Sunday, December16, 2018 L-36.com


Marine Weather and Tides
Riva, 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 7:17AMSunset 4:46PM Sunday December 16, 2018 10:24 PM EST (03:24 UTC) Moonrise 1:10PMMoonset 12:32AM Illumination 71% Phase: Waxing Gibbous; Moon at 9 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
    EDIT      (on/off)   Help
ANZ532 Chesapeake Bay From Sandy Point To North Beach- 951 Pm Est Sun Dec 16 2018
.small craft advisory in effect until midnight est tonight...
.small craft advisory in effect from Monday morning through late Monday night...
Rest of tonight..NW winds 10 to 15 kt with gusts to 20 kt. Waves 2 ft.
Mon..NW winds 10 to 15 kt. Gusts up to 20 kt... Increasing to 30 kt in the afternoon. Waves 2 to 3 ft.
Mon night..NW winds 10 to 15 kt with gusts to 30 kt. Waves 3 ft.
Tue..NW winds 10 to 15 kt with gusts to 25 kt. Waves 2 ft.
Tue night..NW winds 5 to 10 kt. Waves 1 ft.
Wed..S winds 5 to 10 kt. Waves 1 ft.
Wed night..S winds 5 to 10 kt. Waves 1 ft.
Thu..SE winds 10 to 15 kt. Waves 1 to 2 ft. Showers.
Fri..SW winds 10 to 15 kt. Waves 1 to 2 ft. Showers likely through the day, then a chance of showers through the night.
ANZ500 951 Pm Est Sun Dec 16 2018
Synopsis for the tidal potomac and md portion of the chesapeake bay.. Low pressure off the coast of new jersey will continue to move northeast and away from the region. A cold front approaching from the great lakes will cross the waters late Monday. High pressure will follow through Wednesday. Small craft advisories will likely be needed for portions of the waters Monday night through Tuesday. Gales will be possible late Monday afternoon and Monday evening.


7 Day Forecast for Marine Location Near Riva, MD
   Hourly   EDIT   Help
location: 38.89, -76.6     debug


Area Discussion for - Baltimore, MD/Washington
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
Fxus61 klwx 170210
afdlwx
area forecast discussion
national weather service baltimore md washington dc
910 pm est Sun dec 16 2018

Synopsis
Low pressure will move out to sea tonight. A cold front
approaching from the great lakes will cross the mid- atlantic
Monday afternoon. High pressure will follow Tuesday through
Wednesday, before another large area of low pressure approaches
from the tennessee valley later Thursday and Friday.

Near term until 6 am Monday morning
Coastal low is located east of new jersey this evening.

Precipitation has departed (east of the allegheny front anyway).

However, a subsidence inversion exists and moisture in the
cyclonic flow is continuing to result in clouds. There has been
a gradual decreasing trend, and models show moisture should thin
by later tonight, so will continue to show a clearing trend.

Nocturnal decoupling has seemed to limit the mixing of stronger
wind gusts behind the low, although full decoupling is only
likely in the valleys piedmont locations to the south and west.

Temperatures in these locations may dip below freezing, but
should stay in the mid 30s elsewhere. Don't feel confident in
any blanket moisture re-freeze statements at this point due to
uncertainty in clouds and temperatures, but isolated problems
aren't out of the question. Will pass this concern on to the
midnight shift. Some patchy fog could develop in low lying areas
where it is clear.

In the mountains, models continue to indicate potential for
light precipitation overnight. So far temperatures are remaining
above freezing, but will drop below freezing at the highest
elevations late. Given shallow moisture, fog, drizzle, and
perhaps some flurries are most likely if precipitation occurs.

Think any potential impact from freezing drizzle or fog is very
limited.

Short term 6 am Monday morning through Wednesday
A spoke of northern stream energy will drop a boundary
southward across the northeastern united states. This boundary
is subtle at the surface-- there is barely a wind shift and
limited associated precipitation-- however it is clearly evident
in thermal fields, especially at 925-850 mb. The cold advection
will arrive late in the day, so we'll be able to pull off a
mostly sunny and mild Monday. Highs will be slightly above
normal... Particularly dc-charlottesville southeast where temps
will crack 50 degrees.

Along and behind the front, 20-25 kt readily available in the
mixed layer. Depending upon output, there are some suggestions
of close to 30 kt. They gusty winds, and associated temperature
drop, will carry through the evening before conditions calm
slightly overnight.Aside from perhaps the heart of the urban
downtowns or along the immediate shoreline of the chesapeake
bay, all sites will drop below freezing.

