Wednesday, August21, 2019 L-36.com


Marine Weather and Tides
Silver Spring, MD

Version 3.4
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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 6:25AMSunset 7:56PM Wednesday August 21, 2019 7:10 AM EDT (11:10 UTC) Moonrise 10:15PMMoonset 10:58AM Illumination 67% Phase: Waning Gibbous; Moon at 21 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- 435 Am Edt Wed Aug 21 2019
.small craft advisory in effect from 1 pm edt this afternoon through this evening...
Rest of the overnight..S winds 5 kt. Waves less than 1 ft. Isolated showers and tstms.
Today..S winds 5 to 10 kt. Gusts up to 20 kt in the late morning and afternoon. Waves 1 ft. Scattered showers and tstms.
Tonight..SW winds 5 to 10 kt. Waves 1 ft. Scattered showers and tstms.
Thu..W winds 5 kt. Waves less than 1 ft. A chance of showers and tstms.
Thu night..NW winds around 5 kt. Waves 1 ft. A chance of showers.
Fri..N winds 5 kt. Waves less than 1 ft. A chance of showers and tstms.
Fri night..N winds 5 kt. Waves less than 1 ft. A chance of showers.
Sat..NE winds around 5 kt. Waves 1 ft. A chance of showers in the morning.
Sun..E winds 5 kt. Waves less than 1 ft. Winds and waves higher and visibilities lower in and near tstms.
ANZ500 435 Am Edt Wed Aug 21 2019
Synopsis for the tidal potomac and md portion of the chesapeake bay.. High pressure in the atlantic will promote a light southerly flow over the region today. A cold front will approach the waters late tonight into Thursday, before stalling near or south of the area into Friday. High pressure will then settle over the area Saturday into Sunday.


7 Day Forecast for Marine Location Near Silver Spring, MD
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location: 39, -77     debug


Area Discussion for - Baltimore, MD/Washington
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Fxus61 klwx 210800
afdlwx
area forecast discussion
national weather service baltimore md washington dc
400 am edt Wed aug 21 2019

Synopsis
An upper level disturbance will cross the region this afternoon
and evening. A cold front will approach the ohio valley
Wednesday, sinking into our area Wednesday night into Thursday,
possibly stalling into Friday. Behind the front, high pressure
will build over the region for the weekend.

Near term through tonight
A warm front is depicted across pennsylvania early this morning
as an area of low pressure is situated over the great lakes.

Over our area, skies are party to mostly cloudy as cloud debris
from decaying showers storms to our west and east drift
overhead. Temperatures are a touch cooler than we've seen the
past few nights, ranging from the middle 60s to lower 70s.

Dewpoints once again are on a similar track, so patchy fog is
being observed in the sheltered valleys along and west of the
blue ridge mountains.

The aforementioned low will track north and east of the great
lakes today, lifting the warm front into new england while at
the same time dragging a cold front toward the ohio valley late
in the day. As the upper level trough nearing west virginia this
morning slides eastward today, this will help trigger scattered
showers and thunderstorms this afternoon and evening.

Instability will not be as impressive as what we saw on Tuesday,
given a bit more cloud cover and slightly cooler temperatures,
and the best synoptic lift will reside north and east of the
mason dixon line. That being said, 1000-1500 j kg of mucape
should develop by this afternoon, along with modest low level
lapse rates and 0-6km shear coming in around 20-25 knots. Pwats
will remain elevated, hovering around two inches today. These
ingredients will support at least an isolated threat for severe
thunderstorms today, with damaging winds and large hail
continuing to be the primary threats.

Shower and thunderstorm activity this evening will dwindle, with
partly cloudy skies and mainly dry conditions persisting
overnight. Patchy fog will be possible towards morning as
temperatures bottom out in the middle 60s to middle 70s.

Short term Thursday through Friday night
The cold front will slowly drift into our area Thursday
morning, helping spark scattered showers and thunderstorms
during the afternoon and evening hours once again. Given the
front will be gracing us with its presence, while coinciding
with shortwave energy tracking overhead, do expect better
coverage of showers storms compared to today. Again, instability
may be limited given cloud cover and lower temperatures,
however we will remain moist and the flow will be parallel to
the front. So in addition to isolated strong to severe storms,
heavy rain resulting in isolated incidents of flooding will be a
concern.

The front shifts southward Thursday night into Friday, but
likely lingers close enough nearby to bring additional
scattered showers and storms on Friday afternoon and evening,
favoring our southern zones. Temperatures noticeably cooler on
Friday, likely holding in the 80s area wide. A drying trend
should commence Friday night as the front sinks further south
into southern virginia.

Long term Saturday through Tuesday
High pressure will build into the region from the north Saturday
and Sunday. Temperatures will be about 5 to 7 degrees below
average. Dry conditions and lower humidity is expected through the
period.

The high will move to the northeast Monday and Tuesday. This will
allow for a return southeast to southerly flow to bring the
humidity levels up and a chance of showers or a thunderstorms. The
discrepancy remains between the european models and GFS models as to
how many and how far north will showers and thunderstorms develop.

The european model keeps most, if not all, of our CWA dry through
Tuesday. The GFS model brings an upper level disturbance across our
region late Monday into Tuesday; thus, the chance for showers and
thunderstorms could be higher and farther north. Temperatures will
remain a few degrees below average, but humidity levels will rise
some.

Aviation 08z Wednesday through Sunday
Afternoon evening showers and storms can be expected through
Friday as a cold front slowly transits the area, bringing
periods of subVFR conditions. Patchy fog could also yield
MVFR ifr vis, mostly likely at mrb cho.

Vfr conditions for all terminals Saturday and Sunday. We can't
rule out a shower or thunderstorm near cho late Sunday into
Sunday night, which could briefly reduce conditions to MVFR.

