Marine Weather and Tides
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 6:21AM||Sunset 7:57PM||Friday August 18, 2017 2:49 AM EDT (06:49 UTC)||Moonrise 1:51AM||Moonset 4:36PM||Illumination 17%|
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|ANZ538 Patapsco River Including Baltimore Harbor- 131 Am Edt Fri Aug 18 2017 |
Overnight..S winds 5 to 10 kt. Waves 1 ft. A chance of showers with a slight chance of tstms.
Fri..S winds 5 to 10 kt. Waves 1 ft. Scattered showers and tstms.
Fri night..W winds 5 to 10 kt. Waves 1 ft or less. Numerous showers and tstms.
Sat..W winds 5 kt. Waves less than 1 ft.
Sat night..NW winds around 5 kt. Waves 1 ft or less.
Sun..NW winds around 5 kt. Waves flat.
Sun night..SE winds around 5 kt. Waves flat.
Mon..S winds around 5 kt. Waves 1 ft or less.
Tue..SW winds 5 kt. Waves less than 1 ft. A chance of showers and tstms through the night. Winds and waves higher and visibilities lower in and near tstms.
|ANZ500 131 Am Edt Fri Aug 18 2017 |
Synopsis for the tidal potomac and md portion of the chesapeake bay.. A cold front will approach Friday, then pass through Friday night into early Saturday. High pressure will build to the north and west of the waters while a pressure trough will remain nearby for later Saturday and Sunday. The high pressure will shift offshore early next week.
7 Day Forecast for Marine Location Near Arden on the Severn, MDHourly EDIT Help
Area Discussion for - Baltimore, MD/Washington  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxus61 klwx 180128|
area forecast discussion
national weather service baltimore md washington dc
928 pm edt Thu aug 17 2017
A warm front will exit the area to the northeast tonight. A cold
front will approach from the west Friday before crossing the
region Friday night. Surface high pressure will build in
Saturday, but an upper level disturbance will cross the region
Saturday night. A warm front will advance back north across the
region early next week, followed by a strong cold front in the
middle of the week.
Near term until 6 am Friday morning
Scattered storms exist from cumberland to charlottesville,
advancing northeast. These are likely tied to a theta-e ridge
and developing modest low level jet. Even though hi-res guidance
generally shows a weakening trend over the next several hours,
would not be surprised if showers and storms persist continue to
develop due to the forcing and around 2000 j kg of MUCAPE per
mesoanalysis and 00z iad sounding. Will carry chance pops
through most of the night, as elevated instability will remain
in place. The isolated severe threat should be waning though
due to increasing surface inhibition. Precipitable water values
near 2 inches and deep warm cloud layers suggest heavy rain will
be the biggest threat, though so far storms have been
exhibiting reasonable motion.
Where skies clear, we could get some patchy fog again,
especially in places which saw rain today. Lows will stay very
warm with the high dew points, with 70s common.
Short term 6 am Friday morning through Saturday night
Patchy fog will be a concern early Friday, but not expecting
widespread dense fog, and it should break fairly quickly once
the Sun rises.
Probably the biggest forecast concern is the threat of severe
weather on Friday afternoon. While it is certainly not the best
set up, very high pw's in excess of 2 inches (potentially above
2.25 inches) and surface temps perhaps into the low 90s with
surface dew points into the mid 70s and shear of 25-35 knots,
and the surface cold front moving into it, will likely get some
sort of line of storms going by early afternoon, which will then
slowly push east across the region. Best time in the cities
looks like mid-late afternoon, with storms lingering into the
evening east of i-95 into southern md. Training storms could
easily produce flash flooding as well. SPC has outlooked the
region for marginal severe threat, while wpc has outlooked the
region for slight risk of excessive rainfall.
The hot and humid airmass will result in high heat indices.
Using the best performing model blends results in a heat index
of 100 to locally 105 east of the blue ridge and upper 90s
west. Best chance of reaching criteria will likely be along i-95
corridor which will have the longest heating before storms
arrive. Will allow midnight shift to make the call on an
advisory based on the latest cloud convective trends.
Front slides in later Friday night, with some drying and
cooling. Lows will be a bit cooler than tonight, with some areas
returning to the 60s. Surface high presses into the region
Saturday and Saturday night, but a trough aloft may result in
isolated storms late in the day into the evening. For now have
kept pops mainly NW of the cities, but these may need to be
expanded south and east if confidence in storms grows. Highs
Saturday will be in the 80s. Temps will cool a bit more at
night, with 60s more common.
