Thursday, June20, 2019 L-36.com


Marine Weather and Tides
Olney, MD

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Sunrise 5:40AMSunset 8:39PM Thursday June 20, 2019 7:38 PM EDT (23:38 UTC) Moonrise 10:22PMMoonset 7:36AM Illumination 88% Phase: Waning Gibbous; Moon at 18 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- 438 Pm Edt Thu Jun 20 2019
.small craft advisory in effect through Friday afternoon...
Rest of this afternoon..SW winds 10 kt with gusts to 20 kt. Waves 1 ft. Isolated showers and tstms.
Tonight..W winds 5 to 10 kt. Gusts up to 20 kt in the evening. Waves 1 ft. A chance of showers.
Fri..NW winds 10 to 15 kt with gusts to 25 kt. Waves 1 ft.
Fri night..NW winds 10 to 15 kt with gusts to 20 kt...diminishing to 5 kt after midnight. Waves 1 ft.
Sat..NW winds 5 to 10 kt. Waves 1 ft.
Sat night..NW winds around 5 kt. Waves 1 ft or less.
Sun..SW winds around 5 kt. Waves 1 ft.
Mon..SW winds around 5 kt. Waves 1 ft. A chance of showers. A chance of tstms through the night. Winds and waves higher and visibilities lower in and near tstms.
ANZ500 438 Pm Edt Thu Jun 20 2019
Synopsis for the tidal potomac and md portion of the chesapeake bay.. Low pressure tracking to the northwest will sweep a cold front through the area late this afternoon and tonight. High pressure nudging southward from canada will dominate over the waters through the weekend. A warm front will then cross the waters Monday.


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


Area Discussion for - Baltimore, MD/Washington
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Fxus61 klwx 201854
afdlwx
area forecast discussion
national weather service baltimore md washington dc
254 pm edt Thu jun 20 2019

Synopsis
Low pressure over ohio will push a cold front across the region
late this afternoon and evening. Behind the cold front,
canadian high pressure will build southward over the region
Friday and into the weekend. This high will begin retreating
northward on Sunday as a warm front lifts toward the region
Sunday night.

Near term through tonight
A band of strong thunderstorms, producing lightning and heavy
rain, is slowly exiting the northern extent of the chesapeake
bay. Behind it, scattered showers and thunderstorms are
developing and moving toward and across the city of baltimore
and nearby bwi airport. Very little activity extends farther
west. As a matter of fact, scattered light to moderate showers
are across the potomac highlands. Additional heavy showers and
strong to severe thunderstorms are expected to develop over the
next 4 hours or so, mainly across the virginia piedmont and
eastern portions of virginia toward the northern neck. There is
currently a severe thunderstorm watch in effect for orange and
spotsylvania counties in virginia. Thunderstorms that do develop
and move across these areas could produce damaging winds and
large hail. Temperatures across the region are in the middle
80s to near 90 with dewpoint temperatures in the upper 60s to
lower 70s. This type of warmth and moisture at the surface could
only fuel such thunderstorms.

Elsewhere, from the northern potomac highlands east to the
chesapeake bay, late this afternoon and evening, there shouldn't
be too much thunderstorm activity. A west-southwest to westerly
wind has developed recently and will linger into this evening.

This "down-sloping" wind would inhibit other activity as the
main surface cold front and upper level support push eastward.

Showers and thunderstorms will end and move east later this
evening as the front pushes east. Additional spotty showers
could linger as the upper level trough pivots across the area
overnight. Lows will fall into the 60s, with winds picking up
from the northwest late behind the front.

Short term Friday through Saturday night
Cooler and drier canadian high pressure will slowly build in
through the first half of the weekend as the cold front settles
to our south. Strong pressure gradient behind the surface low on
Friday may bring gusts of 30-40 mph. Otherwise, any early
showers should give way to sunshine and pleasant conditions.

Highs mainly in the low 80s.

Winds diminish Friday night into Saturday as high pressure
builds closer to the region and the gradient relaxes. The drier
air will allow temps to drop into the 50s in most of the region
Friday night, but sunshine should allow a rebound back to the
low 80s on Saturday. A few showers or a stray t-storm could
develop late in the day or at night in w-central va close to the
stalled front, but otherwise, dry weather should prevail
through the forecast area through Saturday night.

Long term Sunday through Thursday
Upper level ridging will build overhead as high pressure retreats
off to the east on Sunday. A warm front will be positioned off to
our southwest. A few showers or thunderstorms may be possible during
the afternoon hours in the vicinity of this front across
southwestern portions of our forecast area. Elsewhere conditions are
expected to remain dry, with mostly sunny skies. High temperatures
will reach into the low-mid 80s with dewpoints in the upper 50s to
around 60.

The aforementioned warm front will push through by Monday, bringing
in a warm and humid airmass. High temperatures will push 90 degrees
each day Monday through Wednesday, with dewpoints climbing back into
the upper 60s to near 70. The main synoptic scale feature of
interest Monday through Wednesday will be a trough which is progged
to track from the central plains toward the great lakes. Exactly
where this feature tracks will have an impact on the coverage of
showers and thunderstorms we see during the Monday through Wednesday
time period. As it stands now, there will be at least a low end
chance for showers and thunderstorms each day with the warm and
humid airmass in place. However, there could be more focused periods
of thunderstorm activity. The finer scale details will become
clearer once there's better agreement with respect to the exact
track and timing of the aforementioned trough.

Aviation 19z Thursday through Tuesday
A brief period of 5 to 10 minutes of ifr conditions expected
near mtn and bwi as a band of thunderstorms move across the
northern chesapeake bay and northeast maryland. Otherwise, cho
terminal could get a gusty thunderstorm late this afternoon,
while iad could get a heavy shower.VFR conditions outside of
this convection.

