Marine Weather and Tide Forecast for Potomac Heights, MD
July 3, 2024 1:30 AM EDT (05:30 UTC) Change Location
![]() | Sunrise 5:47 AM Sunset 8:38 PM Moonrise 2:16 AM Moonset 6:01 PM |
ANZ535 Tidal Potomac From Key Bridge To Indian Head- 1034 Pm Edt Tue Jul 2 2024
Rest of tonight - S winds 5 kt. Waves less than 1 ft.
Wed - S winds 5 to 10 kt. Waves 1 ft.
Wed night - S winds 5 to 10 kt. Waves 1 ft.
Thu - SW winds 5 kt. Waves less than 1 ft. A chance of showers and tstms.
Thu night - SW winds 5 kt. Waves less than 1 ft. A chance of showers and tstms.
Fri - SW winds around 5 kt. Waves 1 ft. A chance of showers and tstms.
Fri night - S winds around 5 kt. Waves 1 ft. A chance of showers and tstms.
Sat - S winds around 5 kt. Waves 1 ft. Showers likely through the night. A chance of tstms. A chance of showers after midnight.
Sun - S winds around 5 kt. Waves 1 ft or less. A chance of showers and tstms through the night.
winds and waves higher and visibilities lower in and near tstms.
winds and waves higher and visibilities lower in and near tstms.
ANZ500 1034 Pm Edt Tue Jul 2 2024
Synopsis for the tidal potomac and md portion of the chesapeake bay -
strong high pressure continues its influence over the waters before slowly pushing off to the north and east off the new england coast tonight. Eventually, a warm front approaches from the west before passing to the north on Wednesday. A cold front nears the waters Friday into Saturday before stalling out early next week. Small craft advisories are possible for portions of the waters Wednesday afternoon into Wednesday night.
strong high pressure continues its influence over the waters before slowly pushing off to the north and east off the new england coast tonight. Eventually, a warm front approaches from the west before passing to the north on Wednesday. A cold front nears the waters Friday into Saturday before stalling out early next week. Small craft advisories are possible for portions of the waters Wednesday afternoon into Wednesday night.
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Area Discussion for - Baltimore, MD/Washington
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FXUS61 KLWX 030112 AFDLWX
Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 912 PM EDT Tue Jul 2 2024
SYNOPSIS
Dry conditions, seasonable temperatures, and low humidity look to continue through tomorrow as surface high pressure slowly pushes offshore. A frontal boundary will approach the area and stall to the northwest Thursday before crossing the region this weekend. Heat and humidity will return as a result for the Independence Day holiday along with increased chances for thunderstorms.
NEAR TERM /THROUGH WEDNESDAY/
No major changes to the previous forecast. Lowered Min T's a degree or two for most, especially the cooler locales west of the Blue Ridge
Previous discussion follows
Winds will turn to the southeast tonight as high pressure slowly shifts offshore. This will allow for a subtle uptick in moisture heading into Wednesday. Even with that said, enough dry air should remain to keep low temperatures in the upper 50s and low to mid 60s across the region.
Broad high pressure will continue off the New England/Mid- Atlantic coast Wednesday morning into Wednesday afternoon.
Moist southeast flow off the Atlantic will return as a result allowing for a subtle boost in humidity. Dry conditions are expected with mostly sunny to partly cloudy skies expected. High temperatures Wednesday will run a few degrees above normal with highs near 90 degrees east of the Alleghenies (low to mid 80s mountains). A mountain shower or thunderstorm cannot be ruled out ahead of the front Wednesday afternoon and evening.
SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/
High pressure continues offshore Wednesday night with a cold front entering in from the Ohio River Valley for the Independence Day holiday. Clouds will increase as result along with the influx of moisture across the region on southeasterly flow. Showers and thunderstorms remain possible Wednesday night especially west of the Allegheny Front. Most locations will remain dry with increasing humidity and cloud cover. Lows Wednesday night will hold steady in the mid to upper 60s and low 70s.
The real change comes Thursday as the subtropical ridge moves into the southeastern U.S. This will allow for the return of excessive heat and humidity along with increased chances for strong thunderstorms. A pre-frontal shortwave trough combined with an approaching cold front from the Ohio River Valley will lead to scattered to numerous showers and thunderstorms across the area Thursday afternoon into Thursday evening. Current hi-res CAM guidance and synoptic models also illustrate this notion with a front slowly pushing eastward into the mountains before stalling over the area and even retreating back to the north heading into Friday. With that said, uncertainty remains in regards to the coverage of thunderstorm activity for Independence Day festivities including fireworks Thursday evening into Thursday night.