Long term Sunday through Thursday
High pressure will keep dry conditions on Sunday as it slowly
moves offshore Sunday night into Monday. Southerly flow settles
in advecting moisture into our region Monday and Tuesday. A
pressure trough at the surface could trigger showers and
thunderstorms Monday and Tuesday afternoon and evening. A cold
front will approach from the northwest on Wednesday and move
across on Wednesday night. High pressure returns on Thursday.
High temperatures during this period will be in the mid to upper
80s in northern maryland... To low 90s in central virginia at
times... And 70s at higher elevations.
Aviation 01z Friday through Tuesday
Scattered thunderstorms are a concern at all terminals until at|
least late this evening. Some weakening is seen in radar trends,
but will not rule out storms reaching the metros due to modest
low level jet forcing on elevated instability.
Late tonight concern shifts to low clouds and fog potential.
Given variable clouds and uncertainty in storm coverage, it is
still difficult to place exact timing and severity of any
restrictions. 18z guidance suggests the best chance for low
clouds will be along the i-95 corridor. Have generally held tafs
at MVFR for now, but ifr not out of the question.
We should see improvement Friday just in time for the next
round of thunderstorms on Friday afternoon. This activity will
be more organized with the cold front, with a better severe
threat, along with a better chance of low cig and vis with
storms. Generally should improve toVFR by Saturday morning,
with a much lower (though not zero) risk of storms late Saturday
as an upper level trough crosses the region behind the surface
Vfr conditions expected Sunday into Tuesday, with short periods
of sub-vfr conditions mainly Monday and Tuesday afternoon due
to possible showers and thunderstorms.
Southerly channeling ongoing with occasional gusts to 20 kt.
Expanded the SCA to pooles island on the bay zones due to better
mixing potential of a low level jet on the open waters. Have
carried the northern two zones until 6 am, when the jet should
weaken. However, SCA conditions will still be possible farther
south into Friday, ending Friday night as the cold front slides
southward into the area. Further adjustments to the SCA are
Otherwise, main concern will be for thunderstorms. Can't rule
out a storm tonight, although the threat for strong storms is
lowering. The strongest storms will likely be Friday afternoon
into evening. Winds diminish and storms end Saturday morning,
but a few isolated storms can't be ruled out late Saturday as an
upper level disturbance moves across the region.
Mainly dry conditions expected Sunday into Tuesday, with
periods of showers and thunderstorms possibly developing Monday
and Tuesday afternoon. Wind gusts are expected to stay below the
small craft advisory threshold.
Tides coastal flooding
Southerly winds will be increasing anomalies up to one foot
above normal. Have gone ahead and issued advisories for straits
point and dc SW waterfront since observations seem to be
exceeding forecasts (advisory already in place for annapolis).
Alexandria will be close, but some time to make that decision
since high tide is around 5:30 am. The following high tide is
lower astronomically, so am not seeing a threat for that one.
With continued south winds, additional advisories may be
needed Friday before the front brings a NW flow and allows
anomalies to drop Saturday.
Lwx watches warnings advisories
Dc... Coastal flood advisory from 3 am to 7 am edt Friday for dcz001.
Md... Coastal flood advisory until 8 am edt Friday for mdz014.
Coastal flood advisory until 1 am edt Friday for mdz017.
Marine... Small craft advisory until 1 am edt Saturday for anz533-534-
Small craft advisory until 6 am edt Friday for anz531-532.
