Monday, May29, 2017 L-36.com


Marine Weather and Tides
Olney, MD

Version 3.4
What's New / NOTES
5/23/2017 - Worked with NOAA again to speed up the 7 day forecast load times. Thanks to them for being responsive.
5/19/2016 - There were issues with the 3 day airport observation history. I switched to another data source. Let me know if you see any issues with the data feeds.

Sunrise 5:43AMSunset 8:28PM Monday May 29, 2017 1:51 AM EDT (05:51 UTC) Moonrise 8:50AMMoonset 11:17PM Illumination 14% Phase: Waxing Crescent; Moon at 4 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- 146 Am Edt Mon May 29 2017
Overnight..NE winds around 5 kt. Waves 1 ft. Scattered showers with patchy drizzle. Patchy fog. Vsby 1 to 3 nm.
Mon..W winds 5 to 10 kt. Waves 1 ft. Scattered showers with patchy drizzle. Patchy fog. Vsby 1 nm or less.
Mon night..E winds around 5 kt. Waves 1 ft.
Tue..S winds around 5 kt. Waves 1 ft. A chance of showers.
Tue night..SW winds 5 kt. Waves less than 1 ft. A chance of showers.
Wed..W winds 5 to 10 kt. Waves 1 ft.
Wed night..W winds 5 kt. Waves less than 1 ft.
Thu..S winds around 5 kt. Waves 1 ft.
Fri..W winds around 5 kt. Waves 1 ft. A chance of showers.
ANZ500 146 Am Edt Mon May 29 2017
Synopsis for the tidal potomac and md portion of the chesapeake bay.. A stationary front will remain south of the waters until a cold front moves into the area Monday. Weak high pressure can be expected Tuesday, followed by another weak front Wednesday. High pressure will return Thursday.

7 Day Forecast for Marine Location Near Olney, MD
   Hourly   EDIT   Help
location: 39.15, -77.07     debug


Area Discussion for - Baltimore, MD/Washington
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
Fxus61 klwx 290107
afdlwx
area forecast discussion
national weather service baltimore md washington dc
907 pm edt Sun may 28 2017

Synopsis
A boundary remains over northern north carolina. Upper level
low pressure will drift east across the north side of the great
lakes Monday through Friday. In the meantime, weak high pressure
will prevail over the mid atlantic outside of weak trough
passages Tuesday night and Wednesday night. Low pressure
approaches from the west this weekend.

Near term overnight
Areas of light rain will continue for the next several hours.

Should clearing occur behind the low to our south, fog would be
expected.

Mid 60s min temps tonight which are near dewpoints.

Short term Monday through Tuesday night
Weak trough moves east across the area in the morning with
advance showers ending by noon for the western shore of the bay.

14 to 15c 850mb temps mix down in light westerly flow making
for MAX temps low to mid 80s. The lack of rain and clouds will
make for a marked difference from today!
weak surface high pressure lingers over the area as the parent
upper low drifts east across the north side of the great lakes.

A few shortwaves look to round the low and disrupt the tranquil
weather. The first looks to be Tuesday night so low chance pops
for showers were added then. Otherwise slightly above normal
temps persist.

Long term Wednesday through Sunday
A weak front across the region could spawn a couple of showers or a
thunderstorm in parts of the region Wednesday into Wednesday evening.

Weak high pressure will build in Wednesday night through Thursday
night. Dry conditions and seasonable temperatures expected.

The high moves east Friday to allow for a leeside trough of low
pressure to form east of the potomac highlands Friday night. There
is a chance for rain showers along this trough both Friday and
Friday night. Temperatures will be near normal.

There is a better chance for rain showers and perhaps a few
thunderstorms Saturday into Saturday night as a disturbance moves
into the region to accompany the trough of low pressure.

By Sunday, a cold front should work into the region and bring an
additional threat for showers and thunderstorms.

Aviation 01z Monday through Friday
MVFR CIGS vsbys across the dc metros with rain tapering off
(except for kmrb and west) after midnight as low pressure
passes to the south. Fog will develop in any areas that clear.

Weak trough crosses from the west late tonight with light west
winds andVFR Monday into Tuesday. A weak trough crosses late
Tuesday with chances for rain then.

Vfr conditions at the terminals, except where pop-up showers or
a thunderstorm develop Wednesday and Wednesday night. MVFR or
ifr conditions in rainfall. Winds west-southwest 10 knots
Wednesday becoming northwest 5 to 10 knots Wednesday night.VFR
conditions Thursday and Thursday night. Winds northwest 5 to 10
knots Thursday, becoming light and variable Thursday night.

Marine
Light sely flow with low pressure over southern va. Weak trough
crosses from the west Monday morning with light westerly flow
Monday into Tuesday.

No marine hazards expected Wednesday through Thursday night. Winds
southwest 10 knots Wednesday becoming northwest 10 knots Wednesday
night. Winds northwest 5 to 10 knots Thursday then light and
variable Thursday night.

Tides coastal flooding
Water levels running within a few inches of a foot this
afternoon. Light onshore flow should keep the departure similar
through tonight, if not rising slightly. Since we've just passed
the new moon, there is a decent spread in the semi-diurnal
cycle... With the daytime cycle preferred. Current guidance
indicates that we'll hit minor flood during this cycle for the
next couple of days. However, departures a bit greater at piney
point, such that each cycle should hit minor. It'll be a similar
story at SW dc, and perhaps alexandria as well.

Have made some advisory adjustments, based on the above
guidance and thinking. Included the next two cycles for the
upper potomac, the next three cycles (through Monday night) for
st marys (ultimately, the threat there will last longer), and
the second cycle (Monday morning) in calvert anne arundel. No
additional forecasted flooding at this time. Will need to
monitor dahlgren and baltimore, both of which will come close to
minor on Monday.

