Small Craft Advisory 40, NWS Baltimore/Washington

590 
WHUS71 KLWX 151145
MWWLWX

URGENT - MARINE WEATHER MESSAGE
National Weather Service Baltimore MD/Washington DC
645 AM EST Mon Feb 15 2021

ANZ533-534-537-543-151945-
/O.EXP.KLWX.SC.Y.0040.000000T0000Z-210215T1200Z/
/O.NEW.KLWX.SC.Y.0041.210216T0500Z-210216T1400Z/
Chesapeake Bay from North Beach to Drum Point MD-
Chesapeake Bay from Drum Point MD to Smith Point VA-
Tidal Potomac from Cobb Island MD to Smith Point VA-
Tangier Sound and the inland waters surrounding Bloodsworth
Island-
645 AM EST Mon Feb 15 2021

...SMALL CRAFT ADVISORY IN EFFECT FROM MIDNIGHT TONIGHT TO 9 AM
EST TUESDAY...
...SMALL CRAFT ADVISORY WILL EXPIRE AT 7 AM EST THIS MORNING...

* WHAT...South winds 10 to 20 kt with gusts up to 25 kt expected.

* WHERE...Chesapeake Bay from North Beach MD to Smith Point VA, 
  Tidal Potomac from Cobb Island MD to Smith Point VA, and 
  Tangier Sound and the inland waters surrounding Bloodsworth 
  Island.

* WHEN...From midnight tonight to 9 AM EST Tuesday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

ANZ541-542-151945-
/O.NEW.KLWX.SC.Y.0041.210216T0500Z-210216T1400Z/
Choptank River to Cambridge MD and the Little Choptank River-
Patuxent River to Broomes Island MD-
645 AM EST Mon Feb 15 2021

...SMALL CRAFT ADVISORY IN EFFECT FROM MIDNIGHT TONIGHT TO 9 AM
EST TUESDAY...

* WHAT...South winds 10 to 15 kt with gusts up to 20 kt expected.

* WHERE...Choptank River to Cambridge MD and the Little Choptank 
  River and Patuxent River to Broomes Island MD.

* WHEN...From midnight tonight to 9 AM EST Tuesday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
932 PM EST Sun Feb 14 2021

.SYNOPSIS...
Arctic high pressure is forecast to remain anchored over the
central United States into southeastern Canada through much of
the upcoming week. Multiple waves of low pressure developing
over the Deep South and moving up the East Coast will bring
multiple threats for wintry precipitation to the region.

&&

.NEAR TERM /THROUGH MONDAY/...
The latest observations reveal that temperatures at 9pm this
evening along and east of US 29 are above freezing. To the west
of US 29, temperatures are at or below freezing. We will hold
onto the Winter Weather Advisory through the remainder of the
night as lingering moisture and fluctuating temperatures near or
below freezing could lead to light freezing rain or freezing
drizzle. Radar doesn't show much, except for some light rain
moving across southern Maryland, where temperatures range from
34 to 37 degrees. Perhaps, there are a few echos across Culpeper
County in central Virginia, where temperatures are around 34
degrees. All in all, a light and/or intermittent freezing
drizzle is still possible almost anywhere the remainder of the
night.

The next low pressure system is expected to ride along the
Appalachian Mountains on Monday. Near freezing temperatures,
particularly over the ridges, may result in light freezing
rain/drizzle. Confidence remains low to carry an advisory. Model
guidance from earlier this afternoon reveals potentially plain
rain in many places.

&&

.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
A stronger low pressure system will move northeast from the
northwest Gulf of Mexico toward the Appalachians Monday. Colder
air moving into place at the surface in our northwestern zones
could lead to some significant icing, especially across higher
elevations of northern and western Maryland and Potomac
Highlands.

Further south and east, temperatures should be more marginal and
could favor more rain. Some of the colder guidance still suggest
that wintry mix precipitation could approach the metro areas.

This whole system should exit quickly Tuesday morning, resulting
in a drier but brisk day. At least filtered sunshine seems
likely by Tuesday afternoon over much of the area east of the
higher elevations, but a few snow showers are possible along and
west of the Allegheny Front.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
We should see a brief break in the inclement weather Wednesday
as high pressure settles in just to the west of the Great Lakes
before migrating eastward towards the Northeast. A fairly dry
day is forecast on Wednesday with a wind out of the N/NE, along
with lower-level moisture still in place, keeping the cloud deck
somewhat dense across the area. The break in the action is expected
to be brief in nature as a the next disturbance begins to move
into the area from Wednesday night/Thursday morning.