Tuesday through Wednesday will be the tranquil part of the
forecast, as high pressure crests overhead. Winds may still be
a pinch gusty early Tuesday before the pressure gradient
relaxes. Once again, temperatures will be at or below normal.

Long term Wednesday night through Sunday
Main story in the long term is another large trough of low pressure
progged to impact the area Thursday night through early Saturday.

Once again, deep-layer southerly flow will result in copious amounts
of gulf and atlantic moisture streaming into the area. Though the
exact track and strength of low pressure and subsequent
precipitation amounts remain in question, widespread rainfall over
an inch seems plausible given the deep, moist and slow moving nature
of the system. Wintry precipitation over the higher elevations may
be more of an issue as well since there will be a little more cold
air nearby for the system to draw in as it lifts away, but again
details remain to be seen.

Aviation 02z Monday through Friday
Clouds through the middle portion of the night could be quite
variable between MVFR andVFR, with breaks at times. Still a
good bit of moisture in the cyclonic flow from the departing low
pressure system, so persistent clearing is a bit in question,
though most guidance indicatesVFR by late tonight. A few stray
gusts are possible in NW flow, but appears the boundary layer
has decoupled.

AlthoughVFR is most probable on Monday, there may be some lower
stratocu as a secondary front disturbance crosses (have kept
these as few sct). There will be two periods of gusty winds:
one Monday (nw winds g20kt) and another behind a cold front
Monday night (g20-25kt).

MainlyVFR expected tue-thu, winds becoming S as high pressure
moves offshore by thu.

Marine
Winds remain elevated with scattered gusts to 20 knots over the
chesapeake bay and lower potomac as low pressure deepens east
of new jersey. Small craft advisories will gradually pare back
overnight to the mid bay and lower tidal potomac. But mixing
improves again by mid-morning Monday, and will be reinforced by
a cold front Monday night. Have issued a small craft advisory
for all waters for this period. Behind the front, winds likely
will approach gale warning conditions. Since its the third
period in the new forecast cycle and confidence not high, have
capped winds just below. However, this threat is mentioned in
the marine synopsis and hazardous weather outlook.

Winds will gradually relax Tuesday as high pressure begins to
build. May have some lingering small craft conditions. Winds
should remain below SCA levels Tue night-thu as high pressure
moves across the waters.

Hydrology
Rainfall has tapered off. However, with widespread 2-3 inches
of rain having fallen, and areas of up to 4 inches, some
locations continue to have ongoing flood issues. Detailed local
information and updates can be found in the various flood
warnings. We will be dropping the flood warnings once
conditions permit.

In addition, many larger streams and rivers will continue
rising today as the heavy rainfall continues to drain into these
waterways. A flood threat will remain on the mainstem rivers into
the early portion of the work week. See the latest river flood
watches and warnings for more information about these.

Tides coastal flooding
A low astronomical tide as allowed for coastal flooding
concerns to be squelched in the near term. Current anomalies are
running 1 to 1.5 feet above normal. The threat for flooding
does increase tonight and on Monday at georgetown and southwest
waterfront with the influx of freshwater making its way down the
potomac river.

Guidance signals continue to indicate that there is a
significant flood risk at georgetown, with a crest somewhere in
the 8.5-9.0 ft range late Monday afternoon. While don't have
rock-solid confidence that will be the precise crest, have a
greatly heightened concern that there will be moderate flooding
on the upper tidal potomac river, especially near the interface
with freshwater input (key bridge). Therefore, have issued a
lengthy coastal flood warning for washington dc.

Freshwater flooding typically spreads out downstream. While the
southwest waterfront likely won't receive as extensive of a
period of flooding, there is a risk of a cycle of moderate
inundation there too, on Monday afternoon, with the early Monday
morning and early Tuesday morning cycles likely be be exceeding
the minor threshold.

The impact at alexandria likely to be less as freshwater input
typically fans out. However, minor flooding cannot be ruled out
somewhere during this timeframe. Once confidence grows, an
advisory may be required at some point.

Climate
Rainfall totals continue to creep upward, with baltimore md and
washington dc setting the annual record already. Here are the
current rankings for wettest year on record (through 4 pm december
16th):
washington dc area (dca)
1. 64.22 inches (2018)
2. 61.33 inches (1889)
weather records for the washington dc area have been kept at
what is now ronald reagan washington national airport (dca)
since 1945. Precipitation records observed downtown extend the
period of record back to 1871.

