Tuesday, October22, 2019 L-36.com


Marine Weather and Tides
National Harbor, MD

Version 3.4
NOTICE
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.
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

Sunrise 7:23AMSunset 6:22PM Tuesday October 22, 2019 7:33 PM EDT (23:33 UTC) Moonrise 12:00AMMoonset 2:23PM Illumination 31% Phase: Waning Crescent; Moon at 24 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- 436 Pm Edt Tue Oct 22 2019
.small craft advisory in effect through late tonight...
Rest of this afternoon..SE winds 5 kt. Waves less than 1 ft. Showers. Vsby 1 to 3 nm.
Tonight..NW winds 5 to 10 kt. Gusts up to 20 kt in the late evening and early morning. Waves 1 ft. Showers. Vsby 1 to 3 nm.
Wed..W winds 5 to 10 kt. Waves 1 ft.
Wed night..W winds around 5 kt. Waves 1 ft or less.
Thu..S winds around 5 kt. Waves 1 ft or less.
Thu night..SW winds around 5 kt. Waves 1 ft or less.
Fri..NW winds around 5 kt. Waves 1 ft.
Sat..E winds 5 kt. Waves less than 1 ft.
ANZ500 436 Pm Edt Tue Oct 22 2019
Synopsis for the tidal potomac and md portion of the chesapeake bay.. A cold front will cross the waters through this evening. High pressure will build from the mid-south across the mid-atlantic then off the new england coast Wednesday through Thursday night. A cold front may approach from the ohio valley Friday, then an area of low pressure may approach from the tennessee valley over the weekend.


7 Day Forecast for Marine Location Near National Harbor, MD
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location: 38.8, -77.03     debug


Area Discussion for - Baltimore, MD/Washington
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Fxus61 klwx 221919
afdlwx
area forecast discussion
national weather service baltimore md washington dc
319 pm edt Tue oct 22 2019

Synopsis
A cold front will cross the region this evening. High pressure
will build from the mid-south across the mid-atlantic then off
the new england coast Wednesday through Thursday night. A cold
front will approach from the ohio valley Friday, then an area
of low pressure will approach from the tennessee valley over
the weekend.

Near term until 6 am Wednesday morning
Areas of rain are ongoing across the area in association with a
broad swath of warm advection aloft. With the thick cloud deck
in place and rain falling, conditions are stable at the surface.

As a result, we aren't anticipating any surface based storms. A
couple of rumbles of thunder can't be ruled out as some meager
instability is present aloft. With the stable layer present near
the surface, mixing down of higher winds from aloft will be
inhibited. If a stronger convective element were to form, a
brief stronger wind gust can't be ruled out, but that isn't
anticipated at this time. The rain should predominantly be light
to moderate in nature, but intermittent heavier downpours will
remain possible.

The surface cold front will progress through the area late this
afternoon through the evening, bringing an end to the rain.

Winds will shift around to west-northwesterly in the wake of the
front, and clouds will gradually clear out as well. Low
temperatures tonight will bottom out in the 40s to near 50.

Short term 6 am Wednesday morning through Thursday night
High pressure will gradually build in from the southwest during
the day Wednesday, before shifting offshore on Thursday. This
will lead to dry conditions, with mostly sunny skies and
seasonable temperatures. Winds will be out of the west on
Wednesday, then shift around to light out of the south on
Thursday as high pressure moves offshore. Patchy frost may be
possible Wednesday night in the typically cooler spots as winds
go calm with high pressure centered overhead.

Long term Friday through Tuesday
Model guidance remains split as far as what happens across the
area next weekend. At this point, Friday looks to remain dry and
seasonable, no matter what model guidance you look at. This due
to high pressure building into the region. By Friday night, a
shortwave sliding by to the north will bring a slight chance for
precipitation. Low temperatures Friday night will be in the mid
40s.

Keeping slight chance pops in the forecast on Saturday, but
think we could very well stay completely dry. The only set of
guidance that brings rain in on Saturday is the GFS and its
ensembles (gefs). The ecmwf, eps ensembles, and the cmc all
develop a cutoff low over the southwest u.S. That slowly makes
its way towards the east through the weekend. Whereas the
gfs GEFS keeps an open trough that moves east more quickly, thus
bringing rain in for Saturday. Going with the ECMWF cmc pair at
this point, as it has been fairly consistent, and the 12z gfs
seems to be starting a slower trend finally. So, thinking
Saturday and Saturday night should remain dry, but keeping
slight chance pops in for the time being. To that same point,
will likely be doing the same for the first half of Sunday, as
the ECMWF cmc don't bring rain until late Sunday or even early
Monday, as a surface low develops and moves across the great
lakes. Given the lesser chance for precip Saturday Sunday, will
likely be a little warmer than previously forecast. Thinking
highs closer to the mid 60s.

The cold front associated with the aforementioned surface low
will push through on Monday as high pressure pushes offshore. As
a result, high temperatures in the mid to upper 60s to near 70
seem reasonable ahead of the front, assuming it doesn't pass
early in the day. The front will hang up across the region later
in the day, with showers expected to continue.

Aviation 19z Tuesday through Sunday
Cigs are currently ifr or very low-end MVFR at all of the
terminals. CIGS are expected to bounce between ifr and low-end
MVFR until a cold front passes through the area this evening.

Showers, with some embedded heavier bursts of rain will be
possible in advance of this front through the remainder of the
afternoon. The front will progress through the terminals from
west to east between approximately 22z and 01z. As the front
moves through, conditions will clear out, with ceilings rising,
rain coming to an end, and winds shifting around from SE to nw.

Vfr conditions are expected in the wake of the front tonight
through Thursday, with westerly flow eventually switching around
to light southerly flow on Thursday.

Likely to seeVFR conditions Friday and Saturday, with high
pressure building overhead.