With the anticipated position of high pressure to our north,
we should see a good amount of cold air sinking down into the
area. This would allow for a chance of wintry precipitation to
build in before daytime heating settles in on Thursday. The
trend in the latest guidance (led by the ECMWF) has been colder,
with a low pressure track over or just south of the region due
to a strong blocking high pressure over New England (this high
pressure may be stronger as a result of stronger middle-level
confluence in the wake of early week system, which has also been
trending stronger). With the moisture source from the Gulf of
Mexico and overall longevity of this system, ensemble guidance
continues show the possibility for over an inch liquid equivalent
precipitation across the area during this time period.

This system is expected to depart by Friday afternoon with
model guidance being in pretty good agreement with timing of
this event. In its wake, we will likely see a gusty NW wind
behind the associated frontal passage, leading to the potential
for some upslope snow showers for the Allegheny Front Friday
night/Saturday. High pressure is forecast to build back in from
the Deep South Saturday, allowing for drying/warming trend.
Temperatures may bounce back to near normal for this time of year.

&&

.AVIATION /02Z MONDAY THROUGH FRIDAY/...
Lowering ceilings and patchy drizzle or light rain could evolve
through the night at many of the terminals. Temperatures will
be near or below freezing for KMRB/KCHO, which may result in
light icing. For KIAD/KDCA/KBWI/KMTN, temperatures are expected
to be just above freezing at the surface, but a sub- freezing
layer is likely just above the surface.

The ceiling and visibility will likely remain low Monday
through Tuesday in a continued overrunning pattern. A wintry mix
is possible mainly near KMRB, with mainly rain most likely for
the rest of the terminals Monday night. Lower-level wind shear
is possible toward daybreak Tuesday.

Sub-VFR conditions are possible Wednesday night into Thursday
as an impending low pressure moves into the area. Wintry
precipitation is possible, and the latest guidance (led by the
ECMWF) has trended notably colder.

&&

.MARINE...
A northerly wind should remain at or below 10 knots through
Monday as the pressure gradient remains weak. The gradient is
forecast to tighten a bit Monday night into Tuesday as the
surface wind turns easterly then southerly, which may result in
gusts of 20 to 25 knots.

With high pressure progged to be overhead Wednesday, we are not
expecting any marine hazards to be present briefly during the
day. As an impending low pressure system makes passage Wednesday
night into Thursday, Small Craft Advisories may be needed with
tighter pressure gradients overlaying the marine district by
Thursday morning. Expect a gusty NW wind as this system passes
Friday afternoon.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Winter Weather Advisory until 10 AM EST Monday for MDZ001-
     003>005-501-502.
     Winter Weather Advisory until 10 AM EST Monday for MDZ006-503-
     505-507.
     Winter Storm Watch from Monday evening through Tuesday morning
     for MDZ001-003-501-502.
VA...Winter Weather Advisory until 10 AM EST Monday for VAZ025>031-
     503-504-507-508.
     Winter Weather Advisory until 10 AM EST Monday for VAZ036>040-
     501-505.
WV...Winter Weather Advisory until 10 AM EST Monday for WVZ050>053-
     055-501>506.
     Winter Storm Watch from Monday evening through Tuesday morning
     for WVZ050-051-503-504.
MARINE...None.

&&

SYNOPSIS...DHOF
NEAR TERM...KLW/DHOF
SHORT TERM...DHOF
LONG TERM...ADM
AVIATION...KLW/ADM
MARINE...KLW/ADM

Hazardous Weather Outlook
National Weather Service Baltimore MD/Washington DC
523 PM EST Sun Feb 14 2021

