Marine Weather and Tide Forecast for Shady Side, MD

NEAR TERM /THROUGH TONIGHT/
Two main topics to get through the overnight - heavy rain and smoke.

Heavy rain - Have trimmed the flood watch in the northern and southwestern portions of previous watch to focus on corridor of convergence with the highest threat through the rest of the evening. High instantaneous rates could result in flash flooding across portions of central VA into northern VA and southern MD through the first part of the night. Elsewhere, a few showers or a thunderstorm are possible with brief heavy rain.

Smoke - The easterly flow has brought in smoke from NJ to the sfc from the DC metro northward into northeast MD. This is resulting in code orange to red air quality being observed.
Those with sensitive.

The cloudcover overnight will keep temperatures in the mid to upper 60s for most.



SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/
Not much of a change in the forecast as a pesky stalled front remains nearby. The good news is that Sunday appears drier although cloud cover will remain due in part to onshore easterly flow from strengthening high pressure off the New England coast. This high pressure system looks to force the frontal boundary further south into central and southwest VA Sunday morning into SUnday midday. Subsidence behind shortwave low pressure from Saturday evening will also promote a decrease in PoPs as well for at least 2/3rds of the forecast region. Even with that said, the risk for showers and thunderstorms will still remain from the far western portions of the Alleghenies south and east into central and eastern VA. This lines up with both 00z CAM and synoptic guidance very well with the front subdued to the south as jet max energy squirts east and high pressure wedges in from the north. Once again, flash flooding will be the primary concern with any showers and thunderstorms that develop given the antecedent conditions. Locally damaging winds cannot be ruled out as well with SPC maintains a Day 2 Marginal Risk for portions of the VA Piedmont mainly along and south of I-64. Highs Sunday will push into the upper 60s and low 70s with easterly flow on the sable side of the boundary.
LOcations along and south of I-64 will sit in the mid to upper 70s to around 80 degrees.

The boundary works slowly back to the north Monday bringing continued chances for showers and thunderstorms. Severe weather does not appear to be an issue as stable marine air will be slow to erode over the region. Highs Monday will remain in the upper 60s and low to mid 70s with the influence of high pressure along the New ENgland coast still wedging south and the front slowly push back north from central and southern VA. Overall coverage of showers and thunderstorms will be scattered with a focus mainly south and east of metro areas. Convection chances increase again Tuesday as warmer air works back into the region.

LONG TERM /TUESDAY THROUGH SATURDAY/
The surface boundary over the area finally starts to dissipate and lift north of the area come Tuesday, with a weak upper trough approaching from the Ohio Valley. Showers and thunderstorms are expected to form during the afternoon hours within a very humid airmass (surface dewpoints around 70). High temperatures on Tuesday are expected to be reach into the upper 70s and lower 80s for most.

High pressure strengthens offshore moving into the middle of the week, leading to south to southwesterly low-level flow and increasing heat and humidity locally. Temperatures should reach into the 90s on both Wednesday and Thursday. When combined with dewpoints in the lower 70s, heat indices may approach 100 on Thursday.
Thunderstorms appear possible both days, but the greater coverage should be on Thursday as an upper trough tracks off to our north across the Great Lakes, with its associated cold front approaching from the west. Current model guidance suggests that ample instability and shear may be present on Thursday, so some storms may be on the stronger side. Upper troughing is expected to dig in from the Great Lakes on Friday. Cooler and drier conditions are expected locally in the wake of the system's cold front.

AVIATION /02Z SUNDAY THROUGH THURSDAY/
Once the thunderstorms and showers exit our region, IFR ceilings are likely to build over all terminals with MVFR visibilities due to drizzle.

Additional periods of sub-VFR conditions are likely to continue for both Sunday and Monday. Shower and thunderstorm chances will remain during the afternoon and evening hours especially at terminals south and east of KCHO. Areas further north will remain in a marine airmass with persistent low clouds and areas of fog/low clouds during the overnight/early morning periods.

Sub-VFR conditions may be possible Tuesday morning, but improvement back to prevailing VFR conditions is expected Tuesday afternoon through Wednesday. Showers and thunderstorms are forecast to develop each afternoon/evening, and these could result in brief sub-VFR conditions if they move over a terminal.

MARINE
A stalled front will remain draped across the waters through tis evening. Winds continue out of the north and east tonight. Shower and thunderstorm chances are expected once again later this evening (mainly after 20z/4pm). Some storms may warrant Special Marine Warnings with gusty winds and locally heavy rainfall as the primary concerns. Low clouds will continue overnight, and fog may form as well. Less shower and thunderstorm activity can be expected Sunday and Monday. Winds will remain out of the east on both days at less than 15 kts.

Winds are forecast to remain below SCA levels through the middle of the week. Daily afternoon showers and thunderstorms could pose a threat to mariners from gusty winds and lightning strikes.

LWX WATCHES/WARNINGS/ADVISORIES
DC...Air Quality Alert until midnight EDT tonight for DCZ001.
Flood Watch until 11 PM EDT this evening for DCZ001.
MD...Air Quality Alert until midnight EDT tonight for MDZ006-008- 011-014-507-508.
Flood Watch until 11 PM EDT this evening for MDZ013-016>018- 503-504.
VA...Flood Watch until 11 PM EDT this evening for VAZ027>031- 038>040-050-051-053>057-501-502-505>507-526-527.
WV...Flood Watch until 11 PM EDT this evening for WVZ053.
MARINE...Air Quality Alert until midnight EDT tonight for ANZ530.