High temperatures Thursday will range from the upper 70s and low 80s over the higher elevations west of the Blue Ridge with low to mid 90s further east. Heat index values east of the Alleghenies will run anywhere between 98-104 degrees. Higher elevations will see heat index values in the upper 80s and mid 90s Thursday afternoon. These temperatures combined with increased humidity will harbor ample instability for storms to feed off of Thursday afternoon and evening. CAPE values will be on the order of 1500-2500 j/kg with 0- 6km shear values less than 35 kts. Lapse rates will also remain poor less than 6.5 C/km. Precipitable water values seem to be the bigger concern here as the atmosphere becomes juiced with values in excess of 2-2.5 inches across majority of the forecast region. As a result expect a mix of pulse to multi-cell clusters of storms propagating east Thursday afternoon and evening. Primary threats with storms are locally damaging winds and isolated instances of urban flooding. Once again confidence is lower pending increasing cloud cover and the overall placement/timing of the cold front/prefrontal shortwave trough. Overnight low temperatures Thursday will be in the low to mid 70s for most locations.
LONG TERM /FRIDAY THROUGH TUESDAY/
A rather persistent longwave pattern will remain in place through the long term period of the forecast. During that time, broad longwave troughing will reside over the center of the country, with ridging in place along the West Coast, as well as in the North Atlantic. Through the period, multiple shortwave disturbances will round the base of the trough and pass off to our northwest in southwesterly flow aloft. At the surface, high pressure will remain in place offshore, leading to southerly flow. Southerly flow will maintain a warm and very humid airmass over the area, leading to daily chances for thunderstorms.
On Friday we'll be somewhat displaced from stronger forcing for ascent off to our west, with heights holding near neutral within southwesterly flow aloft. As a result, coverage of storms may be lower compared to surrounding days. Nonetheless, thunderstorms should form during the afternoon in response to daytime heating.
Storms should continue through the evening before dissipating during the first half of the overnight with loss of daytime heating.
A potent shortwave and associated surface low/trailing cold front will track through the Ohio Valley and Eastern Great Lakes on Saturday. This system will provide stronger large scale forcing for ascent, leading to a higher coverage of storms on Saturday.
Increasing flow aloft (30-40 knots of mid-level flow) will overlap with deep moisture (PWATs well over 2 inches) and ample instability (MLCAPE values well in excess of 1000 J/kg) to create an environment that is favorable for both severe thunderstorms and flash flooding.
However, antecedent dry conditions should limit the flood threat outside of urban areas.
The system's cold front will move through Saturday night, potentially allowing a slightly cooler and less humid airmass to move in for Sunday. An overall lower coverage of storms is expected Sunday, with the activity primarily focused across southeastern portions of the forecast area.
Most guidance shows deeper moisture (PWATs in excess of 2 inches)
being drawn northward into the area again on Monday. Afternoon thunderstorms will be possible once again, along with the potential for localized downbursts and isolated instances of flooding.
It will be hot and humid through much of the long term period, especially on Friday and Saturday. Heat indices may potentially exceed 100 degrees on both Friday and Saturday.
AVIATION /01Z WEDNESDAY THROUGH SUNDAY/
Prevailing VFR conditions are expected through Wednesday night as high pressure slowly pushes offshore. Stratocumulus is expected to continue this afternoon and evening with clearing overnight. An additional period of stratocumulus is likely at all terminals from early Wednesday morning through Wednesday afternoon. SCT-BKN cloud bases will run 060-080 kft. Winds will remain light out of the south and southeast through Wednesday morning. Intermittent gusts up to 15 kts are possible at terminals mainly north of I-66/US-50 Wednesday afternoon.
Sub-VFR conditions return Thursday afternoon and evening as a prefrontal trough and front enter the region. Scattered to numerous strong to severe thunderstorms look to pose an impact to the terminals during this time. The primary threats include gusty winds, small hail, heavy rainfall, and frequent lightning. Thunderstorm activity will diminish late Thursday night into Friday morning.
Winds will start out of the southwest Thursday morning before switching to the west Thursday afternoon and evening.
Prevailing VFR conditions are expected on both Friday and Saturday, but temporary drops to sub-VFR conditions may be possible in thunderstorms either afternoon or evening. Winds will generally be light out of the south.
MARINE
Quiet conditions are expected across the waters this afternoon as high pressure pivots overhead. Winds will turn to the south and southeast while remaining below SCA levels. Some channeling may occur over the northern and middle part of the bay later this evening and into tonight. Additional channeling is possible Wednesday afternoon and evening as the wind changes to the south. Have issued an SCA for the open waters during this time.
