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fxus61 klwx 261854 

Area forecast discussion
National Weather Service Baltimore Maryland/Washington District of Columbia
254 PM EDT Mon Jun 26 2017

Synopsis...a sharp upper level trough will move across the
region on Tuesday. High pressure builds over the area Wednesday
and moves offshore Thursday.


Near term /through tonight/...quiet conditions tonight under
weak high pressure. Some high clouds will start moving in late
tonight and early Tue. Cool with lows in the 50s except mid 60s
in city centers.


Short term /Tuesday through Wednesday night/...a sharp upper
level trough will move across the area late tomorrow. Strong
height falls will provide large scale forcing for showers and
thunderstorms to develop. Biggest limiting factor is lack of
low-level moisture and weak instability with cape values progged
at less than 250 j/kg. Best coverage of showers will be east of
the Blue Ridge mtns where instability will be higher. Showers
will only produce very light rainfall due to relatively high
base clouds and a ton of mid-level dry air. Gusty winds and
small hail may be possible due to inverted-v soundings and very
cool temps aloft for this time of the year. -20c 500 mb temps
are progged which is near record low for late Jun.

Trough axis moves east Tue evening with rapid clearing. High
pressure builds for Wed with tranquil weather.


Long term /Thursday through Monday/...

High pressure will be in control Thursday through Thursday night,
bringing dry conditions and above normal temperatures. There
could be a stray shower along the Mason-Dixon region Thursday

As high pressure moves over the western Atlantic, warmer
temperatures and increasing chances of showers and thunderstorms
will develop Friday through Sunday. The best chance for showers and
storms will be Saturday and Sunday.

A second area of high pressure will build into the region Monday,
bringing more seasonable temperatures and dry conditions.


Aviation /19z Monday through Saturday/...VFR conditions next 72
hrs. Widely scattered or scattered showers and T-storms are
expected tomorrow. No restrictions are anticipated. High
pressure builds for Wed.

VFR conditions Thursday and Thursday night. Winds southwest 10 knots
Thursday and Thursday night. MVFR to IFR conditions are possible
with showers and storms Friday and Friday night. Winds southwest 5
to 10 knots Friday and Friday night.


Marine...srly winds expected to strengthen tonight with Small Craft Advisory
conditions. Winds will diminish toward morning. Very marginal
Small Craft Advisory conditions possible tomorrow, but not enough confidence to
issue sca, however, gusty winds in showers or T-storms may
require mwss or even smws due to very dry environment and
potential for deep mixing.

Small craft advisories may be needed Thursday and Thursday night.
Winds southwest 10 to 15 knots gusts 20 knots. No marine hazards
expected Friday and Friday night. Winds southwest around 10


Lwx watches/warnings/advisories...
District of Columbia...none.
Marine...Small Craft Advisory from 9 PM this evening to 2 am EDT
Tuesday for anz531>533-538>541.
Small Craft Advisory from 9 PM this evening to 4 am EDT
Tuesday for anz534-537-543.



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