Marine Weather and Tides
12/16/2019 NOAA is having trouble with requests that include wind gusts. I am posting graphs without wind gusts until it gets fixed.
10/9/2019 Updated the Marine Zones.
9/4/2019 Fixed the weather maps due to NOAA moving them.
7/25/2019 New feature in the Airports section gives a link to 5 minute updates for data reports.
|Sunrise 6:18AM||Sunset 8:23PM||Thursday August 6, 2020 8:47 PM EDT (00:47 UTC)||Moonrise 9:24PM||Moonset 8:05AM||Illumination 91%|
7 Day Forecast for Marine Location Near Grantsville, MDHourly EDIT Help
Area Discussion for - Baltimore, MD/Washington  (on/off)  Help NOTE: mouseover dotted underlined text for definition
FXUS61 KLWX 061841 AFDLWX
Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 241 PM EDT Thu Aug 6 2020
A frontal boundary will remain stalled near the region through Friday. High pressure builds over our region this weekend before shifting offshore early next week.
NEAR TERM /THROUGH TONIGHT/.
Looking at surface obs this afternoon the stalled boundary looks to be located near the I-95 corridor. This boundary is looks to shift westward this afternoon but should remain mostly stalled over our region. Mesoanalysis shows that an axis of higher PW's is located east of the Blue Ridge Mountains with values above 1.9 inches and above 1.7 east of the Allegany front. A few showers and thunderstorms are currently on the radar but the coverage is expected to increase through this evening. A combination of the stalled boundary coupled with a shortwave moving through along with with good placement of the upper level jet will lead to environment conducive for scattered thunderstorms that have the potential to become severe. The main threat this evening will be the threat for heavy rain storms that have the potential to cause flash flooding and longer fused flood warnings.
The 12Z HREF has come in with more widespread coverage with a signal that areas in central Virginia especially east of I-81 and south of the DC metro. There is significant signs that southern Maryland and central Virginia will get a decent punch of rain and storms, but there are hints of a threat for northern Virginia and possibly parts of northern Virginia. A Flash Flood Watch has been issued to cover this threat. Models have been showing that the threat for heavy rain could continue into the early morning periods of Friday.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/.
The stationary boundary remains stalled over our region through Friday. Multiple upper level shortwaves are expected to move through our region with the main trough axis approaching from our west late Friday through early Saturday. The continued presences of the stalled boundary overhead along with multiple shortwaves and upper level jet will lead to a continue threat for severe weather and flash flooding. Both global and mesoscale models are showing an axis of precipitation moving through areas along and east of the Blue Ridge mountains. This area has already received a lot of rain from the tropical storm and will received additional rainfall this evening. The current Flash Flood Watch may need to be extended through tomorrow afternoon but I will punt that off to evening shift to make that decision. I again think that flooding threat will be the bigger concern but I can't rule out a few severe storms on Friday. The coverage of storms and showers should lessen by Friday evening and into the overnight periods.
The trough axis shifts through and east of our region by Saturday morning. A few lingers showers will be possible into early Saturday but weak high pressure tries to start building over our region by Saturday afternoon. Clearing skies and a weak easterly flow should allow temps to rise up into the mid to upper 80s on Saturday with lows in the 60s and lower 70s.
LONG TERM /SUNDAY THROUGH THURSDAY/.
Sunday through Wednesday will see a gradual warming, as upper level ridging very slowly builds into the region from the west. Our area will be right on the outer periphery of the upper ridge, so there will be a few week shortwave troughs through the middle of next week that pass nearby. Meanwhile, surface high pressure will be overhead Sunday, before moving offshore into the early portion of the week.
So, all that being said, think Sunday is the least active day in the long term period, with only a few diurnally driven showers/storms out over the higher elevations with the aid of the terrain circulation. As high pressure moves offshore, heat and humidity will gradually increase Monday through Wednesday, which will aid in thunderstorm development each day. This is a return to the pattern we saw for much of July, which favored thunderstorm formation off of the river/bay breezes and the terrain circulations over the higher elevations. While not anticipating any organized severe weather at this time, can't rule out a few stronger storms each day, aided by locally enhanced shear due to mesoscale boundaries.