On Thursday, winds remain out of the south/southeast with SCA criteria gusts possible in the southern portions of the waters.
SMWs may be needed during showers and thunderstorms that afternoon.
Sub-SCA level southerly winds are expected over the waters on both Friday and Saturday. Thunderstorms may also be possible either afternoon or evening.
TIDES/COASTAL FLOODING
Tidal anomalies are forecast to steadily rise through the week as southeast to south winds prevail. Some sensitive locations will reach Action Stage, and Annapolis is the most likely to go into minor flooding Wednesday morning. Additional periods of coastal flooding are possible during the morning high tide Thursday and Friday.
LWX WATCHES/WARNINGS/ADVISORIES
DC...None.
MD...Small Craft Advisory from 5 PM Wednesday to 2 AM EDT Thursday for MDZ008.
VA...None.
WV...None.
MARINE...Small Craft Advisory from 5 PM Wednesday to 2 AM EDT Thursday for ANZ530>534-537>543.
Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 912 PM EDT Tue Jul 2 2024
SYNOPSIS
Dry conditions, seasonable temperatures, and low humidity look to continue through tomorrow as surface high pressure slowly pushes offshore. A frontal boundary will approach the area and stall to the northwest Thursday before crossing the region this weekend. Heat and humidity will return as a result for the Independence Day holiday along with increased chances for thunderstorms.
NEAR TERM /THROUGH WEDNESDAY/
No major changes to the previous forecast. Lowered Min T's a degree or two for most, especially the cooler locales west of the Blue Ridge
Previous discussion follows
Winds will turn to the southeast tonight as high pressure slowly shifts offshore. This will allow for a subtle uptick in moisture heading into Wednesday. Even with that said, enough dry air should remain to keep low temperatures in the upper 50s and low to mid 60s across the region.
Broad high pressure will continue off the New England/Mid- Atlantic coast Wednesday morning into Wednesday afternoon.
Moist southeast flow off the Atlantic will return as a result allowing for a subtle boost in humidity. Dry conditions are expected with mostly sunny to partly cloudy skies expected. High temperatures Wednesday will run a few degrees above normal with highs near 90 degrees east of the Alleghenies (low to mid 80s mountains). A mountain shower or thunderstorm cannot be ruled out ahead of the front Wednesday afternoon and evening.
SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/
High pressure continues offshore Wednesday night with a cold front entering in from the Ohio River Valley for the Independence Day holiday. Clouds will increase as result along with the influx of moisture across the region on southeasterly flow. Showers and thunderstorms remain possible Wednesday night especially west of the Allegheny Front. Most locations will remain dry with increasing humidity and cloud cover. Lows Wednesday night will hold steady in the mid to upper 60s and low 70s.
The real change comes Thursday as the subtropical ridge moves into the southeastern U.S. This will allow for the return of excessive heat and humidity along with increased chances for strong thunderstorms. A pre-frontal shortwave trough combined with an approaching cold front from the Ohio River Valley will lead to scattered to numerous showers and thunderstorms across the area Thursday afternoon into Thursday evening. Current hi-res CAM guidance and synoptic models also illustrate this notion with a front slowly pushing eastward into the mountains before stalling over the area and even retreating back to the north heading into Friday. With that said, uncertainty remains in regards to the coverage of thunderstorm activity for Independence Day festivities including fireworks Thursday evening into Thursday night.
High temperatures Thursday will range from the upper 70s and low 80s over the higher elevations west of the Blue Ridge with low to mid 90s further east. Heat index values east of the Alleghenies will run anywhere between 98-104 degrees. Higher elevations will see heat index values in the upper 80s and mid 90s Thursday afternoon. These temperatures combined with increased humidity will harbor ample instability for storms to feed off of Thursday afternoon and evening. CAPE values will be on the order of 1500-2500 j/kg with 0- 6km shear values less than 35 kts. Lapse rates will also remain poor less than 6.5 C/km. Precipitable water values seem to be the bigger concern here as the atmosphere becomes juiced with values in excess of 2-2.5 inches across majority of the forecast region. As a result expect a mix of pulse to multi-cell clusters of storms propagating east Thursday afternoon and evening. Primary threats with storms are locally damaging winds and isolated instances of urban flooding. Once again confidence is lower pending increasing cloud cover and the overall placement/timing of the cold front/prefrontal shortwave trough. Overnight low temperatures Thursday will be in the low to mid 70s for most locations.