near term... Ads rcm
short term... Ads rcm
long term... Imr
aviation... Ads imr rcm
marine... Ads imr rcm
tides coastal flooding... Ads rcm
Weather Reporting StationsEDIT (on/off)  Help NOTE: Click on distance to see the station location on a map
|Stations||Dist||Age||Wind||Air Temp||Water Temp||Waves||Pressure||DewPt|
|APAM2 - 8575512 - Annapolis, MD||8 mi||49 min||79°F||1011.6 hPa (-1.9)|
|44063 - Annapolis||10 mi||39 min||SSW 16 G 19||80°F||2 ft||1012.5 hPa|
|FSKM2 - 8574728 - Francis Scott Key Bridge, MD||11 mi||49 min||S 9.9 G 13||80°F||1011.8 hPa (-1.9)|
|CPVM2||11 mi||49 min||80°F||79°F|
|44043 - Patapsco, MD||12 mi||39 min||S 14 G 16||80°F||1 ft||1012.4 hPa|
|TPLM2 - Thomas Point, MD||14 mi||49 min||S 18 G 20||80°F||80°F|
|BLTM2 - 8574680 - Baltimore, MD||14 mi||49 min||SW 1.9 G 5.1||79°F||83°F||1011.6 hPa (-1.9)|
|TCBM2 - 8573364 - Tolchester Beach, MD||20 mi||49 min||SE 6 G 8||76°F||80°F||1012.4 hPa (-1.9)|
|BSLM2 - Chesapeake Bay, MD||21 mi||139 min||SSE 4.1||68°F||1013 hPa||67°F|
|WASD2 - 8594900 - Washington, DC||27 mi||49 min||S 7 G 8||80°F||80°F||1011.5 hPa (-1.5)|
|44062 - Gooses Reef, MD||37 mi||39 min||S 14 G 16||80°F||2 ft||1012.9 hPa|
|44057 - Susquehanna, MD||42 mi||39 min||S 7.8 G 9.7||77°F||1012.5 hPa|
|CA2 - 8571892 - Cambridge, MD||44 mi||49 min||77°F||81°F||1013.4 hPa (-1.7)|
|COVM2 - 8577018 - Cove Point LNG Pier, MD||47 mi||49 min||S 14 G 16||79°F||1013 hPa (-1.9)|
Wind History for Francis Scott Key Bridge NE Tower, MD(wind in knots) EDIT (on/off)  Help
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports
|Annapolis, United States Naval Academy, MD||8 mi||55 min||S 7||10.00 mi||Fair||79°F||77°F||94%||1012.1 hPa|
|Fort Meade / Tipton, MD||10 mi||61 min||N 0||5.00 mi||Overcast||72°F||69°F||94%||1013.2 hPa|
|Baltimore, Baltimore-Washington International Airport, MD||10 mi||55 min||S 3||10.00 mi||Mostly Cloudy||76°F||73°F||91%||1012 hPa|
|Bay Bridge Field, MD||15 mi||64 min||SSE 6||10.00 mi||Fair||77°F||73°F||89%||1012.5 hPa|
|Baltimore, Inner Harbor, MD||15 mi||55 min||no data||mi||80°F||73°F||79%||1012.3 hPa|
|College Park Airport, MD||19 mi||61 min||N 0||10.00 mi||Partly Cloudy||76°F||71°F||84%||1012.2 hPa|
|Baltimore / Martin, MD||20 mi||52 min||SE 7||10.00 mi||Partly Cloudy||79°F||77°F||94%||1012.5 hPa|
|Camp Springs / Andrews Air Force Base, MD||23 mi||51 min||S 5||10.00 mi||Mostly Cloudy||74°F||71°F||90%||1012.6 hPa|
Wind History from NAK (wind in knots)
|1 day ago||N||NW||N||NE||Calm||Calm||NW||N||Calm||SE||SE||SE||SE||SE||SE||SE||NE||Calm||Calm||Calm||Calm||Calm||Calm||Calm|
|2 days ago||Calm||Calm||Calm||W||E||E||SE||SE||SE||SE||S||Calm||NW|
EDIT RT Ports Option Weekend mode (on/off) (on/off)  Help One Week of Data
|Cedar Point |
Click for Map
Fri -- 02:50 AM EDT Moonrise
Fri -- 03:19 AM EDT 1.28 feet High Tide
Fri -- 06:22 AM EDT Sunrise
Fri -- 10:44 AM EDT 0.36 feet Low Tide
Fri -- 03:25 PM EDT 0.81 feet High Tide
Fri -- 05:36 PM EDT Moonset
Fri -- 07:56 PM EDT Sunset
Fri -- 09:30 PM EDT 0.19 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
EDIT (on/off)  Help One Week of Data
|Baltimore Harbor Approach |
Click for Map
Fri -- 02:26 AM EDT 1.12 knots Max Flood
Fri -- 02:50 AM EDT Moonrise
Fri -- 06:02 AM EDT -0.00 knots Slack
Fri -- 06:21 AM EDT Sunrise
Fri -- 09:16 AM EDT -0.93 knots Max Ebb
Fri -- 12:53 PM EDT 0.00 knots Slack
Fri -- 03:17 PM EDT 0.46 knots Max Flood
Fri -- 05:35 PM EDT Moonset
Fri -- 05:45 PM EDT -0.00 knots Slack
Fri -- 07:55 PM EDT Sunset
Fri -- 08:54 PM EDT -0.69 knots Max Ebb
Fri -- 11:41 PM EDT 0.00 knots Slack
Tide / Current data from XTide NOT FOR NAVIGATION
Weather Map and Satellite Images(on/off)  Help
|Weather Map ||IR Satellite Image from GEOS|
GOES Local Image of Mid-Atlantic EDIT
Wind Forecast for Baltimore, MD/Washington (2,6,7,8)(on/off)  Help
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