Monday, January22, 2018 L-36.com


Marine Weather and Tides
North Chevy Chase, MD

Version 3.4
What's New / NOTES
6/25/2017 - NOAA is having a major issue that impact the 7 day forecast load times. Many users are reporting problems. The issue has been reported.
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 7:20AMSunset 5:20PM Monday January 22, 2018 9:09 PM EST (02:09 UTC) Moonrise 10:31AMMoonset 10:48PM Illumination 38% Phase: Waxing Crescent; Moon at 6 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- 632 Pm Est Mon Jan 22 2018
.small craft advisory in effect from 1 am est Tuesday through Tuesday afternoon...
Tonight..S winds 10 to 15 kt. Gusts up to 20 kt late this evening and overnight. Waves 1 ft. Widespread showers after midnight.
Tue..S winds 10 to 15 kt...becoming W in the afternoon. Gusts up to 25 kt. Waves 1 ft. Widespread showers with a chance of tstms.
Tue night..W winds 5 to 10 kt. Gusts up to 20 kt in the evening. Waves 1 ft.
Wed..NW winds 5 to 10 kt with gusts to 20 kt. Waves 1 ft.
Wed night..NW winds 5 to 10 kt. Waves 1 ft.
Thu..NW winds 5 to 10 kt. Waves 1 ft.
Thu night..N winds around 5 kt. Waves 1 ft.
Fri..S winds around 5 kt. Waves 1 ft.
Sat..S winds 5 to 10 kt. Waves 1 ft. A chance of showers through the night. Winds and waves higher and visibilities lower in and near tstms.
ANZ500 632 Pm Est Mon Jan 22 2018
Synopsis for the tidal potomac and md portion of the chesapeake bay.. A cold front will approach the area tonight and cross the area Tuesday. This will be followed by another area of high pressure for the second half of the week. Small craft advisories will likely be needed Tuesday night through Thursday, with gales possible Tuesday with the frontal passage.

7 Day Forecast for Marine Location Near North Chevy Chase, MD
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location: 39, -77.09     debug


Area Discussion for - Baltimore, MD/Washington
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Fxus61 klwx 230135
afdlwx
area forecast discussion
national weather service baltimore md washington dc
835 pm est Mon jan 22 2018

Synopsis
A cold front will cross the area on Tuesday. High
pressure then builds over the area Tuesday night through Friday
morning then shifts offshore this weekend as another frontal
system approaches from the west.

Near term through Tuesday
Low pressure (both at the surface and aloft) will track into
the great lakes tonight and the cold front associated with the
low will pass through the ohio valley. A southerly flow ahead of
the boundary will strengthen overnight... And this will allow
for more mild conditions along with deeper moisture from the
gulf of mexico. A strengthening low-level jet ahead of the cold
front along with the deep moisture will cause showers to
increase in coverage... Especially after midnight.

Models are showing strong forcing (200-meter 12 hr height
falls) over the area with pwats rising to around to 1.5 inches
or 250 to 400% of normal. In addition, wind fields will also
strengthen with models showing 850 mb and 500 mb winds of 50kt
and 80 kt respectively. With the substantial increase in winds
and moisture, there will be potential for t-storms Tue morning
through midday (12z-18z time frame). Stability indices and the
shrb (high shear low CAPE parameter) suggest potential for
severe t-storms given up to 500 j kg of CAPE and strong wind
fields just above the surface with a line of showers
accompanying sfc cdfnt. Biggest threat for severe t-storms is
east of the u.S. Route 15 corridor. Cdfnt will push east of the
ches bay by 18z with showers ending, but over the appalachians
the showers will continue and turn into snow showers.

A downsloping flow and increasing sunshine may offset cold
advection for a period Tuesday afternoon. Temps in the 50s and
60s are most likely.

Short term Tuesday night through Wednesday night
Turning colder Tue night under CAA pattern. Snow showers will
continue over the mtns with a few inches of accumulation
possible. A northwest flow ahead of approaching high pressure
will allow for dry conditions east of the allegheny highlands
along with seasonably chilly temps.

Long term Thursday through Monday
Dry conditions with near normal temperatures are expected for
Thursday and Friday as high pressure moves south or near our
area. Flow will change from northerly to southerly as the high
pressure moves offshore on Friday. Warm air advection will allow
temperatures to become above normal, especially for Saturday -
maybe Sunday- with some areas reaching the 50s.

Guidance suggests that a cold front will move through sometime late
Saturday or Sunday. Timing of the frontal passage and amount of qpf
is still uncertain but trending more into a Sunday event. Showers
associated to this could begin Saturday night. Behind the front, dry
conditions and cooler temperatures expected, with temperatures
dropping to near normal.

Aviation 01z Tuesday through Saturday
Developing ifr conditions mainly 06z-15z Tue with showers with
a slight chance of tsra. Llws also a possibility 06-15z. Cdfnt
pushes east of terminals after 15z with winds shifting and
showers ending.

Vfr conditions expected between Thursday and Saturday with high
pressure moving south or near our area.