Marine
Sporadic SCA gusts will be possible in south-southeasterly flow
over the next couple hours. Winds are expected to relax briefly
late this afternoon into early evening, before picking back up
again out of the northwest in the wake of the front. Winds will
gradually relax through the afternoon tomorrow, but some sca
gusts may still be possible over the bay in westerly flow. Winds
are expected to be remain light on Thursday with high pressure
moving overhead.

With high pressure building overhead Friday into Saturday, winds
will remain below SCA criteria. As high pressure begins to
shift offshore on Saturday, could see winds pick up out of the
south, but not expected to reach SCA criteria at this time.

Tides coastal flooding
Anomalies have been relatively stable but are now high enough to
warrant warnings for the sensitive points (annapolis straits)
and advisories all other zones. They should decline tomorrow as
winds turn northwesterly, but as the flow behind the system
isn't all that strong, they may not go down a whole lot, so will
need to monitor the drop closely.

Additional issues may crop up this weekend depending on the
development of another low pressure system approaching from the
southwest.

Lwx watches warnings advisories
Dc... Coastal flood advisory until 9 am edt Wednesday for dcz001.

Md... Coastal flood warning from 6 pm this evening to 7 am edt
Wednesday for mdz014.

Coastal flood advisory until 6 pm edt this evening for mdz014.

Coastal flood advisory from 7 pm this evening to 2 am edt
Wednesday for mdz016.

Coastal flood warning until 2 am edt Wednesday for mdz017.

Coastal flood advisory until 8 am edt Wednesday for mdz508.

Coastal flood advisory until 6 am edt Wednesday for mdz011.

Va... Coastal flood advisory from 7 pm this evening to 2 am edt
Wednesday for vaz057.

Coastal flood advisory until 9 am edt Wednesday for vaz054.

Wv... None.

Marine... Small craft advisory until 6 pm edt Wednesday for anz530>534-
537>543.

Small craft advisory until 6 am edt Wednesday for anz535-536.

Synopsis... Kjp
near term... Kjp
short term... Kjp
long term... Cjl
aviation... Cjl kjp
marine... Cjl kjp
tides coastal flooding... Rcm


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
WASD2 - 8594900 - Washington, DC 5 mi51 min ESE 1.9 G 5.1 61°F 62°F1009 hPa
BSLM2 - Chesapeake Bay, MD 17 mi123 min WNW 6 62°F 1009 hPa62°F
APAM2 - 8575512 - Annapolis, MD 32 mi45 min 61°F 1009.3 hPa
TPLM2 - Thomas Point, MD 32 mi33 min NW 8 G 8.9 61°F 63°F1010.8 hPa (+0.7)61°F
44063 - Annapolis 33 mi33 min N 5.8 G 7.8 61°F 63°F1 ft1009.8 hPa (+0.4)
NCDV2 33 mi51 min N 2.9 G 5.1 60°F 1008.1 hPa
44062 - Gooses Reef, MD 37 mi27 min N 14 G 14 61°F 1010.7 hPa
CPVM2 37 mi51 min 62°F
FSKM2 - 8574728 - Francis Scott Key Bridge, MD 39 mi45 min NW 4.1 G 4.1 61°F 1009.7 hPa
FSNM2 39 mi57 min NW 2.9 G 5.1 61°F 1009.5 hPa
BLTM2 - 8574680 - Baltimore, MD 40 mi51 min WSW 1.9 G 1.9 61°F 66°F1009.2 hPa
SLIM2 - 8577330 - Solomons Island, MD 45 mi45 min NNW 7 G 12 64°F 65°F1009 hPa

Wind History for Washington, DC
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Washington/Reagan National Airport, DC, VA4 mi41 minE 410.00 miOvercast61°F59°F93%1009.2 hPa
Camp Springs / Andrews Air Force Base, MD9 mi37 minENE 310.00 miOvercast59°F59°F99%1009.7 hPa
Fort Belvoir, VA9 mi37 minN 010.00 miOvercast60°F57°F94%1009.4 hPa
College Park Airport, MD14 mi50 minN 010.00 miOvercast59°F56°F93%1009.1 hPa
Fort Meade / Tipton, MD24 mi51 minN 07.00 miOvercast59°F59°F100%1010.8 hPa

Link to 5 minute data for KDCA

Wind History from DCA (wind in knots)
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Last 24hrS6S8E7S6S8S5S5S7S7SE6S6S7S8S9S9S9SE9S11SE12S7CalmNW9N7E4
1 day agoN13N12N11N10N10N8N12N11N9N11N13N11N9N7NE6N5NE3CalmCalmN33S4S3SE8
2 days agoSE4S4S5S3SE4S5S4S4S4CalmCalmN4NE8NE9NE9NE12NE16NE15NE15N14
G21
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Tide / Current Tables for Alexandria, Virginia
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Alexandria
Click for Map
Tue -- 12:37 AM EDT     Moonrise
Tue -- 02:38 AM EDT     3.05 feet High Tide
Tue -- 07:24 AM EDT     Sunrise
Tue -- 10:00 AM EDT     0.46 feet Low Tide
Tue -- 03:23 PM EDT     Moonset
Tue -- 03:32 PM EDT     2.70 feet High Tide
Tue -- 06:20 PM EDT     Sunset
Tue -- 10:02 PM EDT     0.45 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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1.92.6332.82.31.81.30.90.60.50.61.11.92.42.72.72.41.91.30.90.60.50.6

Tide / Current Tables for Riverview, Potomac River, Maryland
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Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.


Weather Map
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wmap_A
GEOS 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.
Link to Loop



Other links: Northern Pacific     Contential US     Full GOES-East
Wind Forecast for Baltimore, MD/Washington (19,4,5,8)
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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.