
Tidal Potomac from Key Bridge to Indian Head MD Marine Forecast
Rest Of The Overnight...N Winds 5 Kt. Waves Less Than 1 Ft. A Slight Chance Of Rain. |
Today...N Winds 5 Kt...Becoming Sw Late. Waves 1 Ft. |
Tonight...Sw Winds 5 To 10 Kt...Becoming Nw 10 To 15 Kt With Gusts To 20 Kt After Midnight. Waves 1 Ft. |
Thu...Nw Winds 5 To 10 Kt With Gusts To 20 Kt. Waves 1 Ft. |
Thu Night...Se Winds Around 5 Kt. Waves 1 Ft. |
Fri...S Winds 5 To 10 Kt...Increasing To 15 Kt In The Afternoon. Gusts Up To 25 Kt. Waves 1 To 2 Ft. |
Fri Night...S Winds 15 To 20 Kt With Gusts To 30 Kt. Waves 2 Ft. Showers. |
Sat...Sw Winds 20 To 25 Kt...Becoming Nw. Waves 2 Ft. Showers Through The Day. |
Sun...Nw Winds 10 To 15 Kt...Becoming Ne 5 To 10 Kt In The Evening, Then Becoming S After Midnight. Waves 1 Ft. |
Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 342am EDT Wednesday Mar 29 2023 Synopsis High pressure briefly builds over the area today, followed by a weak cold front moving through tonight. Freezing temperatures are likely across a large part of the area tonight. High pressure returns on Thursday. A strong area of low pressure impacts the region Friday into Saturday night, bringing widespread rainfall and high winds. Near Term - Through Tonight The departing wave of low pressure to our south continues to produce light rain across Central VA, with drizzle observed as far north as Leesburg and DC. The light rain should come to an end by sunrise. A Frost Advisory is in effect until 8AM for the central Shenandoah Valley where light winds, surface moisture from earlier rain, and clear skies should allow the atmosphere to decouple in the hours just before sunrise. Dry conditions are forecast for today as highs reach the mid 50s to around 60F, except mid 40s in the Alleghenies. Abundant sunshine this morning will turn to a mix of sun and clouds as high cirrus moves overhead this afternoon. A cold front is forecast to move across PA this afternoon, reaching north/western MD and the Potomac Highlands late this evening. Isolated to scattered showers will transition to snow showers along the Allegheny Front as cold air quickly advects in. Total snow accumulations less than 0.5" for most locations, with locally higher amounts up to 1.5" possible in parts of Garrett and Grant Counties. Most of the precipitation comes to an end after midnight, though some snow could linger through the overnight at the highest elevations. The cold air is expected to drop temperatures below freezing along and west of the Blue Ridge and in north-central/northeast MD, with mid to upper 30s into southern MD/central VA. A Freeze Warning goes into effect at 4AM Thursday morning for areas where the growing season has already begun, including parts of the Shenandoah Valley, eastern foothills of the Blue Ridge, and western areas of Loudoun, Montgomery, and Howard Counties. Short Term - Thursday Through Friday Night High pressure builds over the region Thursday, keeping conditions dry with slightly cooler temperatures as highs only reach the upper 40s to upper 50s. Thursday night lows drop to the 30s areawide, with frost possible west of the I-95 corridor. A warm front lifts north through the area Friday morning as a strong area of low pressure approaches from the west. A few showers will be possible as the area enters the warm sector Friday morning, then rain overspread the area from west to east by late Friday evening. Strong WAA (Warm Air Advection - the movement of warm air) easily overcomes the any cooling effects from clouds and rain, pushing highs into the mid 60s to around 70F. Breezy conditions quickly develop by Friday afternoon as light east winds shift south, then southwest and increase to around 15-20mph with gusts up to 25mph. Winds continue to increase Friday night as as a large upper trough and associated surface cold front move through our area. Model guidance over the last couple of days continues to indicate the potential for high winds developing late Friday night into Saturday across the entire area, especially in the mountains. By sunrise Saturday, sustained southwest winds could be around 20-25mph with gusts up to 35-40mph (up to 45-50mph