolated SW gusts Saturday. Isolated stronger convection could
result in localized higher wind gusts Saturday afternoon and
evening as well.
West winds on Sunday will become northerly by Monday as a cold front
pushes south through the waters. Wind speeds are still a bit
uncertain at this time, but they could be near small craft advisory
thresholds. Thunderstorms will also be possible ahead of the front
Sunday afternoon and evening.
Pwats exceeding 2-2.25 inches by this evening over central
virginia is quite concerning given potential repeated rounds of
convection with a front stalled overhead. Also, 925-850 mb flow
increases out of the east to 25-30 kts increasing moisture
advection and resulting in an upslope component. Rainfall
amounts by Friday morning will average 1 to 3 inches, with
locally much higher amounts possible. A flash flood watch is in
effect for central virginia into the potomac highlands later this
afternoon through tonight.
The heavy rain threat spreads further northeastward Friday
afternoon and night as the warm front advances. Additional
watches may be required.
Tides coastal flooding
Tidal anomalies have risen slightly to around a half foot, but
should remain steady through today with light northerly wind.
Afterward, easterly winds will develop and result in further rises.
If the surge is quick, some sensitive locations may approach minor
flood thresholds Friday night, although most guidance has peak
anomalies and the highest chance of minor flooding Saturday night
after winds turn southerly. A cold frontal passage will end the
threat on Sunday.
Lwx watches warnings advisories
Va... Flash flood watch from 3 pm edt this afternoon through late
tonight for vaz025-026-029-036>040-050-051-503-504-507-
Wv... Flash flood watch from 3 pm edt this afternoon through late
tonight for wvz505-506.
Marine... Small craft advisory from 6 am Friday to midnight edt Friday
night for anz530>543.
near term... Bjl dhof
short term... Dhof
long term... Ads
aviation... Bjl ads dhof
marine... Bjl ads dhof
hydrology... Dhof bjl
tides coastal flooding... Dhof
Weather Reporting StationsEDIT (on/off)  Help NOTE: Click on distance to see the station location on a map
|Stations||Dist||Age||Wind||Air Temp||Water Temp||Waves||Pressure||DewPt|
|LWTV2 - 8635750 - Lewisetta, VA||4 mi||47 min||NNW 4.1 G 6||77°F||81°F||1008.4 hPa|
|PPTM2 - 8578240 - Piney Point, MD||7 mi||53 min||NNW 6 G 7|
|SLIM2 - 8577330 - Solomons Island, MD||20 mi||47 min||WNW 2.9 G 6||77°F||79°F||1008 hPa|
|COVM2 - 8577018 - Cove Point LNG Pier, MD||26 mi||47 min||N 2.9 G 4.1||75°F||1008.8 hPa|
|BISM2 - 8571421 - Bishops Head, MD||27 mi||47 min||WSW 7 G 9.9||76°F||82°F||1008.7 hPa|
|NCDV2||34 mi||47 min||WSW 2.9 G 4.1||77°F||81°F||1007.5 hPa|
|44058 - Stingray Point, VA||35 mi||37 min||NNW 3.9 G 5.8||78°F||1011 hPa|
|44062 - Gooses Reef, MD||36 mi||37 min||NNW 3.9 G 3.9||76°F||1010 hPa|
|CA2 - 8571892 - Cambridge, MD||43 mi||47 min||80°F||81°F||1009 hPa|
|RPLV2 - 8632837 - Rappahannock Light, VA||43 mi||47 min||WNW 2.9 G 4.1||1009.1 hPa|
|YRSV2 - Chesapeake Bay,VA||45 mi||47 min||W 1.9||85°F||1009 hPa||82°F|
Wind History for Lewisetta, VA(wind in knots) EDIT (on/off)  Help
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports
|St. Inigoes, Webster Field, Naval Electronic Systems Engineering Activity, MD||8 mi||24 min||WSW 4||mi||Mostly Cloudy||79°F||73°F||82%||1007.8 hPa|
|Patuxent River, Naval Air Station, MD||18 mi||85 min||NNW 6||10.00 mi||Mostly Cloudy||81°F||72°F||74%||1008.1 hPa|
|St Marys County Airport, MD||19 mi||40 min||WSW 3||10.00 mi||Mostly Cloudy||77°F||71°F||83%||1008.8 hPa|
|Tappahannock-Essex County Airport, VA||24 mi||22 min||NW 3||10.00 mi||Partly Cloudy||79°F||73°F||84%||1008.8 hPa|
Wind History from NUI (wind in knots)
|1 day ago||W||W||W||W||W||NE||NE||SW||W||SW||W||W||Calm||W||Calm||Calm||Calm||N||N||Calm||N||Calm|
|2 days ago||E||S||S||S||SE||SE||SE||S||S||S||S||S||SW||SW||S||S||W||Calm||W||SW||W||W |
EDIT RT Ports Option Weekend mode (on/off) (on/off)  Help One Week of Data
|Lynch Point |
Click for Map
Thu -- 01:52 AM EDT Moonset
Thu -- 03:26 AM EDT 0.12 feet Low Tide
Thu -- 05:43 AM EDT Sunrise
Thu -- 09:29 AM EDT 1.44 feet High Tide
Thu -- 02:22 PM EDT Moonrise
Thu -- 03:43 PM EDT 0.06 feet Low Tide
Thu -- 08:32 PM EDT Sunset
Thu -- 10:03 PM EDT 1.57 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
EDIT (on/off)  Help One Week of Data
|Point Patience |
Click for MapFlood direction 315° true
Ebb direction 145° true
Thu -- 12:39 AM EDT -0.68 knots Max Ebb
Thu -- 01:52 AM EDT Moonset
Thu -- 04:36 AM EDT 0.00 knots Slack
Thu -- 05:42 AM EDT Sunrise
Thu -- 06:20 AM EDT 0.36 knots Max Flood
Thu -- 08:30 AM EDT -0.00 knots Slack
Thu -- 12:39 PM EDT -0.86 knots Max Ebb
Thu -- 02:22 PM EDT Moonrise
Thu -- 04:42 PM EDT 0.00 knots Slack
Thu -- 07:04 PM EDT 0.61 knots Max Flood
Thu -- 08:32 PM EDT Sunset
Thu -- 10:01 PM EDT -0.00 knots Slack
Tide / Current data from XTide NOT FOR NAVIGATION
Weather Map and Satellite Images(on/off)  HelpWeather Map
GOES Local Image of Mid-Atlantic 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.
target = "new">Link to Loop
Other links: Northern Pacific Contential US Full GOES-East
Wind Forecast for Baltimore, MD/Washington (10,2,3,4)(on/off)  Help
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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.