In addition to showers and storms each day, heat and humidity will be on the increase, which will start to lead to some higher heat indices. Temperatures in the upper 80s to near 90 on Sunday will then climb into the mid 90s by Wednesday. This, paired with dew points rising into the mid 70s, could lead to some heat indices returning to the triple digits, particularly Tuesday/Wednesday.
AVIATION /19Z THURSDAY THROUGH TUESDAY/.
Showers and thunderstorms are expected at all terminals this evening and through the overnight periods. Showers and storms should taper off at all terminals after 8Z. Fog and low ceilings are likely for most terminals overnight as winds become light and dew points temps remain high. MVFR to IFR conditions are likely early Friday and morning but VFR conditions should return by the middle parts of Friday morning. Further showers and storms will be possible on Friday but the coverage should become more isolated by Friday evening.
MVFR to IFR conditions due to fog and low ceilings will be possible Saturday morning for all terminals as ground remains moist and winds are light. VFR conditions expected for the rest of the day Saturday.
Generally dry on Sunday across the area with light winds, as high pressure sits overhead. Low end chance for showers and storms on Sunday afternoon in peak heating, primarily towards MRB. This could lead to some brief restrictions, should one roll over the terminal, but think storms will be widely scattered to isolated in nature with high pressure overhead.
On Monday, thunderstorm chances begin to increase as a more warm and humid air mass builds in with southerly flow returning to the region. Winds will be light however. Conditions remain VFR generally, outside of thunderstorms.
A weak boundary will remain stalled near the region through Friday. Showers and thunderstorms will remain the main threat for the marine areas. After Friday no small craft issues are expected for Saturday.
High pressure overhead on Sunday will push offshore into Monday. Winds will generally be light both days, with a southerly flow developing into Monday. No long-fuse marine hazards expected during this time. However, showers and storms are possible each day, but especially on Monday afternoon and continuing into mid-week. These could produce wind gusts that necessitate SMWs.
Advancing warm front plus very moist and warm (unstable) air mass advecting north behind it plus shortwave energy aloft will likely result in periods of heavy rain with passing thunderstorms through this evening. Given antecedent conditions, a flash flood watch through early Friday is warranted for those locations which received significant rain earlier this week and areas where CAMS guidance is suggesting heavy rains are possible later today. As guidance is similarly wet for Friday, the watch may need to be extended.
LWX WATCHES/WARNINGS/ADVISORIES. DC . Flash Flood Watch through late tonight for DCZ001. MD . Flash Flood Watch through late tonight for MDZ003>006-011-013- 014-016>018-503>508. VA . Flash Flood Watch through late tonight for VAZ025>031-036>040- 050>057-501-502-505>508. WV . Flash Flood Watch through late tonight for WVZ051>053. MARINE . None.
SYNOPSIS . JMG NEAR TERM . JMG SHORT TERM . JMG LONG TERM . CJL AVIATION . CJL/JMG MARINE . CJL/JMG HYDROLOGY .
Weather Reporting StationsEDIT (on/off)  Help NOTE: Click on distance to see the station location on a map
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports. Follow links for more data.
|Garrett County Airport, MD||11 mi||52 min||ESE 6||10.00 mi||Fair||64°F||62°F||94%||1021.3 hPa|
|Cumberland, Greater Cumberland Regional Airport, WV||22 mi||52 min||N 0||10.00 mi||Overcast||74°F||68°F||81%||1020 hPa|
Link to 5 minute data for K2G4
Wind History from 2G4 (wind in knots)
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|2 days ago||SE||SE||SE||SE||SE||SE||S||SE||SE||SE||SE||Calm||W||W||W||W||W|
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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)(on/off)  Help
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