Scientific Forecaster Discussion
fxus61 klwx 251412 aaa
Area forecast discussion...updated
National Weather Service Baltimore Maryland/Washington District of Columbia
1012 am EDT Mon Sep 25 2017
high pressure will remain in place today, then slowly weaken
its grip over the area Tuesday and Wednesday as Hurricane Maria
moves northward through the western Atlantic. A cold front will
move through Thursday, bringing more seasonable temperatures for
the end of the week. Little if any rain is expected.
Near term /through tonight/...
Ridge of high pressure will continue to hold over the region
today, but it will begin to weaken. No precip is expected as a
result. Highs again today around 90f similar to yesterday.
Tonight, the influence of Maria will increase somewhat as it
continues moving north and approaches the Outer Banks. Northeast
flow will increase, but remain in the 10-15 mph range overall.
This may allow moisture to move in from the Atlantic, so there
maybe some more patchy fog or low clouds. Otherwise, another
mild night, with lows mostly in the 60s.
Short term /Tuesday through Wednesday night/...
Maria will push northward and then stall just east of the Outer
Banks Tuesday and Wednesday before getting kicked out to sea by
an approaching trough/cold front during the long term period. It
will stay far enough away such that influence on our region will
be minimal, with just an increased northeast breeze, perhaps
reaching 25 mph in gusts in far S MD, and slightly cooler temps
thanks to increased clouds and a chance of a few showers with
highest chance near the Bay. Highs will cool slightly, but
remain well above normal with 80s continued. Lows at night still
in the 60s.
Long term /Thursday through Sunday/...
there's really not much Prospect for appreciable precip through
the weekend. The region will remain ensconced by high pressure,
with a dry cold front Thursday and an upper-level trough
Saturday the only exceptions. The guidance has trended quicker
and flatter with the Saturday trough, which lowers the chance
for widespread precipitation, though an increase in clouds and a
few scattered showers are still plausible.
Gusty winds are likely both Thursday behind the dry frontal
passage and again Saturday with the trough axis. Although it
will be noticeably breezy, wind gusts in both periods should
remain well below any headline criteria over land.
Aviation /14z Monday through Friday/...
VFR generally expected through Wednesday. Patchy fog possible
which could result in reduced vis at mrb, cho and perhaps even
iad, though odds at the latter are lower. Fog possible again
tomorrow night, though odds reduced as surface winds will begin
to increase as Maria gets a little closer. Maria unlikely to
produce much effect on local weather other than a northeast to
north breeze perhaps gusting to 20 knots Tuesday and Wednesday,
and perhaps a stray shower.
Mainly VFR expected to end the week. Gusty north winds Thu behind
frontal passage, becoming lighter Fri.
winds sub Small Craft Advisory today as high pressure lingers. Winds will start
to increase tonight into Tuesday as Maria approaches NC from the
southeast. Wind field will be expanding, so issued Small Craft Advisory for our
southernmost Bay zones, but looks marginal to be sure. Small Craft Advisory
likely to continue through Wednesday, mainly our southernmost
Bay zones though. Otherwise, no more than a stray shower
expected from Maria.
Solid Small Craft Advisory conditions likely in northerly surge behind a cold
frontal passage Thursday. Gales possible.
anomalies have receded significantly for the time being, but
will gradually increase as Maria brushes NC and heads out to
sea. The threat for (minor) flooding will likely return by
Tuesday afternoon and linger into early Thursday.
District of Columbia...none.
Marine...Small Craft Advisory from 10 am to 6 PM EDT Tuesday for anz534-