Wednesday, August23, 2017 L-36.com


Marine Weather and Tides
Cobb Island, 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 6:28AMSunset 7:51PM Wednesday August 23, 2017 4:20 AM EDT (08:20 UTC) Moonrise 7:22AMMoonset 8:10PM Illumination 1% Phase: Waxing Crescent; Moon at 1 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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ANZ537 Tidal Potomac From Cobb Island To Smith Point- 258 Am Edt Wed Aug 23 2017
.small craft advisory in effect until 5 am edt early this morning...
Overnight..SW winds 20 kt...diminishing to 10 kt late. Waves 2 ft. A slight chance of showers.
Wed..NW winds 5 to 10 kt. Waves 1 ft. A chance of showers.
Wed night..N winds 5 to 10 kt. Waves 1 ft. A chance of showers.
Thu..N winds 5 to 10 kt. Waves 2 ft.
Thu night..NW winds around 5 kt. Waves 1 ft.
Fri..N winds around 5 kt. Waves 1 ft.
Fri night..NE winds 5 to 10 kt. Waves 1 ft.
Sat..NE winds 5 to 10 kt. Waves 1 ft.
Sun..NE winds 5 to 10 kt. Waves 1 ft.
ANZ500 258 Am Edt Wed Aug 23 2017
Synopsis for the tidal potomac and md portion of the chesapeake bay.. A cold front will cross the waters late tonight into early Wednesday. High pressure will return for the second half of the week.

7 Day Forecast for Marine Location Near Cobb Island, MD
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location: 38.22, -76.75     debug


Area Discussion for - Wakefield, VA
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Fxus61 kakq 230756
afdakq
area forecast discussion
national weather service wakefield va
356 am edt Wed aug 23 2017

Synopsis
High pressure remains centered off the mid atlantic coast
through tonight as a cold front begins to approach from the
west. The front crosses the area late Wednesday afternoon
through Wednesday night, with strong high pressure building
north of the area from Thursday into the upcoming weekend.

Near term until 6 pm this evening
No major changes necessary to the previous forecast. Still
expecting a dry night aside from a stray shower late over
northern areas.

Previous discussion...

warm humid tonight with little chance for any rain under a sw
wind of 10 mph. Lows mainly in the mid to upper 70s. Clouds
increase across the north ahead of the approaching cold front
and lead shortwave. Have introduced a slight chance pop for the
maryland eastern shore late tonight, but best chances for
measurable precipitation remain north and west of the local
area.

Short term 6 pm this evening through Friday
Models in good agreement with dropping the cold front into the
local area Wednesday morning, then pushing the front across the
area through Wednesday afternoon. Shearing vort lobe progged to
ride along the front as winds increase aloft. The added forcing
along the boundary along a narrow ribbon of high precipitable
waters will result in scattered to numerous showers and
thunderstorms Wednesday afternoon. Downslope flow from 1-3km
will limit the coverage over the piedmont, but hi-res and course
resolution guidance indicates that the activity should become
more organized central virginia eastward as it interacts a
moderately unstable air mass (mixed-layer CAPE values 500-1500
j kg) and marginal shear (25-30 knots). Dry mid levels and an
inverted v sounding indicate the main threat will be damaging
winds and frequent lightning. SPC maintains a marginal risk for
severe weather across the southeast half of the local area.

Heavy rainfall is also possible as the cold front slows as it
reaches southeast virginia and northeast north carolina
Wednesday afternoon. Precipitable water values progged around 2
to 2.25 inches. Westerly flow in the mid levels indicates that
the motion should prevent widespread heavy rainfall, but some
areas could see periods of heavy rainfall. No headlines planned
at this time. Flow becomes north to northeast behind the front,
as dry air spreads into the area from the northwest. The front
and upper wave push offshore Wednesday evening. Guidance
indicates a wave of low pressure develops along the front over
the carolinas, keeping rain chances in northeast north carolina
and far southeast virginia through Wednesday night. Highs
Wednesday range from the mid 80's northwest to around 90
southeast. Lows Wednesday night in the low to mid 60's inland to
the low 70's near the coast.

