Thursday, April25, 2019 L-36.com


Marine Weather and Tides
Indian Head, MD

Version 3.4
What's New / NOTES
10/6/2018 Colors of tide XTide graphs changed to emphasize that they were upgraded. See next note. Comments welcome.
10/4/2018 I have fixed XTide and updated the harmonic files. There were some name changes so you might have to click EDIT to find the new station name.

Sunrise 6:17AMSunset 7:56PM Thursday April 25, 2019 7:41 PM EDT (23:41 UTC) Moonrise 12:22AMMoonset 10:10AM Illumination 61% 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- 735 Pm Edt Thu Apr 25 2019
.small craft advisory in effect from Friday morning through late Friday night...
Tonight..SE winds 5 kt. Waves less than 1 ft. A chance of showers.
Fri..S winds 10 to 15 kt with gusts to 30 kt... Becoming sw with gusts to 25 kt late. Waves 1 to 2 ft. Showers and tstms.
Fri night..W winds 10 to 15 kt. Gusts up to 30 kt... Diminishing to 25 kt after midnight. Waves 1 ft. A chance of showers.
Sat..W winds 10 to 15 kt with gusts to 30 kt. Waves 1 ft.
Sat night..W winds 5 to 10 kt with gusts to 20 kt... Becoming E after midnight. Waves 1 ft.
Sun..S winds 5 kt...becoming W 10 to 15 kt with gusts to 25 kt in the afternoon. Waves 1 ft.
Sun night..N winds 10 to 15 kt. Gusts up to 25 kt in the evening. Waves 1 ft.
Mon..SE winds 5 kt. Waves less than 1 ft. A chance of showers through the night.
Tue..SW winds 5 kt. Waves less than 1 ft. A chance of showers. Winds and waves higher and visibilities lower in and near tstms.
ANZ500 735 Pm Edt Thu Apr 25 2019
Synopsis for the tidal potomac and md portion of the chesapeake bay.. A warm front will move north over the waters tonight. A cold front will cross from west to east Friday. A weak ridge of high pressure will move overhead late Saturday followed by another low pressure system on Sunday. Small craft advisories will be required Saturday, with gale warnings possible. Small craft advisories may be necessary again Sunday and Sunday night.


7 Day Forecast for Marine Location Near Indian Head, MD
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location: 38.62, -77.2     debug


Area Discussion for - Baltimore, MD/Washington
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Fxus61 klwx 251856
afdlwx
area forecast discussion
national weather service baltimore md washington dc
256 pm edt Thu apr 25 2019

Synopsis
A warm front will move north across virginia today and into
maryland tonight. Low pressure will track across the ohio
valley and eastern great lakes tonight into Friday, pulling a
cold front across the area Friday afternoon. High pressure will
build in behind this front for the early part of the weekend.

Another storm system could approach the region Sunday.

Near term through tonight
Frontal boundary is residing in southern virginia this
afternoon and will move northward across the region this evening
and tonight. Isolated to scattered showers sprinkles exist
across portions of the area this afternoon, but
coverage intensity has been minimal so far. As the front lifts
north later today and this evening, the surface low tracks
northeastward through the ohio valley, and the upper trough
approaches, showers should increase in coverage. Some
instability may develop and an isolated thunderstorm or two is
also possible, mainly across eastern WV and va.

Lows tonight will range from the mid 50s to low 60s.

Short term Friday through Saturday night
Surface low pressure will move northeastward through the eastern
great lakes during the day Friday with its attendant surface
cold front crossing the region during the afternoon and early
evening hours. Some showers and or elevated isolated
thunderstorms may be ongoing early Friday morning, with activity
waning during the late morning hours. This will allow for
temperatures to rise and some instability to develop. Latest
model guidance including 12z NAM and 12z href members indicate
that between 500 and 1000 j kg of SBCAPE is likely to develop
ahead of the frontal boundary. This combined with strong low to
mid level wind field and 40 knots or so of bulk shear will set
the stage for strong to locally severe thunderstorms, mainly
from the blue ridge mountains eastward, with the highest
probability of severe across portions of central va, eastward to
dc, and into southern maryland where a slight risk of severe
thunderstorms was introduced.

