Marine Weather and Tide Forecast for Indian Head, MD

KEY MESSAGES
-1) A warming trend ensues through the remainder of the work week, with rain chances by late Friday.

-2) Temperatures warm through the weekend with a cold front bringing cooler temperatures early next week.

DISCUSSION
KEY MESSAGE 1...A warming trend ensues through the remainder of the work week, with rain chances by late Friday.

A highly amplified synoptic pattern continues across the continental U.S. While an anomalous ridge persists over the southwestern U.S., broad troughing extends across the Mississippi Valley to the Eastern Seaboard. The local area remains under the influence of northwesterly flow aloft which comes with multiple embedded impulses. One such wave is currently pivoting over the region which is accompanied by a thick mid-level cloud deck. Despite surface high pressure extending along the Atlantic coast, the thickening clouds have kept most locations in the mid 30s. This is coupled by a light south to southeasterly winds. Consequently, expect temperatures to hold fairly steady through daybreak.

As the mean upper trough slowly moves eastward, a gradual building of heights will mark the start of a warming trend. More notably, the 850-mb temperatures are expected to rise by around 7-10C since yesterday/Wednesday. This is driven by a shift from northwesterly flow over to westerlies. With 850-mb forecast temperatures around -2C, dry adiabatic mixing will help raise today's highs well into the 50s. However, this comes with additional cloud cover as another perturbation in the northwesterly flow aloft tracks through. Despite the mostly cloudy conditions, this comes with a dry forecast. Seasonably cool weather is likely tonight given the persistent surface ridge with lows in the 30s.

By Friday, further warming is anticipated ahead of a quick moving clipper system. Daytime temperatures push well into the 60s, but with increasing clouds through the day. As gradients tighten ahead of this system, 850-700 mb westerly winds pick up in strength, generally averaging around 30 to 40 knots. Some of this could mix down across the Alleghenies, particularly on Friday afternoon. While the latest forecast calls for gusts to around 20 to 25 mph, these could easily be closer to 35 mph.
Elsewhere, southwesterlies will gust to around 15 to 20 mph before showers arrive later in the day. Moisture is likely to be limited which should hold total amounts to around 0.10 to 0.25 inches. Rain showers continue Friday evening and into the night before drying out by sunrise on Saturday.

Despite the cold frontal passage with this clipper system, a mainly west to northwesterly wind will yield a dry and very well mixed boundary layer on Saturday. With potential mixing into the 850-750 mb layer, forecast highs push well into the 60s to low 70s. Spotty mid 70s are possible closer to I-64.

KEY MESSAGE 2...Temperatures warm through the weekend with a cold front bringing cooler temperatures early next week.

Surface high pressure retreats offshore as a strong cold front approaches from the northwest. Ahead of the front, temperatures will be well above normal with highs in the mid 60s to upper 70s Sunday afternoon. Precipitation chances increase Sunday afternoon as a cold front drops through the forecast area. Precipitation lingers through Monday afternoon as the cold front departs the area.

In the wake of the front, Canadian surface high pressure builds overhead with cooler temperatures expected on Monday. Highs will be in the 40s to mid 60s across the area. High pressure continues to build overhead on Tuesday with dry conditions expected areawide and highs in the 40s to mid 50s. A surface trough along the Alleghenies will bring increased precipitation chances on Tuesday.

AVIATION /06Z THURSDAY THROUGH MONDAY/
VFR conditions are expected through Friday afternoon given the influence of surface high pressure. While skies remain overcast, ceilings are largely staying in the 5,000 to 7,000 foot range. A clipper system arrives Friday evening into the night which will bring increasing shower chances. This may yield some restrictions at times through Saturday morning. For winds, gradients remain weak which will maintain light southerlies today. Southwesterlies increase on Friday with gusts to 15 to 20 knots before shifting to northwesterlies behind the frontal system on Saturday. Winds turn lighter into the night.

West winds in the morning shift to northwest in the wake of a cold front Sunday afternoon. Winds increase to around 10 knots, gusting to 20 knots. Precipitation chances increase across the terminals Sunday afternoon and into the overnight as a cold front approaches from the northwest. VFR conditions are expected during the day with restrictions possible overnight during precipitation.
Precipitation chances and sub-VFR conditions linger Monday in the wake of a cold front. Northwest winds gust to 20 knots.

MARINE
High pressure continues its presence along the Atlantic coast.
Despite the weak gradients, south to southeasterlies have increased to around 12 to 17 knots over the middle Chesapeake Bay. If this trend continues, Marine Weather Statements may be issued to cover this marginal threat.

Through midday Friday, southerly winds should stay below advisory levels. However, expect a further uptick ahead of a quick moving clipper system as winds turn more south to southwesterly. Small Craft Advisories may be needed from Friday evening into the night as gusts push to around 20 knots. Post- frontal northwesterlies actually decrease a bit on Saturday before light southerlies return by late Saturday.

West winds on Sunday morning shift to northwest in the wake of a cold front Sunday afternoon. Small Craft Advisories are likely throughout the day as winds gust 20 knots. Winds remain out of the northwest on Monday with Small Craft Advisories likely, mainly over the Chesapeake Bay and southern Potomac. Winds diminish below SCA criteria Monday night.



LWX WATCHES/WARNINGS/ADVISORIES
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...None.