Sunday, September19, 2021
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Marine Weather and Tides
Grasonville, MD

Version 3.4
NOTICE
3/30/2021 -- ANZ330 has been split into ANZ331 and ANZ332. Click EDIT in Marine Forecast and select your new zone.
1/26/2021 -- The West Coast Satellite images havd been updated. They now use GEOS-17.
1/1/2021 -- The 7 day forecast are now working well. Thank you NOAA for your support.

Sunrise 6:48AMSunset 7:07PM Sunday September 19, 2021 9:45 AM EDT (13:45 UTC) Moonrise 5:56PMMoonset 4:08AM Illumination 96% Phase: Waxing Gibbous; Moon at 13 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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ANZ540 Eastern Bay- 735 Am Edt Sun Sep 19 2021
.small craft advisory in effect until 11 am edt this morning...
Today..N winds 10 kt. Gusts up to 20 kt this morning. Waves 1 ft.
Tonight..E winds 5 to 10 kt. Waves 1 ft.
Mon..E winds 5 to 10 kt. Waves 1 ft.
Mon night..E winds 10 to 15 kt with gusts to 20 kt. Waves 1 ft.
Tue..E winds 10 kt. Waves 1 ft.
Tue night..SE winds 10 kt. Waves 1 ft.
Wed..SE winds 10 kt. Waves 1 ft. A chance of showers through the day, then showers likely through the night.
Thu..SE winds 10 kt...becoming w. Waves 1 ft. A chance of showers.
ANZ500 735 Am Edt Sun Sep 19 2021
Synopsis for the tidal potomac and md portion of the chesapeake bay.. High pressure will build overhead later today before moving offshore Monday and Tuesday. A strong cold front will push through the region mid-week, bringing the chance for sca conditions to return.


7 Day Forecast for Marine Location Near Grasonville, MD
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location: 38.88, -76.25     debug


Area Discussion for - Philadelphia/Mount Holly, PA
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FXUS61 KPHI 191029 AFDPHI

Area Forecast Discussion National Weather Service Mount Holly NJ 629 AM EDT Sun Sep 19 2021

SYNOPSIS. High pressure builds over eastern Canada and the Northeast later today and tonight, then moves into the Gulf of Maine on Monday. High pressure remains over the western Atlantic through the end of next week. A frontal boundary approaches for the middle of the week, and slowly crosses the region at the end of the work week. Another front may pass through next weekend.

NEAR TERM /THROUGH TONIGHT/. In the wake of the cold front earlier, and with both a surface ridge a mid level ridge building starting to build over our region, expect tranquil and seasonable conditions through tonight. Temperatures today will be 5 to 10 degrees lower than Saturday's highs, with highs mostly in the 70s (though a few places could be near 80 F).

Winds will be gradually shifting from northerly to easterly, primarily late in the day into tonight. With onshore flow, risk for fog and/or low stratus increases. However, the risk for fog appears rather low tonight as the most likely areas to get close to saturation (SE NJ and northern Delmarva) should have winds stay up near 5 kt. Across NW NJ and E Central PA, where winds will be lighter, dew points should also be lower. Thus, for now I don't have a mention of fog in the forecast. As for low stratus clouds, that is possible, but given how late the onshore flow develops, it is unlikely that we will see widespread low clouds.

SHORT TERM /MONDAY THROUGH TUESDAY/. High pressure will move into the Gulf of Maine on Monday and remains there through Tuesday. Onshore flow sets up across the region, and low level moisture will gradually increase across the region. Surface dew points will start out in the 50s on Monday, gradually rising through the 60s once again on Tuesday.

Plenty of sunshine and seasonal conditions expected on Monday with highs generally in the 70s. With increasing low level moisture, patchy fog possible late Monday night. On Tuesday, high temperatures will once again be in the 70s, but with increasing clouds as a frontal boundary approaches from the west.

LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/. Surface cold front with a deep upper trough dig through the central U.S., but with high pressure anchored offshore, the front looks to slow down over the eastern Great Lakes and Ohio Valley Tuesday night.

A period of unsettled weather is on tap for the midweek period, however, there is a good deal of uncertainty with specifics given the differences among the models.