Showers thunderstorms will likely develop around noon or so
across eastern WV and central va, and move eastward across the
region, exiting east of the chesapeake bay by 7 pm. The highest
threat window for severe thunderstorms will likely exist between
2 pm and 6 pm. Several discrete cells are possible ahead of what
may become a more organized developing squall line. The primary
threat will be isolated damaging wind gusts, but given
low level directional shear and relatively high helicity values,
an isolated tornado is also possible, with the highest
probabilities in southern md.

Heavy rainfall will also occur with these showers thunderstorms,
and while a widespread flood event is not likely, an isolated
incident of flooding is possible if any training thunderstorms
occur.

Highs on Friday will range from the upper 60s to low 70s.

The front will then push eastward Friday night with strong
west-northwest flow following behind. Gusty winds are expected
with 30-40 mph likely, although mixing may be limited at night.

It's possible a wind advisory may be needed, especially across
the higher elevations, but uncertainty exists at this time. The
wind field begins to weaken Saturday but mixing will increase
during the daylight hours, so gusty winds may actually MAX out
Saturday morning. Highs Saturday in the 60s to around 70f.

A weak ridge of high pressure moves overhead Saturday evening
before shifting eastward and offshore by Sunday morning as a
weak area of low pressure approaches. Some showers become
possible Saturday night.Lows in the 40s to low 50s.

Long term Sunday through Thursday
A cold front will cross the area Sunday afternoon. Moisture and
instability will be limited with the best moisture and instability
focused to our region's north. Rainfall amounts will be light.

Dry weather is expected Sunday night as strong high pressure builds
in from the northwest.

Moisture returns Monday night as high pressure shifts east. A
developing front over the ohio valley will be the focus for showers
and thunderstorms. Although disturbances will move along the front,
the front will remain nearly stationary with very little shower or
thunderstorm activity initially. Expect unsettled weather to
redevelop toward the middle and latter part of the week with a
chance for thunderstorms.

Aviation 18z Thursday through Tuesday
PrimarilyVFR conditions expected through the period. Ceilings
will gradually lower and clouds will thicken this evening and
tonight. Showers and even a few isolated thunderstorms will
develop this evening and tonight. Brief reductions to MVFR are
possible, with the highest probabilities of more consistent MVFR
ceilings at mtn mrb.

A strong cold front will then cross the terminals Friday.

PredominantVFR anticipated, but local ifr possible within
showers storms. In addition, local gusty winds (40-50 kt)
possible in stronger storms. Placement of these cells
problematic this far out, but the general time frame for strong
winds wind shift will be mid afternoon mrb cho and late
afternoon at the hubs (iad dca bwi).

Gusty northwest winds will continue behind the front Friday
night into Saturday before diminishing Saturday night. Gusty
nw winds anticipated once again Sunday afternoon through Sunday
evening behind another frontal passage.

A few showers are also possible Monday night. Conditions could
briefly become MVFR in these showers.

Marine
Generally light winds expected on the waters through tonight.

Flow which is predominantly northerly this afternoon will
become south this evening and tonight as a warm front slowly
crosses the waters.

By Friday, a sharp cold front will be approaching the waters.

While mixing won't be ideal, there will be a healthy gradient
wind in advance of this front. A small craft advisory is in
effect beginning at 12 noon. The environment will also become
favorable for development of clustered showers thunderstorms
Friday afternoon capable of producing gusty winds in excess of
34 knots and possibly up to 50 knots, and special marine
warnings may become necessary.

In the wake of the cold front Friday night into Saturday the
gradient remains tight, with 30-35 kt (and depending upon model
solution, perhaps up to 40 kt) still available. Momentum
transfer will be more optimal. A SCA is in effect, but an
upgrade to gale may be needed. The strong winds will continue
into Saturday morning before gradually relaxing during the
afternoon hours.