in the mountains). The strongest winds arrive Saturday. Continue to monitor the forecast in the coming days. Long Term - Saturday Through Tuesday A cold front will move across the region Saturday and push rain shower activity into the eastern half of the region, mainly along and east of I-95. We can't rule out a few thunderstorms that could cause wind damage. There will be a lot of wind at all levels of the atmosphere associated with the strong cold front and its mother low in the Great Lakes region Saturday and Saturday night. Winds will be gusty out of the southwest ahead of the cold front and become even more gusty along the front and right behind frontal passage sometime Saturday afternoon. We could easily see sustained southwest winds of 20 to 30 mph with frequent gusts of 40 to 45 mph in a lot of locations. After frontal passage later Saturday afternoon, strong winds will slowly diminish out of the west-northwest to northwest but we could still see gusts of 35 mph as late as midnight Saturday night. A few upslope rain or snow showers possible in the northern Alleghenies. Temperatures will reach the lower to middle 70s on Saturday ahead of the front. Expect temperatures will cool off rapidly Saturday evening through Sunday morning, but should rebound nicely Sunday afternoon with ample sunshine and some downslope component to the wind. Highs Sunday could be 15 to 20 degrees cooler than Saturday but should still be near average for early April. Dry and seasonable conditions will linger into early Monday. Then once the winds shift around from the northwest to the south, moisture will come back into the picture ahead of the next low pressure system. Some rain showers could develop Monday afternoon and Monday night. Highs will also rebound into the 60s to near 70. A low pressure system could scoot by to our south on Tuesday into Tuesday night. Additional rain showers possible with this low. Timing and coverage is uncertain as the front that brought a chance for rain showers later Monday could stall to our south. Marine Favorable marine conditions continue through early this evening, then sub-SCA (Small Craft Advisory) conditions develop tonight into Thursday morning as northwest winds increase behind a passing cold front. Sub-SCA (Small Craft Advisory) conditions return Thursday as high pressure builds over the region. A strong area of low pressure approaches the area on Friday, and a warm front lifts north through the waters Friday morning. Along with widespread rainfall, sub-SCA (Small Craft Advisory) conditions are likely to develop by sunrise Friday morning and continue into Friday night. Gales are likely to develop late Friday night across all the waters. Gales likely Saturday and Saturday night. Small craft advisories likely Sunday. No marine hazards Sunday night. Winds southwest shifting northwest 20 to 25 knots gusts 30 to 40 knots possible Saturday and Saturday night. Winds northwest 15 to 25 knots gusts 30 knots Sunday, becoming southeast 10 to 15 knots Sunday night. Fire Weather High pressure is builds across the region today and Thursday, with a weak, mostly dry cold front crossing the area tonight. Temperatures are forecast to remain near to slightly below normal, with highs today in the mid to upper 50s and low 60s, and cooler on Thursday with mostly 50s. West winds today with gusts between 10-15KT for most outside the mountains where gusts of 20-25KT expected along the ridges. Lighter northwest winds for Thursday around 10-15KT. Seasonal temperatures combined with the high sun angle will yield minimum RH values between 20-30 percent today, and between 18-25pct Thursday afternoon. The next chance for wetting rain arrives Friday into Saturday. NOAA Baltimore MD/Washington DC Office: Watches - Warnings - Advisories DC...None. MD...Freeze Warning from 5am to 9am EDT Thursday for MDZ503-505. VA...Freeze Warning from 5am to 9am EDT Thursday for VAZ027>031- 040-501-505. Frost Advisory until 9am EDT this morning for VAZ025>027-029. WV...None. Marine Small Craft Advisory from 11pm this evening to 1pm EDT Thursday for ANZ530>543. Gale Watch from late Friday night through Saturday evening for ANZ530>543. |