Winds northeast around 5 knots Saturday and Saturday night. Winds
becoming easterly 5 to 10 knots Sunday.

Marine
Sca conditions expected over the waters today as the gradient
increases and a cold front nears the ohio valley. The gradient
is expected to relax overnight and remain below SCA criteria
Thursday and Friday. The front will drift over the waters on
Thursday, lingering nearby into Friday. As such, afternoon and
evening showers storms can be expected, some of which will
deliver strong gusty winds.

No marine hazards expected Saturday and Sunday. Winds northeast
around 5 knots Saturday and Saturday night. Winds becoming easterly
around 10 knots Sunday into Sunday evening.

Lwx watches warnings advisories
Dc... None.

Md... None.

Va... None.

Wv... None.

Marine... Small craft advisory from 1 pm this afternoon to 7 pm edt this
evening for anz530-531-535-536-538-539-542.

Small craft advisory from 9 am this morning to midnight edt
tonight for anz532>534-537-540-541-543.

Synopsis... Bkf
near term... Bkf
short term... Bkf
long term... Klw
aviation... Bkf klw
marine... Bkf klw


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
WASD2 - 8594900 - Washington, DC 9 mi58 min SW 5.1 G 8 74°F 85°F1015.2 hPa
BSLM2 - Chesapeake Bay, MD 22 mi100 min Calm 70°F 1015 hPa69°F
APAM2 - 8575512 - Annapolis, MD 28 mi52 min 74°F 1014.7 hPa
BLTM2 - 8574680 - Baltimore, MD 29 mi58 min SSW 1.9 G 2.9 73°F 84°F1014.6 hPa
FSKM2 - 8574728 - Francis Scott Key Bridge, MD 29 mi58 min S 4.1 G 6 73°F 1015 hPa
FSNM2 29 mi64 min S 2.9 G 5.1 73°F 1015 hPa
TPLM2 - Thomas Point, MD 31 mi70 min SSW 4.1 G 5.1 75°F 83°F1016.1 hPa (-0.7)72°F
CPVM2 32 mi58 min 76°F 74°F
TCBM2 - 8573364 - Tolchester Beach, MD 43 mi58 min SE 1.9 G 2.9 74°F 85°F1015.4 hPa
44062 - Gooses Reef, MD 44 mi34 min SSW 9.7 G 12 77°F 1016.4 hPa
NCDV2 47 mi58 min S 5.1 G 6 73°F 87°F1014.6 hPa

Wind History for Washington, DC
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
College Park Airport, MD4 mi27 minN 05.00 miFair0°F0°F%1015.2 hPa
Washington/Reagan National Airport, DC, VA10 mi18 minSSW 610.00 miMostly Cloudy73°F68°F84%1015.5 hPa
Camp Springs / Andrews Air Force Base, MD14 mi14 minSW 610.00 miFair71°F69°F95%1016 hPa
Fort Meade / Tipton, MD14 mi28 minN 07.00 miFair64°F64°F100%1016.3 hPa
Gaithersburg - Montgomery County Airport, MD15 mi14 minSSW 310.00 miFair71°F68°F90%1016.9 hPa
Fort Belvoir, VA21 mi14 minN 010.00 miPartly Cloudy69°F68°F96%1015.8 hPa
Baltimore, Baltimore-Washington International Airport, MD22 mi16 minN 010.00 miMostly Cloudy71°F69°F94%1015 hPa
Washington/Dulles International Airport, DC, VA24 mi18 minS 510.00 miMostly Cloudy70°F66°F90%1015.1 hPa

Link to 5 minute data for KCGS

Wind History from CGS (wind in knots)
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Last 24hrCalmCalmCalmNE3E5E7E5CalmSE5E7S3CalmCalmCalmCalm------CalmCalmCalm--CalmCalm
1 day agoCalmCalmCalmW3CalmCalmCalmW4W7NW4NW3N5CalmCalmSE6CalmCalm--------CalmCalmCalm
2 days agoCalmCalmCalmCalmSE3CalmCalmE5S8
G14
S8S4SE5SE5CalmCalmNW10
G18
Calm--CalmCalmCalm--CalmCalm

Tide / Current Tables for Benning Bridge, D.C.
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Benning Bridge
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Wed -- 12:38 AM EDT     3.31 feet High Tide
Wed -- 06:26 AM EDT     Sunrise
Wed -- 07:21 AM EDT     0.71 feet Low Tide
Wed -- 11:58 AM EDT     Moonset
Wed -- 12:58 PM EDT     3.07 feet High Tide
Wed -- 07:17 PM EDT     0.44 feet Low Tide
Wed -- 07:54 PM EDT     Sunset
Wed -- 11:14 PM EDT     Moonrise
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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3.23.332.51.91.30.90.70.811.72.42.93.12.92.51.81.20.70.50.50.81.52.3

Tide / Current Tables for Chain Bridge, D.C.
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Chain Bridge
Click for Map
Wed -- 12:41 AM EDT     3.19 feet High Tide
Wed -- 06:27 AM EDT     Sunrise
Wed -- 07:27 AM EDT     0.67 feet Low Tide
Wed -- 11:58 AM EDT     Moonset
Wed -- 01:02 PM EDT     2.96 feet High Tide
Wed -- 07:23 PM EDT     0.42 feet Low Tide
Wed -- 07:55 PM EDT     Sunset
Wed -- 11:14 PM EDT     Moonrise
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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3.13.22.92.41.91.30.90.70.711.62.32.832.82.41.81.20.70.40.50.71.32.2

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.
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Wind Forecast for Baltimore, MD/Washington (7,2,3,4)
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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.