Small craft advisory conditions expected Sunday and Sunday night
with frequent gusts to around 25 knots. Winds diminish below
criteria later Sunday night through Monday night.

Lwx watches warnings advisories
Dc... None.

Md... None.

Va... None.

Wv... None.

Marine... Small craft advisory from noon Friday to 6 am edt Saturday for
anz530>543.

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


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
WASD2 - 8594900 - Washington, DC 20 mi48 min ESE 5.1 G 8 73°F 65°F1010.7 hPa
NCDV2 22 mi48 min SE 8.9 G 9.9 69°F 69°F1009.8 hPa
SLIM2 - 8577330 - Solomons Island, MD 45 mi48 min E 6 G 8 65°F 64°F1010.6 hPa
TPLM2 - Thomas Point, MD 45 mi42 min E 9.9 G 9.9 66°F 64°F1012.1 hPa (+0.0)52°F
APAM2 - 8575512 - Annapolis, MD 46 mi48 min 67°F 1010.8 hPa
COVM2 - 8577018 - Cove Point LNG Pier, MD 46 mi48 min ESE 8.9 G 11 66°F 1011.8 hPa
PPTM2 - 8578240 - Piney Point, MD 49 mi48 min SSE 8.9 G 8.9

Wind History for Washington, DC
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Fort Belvoir, VA8 mi1.8 hrsN 010.00 miFair74°F52°F47%1010.8 hPa
Quantico Marine Corps Airfield - Turner Field, VA9 mi1.8 hrsN 010.00 miFair75°F52°F45%1010.7 hPa
Manassas, Manassas Regional Airport/Harry P. Davis Field, VA18 mi46 minSE 310.00 miFair71°F53°F53%1011.7 hPa
Washington/Reagan National Airport, DC, VA19 mi50 minESE 910.00 miMostly Cloudy72°F53°F52%1010.6 hPa
Stafford, Stafford Regional Airport, VA20 mi67 minE 710.00 miFair72°F54°F53%1011.8 hPa
Camp Springs / Andrews Air Force Base, MD23 mi1.8 hrsE 510.00 miPartly Cloudy71°F50°F48%1011.4 hPa

Wind History from DAA (wind in knots)
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Last 24hrSE3CalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmSE3E3CalmCalmSE3NE3E5SE5CalmE3
1 day agoS5Calm--CalmCalmCalmCalmCalmCalmCalmCalmCalmNW10N8N5NW10
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2 days agoNW5CalmCalmCalmCalmCalmCalmCalmSE3CalmCalmCalmCalmCalmSE3SE6S6S7S8S8S9S8S10S6

Tide / Current Tables for High Point, Occoquan Bay, Virginia
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High Point
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Thu -- 12:18 AM EDT     1.67 feet High Tide
Thu -- 01:21 AM EDT     Moonrise
Thu -- 06:19 AM EDT     Sunrise
Thu -- 06:25 AM EDT     0.29 feet Low Tide
Thu -- 11:10 AM EDT     Moonset
Thu -- 12:24 PM EDT     1.79 feet High Tide
Thu -- 07:19 PM EDT     0.25 feet Low Tide
Thu -- 07:54 PM EDT     Sunset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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1.71.61.410.70.40.30.30.50.91.41.61.81.81.51.20.90.60.40.30.30.611.3

Tide / Current Tables for Marshall Hall, Maryland
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Marshall Hall
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Thu -- 01:18 AM EDT     2.43 feet High Tide
Thu -- 01:21 AM EDT     Moonrise
Thu -- 06:18 AM EDT     Sunrise
Thu -- 07:03 AM EDT     0.41 feet Low Tide
Thu -- 11:09 AM EDT     Moonset
Thu -- 01:24 PM EDT     2.60 feet High Tide
Thu -- 07:54 PM EDT     Sunset
Thu -- 07:57 PM EDT     0.35 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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2.22.42.31.91.40.90.50.40.50.91.522.42.62.52.21.71.20.80.50.40.50.91.5

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 (19,4,5,8)
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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.