Wednesday, May22, 2019 L-36.com


Marine Weather and Tides
Ravensworth, VA

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 5:49AMSunset 8:21PM Wednesday May 22, 2019 8:38 PM EDT (00:38 UTC) Moonrise 11:03PMMoonset 7:58AM Illumination 84% Phase: Waning Gibbous; Moon at 19 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- 736 Pm Edt Wed May 22 2019
.small craft advisory in effect from Thursday afternoon through Thursday evening...
Tonight..S winds 5 kt. Waves less than 1 ft. A slight chance of showers after midnight.
Thu..SW winds 5 to 10 kt with gusts to 20 kt. Waves 1 ft. A chance of showers and tstms.
Thu night..W winds 5 to 10 kt. Gusts up to 20 kt in the evening. Waves 1 ft. A chance of showers and tstms.
Fri..NW winds 10 to 15 kt with gusts to 20 kt. Waves 1 ft.
Fri night..NE winds 5 to 10 kt. Waves 1 ft.
Sat..SE winds 5 kt. Waves less than 1 ft.
Sat night..S winds 5 kt. Waves less than 1 ft.
Sun..NW winds 5 kt. Waves less than 1 ft. A chance of showers through the night.
Mon..NW winds 5 kt. Waves less than 1 ft. A chance of showers in the morning. Winds and waves higher and visibilities lower in and near tstms.
ANZ500 736 Pm Edt Wed May 22 2019
Synopsis for the tidal potomac and md portion of the chesapeake bay.. High pressure will move offshore through tonight. A warm front will approach the waters late tonight before passing through Thursday and a cold front will pass through the waters Thursday night. The cold front will stall out nearby for the rest of the weekend into early next week. A small craft advisory will be needed for the waters Friday, and possibly into Friday night.


7 Day Forecast for Marine Location Near Ravensworth, VA
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location: 38.82, -77.22     debug


Area Discussion for - Baltimore, MD/Washington
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Fxus61 klwx 221829
afdlwx
area forecast discussion
national weather service baltimore md washington dc
229 pm edt Wed may 22 2019

Synopsis
High pressure will move offshore through this evening. A warm
front will pass through the area late tonight into Thursday. A
cold front will approach Thursday night before stalling out
nearby for Friday and Saturday. The boundary will likely
dissipate Sunday but another cold front will approach from the
north and this boundary will likely stall out nearby for the
early portion of next week. Unsettled conditions are possible
during this time.

Near term through tonight
High clouds associated with the right entrance of a departing
jetmax will gradually thin out this afternoon and evening,
allowing for partly to mostly sunny skies. MAX temps will top
off in the mid to upper 70s for most locations.

A warm front will move into the region late tonight along with a
weak upper-level disturbance. There may be just enough lift
ahead of the boundary to trigger a few showers and perhaps even
a thunderstorm. However, coverage should be isolated to
scattered since the lifting mechanism will be weak and
instability will be elevated and limited. No severe weather is
expected. Min temps will hold in the upper 50s to the
lower middle 60s for most areas due to the southerly winds.

Short term Thursday through Friday night
The warm front will pass through the area Thursday morning. A
couple showers and perhaps even an isolated thunderstorm may
accompany the frontal passage, but again coverage will be
isolated to widely scattered.

A west to southwest flow behind the boundary will usher in
noticeably warmer and more humid conditions. MAX temps will top
off well into the 80s for most areas, and a few locations may
even approach 90 degrees. Dewpoints should rise into the 60s for
most areas, making it feel more uncomfortable as well.

Still keeping a close eye on the potential for severe
thunderstorms Thursday afternoon and evening. The warmer and
more humid conditions will lead to an unstable atmosphere. The
12z href forecasts mean SBCAPE to be about 1-2kj kg across most
of the area with locally higher amounts east of the blue ridge
mountains (where dewpoints will be a bit higher east of a
pressure trough). Deep layer shear will most likely be around 40
to 50 knots, which is plenty to support the threat of severe
thunderstorms. Latest guidance has come into better agreement
that an MCS will track across the midwest tonight and then
toward our area Thursday morning. The system will likely pass
through our area Thursday afternoon and evening, and with the
moderate instability and shear in place... The threat for severe
thunderstorms is elevated with damaging winds being the
primary threat along with large hail. Confidence is still low on
exactly how this will play out because it will be highly
dependent on the strength of the mcs, which has not developed
yet. If the MCS holds together and tracks through our area, then
the threat for severe thunderstorms will be enhanced. However,
if the MCS dissipates before reaching our area, then popup
thunderstorms will still pose a threat for severe weather but it
will be more isolated. Latest thinking is that the best chance
for more enhanced severe weather will be across our northern and
perhaps even central areas... Where height falls are more
noticeable and there will be less of an impact from downsloping
low-level westerly flow.