Baltimore md area (bwi)
1. 68.82 inches (2018)
2. 62.66 inches (2003)
weather records for the baltimore md area have been kept at
what is now baltimore-washington international thurgood marshall
airport (bwi) since 1950. Precipitation records observed
downtown extend the period of record back to 1871.

Dulles va area (iad)
1. 65.67 inches (2003)
2. 64.36 inches (2018)
3. 59.05 inches (1972)
weather records have been kept at what is now washington dulles
international airport (iad) since 1960.

Note: all climate data are considered preliminary until
reviewed by the national centers for environmental information
(ncei).

Lwx watches warnings advisories
Dc... Coastal flood warning until 1 pm est Tuesday for dcz001.

Md... None.

Va... None.

Wv... None.

Marine... Small craft advisory until midnight est tonight for anz530>532-
538>540.

Small craft advisory from 10 am Monday to 1 am est Tuesday for
anz530>532-535-536-538>540.

Small craft advisory from midnight tonight to 1 am est Tuesday
for anz542.

Small craft advisory until 1 am est Tuesday for anz533-534-537-
541-543.

Synopsis... Hts
near term... Ads hts
short term... Hts
long term... Dhof
aviation... Ads hts dhof
marine... Ads hts dhof
hydrology... Hts
tides coastal flooding... Hts
climate... Lwx


Weather Reporting Stations
   EDIT       (on/off)   Help   NOTE: Click on distance to see the station location on a map
Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
TPLM2 - Thomas Point, MD 9 mi24 min WNW 12 G 13 41°F 43°F1013.5 hPa (+0.6)39°F
APAM2 - 8575512 - Annapolis, MD 9 mi36 min 42°F 1012.1 hPa
BSLM2 - Chesapeake Bay, MD 9 mi114 min NNW 5.1 42°F 1013 hPa39°F
CPVM2 13 mi36 min 42°F 42°F
WASD2 - 8594900 - Washington, DC 22 mi36 min NW 4.1 G 8 42°F 41°F1013.4 hPa
FSNM2 23 mi42 min NW 14 G 16 42°F 1011.9 hPa
FSKM2 - 8574728 - Francis Scott Key Bridge, MD 23 mi36 min NW 13 G 15 42°F 1012.3 hPa
BLTM2 - 8574680 - Baltimore, MD 26 mi48 min N 6 G 9.9 42°F 44°F1012 hPa
TCBM2 - 8573364 - Tolchester Beach, MD 29 mi36 min NNW 9.9 G 12 41°F 44°F1012.4 hPa
COVM2 - 8577018 - Cove Point LNG Pier, MD 36 mi36 min NNW 13 G 16 42°F 1013.1 hPa
CA2 - 8571892 - Cambridge, MD 36 mi48 min 41°F 43°F1011.9 hPa
SLIM2 - 8577330 - Solomons Island, MD 40 mi36 min NW 9.9 G 14 42°F 44°F1012.4 hPa
NCDV2 46 mi48 min NW 5.1 G 8.9 42°F 44°F1012.8 hPa

Wind History for Washington, DC
(wind in knots)    EDIT      (on/off)   Help
11
PM
12
AM
1
AM
2
AM
3
AM
4
AM
5
AM
6
AM
7
AM
8
AM
9
AM
10
AM
11
AM
12
PM
1
PM
2
PM
3
PM
4
PM
5
PM
6
PM
7
PM
8
PM
9
PM
10
PM
Last
24hr
N6
N5
G10
N5
G11
N5
G11
N4
G13
NE3
G8
E3
G11
NE4
N4
G9
N5
G9
N4
G10
N5
G11
N6
G12
N3
G10
N4
G8
N6
G12
N5
G10
N7
G16
N4
G13
NW6
G11
NW9
N5
G11
NW5
G8
NW5
G8
1 day
ago
NE4
N3
G8
NE4
G9
N3
NE5
G10
NE2
G8
NE1
G7
NE2
G7
NE4
G9
SE1
G8
NE4
G9
NE3
G7
N6
G9
N5
G12
NE4
G12
E5
G10
NE3
G7
NE2
G11
N5
G9
NE5
G10
NE4
G8
NE3
NE3
N4
G8
2 days
ago
NE4
E3
E2
E3
E2
S1
NE1
NE1
--
E1
N2
G6
NE1
NE2
SW1
W2
--
SW2
E1
G5
NE2
E1
G4
NE2
NE2
G7
N4
G8
NE3
G6