LONG TERM /FRIDAY THROUGH TUESDAY/
A rather persistent longwave pattern will remain in place through the long term period of the forecast. During that time, broad longwave troughing will reside over the center of the country, with ridging in place along the West Coast, as well as in the North Atlantic. Through the period, multiple shortwave disturbances will round the base of the trough and pass off to our northwest in southwesterly flow aloft. At the surface, high pressure will remain in place offshore, leading to southerly flow. Southerly flow will maintain a warm and very humid airmass over the area, leading to daily chances for thunderstorms.
On Friday we'll be somewhat displaced from stronger forcing for ascent off to our west, with heights holding near neutral within southwesterly flow aloft. As a result, coverage of storms may be lower compared to surrounding days. Nonetheless, thunderstorms should form during the afternoon in response to daytime heating.
Storms should continue through the evening before dissipating during the first half of the overnight with loss of daytime heating.
A potent shortwave and associated surface low/trailing cold front will track through the Ohio Valley and Eastern Great Lakes on Saturday. This system will provide stronger large scale forcing for ascent, leading to a higher coverage of storms on Saturday.
Increasing flow aloft (30-40 knots of mid-level flow) will overlap with deep moisture (PWATs well over 2 inches) and ample instability (MLCAPE values well in excess of 1000 J/kg) to create an environment that is favorable for both severe thunderstorms and flash flooding.
However, antecedent dry conditions should limit the flood threat outside of urban areas.
The system's cold front will move through Saturday night, potentially allowing a slightly cooler and less humid airmass to move in for Sunday. An overall lower coverage of storms is expected Sunday, with the activity primarily focused across southeastern portions of the forecast area.
Most guidance shows deeper moisture (PWATs in excess of 2 inches)
being drawn northward into the area again on Monday. Afternoon thunderstorms will be possible once again, along with the potential for localized downbursts and isolated instances of flooding.
It will be hot and humid through much of the long term period, especially on Friday and Saturday. Heat indices may potentially exceed 100 degrees on both Friday and Saturday.
AVIATION /01Z WEDNESDAY THROUGH SUNDAY/
Prevailing VFR conditions are expected through Wednesday night as high pressure slowly pushes offshore. Stratocumulus is expected to continue this afternoon and evening with clearing overnight. An additional period of stratocumulus is likely at all terminals from early Wednesday morning through Wednesday afternoon. SCT-BKN cloud bases will run 060-080 kft. Winds will remain light out of the south and southeast through Wednesday morning. Intermittent gusts up to 15 kts are possible at terminals mainly north of I-66/US-50 Wednesday afternoon.
Sub-VFR conditions return Thursday afternoon and evening as a prefrontal trough and front enter the region. Scattered to numerous strong to severe thunderstorms look to pose an impact to the terminals during this time. The primary threats include gusty winds, small hail, heavy rainfall, and frequent lightning. Thunderstorm activity will diminish late Thursday night into Friday morning.
Winds will start out of the southwest Thursday morning before switching to the west Thursday afternoon and evening.
Prevailing VFR conditions are expected on both Friday and Saturday, but temporary drops to sub-VFR conditions may be possible in thunderstorms either afternoon or evening. Winds will generally be light out of the south.
MARINE
Quiet conditions are expected across the waters this afternoon as high pressure pivots overhead. Winds will turn to the south and southeast while remaining below SCA levels. Some channeling may occur over the northern and middle part of the bay later this evening and into tonight. Additional channeling is possible Wednesday afternoon and evening as the wind changes to the south. Have issued an SCA for the open waters during this time.
On Thursday, winds remain out of the south/southeast with SCA criteria gusts possible in the southern portions of the waters.
SMWs may be needed during showers and thunderstorms that afternoon.
Sub-SCA level southerly winds are expected over the waters on both Friday and Saturday. Thunderstorms may also be possible either afternoon or evening.
TIDES/COASTAL FLOODING
Tidal anomalies are forecast to steadily rise through the week as southeast to south winds prevail. Some sensitive locations will reach Action Stage, and Annapolis is the most likely to go into minor flooding Wednesday morning. Additional periods of coastal flooding are possible during the morning high tide Thursday and Friday.
LWX WATCHES/WARNINGS/ADVISORIES
DC...None.
MD...Small Craft Advisory from 5 PM Wednesday to 2 AM EDT Thursday for MDZ008.
VA...None.
WV...None.