The actual cold front will drop into our area from the north
Thursday night. Convection will dissipate overnight with the
loss of daytime heating and a downslope west to northwest flow.

The cold front will stall out over central virginia. There will
not be much of a temperature gradient with MAX temps ranging
from the lower to middle 80s for most areas, but upper 80s to
near 90 in central virginia. Dewpoints will mix down into the
50s north of the boundary making it more comfortable compared to
Thursday. High pressure will briefly build overhead Friday
night, allowing for dry conditions. The boundary will likely
push farther south and west likely getting hung up near
appalachains.

Long term Saturday through Wednesday
Mid-upper level flow will be zonal across the eastern conus
through the extended forecast period. Consequently,
latitudinal variability in frontal positions will be
constrained. Low pressure will be tracking across canada this
weekend, which will drop a cold front across the great lakes
toward new england. This front likely will stall; it remains to
be seen whether that will be across the forecast area, to the
north, or to the south. Regardless, we'll be close enough to the
frontal zone for a chance of showers (and some thunderstorms)
on most days. Sunday may become the most pronounced of those
days, as that will be when frontal forcing collides with a
warmer, more humid air mass. Ultimately, forecast temperatures
will depend upon resolving fate of that boundary, and it appears
that there may be an opportunity for it to be south of the area
for at least one day.

Aviation 17z Wednesday through Sunday
Vfr conditions are expected most of the time through Friday
night. An isolated shower or thunderstorm may impact the
terminals late tonight into Thursday morning, but severe storms
are not expected. There is a better chance for thunderstorms
Thursday afternoon and evening. Subvfr conditions are possible
along with the possibility for locally damaging winds and large
hail. Drier conditions along with a west to northwest flow is
expected behind a cold front later Thursday night through
Friday. Winds will become light Friday night.

Local flight restrictions possible this weekend within
showers thunderstorms. Late Sunday appears to be the more likely
day for storm development to occur.

Marine
A southerly flow will strengthen over the waters tonight ahead
of a warm front. The warm front will pass through the waters
Thursday and a deep mixing layer should allow for breezy
conditions Thursday afternoon. A small craft advisory is in
effect for the middle portion of the bay and lower tidal potomac
river for southerly channeling winds overnight into Thursday
morning and an SCA is in effect for the rest of the waters
Thursday afternoon and evening.

There is a chance for severe thunderstorms Thursday afternoon
and evening, with the most likely time being between 4 pm and 8
pm. Confidence in coverage of severe storms is low, but locally
damaging wind gusts and large hail are possible later Thursday
afternoon and evening.

A cold front will stall to the south and west of the waters
Friday through Friday night, but an SCA will likely be needed
for portions of the waters during this time.

South winds will increase Saturday afternoon evening. If
ingredients come together, the setup for southerly channeling
will be there. It's unclear at this time whether SCA conditions
would result.

A cold front will drop towards the waters Sunday; however, at this
time it does not seem as though the front will make it to the bay
potomac. That would keep the preferred mixing on land.

Tides coastal flooding
A southerly flow will increase over the waters through tonight
and this will cause anomalies to increase. Minor flooding is
possible for sensitive areas with the high tide cycle late
tonight into Thursday morning, but confidence is too low at
this time for an advisory. The flow will turn toward the west
Thursday night and northwest Friday, causing anomalies to
decrease.

Lwx watches warnings advisories
Dc... None.

Md... None.

Va... None.

Wv... None.

Marine... Small craft advisory from midnight tonight to midnight edt
Thursday night for anz531>534-537-539>541-543.