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Annapolis, United States Naval Academy, MD9 mi30 minWNW 510.00 miOvercast44°F37°F79%1012.6 hPa
Bay Bridge Field, MD15 mi44 minNW 810.00 miOvercast41°F39°F93%1012.5 hPa
Camp Springs / Andrews Air Force Base, MD15 mi28 minWNW 710.00 miMostly Cloudy40°F36°F88%1013.4 hPa
Fort Meade / Tipton, MD16 mi42 minNW 410.00 miOvercast39°F37°F93%1013.5 hPa
College Park Airport, MD18 mi42 minN 010.00 miFair39°F35°F85%1012.9 hPa
Baltimore, Baltimore-Washington International Airport, MD21 mi30 minNW 510.00 miMostly Cloudy41°F37°F89%1012.4 hPa
Washington/Reagan National Airport, DC, VA23 mi32 minVar 410.00 miOvercast44°F37°F76%1013.3 hPa

Wind History from NAK (wind in knots)
11
PM
12
AM
1
AM
2
AM
3
AM
4
AM
5
AM
6
AM
7
AM
8
AM
9
AM
10
AM
11
AM
12
PM
1
PM
2
PM
3
PM
4
PM
5
PM
6
PM
7
PM
8
PM
9
PM
10
PM
Last 24hrNE6NE5N4N6NE8NE12
G27
NE10N7NE8N5N10N10N11N10N11N11NW11NW10NW13
G19
NW10NW10NW8NW7NW5
1 day agoN3N4N8N7N7N12N11NE9N7NE9NE9NE6N9N10
G20
N12NE10
G21
NE9
G16
NE9NE6N6NE11NE6NE8NE8
G17
2 days agoCalmCalmN3CalmCalmN4N3NW3N3N3CalmN5CalmCalmCalmN3CalmNW3N3N3N4N44Calm

Tide / Current Tables for Rhode River (County Wharf), Maryland
   EDIT   RT Ports Option   Weekend mode (on/off)   (on/off)   Help   One Week of Data
Rhode River (County Wharf)
Click for Map
Sun -- 12:32 AM EST     Moonset
Sun -- 05:09 AM EST     -0.04 feet Low Tide
Sun -- 07:18 AM EST     Sunrise
Sun -- 11:18 AM EST     0.79 feet High Tide
Sun -- 01:09 PM EST     Moonrise
Sun -- 04:45 PM EST     Sunset
Sun -- 05:20 PM EST     0.19 feet Low Tide
Sun -- 11:11 PM EST     0.87 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

12
am
1
am
2
am
3
am
4
am
5
am
6
am
7
am
8
am
9
am
10
am
11
am
12
pm
1
pm
2
pm
3
pm
4
pm
5
pm
6
pm
7
pm
8
pm
9
pm
10
pm
11
pm
0.80.60.40.20-0-00.10.30.50.70.80.80.70.50.40.30.20.20.30.50.60.80.9

Tide / Current Tables for Baltimore Harbor Approach, Maryland Current
   EDIT      (on/off)   Help   One Week of Data
Baltimore Harbor Approach
Click for Map
Sun -- 12:31 AM EST     Moonset
Sun -- 02:12 AM EST     -0.00 knots Slack
Sun -- 05:41 AM EST     -0.75 knots Max Ebb
Sun -- 07:17 AM EST     Sunrise
Sun -- 08:56 AM EST     0.00 knots Slack
Sun -- 12:18 PM EST     0.80 knots Max Flood
Sun -- 01:08 PM EST     Moonrise
Sun -- 03:48 PM EST     -0.00 knots Slack
Sun -- 04:44 PM EST     Sunset
Sun -- 06:40 PM EST     -0.56 knots Max Ebb
Sun -- 09:45 PM EST     0.00 knots Slack
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

12
am
1
am
2
am
3
am
4
am
5
am
6
am
7
am
8
am
9
am
10
am
11
am
12
pm
1
pm
2
pm
3
pm
4
pm
5
pm
6
pm
7
pm
8
pm
9
pm
10
pm
11
pm
0.50.30.1-0.2-0.5-0.7-0.7-0.6-0.300.40.70.80.80.60.3-0.1-0.3-0.5-0.6-0.4-0.20.10.3

Weather Map and Satellite Images
       (on/off)   HelpWeather Map
wmap_A
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.
Link to Loop

Other links: Northern Pacific     Contential US     Full GOES-East
Wind Forecast for Baltimore, MD/Washington (22,6,7,8)
      (on/off)   Help

Ground Weather Radar Station Dover AFB, DE
   (on/off)   Help
weather_mapweather_map weather_map

Ad by Google

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.