MARINE...Small Craft Advisory from 5 PM Wednesday to 2 AM EDT Thursday for ANZ530>534-537>543.
toggle option: (graph/table)
Airport Reports
EDIT HIDE  Help Click EDIT to display multiple airports. Follow links for more data.Airport | Dist | Age | Wind kt | Vis | Sky | Weather | Air | DewPt | RH | inHg |
KNYG QUANTICO MCAF /TURNER FIELD,VA | 13 sm | 34 min | SSE 08 | 8 sm | Partly Cloudy | 73°F | 64°F | 73% | 30.23 | |
KDCA RONALD REAGAN WASHINGTON NATIONAL,VA | 17 sm | 38 min | S 08 | 10 sm | A Few Clouds | 73°F | 63°F | 69% | 30.22 | |
KHEF MANASSAS RGNL/HARRY P DAVIS FIELD,VA | 22 sm | 34 min | SSE 06 | 10 sm | Overcast | 70°F | 63°F | 78% | 30.22 | |
KRMN STAFFORD RGNL,VA | 23 sm | 15 min | SE 04 | 10 sm | Mostly Cloudy | 70°F | 59°F | 69% | 30.23 |
Link to 1 hour of 5 minute data for KDAA
Terminal Aerodrome Forecast (TAF) for KDAA
toggle option: (graph/table)
Terminal Aerodrome Forecast (TAF) for KDAA
Wind History graph: DAA
(wind in knots)Glymont
Click for Map
Tue -- 02:35 AM EDT Moonrise
Tue -- 04:39 AM EDT 2.24 feet High Tide
Tue -- 05:48 AM EDT Sunrise
Tue -- 11:41 AM EDT 0.15 feet Low Tide
Tue -- 05:16 PM EDT 1.79 feet High Tide
Tue -- 05:50 PM EDT Moonset
Tue -- 08:36 PM EDT Sunset
Tue -- 11:28 PM EDT 0.20 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Click for Map
Tue -- 02:35 AM EDT Moonrise
Tue -- 04:39 AM EDT 2.24 feet High Tide
Tue -- 05:48 AM EDT Sunrise
Tue -- 11:41 AM EDT 0.15 feet Low Tide
Tue -- 05:16 PM EDT 1.79 feet High Tide
Tue -- 05:50 PM EDT Moonset
Tue -- 08:36 PM EDT Sunset
Tue -- 11:28 PM EDT 0.20 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Glymont, Maryland, Tide feet
12 am |
0.5 |
1 am |
1 |
2 am |
1.5 |
3 am |
2 |
4 am |
2.2 |
5 am |
2.2 |
6 am |
2 |
7 am |
1.6 |
8 am |
1.2 |
9 am |
0.8 |
10 am |
0.5 |
11 am |
0.2 |
12 pm |
0.2 |
1 pm |
0.4 |
2 pm |
0.8 |
3 pm |
1.3 |
4 pm |
1.6 |
5 pm |
1.8 |
6 pm |
1.7 |
7 pm |
1.4 |
8 pm |
1 |
9 pm |
0.7 |
10 pm |
0.4 |
11 pm |
0.2 |
Deep Point
Click for Map
Tue -- 02:35 AM EDT Moonrise
Tue -- 04:14 AM EDT 2.00 feet High Tide
Tue -- 05:49 AM EDT Sunrise
Tue -- 11:16 AM EDT 0.14 feet Low Tide
Tue -- 04:51 PM EDT 1.59 feet High Tide
Tue -- 05:50 PM EDT Moonset
Tue -- 08:36 PM EDT Sunset
Tue -- 11:03 PM EDT 0.18 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Click for Map
Tue -- 02:35 AM EDT Moonrise
Tue -- 04:14 AM EDT 2.00 feet High Tide
Tue -- 05:49 AM EDT Sunrise
Tue -- 11:16 AM EDT 0.14 feet Low Tide
Tue -- 04:51 PM EDT 1.59 feet High Tide
Tue -- 05:50 PM EDT Moonset
Tue -- 08:36 PM EDT Sunset
Tue -- 11:03 PM EDT 0.18 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Deep Point, Mattawoman Creek, Maryland, Tide feet
12 am |
0.6 |
1 am |
1.1 |
2 am |
1.5 |
3 am |
1.9 |
4 am |
2 |
5 am |
1.9 |
6 am |
1.7 |
7 am |
1.3 |
8 am |
0.9 |
9 am |
0.6 |
10 am |
0.3 |
11 am |
0.2 |
12 pm |
0.2 |
1 pm |
0.5 |
2 pm |
0.9 |
3 pm |
1.3 |
4 pm |
1.5 |
5 pm |
1.6 |
6 pm |
1.4 |
7 pm |
1.1 |
8 pm |
0.8 |
9 pm |
0.5 |
10 pm |
0.3 |
11 pm |
0.2 |
Sterling, VA,
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