High pressure builds in from the northwest Thursday as the front
stalls along the southeast coast. Will keep low chance pops
across northeast north carolina Thursday nearest the front and
deepest moisture. Otherwise, dry, cooler and less humid
conditions expected. Highs Thursday forecast in the low to mid
80's under a partly cloudy sky.

Long term Friday night through Tuesday
Cooler and drier for the late week period courtesy of building
longwave upper level trough over the eastern united states.

Meanwhile, broad 1024+ mb surface high pressure builds south over
the interior northeast from great lakes Thursday and Friday,
eventually setting up over new england and ridging down the east
coast over the weekend into early next week. Forecast remains mostly
dry, although a few showers possible along the coast in persistent
onshore flow.

Medium range guidance in relatively good agreement with developing a
tropical system along and offshore of the southeast coast along the
old frontal boundary early next week. Kept weekend dry, with low
rain chances along the SE coast by Monday. Looking ahead, rain
chances look to improve into the middle of next week, with moisture
from the remnants of harvey looming to the sw. For temperatures,
high temperatures fri-mon will be at or just slightly below normal
through the period, mainly in the upper 70s to low 80s. Early
morning lows in the 50s inland to mid 60s along the coast.

Aviation 08z Wednesday through Sunday
Early this morning, a cold front was moving into NRN nw
portions of the cwa. That front will slowly push SE acrs the
region and off the coast today into Thu morning. Flight
restrictions will be possible along and behind the front this
aftn into Thu morning fm showers and tstms. The front should
push SE of NE nc during thu, with lingering showers possible
over extrm SE va NE nc. Conditions are expected to improve
thu aftn thru fri, as the front shifts farther SE and high
pressure builds north of the region. Breezy NE winds expected
near the coast Thu and fri.

Marine
A cold front will approach the waters from the northwest and
cross the area late this aftn through tonight. SW flow still
avearges 15-20 kt over the bay and coastal waters, have the sca
headlines through 7 am for the entire bay and for the NRN coatl
waters. Waves avg 2 to 3 feet in the bay and seas acrs the N are
4-5 ft. Winds shift to the N NE 10 to 15 knots behind the front
by late this morning N and by aftn farther S (and with
convection this aftn winds will be locally much stronger but
this will be handled W mws smw's as needed).

Strong high pressure builds north of the region Thursday and
into the weekend. Given the warm waters and some cold advection
late tonight Thu morning, expect a marginal SCA event over at
least some of the bay and probably the lower james Thu morning.

Did not raise any SCA headlines as this will be mainly a 3rd
period event (and still fairly marginal). Otherwise expect
diminishing winds later Thu aftn through Fri as sfc high
pressure builds a little farther south and the pressure gradient
weakens. Waves in the lower bay may briefly build to 3-4 ft thu
morning, then will subside to 1-2 ft with coastal seas 3-4 ft.

Onshore (e-ne) flow for the weekend as high pressure builds nnw
of the local area and then shifts east to new england. Winds
remain elevated 10 to 15, occasional gusts to ~20 kt sat, and
then increase more significantly Sunday into next week as
stalled front to the south lifts back N with low pressure
developing along the boundary. Seas remain choppy sat, and then
will build to 5-7 ft or greater late Sun into next week.

Akq watches warnings advisories
Md... None.

Nc... None.

Va... None.

Marine... Small craft advisory until 7 am edt this morning for
anz630>632-634-650-652.