Small craft advisory from noon Thursday to midnight edt
Thursday night for anz530-535-536-538-542.

Synopsis... Bjl
near term... Bjl jmg
short term... Bjl
long term... Hts
aviation... Bjl hts
marine... Bjl hts
tides coastal flooding... Bjl


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
WASD2 - 8594900 - Washington, DC 11 mi38 min S 6 G 7 70°F 71°F1023.8 hPa (-0.0)
NCDV2 36 mi44 min ESE 13 G 15 69°F 74°F1022.6 hPa
APAM2 - 8575512 - Annapolis, MD 41 mi38 min 68°F 1023.2 hPa (-0.3)
44063 - Annapolis 42 mi32 min SW 12 G 12 67°F 68°F1023.7 hPa
TPLM2 - Thomas Point, MD 42 mi38 min SSE 13 G 14 67°F 67°F1024.6 hPa (-0.6)49°F
44062 - Gooses Reef, MD 46 mi44 min S 16 G 18 66°F 1024.4 hPa
BLTM2 - 8574680 - Baltimore, MD 46 mi38 min SSW 2.9 G 6 69°F 69°F1023.2 hPa (-0.0)
CPVM2 46 mi38 min 68°F 51°F
FSKM2 - 8574728 - Francis Scott Key Bridge, MD 46 mi38 min SSW 6 G 6 69°F 1023.7 hPa (-0.0)
FSNM2 46 mi44 min SSW 7 G 8.9 69°F 1023.3 hPa

Wind History for Washington, DC
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Fort Belvoir, VA7 mi42 minSE 310.00 miFair66°F51°F60%1024 hPa
Washington/Reagan National Airport, DC, VA10 mi46 minS 610.00 miMostly Cloudy69°F48°F49%1023.7 hPa
Washington/Dulles International Airport, DC, VA16 mi46 minSSE 810.00 miMostly Cloudy67°F48°F51%1023.5 hPa
Manassas, Manassas Regional Airport/Harry P. Davis Field, VA17 mi42 minSSE 510.00 miFair65°F52°F63%1024.8 hPa
Camp Springs / Andrews Air Force Base, MD19 mi42 minSE 610.00 miFair65°F49°F57%1024.3 hPa
College Park Airport, MD19 mi55 minN 010.00 miFair69°F46°F45%1023.7 hPa
Quantico Marine Corps Airfield - Turner Field, VA22 mi1.7 hrsSSE 910.00 miFair71°F53°F53%1023.5 hPa
Gaithersburg - Montgomery County Airport, MD24 mi42 minSSE 510.00 miFair67°F48°F51%1026.8 hPa

Wind History from DAA (wind in knots)
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Last 24hrNW4CalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmSE6CalmS4S7S4SE5SE4SE5SE5SE3
1 day agoCalmNW3NW9NW15
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2 days agoS4S4S5SE4SE6SE3S4S6SW4CalmCalmSW5W6SW6S5S8SW8SW8
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S7S9S6S4E3

Tide / Current Tables for Chain Bridge, one mile below, D.C.
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Chain Bridge
Click for Map
Wed -- 05:50 AM EDT     Sunrise
Wed -- 06:05 AM EDT     0.41 feet Low Tide
Wed -- 08:57 AM EDT     Moonset
Wed -- 11:48 AM EDT     3.48 feet High Tide
Wed -- 06:56 PM EDT     0.25 feet Low Tide
Wed -- 08:20 PM EDT     Sunset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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3.12.72.11.510.60.40.61.22.12.93.43.53.22.61.91.40.80.40.30.51.222.7

Tide / Current Tables for Chain Bridge, D.C.
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Chain Bridge
Click for Map
Wed -- 05:50 AM EDT     Sunrise
Wed -- 06:10 AM EDT     0.41 feet Low Tide
Wed -- 08:57 AM EDT     Moonset
Wed -- 11:53 AM EDT     3.48 feet High Tide
Wed -- 07:01 PM EDT     0.25 feet Low Tide
Wed -- 08:20 PM EDT     Sunset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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3.12.82.21.510.60.40.51.22.12.93.33.53.22.621.40.90.50.30.51.222.6

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 (20,4,5,8)
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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.