A closed H5 low will pinch off of the upper trough over the great Lakes and Ohio Valley late Wednesday. The first wave of showers will approach the region Wednesday and Wednesday night. The issue over the following couple of days is that the 00Z/19 GFS, ECMWF, and Canadian all have different solutions regarding the timing and placement of the upper low. Overall, a period of showers is likely Wednesday night through Thursday, but showers may continue Thursday night and if the slower models pan out. Another concern is convection. Models indicating minimal MUCAPE, with the 00Z ECMWF on the more robust side, but still only around 600 J/kg. Given that surface dew points will be well in the 60s, possibly approaching 70, there is enough moisture available. The concern is that all of the ingredients might not come together. ECMWF indicating 80-100 kt jet, but the jet stays north of the region. GFS indicates this jet, but it is more over the Northeast, and is producing a period of heavy rain right over western and central New York and central and eastern Pennsylvania Wednesday night, then over New Jersey Thursday morning. The Canadian brings this rain which could be heavy to the region late Thursday and Thursday night. The ECMWF is not as progressive with that heavy rain, but is slower, bringing it Thursday night/Friday morning.

Feel best course of action is to cap PoPs at chance on Wednesday, then carry likely PoPs Wednesday night and Thursday. Will also add a chance for thunder Thursday afternoon, but it remains uncertain.

Cold front passes through the region by Friday morning, unless the ECMWF is correct, and in that case, it will not be until late Friday. Conditions dry out sometime Friday and Saturday as high pressure builds in from the north.

AVIATION /12Z SUNDAY THROUGH THURSDAY/. The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas.

Today . VFR conditions expected. Winds should primarily be northerly at 5 to 10 kt. Especially this morning, the direction could vary between 330 and 030 degrees. After 18Z, expect a slight veering to more northeasterly, especially at MIV/ACY. Moderate confidence with winds; high confidence of VFR.

Tonight . Starting VFR, and should generally stay VFR through the night. Some low clouds (with potential MVFR ceilings) are possible after 06Z, primarily at KMIV, KACY, KPHL, and KILG. Winds will settle out of the east or northeast with speeds generally 5 kt or less. Moderate confidence on the overall pattern, but low confidence on the potential for MVFR ceilings.

Outlook .

Monday . VFR. E-SE winds 5-10 kt, except 10-15 kt at KACY. High confidence.

Monday night . VFR initially, then sub-VFR in fog/stratus. E winds 5 kt or less. Moderate confidence.

Tuesday . VFR. SE winds 5-10 kt. Moderate confidence.

Tuesday night . VFR initially, then sub-VFR possible in fog/stratus. E winds 5 kt or less. Moderate confidence.

Wednesday through Wednesday night . Overall, VFR, but scattered SHRA possible in the afternoon, then becoming likely Wednesday night with sub-VFR conditions. SE winds 10-15 kt, with gusts to 20 kt in the afternoon. Low confidence.

Thursday . SHRA likely with sub-VFR conditions. TSRA possible in the afternoon. SE winds 10-20 kt. Low confidence.

MARINE. Winds and seas should stay below Small Craft Advisory criteria through tonight. Some guidance shows seas on the NJ coastal waters getting to 5 feet this afternoon. However, that guidance is too high with current conditions, so expect that bias to continue and thus think seas should stay just below SCA criteria.

Outlook .

Tuesday-Thursday . Although winds should remain below advisory levels through the period, seas could increase to 5 feet or higher by Tuesday night and continue into Thursday.

Rip currents .

The combination of lingering swells from Odette, with developing onshore flow later today, and the full moon on Monday will result in a moderate risk for rip currents today and Monday. Although the swells should start to diminish, this tendency will be offset by the increasing onshore flow.

TIDES/COASTAL FLOODING. Spotty minor tidal flooding is possible centered around the highest astronomical tides through Monday. The combination of increased swells from Odette, higher astronomical tides with the full moon on Monday, and developing onshore flow will all contribute to this. The highest astronomical tides, and thus the higher risk for spotty minor flooding, will be the evening/overnight high tides. At this point, tidal levels just should fall just shy of advisory criteria. However, if the onshore flow develops faster than what is currently expected, there could be an increased risk for widespread minor flooding, especially with the evening/night high tide tonight.

Notably, forecasts have increased slightly for portions of the Atlantic coast in southern New Jersey and Delaware for the evening/night high tide tonight, and there is a chance an advisory may be required for these areas as well as adjacent portions of Delaware Bay during this time frame.

PHI WATCHES/WARNINGS/ADVISORIES. PA . None. NJ . None. DE . None. MD . None. MARINE . None.

