Wind Advisory 4, NWS Baltimore/Washington

356 
WWUS71 KLWX 080803
NPWLWX

URGENT - WEATHER MESSAGE
National Weather Service Baltimore MD/Washington DC
303 AM EST Wed Feb 8 2017

VAZ507-508-080915-
/O.CAN.KLWX.WI.Y.0004.000000T0000Z-170208T1100Z/
Northern Virginia Blue Ridge-Central Virginia Blue Ridge-
Including the cities of Big Meadows and Wintergreen
303 AM EST Wed Feb 8 2017

...WIND ADVISORY IS CANCELLED...

The National Weather Service in Baltimore MD/Washington has
cancelled the Wind Advisory.

Winds will continue to decrease through the morning hours.

$$

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
250 PM EST Tue Feb 7 2017

.SYNOPSIS...A warm front is situated across Pennsylvania. A
cold front will drop into the area Wednesday, then stall to the
south as low pressure rides along it Wednesday night into
Thursday. High pressure and cooler temperatures will return late
in the week.

&&

.NEAR TERM /THROUGH WEDNESDAY/...Very warm conditions will
prevail tonight as area remains in the warm sector ahead of low
pressure and cdfnt moving through the eastern Great Lks. Another
round of showers is expected tonight as cdfnt approaches. Cdfnt
crosses the area around 12Z with showers ending. Not as warm
with temps in the low 60s.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...Secondary
low pressure forms across southwest VA Wed evening and tracks
ENE across southern MD and off the Delmarva Thu morning. Guidance
this cycle have trended further north with track of sfc and 850
mb lows, but is also more amplified and more developed with the
sfc low. Rain is expected Wed evening across all areas, although
it could start late Wed over the Potomac highlands. Colder air
will start filtering into far northwest counties around midnight
Wed night with the latest ECMWF bringing the cold air much
faster than the GFS. Rain will gradually change to snow across
the northern MD counties late Wed night, but initially sfc temps
are likely to remain above freezing causing the snow to melt on
contact. The 12Z GFS/GFES mean show most of the accumulating
snow over southeast PA with 1-2 inches from Frederick county
east to Harford, while the 12Z ECMWF is more bullish given its
farther south solution with the track of the sfc/850 mb low.
Consensus is that we'll see advisory criteria snows across nrn
MD counties.

Precip associated with the sfc low moves out of the area around
12Z Thu. Colder air will filter in as winds strengthen behind
departing and intensifying sfc low. Atmosphere will then become
supportive of snow squalls as upper trough axis moves through
and lapse rates steepen. Squalls may cause localized snow
accumulations of half inch or more which would stick to roads
easily given falling temperatures and also cause sudden changes
in visibility. These squalls could have significant impacts to
the Thu afternoon rush hour commute. In addition, wind chill
values will also be dropping to critical thresholds in the
Potomac highlands which may require wind chill advisories.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...High pressure will keep dry
conditions into Friday night as it moves offshore. SSW flow
builds in on Friday night into Saturday bringing high
temperatures into the 50s. Cold front approaches from the west
Saturday night and it stalls over or near us on Sunday,
increasing PoPs over the area. A cold front moves across on
Monday and a high pressure builds behind it.

High temperatures will be in the 30s and 40s for Friday, increasing
to the 50s and 60s Saturday and Sunday, and for some areas on
Monday. High temperatures decrease slightly for Tuesday.

&&

.AVIATION /19Z TUESDAY THROUGH SUNDAY/...Cdfnt will cross the
area Wed morning with a wind shift. Low pres will move south of
the area Wed night with rain expected. Rain will gradually to
snow Thu morning. Numerous snow showers expected Thu afternoon
which may result in sudden changes in visibility and slippery
conditions.

VFR conditions expected on Friday and Saturday, sub-VFR
conditions possible Saturday night into Monday.

&&

.MARINE...SCA conditions through Thu morning. Gale conditions
likely for portions of the waters Thu afternoon and night under
strong NW flow.

Breezy conditions over the waters possible Friday into Friday
night... therefore a small craft advisory may be needed. Winds
fall below the threshold for Saturday into Sunday.

&&

.CLIMATE...

Here are the calendar record highs and warm lows for the three major
airports.

Feb 7   Record High     Record Warm Low
DCA     64 (2008, 1887) 47 (1904)
BWI     64 (1904)       45 (1991)*
IAD     65 (2009)       46 (1991)

* BWI has already dropped below 45 so that won't be broken.

Feb 8   Record high     Record Warm Low
DCA     68 (2015, 1900) 42 (1882)
BWI     70 (1965)       44 (1965)
IAD     70 (1965)       41 (2009)

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...Small Craft Advisory until 6 AM EST Wednesday for ANZ531>534-
     537-539>541-543.
     Small Craft Advisory until 3 AM EST Wednesday for ANZ530-535-
     536-538-542.

&&

SYNOPSIS...LFR
NEAR TERM...LFR
SHORT TERM...LFR
LONG TERM...IMR
AVIATION...IMR/LFR
MARINE...IMR/LFR
CLIMATE...DFH

Hazardous Weather Outlook
National Weather Service Baltimore MD/Washington DC
435 PM EST Tue Feb 7 2017

ANZ530>543-DCZ001-MDZ011-013-014-016>018-508-VAZ052>057-081000-
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-Southern Baltimore-Prince Georges-
Anne Arundel-Charles-St. Marys-Calvert-Southeast Harford-
Prince William/Manassas/Manassas Park-Fairfax-
Arlington/Falls Church/Alexandria-Stafford-Spotsylvania-
King George-
435 PM EST Tue Feb 7 2017

This Hazardous Weather Outlook is for the Maryland portion of the
Chesapeake Bay, Tidal Potomac River, and adjacent counties in
central Maryland and northern Virginia as well as the District of
Columbia.

.DAY ONE...Tonight

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Accumulating snow is possible Wednesday night, particularly in
Baltimore and Harford counties.

Numerous snow showers are likely Thursday afternoon which could
result in localized accumulations and sudden changes in
visibility. The Thursday afternoon rush hour commute could be
impacted.

Gale force winds are possible for portions of the waters Thursday
afternoon and night.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

MDZ003>006-501>507-VAZ025>031-036>040-050-051-501>508-WVZ050>053-
055-501>506-081000-
Washington-Frederick MD-Carroll-Northern Baltimore-
Extreme Western Allegany-Central and Eastern Allegany-
Northwest Montgomery-Central and Southeast Montgomery-
Northwest Howard-Central and Southeast Howard-Northwest Harford-
Augusta-Rockingham-Shenandoah-Frederick VA-Page-Warren-Clarke-
Nelson-Albemarle-Greene-Madison-Rappahannock-Orange-Culpeper-
Northern Fauquier-Southern Fauquier-Western Highland-
Eastern Highland-Western Loudoun-Eastern Loudoun-
Northern Virginia Blue Ridge-Central Virginia Blue Ridge-
Hampshire-Morgan-Berkeley-Jefferson-Hardy-Western Grant-
Eastern Grant-Western Mineral-Eastern Mineral-Western Pendleton-
Eastern Pendleton-
435 PM EST Tue Feb 7 2017

This Hazardous Weather Outlook is for eastern West Virginia,
northern and central Virginia, and central and western Maryland
with the exception of Garrett County.

.DAY ONE...Tonight

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Accumulating snow is likely Wednesday night...particularly for
northern Maryland...the Allegheny and Potomac Highlands...eastern
West Virginia and extreme northern Virginia.

Wind chill values of ten below zero are possible across the
Potomac highlands Thursday night and Friday morning.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.