Marine Weather and Tide Forecast for St. Michaels, MD

NEAR TERM /THROUGH TONIGHT/
A warm and breezy afternoon is expected well ahead of a cold front late tonight. Temperatures have already warmed well into the 70s as of 12:30 PM with increasing SSW winds.

The axis of a mid level ridge is forecast to crest across our area through this morning before shifting to our east and south this afternoon into tonight. This will take the center of surface high pressure farther southeast of our area. A tightening pressure gradient will develop across our area through this afternoon between high pressure to our southeast and well ahead of a cold front. As the boundary layer warms through the morning, strengthening winds above the surface will mix down to the surface and this will result in a gusty south to southwest wind. As the winds increase later this morning and peak during the afternoon, sustained winds of 15-20 mph are forecast with gusts up to 30 mph. The strongest winds may occur from about the I-95 corridor on south and east where some deeper mixing occurs. Some high level cloudiness will be cresting the ridge axis today, and it is possible that some cumulus clouds develop this afternoon pending convective temperatures being reached.

The strengthening southwesterly flow will boost the low-level warm air advection today and this evening ahead of a cold front.
This will result in temperatures well above average, with highs in the upper 70s to low 80s (cooler in the higher elevations).
Given a south to southwest wind, it will be cooler along much of the coastal areas. Along with the warm air advection, moisture advection will get underway as well through the day. This will bring an increase in the surface dew points, although with deeper mixing through the afternoon some lowering of the dew points should occur especially across much of New Jersey and Delaware.

As we go through tonight, a mild night for the region ahead of a cold front although the cold front will be working its way across parts of the region overnight. An upper-level trough will pivot across the eastern Great Lakes and adjacent Canada, however the main forcing looks to track to our north. A cold front tied to this feature though will arrive in our area. A line of showers and thunderstorms or even a few clusters are expected to develop this afternoon with or ahead of the cold front well to our west. The timing into our area is not ideal as any convection does not look to arrive into our far western zones until this evening.

The model forecast soundings indicate an increase in shear as a low-level jet increases ahead of the cold front, however the instability is on the lower side. Given diminishing forcing with time, the organized convection well to our west looks to be weakening quite a bit as it approaches and moves into our far western zones. If the convection remains organized enough and therefore does not weaken as quickly, then there is some potential for locally strong/damaging winds across the Poconos to perhaps parts of the Lehigh Valley and Berks County. This is mostly due to lingering dry air in the boundary layer and even some mid level dry air that could accelerate downward momentum within a downdraft. The SPC continues with a Marginal Risk (level 1 out of 5) for possible severe thunderstorms across the Poconos to parts of the Lehigh Valley and Berks County. The gradient surface winds will also settle down some tonight as the deeper mixing wanes after sunset. Low temperatures are forecast to be in the mid 50s to mid 60s.

SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/
Cold front will be continuing to sink south as Wednesday begins. There remains a bit of uncertainty in how quickly the front will be south of the region. If it doesn't get southeast of SE NJ and S DE until closer to mid day, than highs on Wednesday in Delmarva and the coastal plain of NJ will be close to if not a few degrees warmer than Tuesday.

High pressure will then be the dominant feature through Thursday. Even with the cold front, day time temperatures are expected to be up to 5 degrees warmer than normal.

The warm front associated with the next low pressure system could arrive as early as late Thursday, bringing the next chance for showers and storms.

LONG TERM /FRIDAY THROUGH MONDAY/
Warm front will continue to lift north through the region on Friday. Showers and thunderstorms become more likely Friday into Friday night as the warm front will be followed close behind by a cold front. Still lots of uncertainty about intensity, but we'll be watching any severe weather risk closely.

Some of the latest guidance is a bit slower with the cold front, depicting it crossing through the region during the day on Saturday. Consequently, there is high uncertainty in the precipitation chances and temperatures on Saturday. However, by Sunday into Monday, expect temperatures to be slightly below normal

AVIATION /18Z TUESDAY THROUGH SUNDAY/
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas.

Today...VFR. South to southwest winds around 15 knots with gusts up to 25 knots. High confidence.

Tonight...VFR overall with an increase in mainly mid to high level clouds. Some showers or a thunderstorm cannot be ruled out especially around KABE and KRDG, and given chances look low enough just included a VCSH there for now. Southwest winds near 10-15 knots and becoming northwest by 12Z. Low confidence on timing/coverage of any showers and thunder, especially with an eastward extent. High confidence on prevailing VFR and winds.

Outlook...

Wednesday into Thursday...VFR expected.

Thursday night through Saturday...periods of MVFR and even IFR with showers and thunderstorms possible.

MARINE
Small Craft Advisory conditions are forecast to develop this afternoon as southwesterly winds increase with gusts 25-30 knots on the ocean zones. This will continue most of tonight. It may take some time however for the stronger winds to reach the surface given much warmer air moving over the cool ocean water (water temperatures mostly in the 50s). Seas will also build in response to the period of stronger winds. For Delaware Bay, opted to issue a Small Craft Advisory for this afternoon into early this evening as gusts to around 25 knots are anticipated to occur especially closer to the coast.

Outlook...

Wednesday through Thursday night...Once seas subside below 5 ft Wednesday morning, winds and seas should stay below SCA criteria.

Friday...Southerly winds above 25 kt and seas above 5 ft are possible.

Saturday...Winds and seas are forecast to remain below SCA criteria.

FIRE WEATHER
For today, while the dewpoints will be much higher than yesterday, they will remain low enough and when combined with very warm temperatures this afternoon will result in the relative humidity dropping to mostly between 25 and 35 percent across most of New Jersey and Delaware. The relative humidity looks to stay higher in most of eastern Pennsylvania and Marylands Eastern Shore. In addition, south to southwest winds will increase to 15-20 mph with gusts up to 30 mph. The strongest winds may end up being from about I-95 south and east.
Based on the latest forecast and earlier coordination with State Fire partners, a Special Weather Statement has been issued for most of New Jersey and all of Delaware to cover the elevated risk of rapid fire spread this afternoon.

For Wednesday, minimum relative humidity will range from around 20 to 30 percent with temperatures mostly in the 70s. Northwest winds 10-15 mph with gusts near 20 mph possible.

For Thursday, minimum relative humidity will range from around 25 to 35 percent with temperatures mostly in the 70s again.
Southeast winds near 10 mph with gusts near 15-20 mph possible.

PHI WATCHES/WARNINGS/ADVISORIES
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...Small Craft Advisory until 7 PM EDT this evening for ANZ430- 431.
Small Craft Advisory until 6 AM EDT Wednesday for ANZ450>455.