Synopsis . MPS Near Term . Johnson Short Term . MPS Long Term . MPS Aviation . Johnson/MPS Marine . Johnson/MPS Tides/Coastal Flooding . WFO PHI


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
TPLM2 - Thomas Point, MD 10 mi45 min N 15 G 17 72°F 77°F1022.2 hPa (+1.6)
CPVM2 11 mi57 min 73°F 62°F
44063 - Annapolis 12 mi51 min NNE 16 G 19 73°F 77°F1 ft1022.4 hPa
APAM2 - 8575512 - Annapolis, MD 14 mi57 min NNW 6 G 9.9 76°F 79°F1021.1 hPa
CA2 - 8571892 - Cambridge, MD 23 mi57 min N 5.1 G 7 72°F 78°F1021 hPa
TCBM2 - 8573364 - Tolchester Beach, MD 23 mi57 min NNE 5.1 G 11 71°F 77°F1021.7 hPa
44062 - Gooses Reef, MD 24 mi51 min NNE 14 G 19 73°F 78°F1 ft1022.2 hPa
BSLM2 - Chesapeake Bay, MD 25 mi75 min NE 1 59°F 1021 hPa58°F
FSKM2 - 8574728 - Francis Scott Key Bridge, MD 28 mi57 min NE 6 G 8.9 71°F 1021.7 hPa
FSNM2 28 mi57 min N 8 G 14 70°F 1021.5 hPa
BLTM2 - 8574680 - Baltimore, MD 32 mi57 min ENE 8.9 G 15 71°F 79°F1021.3 hPa
COVM2 - 8577018 - Cove Point LNG Pier, MD 34 mi57 min N 12 G 14 73°F 1021 hPa
SLIM2 - 8577330 - Solomons Island, MD 40 mi57 min NNE 9.9 G 12 74°F 79°F1020.7 hPa
WASD2 - 8594900 - Washington, DC 41 mi57 min NNE 5.1 G 8.9 74°F 78°F1021.3 hPa
DRSD1 - Delaware Reserve, DE 45 mi75 min N 6 69°F 1021 hPa68°F
BISM2 - 8571421 - Bishops Head, MD 47 mi63 min NNE 8.9 G 14 74°F 78°F1020.7 hPa

Wind History for Tolchester Beach, MD
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Easton / Newman Field, MD11 mi55 minN 810.00 miFair72°F72°F100%1022.3 hPa
Annapolis, United States Naval Academy, MD14 mi51 minN 710.00 miFair74°F60°F62%1021.8 hPa

Link to 5 minute data for KW29

Wind History from W29 (wind in knots)
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S7S6SE5SE4SE6SE6SE9SE10S6Calm
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2 days agoS3S6S5S7SE6CalmSE3NW3CalmCalmE3CalmSE4SE5S7S9S8S9S7W6S6S10
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Tide / Current Tables for Claiborne, Eastern Bay, Maryland
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Claiborne
Click for Map
Sun -- 03:39 AM EDT     1.88 feet High Tide
Sun -- 05:08 AM EDT     Moonset
Sun -- 06:50 AM EDT     Sunrise
Sun -- 10:34 AM EDT     0.53 feet Low Tide
Sun -- 03:45 PM EDT     1.52 feet High Tide
Sun -- 06:55 PM EDT     Moonrise
Sun -- 07:06 PM EDT     Sunset
Sun -- 10:11 PM EDT     0.41 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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11.31.71.81.91.81.51.310.70.60.50.711.31.51.51.41.20.90.70.50.40.5

Tide / Current Tables for Baltimore Harbor Approach, Maryland Current
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Baltimore Harbor Approach
Click for Map
Sun -- 01:06 AM EDT     0.00 knots Slack
Sun -- 04:27 AM EDT     0.96 knots Max Flood
Sun -- 05:08 AM EDT     Moonset
Sun -- 06:50 AM EDT     Sunrise
Sun -- 07:41 AM EDT     -0.00 knots Slack
Sun -- 10:52 AM EDT     -0.95 knots Max Ebb
Sun -- 02:08 PM EDT     0.00 knots Slack
Sun -- 05:05 PM EDT     0.80 knots Max Flood
Sun -- 06:56 PM EDT     Moonrise
Sun -- 07:06 PM EDT     Sunset
Sun -- 08:05 PM EDT     -0.00 knots Slack
Sun -- 11:07 PM EDT     -0.81 knots Max Ebb
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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-0.4-00.40.70.90.90.70.3-0.1-0.6-0.9-0.9-0.8-0.5-0.10.40.70.80.70.40-0.4-0.7-0.8

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