Ensembles suggest a gradual decrease in water level by midweek.

Lwx watches warnings advisories
Dc... Coastal flood advisory until 2 pm edt Monday for dcz001.

Md... Coastal flood advisory from 3 am to 1 pm edt Monday for mdz014-
018.

Coastal flood advisory until 10 pm edt Monday for mdz017.

Va... Coastal flood advisory until 2 pm edt Monday for vaz054.

Wv... None.

Marine... None.

Update... Woody!
previous... Baj hts 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 19 mi51 min ESE 1.9 G 4.1 65°F 67°F1009 hPa (-0.7)
BLTM2 - 8574680 - Baltimore, MD 27 mi51 min ESE 6 G 8.9 63°F 68°F1009.3 hPa (-1.0)
FSNM2 29 mi51 min ENE 8.9 G 9.9 62°F 1009.4 hPa (-1.1)
FSKM2 - 8574728 - Francis Scott Key Bridge, MD 29 mi51 min ENE 7 G 8 63°F 1009.6 hPa (-1.0)
APAM2 - 8575512 - Annapolis, MD 33 mi51 min 63°F 1009.1 hPa (-0.9)
44063 - Annapolis 35 mi41 min ENE 9.7 G 12 64°F 1009.6 hPa
44043 - Patapsco, MD 36 mi41 min ENE 9.7 G 12 62°F 1010.3 hPa
TPLM2 - Thomas Point, MD 38 mi51 min ENE 7 G 7 63°F 65°F
TCBM2 - 8573364 - Tolchester Beach, MD 44 mi51 min ENE 1 G 5.1 62°F 67°F1010.1 hPa (-0.9)

Wind History for Washington, DC
(wind in knots)    EDIT      (on/off)   Help
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
AM
1
AM
Last
24hr
E1
--
E1
--
NE2
--
NE3
SE3
SE4
G7
SE7
G10
SE4
G7
SE3
G6
E1
G5
--
E2
G5
--
N2
NE1
SE1
G5
E3
--
N1
E2
SE2
1 day
ago
--
--
--
--
--
--
--
--
--
--
--
NE2
NE2
SE2
SE1
G5
NE2
G6
E1
G4
--
S2
N1
--
N2
NE3
2 days
ago
SW3
SW3
SW4
SW4
G7
W5
W6
G12
W6
G12
W11
G16
W11
G17
NW9
G21
NW14
G19
NW9
G20
NW10
G15
NW7
G15
NW11
G15
NW4
G9
NW6
G9
NW1
G4
--
--
S1

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Gaithersburg - Montgomery County Airport, MD5 mi55 minVar 410.00 miOvercast63°F62°F97%1012.3 hPa
College Park Airport, MD14 mi78 minN 010.00 miOvercast64°F61°F95%1009.8 hPa
Fort Meade / Tipton, MD16 mi78 minENE 37.00 miOvercast61°F60°F100%1010.8 hPa
Washington/Reagan National Airport, DC, VA20 mi59 minENE 710.00 miLight Rain65°F64°F97%1009.5 hPa
Baltimore, Baltimore-Washington International Airport, MD21 mi57 minE 810.00 miOvercast62°F62°F100%1009.6 hPa
Washington/Dulles International Airport, DC, VA24 mi59 minE 41.50 miLight Drizzle Fog/Mist64°F63°F96%1009.3 hPa

Wind History from GAI (wind in knots)
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
AM
1
AM
Last 24hrCalmCalmCalmCalmCalmCalmCalmCalm5E84SE10SE3SE74344Calm3E4CalmCalm4
1 day agoCalmCalmCalmCalmSE3CalmCalmCalmCalmS4CalmCalmCalmSE3CalmCalmCalmCalmCalm3CalmCalmCalmCalm
2 days agoCalmCalmW6W4W6W6W10W8
G14
W14
G17
W12
G19
W12
G19
W9
G15
W16
G19
NW15
G21
W9
G24
W19
G31
W15
G22
NW11
G23
NW12
G18
NW5CalmCalmCalmCalm

Tide / Current Tables for Chain Bridge, D.C.
   EDIT   RT Ports Option   Weekend mode (on/off)   (on/off)   Help   One Week of Data
Chain Bridge
Click for Map
Mon -- 05:46 AM EDT     Sunrise
Mon -- 06:31 AM EDT     0.16 feet Low Tide
Mon -- 09:51 AM EDT     Moonrise
Mon -- 12:05 PM EDT     3.70 feet High Tide
Mon -- 07:20 PM EDT     -0.04 feet Low Tide
Mon -- 08:26 PM EDT     Sunset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
3.332.41.71.10.60.20.20.71.72.83.53.73.52.92.21.50.90.4-00.10.81.82.6

Tide / Current Tables for Chain Bridge, Washington, D.C.
   EDIT      (on/off)   Help   One Week of Data
Chain Bridge
Click for Map
Mon -- 05:46 AM EDT     Sunrise
Mon -- 06:33 AM EDT     0.18 feet Low Tide
Mon -- 09:51 AM EDT     Moonrise
Mon -- 12:06 PM EDT     3.65 feet High Tide
Mon -- 07:22 PM EDT     -0.02 feet Low Tide
Mon -- 08:26 PM EDT     Sunset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
3.332.41.71.10.60.30.20.71.72.73.43.63.52.92.21.60.90.400.10.81.72.6

Weather Map and Satellite Images
       (on/off)   Help
Weather Map
wmap_A
IR Satellite Image from GEOS
east_satellite

GOES Local Image of Mid-Atlantic    EDIT
Geos

Wind Forecast for Baltimore, MD/Washington (1,6,7,8)
      (on/off)   Help

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

Ad by Google

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.