Marine
Winds will strengthen tonight into Tue morning with
sca conditions. Showers or t-storms Tue morning may be capable
of producing brief strong convective gusts in excess of 33 kt
which may require smws. SCA conditions will likely persist
through wed.

Wind gusts could reach small craft advisory criteria on
Thursday before decreasing into Friday. Breezy conditions return
on Saturday with the cold front.

Tides coastal flooding
A southerly wind will strengthen tonight into Saturday morning.

Tidal anomalies will increase... But astronomical norms are low
due to the lunar phase. Therefore... Minor flooding is not
expected but it will be close for sensitive areas Tuesday
morning. An offshore flow will develop Tuesday afternoon behind
a cold front.

Lwx watches warnings advisories
Dc... None.

Md... None.

Va... None.

Wv... None.

Marine... Small craft advisory from 1 am Tuesday to midnight est Tuesday
night for anz530>532-535-536-538>541.

Small craft advisory until midnight est Tuesday night for
anz533-534-537-542-543.

Synopsis... Lfr
near term... Bjl lfr
short term... Lfr
long term... Imr
aviation... Bjl imr lfr
marine... Bjl imr lfr
tides coastal flooding... Bjl


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
WASD2 - 8594900 - Washington, DC 10 mi51 min SSE 5.1 G 7 56°F 35°F1015.8 hPa
BSLM2 - Chesapeake Bay, MD 25 mi159 min SSE 5.1 52°F 1017 hPa45°F
APAM2 - 8575512 - Annapolis, MD 32 mi51 min 44°F 1016.4 hPa
FSKM2 - 8574728 - Francis Scott Key Bridge, MD 33 mi51 min SSE 11 G 12 50°F 1016.1 hPa
BLTM2 - 8574680 - Baltimore, MD 33 mi51 min S 4.1 G 8.9 49°F 34°F1015.8 hPa
FSNM2 34 mi51 min S 13 G 20 54°F 1015.7 hPa
TPLM2 - Thomas Point, MD 35 mi69 min SSW 9.9 G 9.9 42°F 34°F
CPVM2 37 mi51 min 40°F 37°F
NCDV2 47 mi51 min SE 8 G 9.9 42°F 37°F1015.2 hPa
TCBM2 - 8573364 - Tolchester Beach, MD 47 mi51 min SSE 5.1 G 7 54°F 34°F1016.8 hPa

Wind History for Washington, DC
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
College Park Airport, MD9 mi72 minN 010.00 miFair58°F42°F57%1015.9 hPa
Washington/Reagan National Airport, DC, VA10 mi77 minSSE 710.00 miOvercast55°F43°F64%1016 hPa
Gaithersburg - Montgomery County Airport, MD12 mi73 minSE 1010.00 miFair56°F43°F62%1018.8 hPa
Camp Springs / Andrews Air Force Base, MD17 mi73 minSSE 810.00 miFair54°F42°F64%1017 hPa
Fort Meade / Tipton, MD18 mi72 minSE 610.00 miFair50°F41°F71%1016.9 hPa
Washington/Dulles International Airport, DC, VA19 mi77 minSSE 910.00 miMostly Cloudy57°F43°F60%1015.3 hPa
Fort Belvoir, VA19 mi73 minSE 510.00 miFair54°F42°F65%1016.2 hPa

Wind History from CGS (wind in knots)
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Last 24hrCalmCalmCalmS3S3CalmCalmCalmCalmCalmCalmCalmCalmSW5S4SW3SW4CalmS3S5
G15
S7SE4S4S3
1 day agoCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalm
2 days agoCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmS3S3SW5W7SW5SW6CalmCalmCalmCalmCalm

Tide / Current Tables for Chain Bridge, D.C.
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Chain Bridge
Click for Map
Mon -- 06:13 AM EST     -0.13 feet Low Tide
Mon -- 07:22 AM EST     Sunrise
Mon -- 10:31 AM EST     Moonrise
Mon -- 11:49 AM EST     2.65 feet High Tide
Mon -- 05:18 PM EST     Sunset
Mon -- 06:34 PM EST     -0.01 feet Low Tide
Mon -- 10:48 PM EST     Moonset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
2.62.31.71.10.50.1-0.1-0.10.31.122.52.62.41.91.30.70.3000.20.81.72.4

Tide / Current Tables for Chain Bridge, one mile below, Washington, D.C.
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Chain Bridge
Click for Map
Mon -- 06:08 AM EST     -0.18 feet Low Tide
Mon -- 07:22 AM EST     Sunrise
Mon -- 10:30 AM EST     Moonrise
Mon -- 11:46 AM EST     2.67 feet High Tide
Mon -- 05:18 PM EST     Sunset
Mon -- 06:28 PM EST     -0.06 feet Low Tide
Mon -- 10:48 PM EST     Moonset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
2.72.31.710.4-0-0.2-0.10.41.22.12.62.72.41.91.30.70.2-0-00.20.91.82.4

Weather Map and Satellite Images
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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 (21,6,7,8)
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Ground Weather Radar Station Sterling, VA
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weather_mapweather_map weather_map

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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.