Winds become northwest and may gust up to 35 knots late tonight
through Friday behind the cold front, but otherwise,VFR
conditons should prevail. Winds diminish Friday night and
Saturday as high pressure builds in, with conditions otherwise
remainingVFR.

PrimarilyVFR conditions are expected across the area through
Wednesday. However, brief reductions to sub-vfr conditions will be
possible in association with any thunderstorms that move over the
terminals.

Marine
Winds are approaching or have reached SCA in the central
chesapeake bay this morning and will continue to increase this
afternoon as southerly fetch ahead of an approaching cold front
increases. Thus, have raised SCA for most of the waters by this
afternoon into the evening. Remaining waters may still need one
but confidence is not high in the far north yet.

Later tonight and through Friday into Friday night, strong
northwest winds behind the cold front will bring SCA to all
waters, which is also now in effect. Some places could even
flirt with low end gale, a rarity with a synoptic system in late
june. Winds should relax by Saturday as high pressure builds
back in.

Sub-sca level winds are expected on both Sunday and Monday. A few
thunderstorms can't be ruled out over the waters on Sunday or
Monday.

Lwx watches warnings advisories
Dc... Coastal flood advisory until 4 pm edt this afternoon for
dcz001.

Md... None.

Va... None.

Wv... None.

Marine... Small craft advisory until 6 pm edt Friday for anz532>537-
539>543.

Small craft advisory from midnight tonight to 6 pm edt Friday
for anz530-531-538.

Synopsis... Klw
near term... Klw
short term... Klw
long term... Kjp
aviation... Klw kjp
marine... Klw kjp


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
WASD2 - 8594900 - Washington, DC 19 mi57 min NW 7 G 17 87°F 80°F999.3 hPa
BLTM2 - 8574680 - Baltimore, MD 27 mi57 min N 9.9 G 14 86°F 80°F998.7 hPa
FSKM2 - 8574728 - Francis Scott Key Bridge, MD 29 mi51 min NW 13 G 16 84°F 998.9 hPa
FSNM2 29 mi63 min WNW 18 G 21 85°F 999 hPa
APAM2 - 8575512 - Annapolis, MD 33 mi51 min 80°F 998.3 hPa
44063 - Annapolis 35 mi33 min SSW 1.9 G 5.8 77°F 77°F998.9 hPa
CPVM2 38 mi57 min 78°F 78°F
TPLM2 - Thomas Point, MD 38 mi39 min W 1.9 G 2.9 81°F 76°F999.7 hPa (-0.5)65°F
TCBM2 - 8573364 - Tolchester Beach, MD 44 mi57 min WNW 9.9 G 12 83°F 78°F999.1 hPa

Wind History for Washington, DC
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Gaithersburg - Montgomery County Airport, MD5 mi43 minWNW 510.00 miMostly Cloudy82°F68°F63%1001.3 hPa
College Park Airport, MD14 mi56 minNNW 310.00 miPartly Cloudy84°F66°F55%999 hPa
Fort Meade / Tipton, MD16 mi57 minNW 510.00 miPartly Cloudy81°F68°F66%1000 hPa
Washington/Reagan National Airport, DC, VA20 mi47 minWNW 810.00 miLight Rain87°F66°F51%999.4 hPa
Baltimore, Baltimore-Washington International Airport, MD21 mi45 minNW 8 G 1710.00 miMostly Cloudy84°F64°F53%998.9 hPa
Washington/Dulles International Airport, DC, VA24 mi47 minWSW 610.00 miMostly Cloudy82°F64°F56%999.8 hPa

Wind History from GAI (wind in knots)
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Last 24hr3CalmCalmSE43S5S34S4SW3CalmS4S3SW3S44SW9W10W10W9
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1 day agoS6S4S3S4CalmSE5SE6S4CalmSW4CalmCalmCalmSE3SE4SE44SE7S4SW55SW5SE7S7
2 days agoNE3CalmS4CalmSE3S4CalmCalmCalmCalmSE3SE3SE3CalmCalmW54W9W6W9W8W11W7NW4

Tide / Current Tables for Chain Bridge, D.C.
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Chain Bridge
Click for Map
Thu -- 05:42 AM EDT     Sunrise
Thu -- 05:45 AM EDT     0.43 feet Low Tide
Thu -- 08:36 AM EDT     Moonset
Thu -- 11:29 AM EDT     3.34 feet High Tide
Thu -- 06:32 PM EDT     0.29 feet Low Tide
Thu -- 08:37 PM EDT     Sunset
Thu -- 11:21 PM EDT     Moonrise
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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2.92.51.91.30.80.50.40.81.52.433.33.32.92.31.71.10.70.40.30.81.62.32.8

Tide / Current Tables for Chain Bridge, one mile below, D.C.
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Chain Bridge
Click for Map
Thu -- 05:40 AM EDT     0.43 feet Low Tide
Thu -- 05:42 AM EDT     Sunrise
Thu -- 08:36 AM EDT     Moonset
Thu -- 11:24 AM EDT     3.34 feet High Tide
Thu -- 06:27 PM EDT     0.29 feet Low Tide
Thu -- 08:36 PM EDT     Sunset
Thu -- 11:21 PM EDT     Moonrise
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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2.92.41.81.20.80.50.40.81.62.433.33.32.82.21.61.10.60.30.40.81.62.32.8

Weather Map and Satellite Images
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GOES Local Image of    EDIT
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Wind Forecast for Baltimore, MD/Washington (19,4,5,8)
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Ground Weather Radar Station Sterling, VA
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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.