Synopsis... Tmg
near term... Tmg
short term... Lkb sam tmg
long term... Mam
aviation... Tmg
marine... Lkb


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
PPTM2 - 8578240 - Piney Point, MD 13 mi51 min WSW 8 G 11
NCDV2 17 mi51 min NW 1 G 2.9 80°F 83°F1008.6 hPa
SLIM2 - 8577330 - Solomons Island, MD 17 mi51 min NW 5.1 G 7 81°F 82°F
LWTV2 - 8635750 - Lewisetta, VA 22 mi51 min WSW 9.9 G 12 80°F 82°F1009.2 hPa
COVM2 - 8577018 - Cove Point LNG Pier, MD 23 mi51 min NW 8 G 8.9 80°F 1010 hPa
44042 - Potomac, MD 26 mi41 min SW 14 G 18 81°F 1008.3 hPa
44062 - Gooses Reef, MD 29 mi41 min WSW 5.8 G 9.7 82°F 1009.8 hPa
BISM2 - 8571421 - Bishops Head, MD 38 mi51 min SW 17 G 20 82°F 82°F1009.1 hPa
BSLM2 - Chesapeake Bay, MD 39 mi111 min Calm 76°F 1009 hPa72°F
CA2 - 8571892 - Cambridge, MD 44 mi51 min 80°F 83°F1010.1 hPa
WASD2 - 8594900 - Washington, DC 47 mi51 min WNW 1.9 G 2.9 80°F 83°F1009 hPa

Wind History for Piney Point, MD
(wind in knots)    EDIT      (on/off)   Help
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NE4
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
St Marys County Airport, MD12 mi44 minW 510.00 miFair77°F71°F83%1010.2 hPa
St. Inigoes, Webster Field, Naval Electronic Systems Engineering Activity, MD18 mi28 minWSW 810.00 miFair80°F75°F85%1008.9 hPa
Patuxent River, Naval Air Station, MD19 mi29 minWNW 410.00 miFair78°F75°F90%1009.2 hPa

Wind History from NUI (wind in knots)
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Last 24hrSW8SW6S5S7S5S6S9S7S11S9S9S10S7
G16
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G15
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1 day agoCalmCalmE4CalmSE5SE7SE5SE8S9SE7SE5SE10SE7SE8SE5SE4S4S5S5S5S5S6S9S9
2 days agoCalmCalm3NE4CalmN7N44W65NE4E3NE3NE4E3CalmCalmCalmCalmNE3CalmNE3CalmCalm

Tide / Current Tables for Colton's Point, Potomac River, Maryland
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Colton's Point
Click for Map
Wed -- 04:17 AM EDT     2.30 feet High Tide
Wed -- 06:28 AM EDT     Sunrise
Wed -- 08:21 AM EDT     Moonrise
Wed -- 10:22 AM EDT     -0.02 feet Low Tide
Wed -- 04:44 PM EDT     2.23 feet High Tide
Wed -- 07:49 PM EDT     Sunset
Wed -- 09:10 PM EDT     Moonset
Wed -- 10:43 PM EDT     0.06 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
0.71.21.82.12.32.21.81.20.70.3000.40.91.51.92.22.21.91.40.90.50.20.1

Tide / Current Tables for Point Patience, 0.1 mile southwest of, Maryland Current
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Point Patience
Click for MapFlood direction 315 true
Ebb direction 145 true

Wed -- 12:38 AM EDT     0.62 knots Max Flood
Wed -- 03:14 AM EDT     -0.00 knots Slack
Wed -- 06:27 AM EDT     Sunrise
Wed -- 07:10 AM EDT     -1.05 knots Max Ebb
Wed -- 08:20 AM EDT     Moonrise
Wed -- 11:18 AM EDT     0.00 knots Slack
Wed -- 01:14 PM EDT     0.56 knots Max Flood
Wed -- 03:46 PM EDT     -0.00 knots Slack
Wed -- 07:30 PM EDT     -0.87 knots Max Ebb
Wed -- 07:48 PM EDT     Sunset
Wed -- 09:09 PM EDT     Moonset
Wed -- 11:24 PM EDT     0.00 knots Slack
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
0.60.60.40.1-0.3-0.7-0.9-1.1-1-0.8-0.5-0.10.30.50.50.3-0.1-0.4-0.7-0.8-0.9-0.7-0.5-0.1

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 Wakefield, VA (4,6,7,8)
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Ground Weather Radar Station Dover AFB, DE
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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.