ANZ530>543-DCZ001-MDZ008-011-013-014-016>018-504-506-508-
VAZ052>057-151000-
Chesapeake Bay north of Pooles Island MD-
Chesapeake Bay from Pooles Island to Sandy Point MD-
Chesapeake Bay from Sandy Point to North Beach MD-
Chesapeake Bay from North Beach to Drum Point MD-
Chesapeake Bay from Drum Point MD to Smith Point VA-
Tidal Potomac from Key Bridge to Indian Head MD-
Tidal Potomac from Indian Head to Cobb Island MD-
Tidal Potomac from Cobb Island MD to Smith Point VA-
Patapsco River including Baltimore Harbor-
Chester River to Queenstown MD-Eastern Bay-
Choptank River to Cambridge MD and the Little Choptank River-
Patuxent River to Broomes Island MD-
Tangier Sound and the inland waters surrounding Bloodsworth
Island-District of Columbia-Cecil-Southern Baltimore-
Prince Georges-Anne Arundel-Charles-St. Marys-Calvert-
Central and Southeast Montgomery-Central and Southeast Howard-
Southeast Harford-Prince William/Manassas/Manassas Park-Fairfax-
Arlington/Falls Church/Alexandria-Stafford-Spotsylvania-
King George-
523 PM EST Sun Feb 14 2021

This Hazardous Weather Outlook is for the Maryland portion of the
Chesapeake Bay, Tidal Potomac River, and I-95 corridor through
central Maryland, northern Virginia, and District of Columbia.

.DAY ONE...Tonight

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Monday through Saturday

There is an enhanced winter storm threat late Wednesday night
into Thursday. There is increased potential of more significant
travel impacts and closures.

.SPOTTER INFORMATION STATEMENT...

Spotters are asked to report winter weather via standard
operating procedures.

MDZ003>006-503-505-507-VAZ025>031-036>040-050-051-501-502-505>508-
WVZ050>053-055-151000-
Washington-Frederick MD-Carroll-Northern Baltimore-
Northwest Montgomery-Northwest Howard-Northwest Harford-Augusta-
Rockingham-Shenandoah-Frederick VA-Page-Warren-Clarke-Nelson-
Albemarle-Greene-Madison-Rappahannock-Orange-Culpeper-
Northern Fauquier-Southern Fauquier-Western Loudoun-
Eastern Loudoun-Northern Virginia Blue Ridge-
Central Virginia Blue Ridge-Hampshire-Morgan-Berkeley-Jefferson-
Hardy-
523 PM EST Sun Feb 14 2021

This Hazardous Weather Outlook is for portions of eastern West
Virginia, northern and central Virginia, and central and western
Maryland.

.DAY ONE...Tonight

A Winter Weather Advisory is in effect for much of the area
tonight.

.DAYS TWO THROUGH SEVEN...Monday through Saturday

The Winter Weather Advisory is in effect until 10 AM Monday.

A Winter Storm Watch is in effect for Hardy, Morgan, and
Washington Counties Monday night. Significant icing is possible in
these areas. Lesser amounts of ice or a wintry mix are possible
for the rest of the outlook area Monday night, primarily for the
higher elevations. This would cause travel disruptions.

There is an enhanced winter storm threat late Wednesday night
into Friday morning. There is increased potential of more significant
travel impacts and closures.

.SPOTTER INFORMATION STATEMENT...

Spotters are asked to report winter weather via standard
operating procedures.

MDZ001-501-502-VAZ503-504-WVZ501>506-151000-
Garrett-Extreme Western Allegany-Central and Eastern Allegany-
Western Highland-Eastern Highland-Western Grant-Eastern Grant-
Western Mineral-Eastern Mineral-Western Pendleton-
Eastern Pendleton-
523 PM EST Sun Feb 14 2021

This Hazardous Weather Outlook is for the Allegheny Front
counties in western Maryland, eastern West Virginia, and Highland
County Virginia.

.DAY ONE...Tonight

A Winter Weather Advisory is in effect for tonight.

.DAYS TWO THROUGH SEVEN...Monday through Saturday

The Winter Weather Advisory is in effect until 10 AM Monday.

A Winter Storm Watch is in effect for Allegany, Garrett, and
Mineral Counties Monday night. Significant icing is possible in
these areas. Lesser amounts of ice or a wintry mix are possible
for the rest of the outlook area Monday night, which would cause
travel disruptions.

There is a moderate winter storm threat late Wednesday night into
Friday morning. Potential impacts include significant significant
travel delays and closures. Plan ahead to minimize impact on you
and your family.

.SPOTTER INFORMATION STATEMENT...

Spotters are asked to report winter weather via standard
operating procedures.